<?xml version="1.0" encoding="us-ascii" standalone="yes"?>
<!--XBRL Document Created with XBRLMaster-->
<!--Version: 2.3.08-->
<!--Based on XBRL 2.1-->
<!--Date of creation: 09/10/2026-->
<!--Software architectural design and coding: A'c Dharmapremananda Avt.-->
<!--Copyright (c) 2026 I-NET Business Solutions, Inc. All Rights Reserved.-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://cney.com/role/Cover" xlink:href="cney-20250930.xsd#Cover" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConsolidatedBalanceSheets" xlink:href="cney-20250930.xsd#ConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:href="cney-20250930.xsd#ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConsolidatedStatementsOfIncomeLossAndComprehensiveIncomeLoss" xlink:href="cney-20250930.xsd#ConsolidatedStatementsOfIncomeLossAndComprehensiveIncomeLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConsolidatedStatementsOfChangesInShareholdersEquity" xlink:href="cney-20250930.xsd#ConsolidatedStatementsOfChangesInShareholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConsolidatedStatementsOfCashFlows" xlink:href="cney-20250930.xsd#ConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OrganizationAndNatureOfBusiness" xlink:href="cney-20250930.xsd#OrganizationAndNatureOfBusiness" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SummaryOfSignificantAccountingPolicies" xlink:href="cney-20250930.xsd#SummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccountsReceivableNet" xlink:href="cney-20250930.xsd#AccountsReceivableNet" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/Inventories" xlink:href="cney-20250930.xsd#Inventories" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AdvancesToSuppliersNet" xlink:href="cney-20250930.xsd#AdvancesToSuppliersNet" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OtherReceivable" xlink:href="cney-20250930.xsd#OtherReceivable" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LoanToAThirdParty" xlink:href="cney-20250930.xsd#LoanToAThirdParty" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AcquisitionReversalReceivable" xlink:href="cney-20250930.xsd#AcquisitionReversalReceivable" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestments" xlink:href="cney-20250930.xsd#LongTermInvestments" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/BiologicalAssets" xlink:href="cney-20250930.xsd#BiologicalAssets" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/PropertyPlantAndEquipmentNet" xlink:href="cney-20250930.xsd#PropertyPlantAndEquipmentNet" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LandUseRightNet" xlink:href="cney-20250930.xsd#LandUseRightNet" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConvertibleNote" xlink:href="cney-20250930.xsd#ConvertibleNote" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilities" xlink:href="cney-20250930.xsd#AccruedExpensesAndOtherCurrentLiabilities" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/RelatedPartyTransactions" xlink:href="cney-20250930.xsd#RelatedPartyTransactions" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ShareholdersEquity" xlink:href="cney-20250930.xsd#ShareholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/Taxes" xlink:href="cney-20250930.xsd#Taxes" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConcentrationOfMajorCustomersAndSuppliers" xlink:href="cney-20250930.xsd#ConcentrationOfMajorCustomersAndSuppliers" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/Leases" xlink:href="cney-20250930.xsd#Leases" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SegmentReporting" xlink:href="cney-20250930.xsd#SegmentReporting" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CommitmentsAndContingencies" xlink:href="cney-20250930.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/DispositionOfSubsidiaries" xlink:href="cney-20250930.xsd#DispositionOfSubsidiaries" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SubsequentEvents" xlink:href="cney-20250930.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CondensedFinancialInformationOfTheParentCompany" xlink:href="cney-20250930.xsd#CondensedFinancialInformationOfTheParentCompany" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SignificantAccountingPoliciesPolicies" xlink:href="cney-20250930.xsd#SignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OrganizationAndNatureOfBusinessTables" xlink:href="cney-20250930.xsd#OrganizationAndNatureOfBusinessTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:href="cney-20250930.xsd#SummaryOfSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccountsReceivableNetTables" xlink:href="cney-20250930.xsd#AccountsReceivableNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/InventoriesTables" xlink:href="cney-20250930.xsd#InventoriesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AdvancesToSuppliersNetTables" xlink:href="cney-20250930.xsd#AdvancesToSuppliersNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OtherReceivableTables" xlink:href="cney-20250930.xsd#OtherReceivableTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LoanToAThirdPartyTables" xlink:href="cney-20250930.xsd#LoanToAThirdPartyTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestmentsTables" xlink:href="cney-20250930.xsd#LongTermInvestmentsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/BiologicalAssetsTables" xlink:href="cney-20250930.xsd#BiologicalAssetsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/PropertyPlantAndEquipmentNetTables" xlink:href="cney-20250930.xsd#PropertyPlantAndEquipmentNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LandUseRightNetTables" xlink:href="cney-20250930.xsd#LandUseRightNetTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:href="cney-20250930.xsd#AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/RelatedPartyTransactionsTables" xlink:href="cney-20250930.xsd#RelatedPartyTransactionsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/TaxesTables" xlink:href="cney-20250930.xsd#TaxesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LeasesTables" xlink:href="cney-20250930.xsd#LeasesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SegmentReportingTables" xlink:href="cney-20250930.xsd#SegmentReportingTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/DispositionOfSubsidiariesTables" xlink:href="cney-20250930.xsd#DispositionOfSubsidiariesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyTables" xlink:href="cney-20250930.xsd#CondensedFinancialInformationOfTheParentCompanyTables" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OrganizationAndNatureOfBusinessDetails" xlink:href="cney-20250930.xsd#OrganizationAndNatureOfBusinessDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OrganizationAndNatureOfBusinessDetailsNarrative" xlink:href="cney-20250930.xsd#OrganizationAndNatureOfBusinessDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetails" xlink:href="cney-20250930.xsd#SummaryOfSignificantAccountingPoliciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetails1" xlink:href="cney-20250930.xsd#SummaryOfSignificantAccountingPoliciesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:href="cney-20250930.xsd#SummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccountsReceivableNetDetails" xlink:href="cney-20250930.xsd#AccountsReceivableNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccountsReceivableNetDetails1" xlink:href="cney-20250930.xsd#AccountsReceivableNetDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/InventoriesNetDetails" xlink:href="cney-20250930.xsd#InventoriesNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/InventoriesNetDetails1" xlink:href="cney-20250930.xsd#InventoriesNetDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AdvancesToSuppliersNetDetails" xlink:href="cney-20250930.xsd#AdvancesToSuppliersNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AdvancesToSuppliersNetDetails1" xlink:href="cney-20250930.xsd#AdvancesToSuppliersNetDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OtherReceivableDetails" xlink:href="cney-20250930.xsd#OtherReceivableDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OtherReceivableDetails1" xlink:href="cney-20250930.xsd#OtherReceivableDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/OtherReceivableDetailsNarrative" xlink:href="cney-20250930.xsd#OtherReceivableDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LoanToAThirdPartyDetails" xlink:href="cney-20250930.xsd#LoanToAThirdPartyDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LoanToAThirdPartyDetailsNarrative" xlink:href="cney-20250930.xsd#LoanToAThirdPartyDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AcquisitionReversalReceivableDetailsNarrative" xlink:href="cney-20250930.xsd#AcquisitionReversalReceivableDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestmentsDetails" xlink:href="cney-20250930.xsd#LongTermInvestmentsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestmentsDetails1" xlink:href="cney-20250930.xsd#LongTermInvestmentsDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestmentsDetails2" xlink:href="cney-20250930.xsd#LongTermInvestmentsDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LongTermInvestmentsDetailsNarrative" xlink:href="cney-20250930.xsd#LongTermInvestmentsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/BiologicalAssetsDetails" xlink:href="cney-20250930.xsd#BiologicalAssetsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/BiologicalAssetsDetailsNarrative" xlink:href="cney-20250930.xsd#BiologicalAssetsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/PropertyAndEquipmentNetDetails" xlink:href="cney-20250930.xsd#PropertyAndEquipmentNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/PropertyAndEquipmentNetDetailsNarrative" xlink:href="cney-20250930.xsd#PropertyAndEquipmentNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LandUseRightNetDetails" xlink:href="cney-20250930.xsd#LandUseRightNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LandUseRightNetDetailsNarrative" xlink:href="cney-20250930.xsd#LandUseRightNetDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConvertibleNoteDetailsNarrative" xlink:href="cney-20250930.xsd#ConvertibleNoteDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:href="cney-20250930.xsd#AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/RelatedPartyTransactionsDetailsNarrative" xlink:href="cney-20250930.xsd#RelatedPartyTransactionsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ShareholdersEquityDetailsNarrative" xlink:href="cney-20250930.xsd#ShareholdersEquityDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/TaxesDetails" xlink:href="cney-20250930.xsd#TaxesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/TaxesDetails1" xlink:href="cney-20250930.xsd#TaxesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/TaxesDetails2" xlink:href="cney-20250930.xsd#TaxesDetails2" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/TaxesDetailsNarrative" xlink:href="cney-20250930.xsd#TaxesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/ConcentrationOfMajorCustomersAndSuppliersDetailsNarrative" xlink:href="cney-20250930.xsd#ConcentrationOfMajorCustomersAndSuppliersDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LeasesDetails" xlink:href="cney-20250930.xsd#LeasesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/LeasesDetailsNarrative" xlink:href="cney-20250930.xsd#LeasesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SegmentReportingDetails" xlink:href="cney-20250930.xsd#SegmentReportingDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:href="cney-20250930.xsd#CommitmentsAndContingenciesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/DisposalOfSubsidiariesDetails" xlink:href="cney-20250930.xsd#DisposalOfSubsidiariesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/DisposalOfSubsidiariesDetails1" xlink:href="cney-20250930.xsd#DisposalOfSubsidiariesDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/DisposalOfSubsidiariesDetailsNarrative" xlink:href="cney-20250930.xsd#DisposalOfSubsidiariesDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/SubsequentEventsDetailsNarrative" xlink:href="cney-20250930.xsd#SubsequentEventsDetailsNarrative" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails" xlink:href="cney-20250930.xsd#CondensedFinancialInformationOfTheParentCompanyDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails1" xlink:href="cney-20250930.xsd#CondensedFinancialInformationOfTheParentCompanyDetails1" xlink:type="simple" />
  <link:roleRef roleURI="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails2" xlink:href="cney-20250930.xsd#CondensedFinancialInformationOfTheParentCompanyDetails2" xlink:type="simple" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll" arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" />
  <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/Cover" xlink:title="00000001 - Document - Cover Page Information">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CoverAbstract" xlink:label="loc_deiCover" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationTable" xlink:label="loc_deiDocumentInformationTable" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationLineItems" xlink:label="loc_deiDocumentInformationLineItems" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_deiDocumentInformationLineItems" xlink:to="loc_deiDocumentInformationTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_ContactPersonnelName" xlink:label="loc_deiContactPersonnelName" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiDocumentInformationLineItems" xlink:to="loc_deiContactPersonnelName" order="101" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode" xlink:label="loc_deiCityAreaCode" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiDocumentInformationLineItems" xlink:to="loc_deiCityAreaCode" order="102" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber" xlink:label="loc_deiLocalPhoneNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiDocumentInformationLineItems" xlink:to="loc_deiLocalPhoneNumber" order="103" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_ContactPersonnelEmailAddress" xlink:label="loc_deiContactPersonnelEmailAddress" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiDocumentInformationLineItems" xlink:to="loc_deiContactPersonnelEmailAddress" order="104" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressesAddressTypeAxis" xlink:label="loc_deiEntityAddressesAddressTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_deiDocumentInformationTable" xlink:to="loc_deiEntityAddressesAddressTypeAxis" order="30" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AddressTypeDomain" xlink:label="loc_deiAddressTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_deiEntityAddressesAddressTypeAxis" xlink:to="loc_deiAddressTypeDomain" order="40" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AddressTypeDomain" xlink:label="loc_deiAddressTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_deiEntityAddressesAddressTypeAxis" xlink:to="loc_deiAddressTypeDomain_10" order="50" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_BusinessContactMember" xlink:label="loc_deiBusinessContactMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiAddressTypeDomain" xlink:to="loc_deiBusinessContactMember" order="152" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConsolidatedBalanceSheets" xlink:title="110200 - Statement - CONSOLIDATED BALANCE SHEETS">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassABOrdinaryShareMember" xlink:label="loc_cneyClassABOrdinaryShareMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyClassABOrdinaryShareMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_OrdinaryShareClassBMember" xlink:label="loc_cneyOrdinaryShareClassBMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyOrdinaryShareClassBMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaapAssetsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsAbstract" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaapAssetsCurrentAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsCurrentAbstract" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableNetCurrent" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInventoryNet" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdvancesOnInventoryPurchases" xlink:label="loc_us-gaapAdvancesOnInventoryPurchases" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAdvancesOnInventoryPurchases" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivables" xlink:label="loc_us-gaapOtherReceivables" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherReceivables" order="7" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LoanToAThirdPartyCurrent" xlink:label="loc_cneyLoanToAThirdPartyCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLoanToAThirdPartyCurrent" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AcquisitionReversalReceivableCurrent" xlink:label="loc_cneyAcquisitionReversalReceivableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAcquisitionReversalReceivableCurrent" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsCurrent" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsNoncurrentAbstract" xlink:label="loc_us-gaapAssetsNoncurrentAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsNoncurrentAbstract" order="12" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_BiologicalAssetsNet" xlink:label="loc_cneyBiologicalAssetsNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyBiologicalAssetsNet" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments" xlink:label="loc_us-gaapLongTermInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermInvestments" order="14" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LandUseRightsNoncurrentNet" xlink:label="loc_cneyLandUseRightsNoncurrentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLandUseRightsNoncurrentNet" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet" order="16" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LeaseRightOfUseAssetsNoncurrentNet" xlink:label="loc_cneyLeaseRightOfUseAssetsNoncurrentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLeaseRightOfUseAssetsNoncurrentNet" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsNoncurrent" xlink:label="loc_us-gaapAssetsNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssetsNoncurrent" order="18" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets" order="19" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract" order="20" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaapLiabilitiesCurrentAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesCurrentAbstract" order="21" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent" order="22" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConvertibleLongTermNotePayable" xlink:label="loc_cneyConvertibleLongTermNotePayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConvertibleLongTermNotePayable" order="23" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DueToRelatedPartiesCurrentAmounts" xlink:label="loc_cneyDueToRelatedPartiesCurrentAmounts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDueToRelatedPartiesCurrentAmounts" order="24" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_RemainingAcquisitionConsiderationPayable" xlink:label="loc_cneyRemainingAcquisitionConsiderationPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyRemainingAcquisitionConsiderationPayable" order="25" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxesPayableCurrent" xlink:label="loc_us-gaapTaxesPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTaxesPayableCurrent" order="26" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" order="27" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesCurrent" order="28" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesNoncurrentAbstract" xlink:label="loc_us-gaapLiabilitiesNoncurrentAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesNoncurrentAbstract" order="29" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DueToRelatedPartiesNonCurrentAmount" xlink:label="loc_cneyDueToRelatedPartiesNonCurrentAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDueToRelatedPartiesNonCurrentAmount" order="30" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesNoncurrent" xlink:label="loc_us-gaapLiabilitiesNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesNoncurrent" order="31" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilities" order="32" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommitmentsAndContingenciesDisclosureAbstract" order="33" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaapStockholdersEquityAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquityAbstract" order="34" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockValue" order="35" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAdditionalPaidInCapital" order="36" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_StatutoryReservesValue" xlink:label="loc_cneyStatutoryReservesValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyStatutoryReservesValue" order="37" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit" order="38" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" order="39" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity" order="40" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity" order="41" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:title="110201 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_OrdinaryShareClassAMember" xlink:label="loc_cneyOrdinaryShareClassAMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyOrdinaryShareClassAMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassBOrdinaryShareMember" xlink:label="loc_cneyClassBOrdinaryShareMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyClassBOrdinaryShareMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConsolidatedStatementsOfIncomeLossAndComprehensiveIncomeLoss" xlink:title="124100 - Statement - CONSOLIDATED STATEMENTS OF INCOME (LOSS) AND COMPREHENSIVE INCOME (LOSS)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConsolidatedStatementsOfChangesInShareholdersEquity" xlink:title="148600 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaapStatementEquityComponentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementEquityComponentsAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassACommonSharesMember" xlink:label="loc_cneyClassACommonSharesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_cneyClassACommonSharesMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassBCommonSharesMember" xlink:label="loc_cneyClassBCommonSharesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_cneyClassBCommonSharesMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaapAdditionalPaidInCapitalMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAdditionalPaidInCapitalMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_StatutoryReservesMember" xlink:label="loc_cneyStatutoryReservesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_cneyStatutoryReservesMember" order="1024" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaapRetainedEarningsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapRetainedEarningsMember" order="1025" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember" order="1026" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesIssued" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForPrivatePlacementNetShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacementNetShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacementNetShares" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForPrivatePlacementNetAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacementNetAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacementNetAmount" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassBOrdinarySharesConvertedIntoClassAOrdinaryShares" xlink:label="loc_cneyClassBOrdinarySharesConvertedIntoClassAOrdinaryShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyClassBOrdinarySharesConvertedIntoClassAOrdinaryShares" order="5" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForAcquisitionAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesAndWarrantsNetShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesAndWarrantsNetShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesAndWarrantsNetShares" order="7" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesAndWarrantsNetAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesAndWarrantsNetAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesAndWarrantsNetAmount" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForServicesShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForServicesShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForServicesShares" order="9" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForServicesAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForServicesAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForServicesAmount" order="10" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForConvertibleNotesRedemptionShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemptionShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemptionShares" order="11" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForConvertibleNotesRedemptionAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemptionAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemptionAmount" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatutoryAccountingPracticesStatutoryNetIncomeAmount" xlink:label="loc_us-gaapStatutoryAccountingPracticesStatutoryNetIncomeAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatutoryAccountingPracticesStatutoryNetIncomeAmount" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax" order="15" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForWarrantsExercisedShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForWarrantsExercisedShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForWarrantsExercisedShares" order="16" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForWarrantsExercisedAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForWarrantsExercisedAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForWarrantsExercisedAmount" order="17" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchaseOfTreasurySharesShares" xlink:label="loc_cneyPurchaseOfTreasurySharesShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPurchaseOfTreasurySharesShares" order="18" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchaseOfTreasurySharesAmount" xlink:label="loc_cneyPurchaseOfTreasurySharesAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPurchaseOfTreasurySharesAmount" order="19" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DisposalOfSubsidiaries" xlink:label="loc_cneyDisposalOfSubsidiaries" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDisposalOfSubsidiaries" order="20" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_OtherComprehensiveIncomeForeignCurrencyTransactionGainLoss" xlink:label="loc_cneyOtherComprehensiveIncomeForeignCurrencyTransactionGainLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyOtherComprehensiveIncomeForeignCurrencyTransactionGainLoss" order="21" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForCommitmentFeeShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForCommitmentFeeShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForCommitmentFeeShares" order="22" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForCommitmentFeeAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForCommitmentFeeAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForCommitmentFeeAmount" order="23" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ReverseShareSplitAdjustmentsShares" xlink:label="loc_cneyReverseShareSplitAdjustmentsShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyReverseShareSplitAdjustmentsShares" order="24" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ReverseShareSplitAdjustmentsAmount" xlink:label="loc_cneyReverseShareSplitAdjustmentsAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyReverseShareSplitAdjustmentsAmount" order="25" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinaryShares" xlink:label="loc_cneyIssuanceOfOrdinaryShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinaryShares" order="26" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesAmount" order="27" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConsolidatedStatementsOfCashFlows" xlink:title="170000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OrganizationAndNatureOfBusiness" xlink:title="995551 - Disclosure - Organization and nature of business" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SummaryOfSignificantAccountingPolicies" xlink:title="995552 - Disclosure - Summary of significant accounting policies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccountsReceivableNet" xlink:title="995553 - Disclosure - Accounts receivable net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/Inventories" xlink:title="995554 - Disclosure - Inventories" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AdvancesToSuppliersNet" xlink:title="995555 - Disclosure - Advances to suppliers net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OtherReceivable" xlink:title="995556 - Disclosure - Other receivable" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LoanToAThirdParty" xlink:title="995557 - Disclosure - Loan to a third party" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AcquisitionReversalReceivable" xlink:title="995558 - Disclosure - Acquisition reversal receivable" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestments" xlink:title="995559 - Disclosure - Long-term investments" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/BiologicalAssets" xlink:title="995560 - Disclosure - Biological assets" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/PropertyPlantAndEquipmentNet" xlink:title="995561 - Disclosure - Property, plant, and equipment, net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LandUseRightNet" xlink:title="995562 - Disclosure - Land use right, net" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConvertibleNote" xlink:title="995563 - Disclosure - Convertible note" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilities" xlink:title="995564 - Disclosure - Accrued expenses and other current liabilities" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/RelatedPartyTransactions" xlink:title="995565 - Disclosure - Related party transactions" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ShareholdersEquity" xlink:title="995566 - Disclosure - Shareholders equity" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/Taxes" xlink:title="995567 - Disclosure - Taxes" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConcentrationOfMajorCustomersAndSuppliers" xlink:title="995568 - Disclosure - Concentration of major customers and suppliers" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/Leases" xlink:title="995569 - Disclosure - Leases" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SegmentReporting" xlink:title="995570 - Disclosure - Segment reporting" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CommitmentsAndContingencies" xlink:title="995571 - Disclosure - Commitments and contingencies" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/DispositionOfSubsidiaries" xlink:title="995572 - Disclosure - Disposition of subsidiaries" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SubsequentEvents" xlink:title="995573 - Disclosure - Subsequent events" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CondensedFinancialInformationOfTheParentCompany" xlink:title="995574 - Disclosure - Condensed financial information of the parent company" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SignificantAccountingPoliciesPolicies" xlink:title="995575 - Disclosure - Significant accounting policies (Policies)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OrganizationAndNatureOfBusinessTables" xlink:title="995576 - Disclosure - Organization and nature of business (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:title="995577 - Disclosure - Summary of significant accounting policies (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccountsReceivableNetTables" xlink:title="995578 - Disclosure - Accounts receivable net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/InventoriesTables" xlink:title="995579 - Disclosure - Inventories (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AdvancesToSuppliersNetTables" xlink:title="995580 - Disclosure - Advances to suppliers net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OtherReceivableTables" xlink:title="995581 - Disclosure - Other receivable (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LoanToAThirdPartyTables" xlink:title="995582 - Disclosure - Loan to a third party (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestmentsTables" xlink:title="995583 - Disclosure - Long-term investments (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/BiologicalAssetsTables" xlink:title="995584 - Disclosure - Biological assets (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/PropertyPlantAndEquipmentNetTables" xlink:title="995585 - Disclosure - Property plant and equipment net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LandUseRightNetTables" xlink:title="995586 - Disclosure - Land use right, net (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:title="995587 - Disclosure - Accrued expenses and other current liabilities (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/RelatedPartyTransactionsTables" xlink:title="995588 - Disclosure - Related party transactions (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/TaxesTables" xlink:title="995589 - Disclosure - Taxes (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LeasesTables" xlink:title="995590 - Disclosure - Leases (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SegmentReportingTables" xlink:title="995591 - Disclosure - Segment reporting (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/DispositionOfSubsidiariesTables" xlink:title="995592 - Disclosure - Disposition of subsidiaries (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyTables" xlink:title="995593 - Disclosure - Condensed financial information of the parent company (Tables)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OrganizationAndNatureOfBusinessDetails" xlink:title="995594 - Disclosure - Organization and nature of business (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaapBusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapBusinessAcquisitionAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaapBusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapBusinessAcquisitionAxis" xlink:to="loc_us-gaapBusinessAcquisitionAcquireeDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaapBusinessAcquisitionAcquireeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapBusinessAcquisitionAxis" xlink:to="loc_us-gaapBusinessAcquisitionAcquireeDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryOneMember" xlink:label="loc_cneySubsidiaryOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryOneMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryTwoMember" xlink:label="loc_cneySubsidiaryTwoMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryTwoMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryThreeMember" xlink:label="loc_cneySubsidiaryThreeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryThreeMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryFourMember" xlink:label="loc_cneySubsidiaryFourMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryFourMember" order="1024" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryFiveMember" xlink:label="loc_cneySubsidiaryFiveMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryFiveMember" order="1025" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiarySixMember" xlink:label="loc_cneySubsidiarySixMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiarySixMember" order="1026" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiarySevenMember" xlink:label="loc_cneySubsidiarySevenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiarySevenMember" order="1027" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryEightMember" xlink:label="loc_cneySubsidiaryEightMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryEightMember" order="1028" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryNineMember" xlink:label="loc_cneySubsidiaryNineMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryNineMember" order="1029" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SubsidiaryTenMember" xlink:label="loc_cneySubsidiaryTenMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneySubsidiaryTenMember" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionNameOfAcquiredEntity" xlink:label="loc_us-gaapBusinessAcquisitionNameOfAcquiredEntity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapBusinessAcquisitionNameOfAcquiredEntity" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionDateOfAcquisitionAgreement1" xlink:label="loc_us-gaapBusinessAcquisitionDateOfAcquisitionAgreement1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapBusinessAcquisitionDateOfAcquisitionAgreement1" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="loc_us-gaapBusinessAcquisitionPercentageOfVotingInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapBusinessAcquisitionPercentageOfVotingInterestsAcquired" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_BusinessAcquisitionPercentageOfVotingsInterestsAcquired" xlink:label="loc_cneyBusinessAcquisitionPercentageOfVotingsInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyBusinessAcquisitionPercentageOfVotingsInterestsAcquired" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PlaceOfIncorporation" xlink:label="loc_cneyPlaceOfIncorporation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPlaceOfIncorporation" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionDescriptionOfAcquiredEntity" xlink:label="loc_us-gaapBusinessAcquisitionDescriptionOfAcquiredEntity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapBusinessAcquisitionDescriptionOfAcquiredEntity" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OrganizationAndNatureOfBusinessDetailsNarrative" xlink:title="995595 - Disclosure - Organization and nature of business (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1070" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaapBusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapBusinessAcquisitionAxis" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaapBusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapBusinessAcquisitionAxis" xlink:to="loc_us-gaapBusinessAcquisitionAcquireeDomain" order="1070" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaapBusinessAcquisitionAcquireeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapBusinessAcquisitionAxis" xlink:to="loc_us-gaapBusinessAcquisitionAcquireeDomain_10" order="1080" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ShareTransferAgreementMember" xlink:label="loc_cneyShareTransferAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyShareTransferAgreementMember" order="1061" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchaseAgreementMember" xlink:label="loc_cneyPurchaseAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyPurchaseAgreementMember" order="1062" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_YnongMember" xlink:label="loc_cneyYnongMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_cneyYnongMember" order="1063" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember" order="1064" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PathenbotMember" xlink:label="loc_cneyPathenbotMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneyPathenbotMember" order="1065" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_TanmulaiMember" xlink:label="loc_cneyTanmulaiMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapBusinessAcquisitionAcquireeDomain" xlink:to="loc_cneyTanmulaiMember" order="1066" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AgreementDescription" xlink:label="loc_cneyAgreementDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAgreementDescription" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CashPayableByEntityToSeller" xlink:label="loc_cneyCashPayableByEntityToSeller" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyCashPayableByEntityToSeller" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockValue" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaapSharesIssuedPricePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesIssuedPricePerShare" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableGross" xlink:label="loc_us-gaapAccountsReceivableGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableGross" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SharesClosedForIssuanceOfOrdinarySharesInExchange" xlink:label="loc_cneySharesClosedForIssuanceOfOrdinarySharesInExchange" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneySharesClosedForIssuanceOfOrdinarySharesInExchange" order="7" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForAcquisitionAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForAcquisitionShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForAcquisitionShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForAcquisitionShares" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired" xlink:label="loc_us-gaapBusinessAcquisitionPercentageOfVotingInterestsAcquired" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapBusinessAcquisitionPercentageOfVotingInterestsAcquired" order="10" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetails" xlink:title="995596 - Disclosure - Summary of significant accounting policies (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaapMachineryAndEquipmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapMachineryAndEquipmentMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VehiclesMember" xlink:label="loc_us-gaapVehiclesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapVehiclesMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_MinimumOneMember" xlink:label="loc_cneyMinimumOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyMinimumOneMember" order="1033" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OfficeEquipmentMember" xlink:label="loc_us-gaapOfficeEquipmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapOfficeEquipmentMember" order="1034" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_MaximumOneMember" xlink:label="loc_cneyMaximumOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyMaximumOneMember" order="1035" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PropertyPlantAndEquipmentUsefulLifeOfAssets" xlink:label="loc_cneyPropertyPlantAndEquipmentUsefulLifeOfAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPropertyPlantAndEquipmentUsefulLifeOfAssets" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetails1" xlink:title="995597 - Disclosure - Summary of significant accounting policies (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:title="995598 - Disclosure - Summary of significant accounting policies (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccountsReceivableNetDetails" xlink:title="995599 - Disclosure - Accounts receivable net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccountsReceivableNetDetails1" xlink:title="995600 - Disclosure - Accounts receivable net (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/InventoriesNetDetails" xlink:title="995601 - Disclosure - Inventories net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/InventoriesNetDetails1" xlink:title="995602 - Disclosure - Inventories net (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AdvancesToSuppliersNetDetails" xlink:title="995603 - Disclosure - Advances to suppliers net (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AdvancesToSuppliersNetDetails1" xlink:title="995604 - Disclosure - Advances to suppliers net (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OtherReceivableDetails" xlink:title="995605 - Disclosure - Other receivable (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OtherReceivableDetails1" xlink:title="995606 - Disclosure - Other receivable (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/OtherReceivableDetailsNarrative" xlink:title="995607 - Disclosure - Other receivable (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LoanToAThirdPartyDetails" xlink:title="995608 - Disclosure - Loan to a third party (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LoanToAThirdPartyDetailsNarrative" xlink:title="995609 - Disclosure - Loan to a third party (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateAxis" xlink:label="loc_us-gaapAwardDateAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapAwardDateAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_JanuaryTwentyNineTwoZeroTwentySixMember" xlink:label="loc_cneyJanuaryTwentyNineTwoZeroTwentySixMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAwardDateDomain" xlink:to="loc_cneyJanuaryTwentyNineTwoZeroTwentySixMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LoansAgreementDescriptionOfVariableRateDuringPeriod" xlink:label="loc_cneyLoansAgreementDescriptionOfVariableRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLoansAgreementDescriptionOfVariableRateDuringPeriod" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromRepaymentOfLoansAndAdvances" xlink:label="loc_cneyProceedsFromRepaymentOfLoansAndAdvances" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromRepaymentOfLoansAndAdvances" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LoanToAThirdPartyAmounted" xlink:label="loc_cneyLoanToAThirdPartyAmounted" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLoanToAThirdPartyAmounted" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_LendingLoanAmountToThirdParty" xlink:label="loc_cneyLendingLoanAmountToThirdParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyLendingLoanAmountToThirdParty" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:label="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" order="5" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AcquisitionReversalReceivableDetailsNarrative" xlink:title="995610 - Disclosure - Acquisition reversal receivable (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchaseAgreementMember" xlink:label="loc_cneyPurchaseAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyPurchaseAgreementMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherReceivables" xlink:label="loc_us-gaapOtherReceivables" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherReceivables" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestmentsDetails" xlink:title="995611 - Disclosure - Long-term investments (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestmentsDetails1" xlink:title="995612 - Disclosure - Long-term investments (Details 1)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestmentsDetails2" xlink:title="995613 - Disclosure - Long-term investments (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_EquityMethordsInvestmentsMember" xlink:label="loc_cneyEquityMethordsInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyEquityMethordsInvestmentsMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilities" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingExpenses" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LongTermInvestmentsDetailsNarrative" xlink:title="995614 - Disclosure - Long-term investments (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchaseAgreementMember" xlink:label="loc_cneyPurchaseAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyPurchaseAgreementMember" order="1031" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaapCommonClassAMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_us-gaapCommonClassAMember" order="1032" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_EquityMethordsInvestmentsMember" xlink:label="loc_cneyEquityMethordsInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyEquityMethordsInvestmentsMember" order="1033" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_YnongMember" xlink:label="loc_cneyYnongMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_cneyYnongMember" order="1034" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonStockClassASeriesMember" xlink:label="loc_cneyCommonStockClassASeriesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonStockClassASeriesMember" order="1035" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaapIncomeLossFromEquityMethodInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeLossFromEquityMethodInvestments" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AgreementDescription" xlink:label="loc_cneyAgreementDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAgreementDescription" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CashPayableByEntityToSeller" xlink:label="loc_cneyCashPayableByEntityToSeller" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyCashPayableByEntityToSeller" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueAcquisitions" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesAcquisitions" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockValue" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaapSharesIssuedPricePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesIssuedPricePerShare" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableGross" xlink:label="loc_us-gaapAccountsReceivableGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsReceivableGross" order="11" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SharesClosedForIssuanceOfOrdinarySharesInExchange" xlink:label="loc_cneySharesClosedForIssuanceOfOrdinarySharesInExchange" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneySharesClosedForIssuanceOfOrdinarySharesInExchange" order="12" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForAcquisitionAmount" xlink:label="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForAcquisitionAmount" order="13" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForAcquisitionShares" xlink:label="loc_cneyIssuanceOfOrdinarySharesForAcquisitionShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForAcquisitionShares" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments" xlink:label="loc_us-gaapLongTermInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermInvestments" order="15" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PaymentForPurchaseOfTreasuryShares" xlink:label="loc_cneyPaymentForPurchaseOfTreasuryShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPaymentForPurchaseOfTreasuryShares" order="16" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ShareOfNetLossFromEquityInvestee" xlink:label="loc_cneyShareOfNetLossFromEquityInvestee" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyShareOfNetLossFromEquityInvestee" order="17" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_RemainingAcquisitionConsiderationPayable" xlink:label="loc_cneyRemainingAcquisitionConsiderationPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyRemainingAcquisitionConsiderationPayable" order="18" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/BiologicalAssetsDetails" xlink:title="995615 - Disclosure - Biological assets (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/BiologicalAssetsDetailsNarrative" xlink:title="995616 - Disclosure - Biological assets (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/PropertyAndEquipmentNetDetails" xlink:title="995617 - Disclosure - Property and equipment net (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaapMachineryAndEquipmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapMachineryAndEquipmentMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VehiclesMember" xlink:label="loc_us-gaapVehiclesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapVehiclesMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LandAndBuildingMember" xlink:label="loc_us-gaapLandAndBuildingMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapLandAndBuildingMember" order="1013" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaapPropertyPlantAndEquipmentGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentGross" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/PropertyAndEquipmentNetDetailsNarrative" xlink:title="995618 - Disclosure - Property and equipment net (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LandUseRightNetDetails" xlink:title="995619 - Disclosure - Land use right net (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UseRightsMember" xlink:label="loc_us-gaapUseRightsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapFiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="loc_us-gaapUseRightsMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsGross" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsAccumulatedAmortization" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsAccumulatedAmortization" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaapFiniteLivedIntangibleAssetsNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapFiniteLivedIntangibleAssetsNet" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LandUseRightNetDetailsNarrative" xlink:title="995620 - Disclosure - Land use right net (Details Narrative)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConvertibleNoteDetailsNarrative" xlink:title="995621 - Disclosure - Convertible note (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonStockClassASeriesMember" xlink:label="loc_cneyCommonStockClassASeriesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonStockClassASeriesMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseLongTermDebt" xlink:label="loc_us-gaapInterestExpenseLongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapInterestExpenseLongTermDebt" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConvertibleNoteUnsecured" xlink:label="loc_cneyConvertibleNoteUnsecured" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConvertibleNoteUnsecured" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromConvertibleDebtConvertedToEquity" xlink:label="loc_cneyProceedsFromConvertibleDebtConvertedToEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromConvertibleDebtConvertedToEquity" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DebtInstrumentDiscount" xlink:label="loc_cneyDebtInstrumentDiscount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDebtInstrumentDiscount" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DebtIssuanceCosts" xlink:label="loc_cneyDebtIssuanceCosts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDebtIssuanceCosts" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:label="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConversionOfConvertibleNotePerShare" xlink:label="loc_cneyConversionOfConvertibleNotePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConversionOfConvertibleNotePerShare" order="7" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SaleLeasebackTransactionsRentExpense" xlink:label="loc_cneySaleLeasebackTransactionsRentExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneySaleLeasebackTransactionsRentExpense" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AggregatePurchasePrice" xlink:label="loc_cneyAggregatePurchasePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAggregatePurchasePrice" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" order="10" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_RedemptionOfConvertibleNote" xlink:label="loc_cneyRedemptionOfConvertibleNote" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyRedemptionOfConvertibleNote" order="11" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AdditionalShareIssued" xlink:label="loc_cneyAdditionalShareIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAdditionalShareIssued" order="12" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:title="995622 - Disclosure - Accrued expenses and other current liabilities (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/RelatedPartyTransactionsDetailsNarrative" xlink:title="995623 - Disclosure - Related party transactions (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermAxis" xlink:label="loc_us-gaapLeaseContractualTermAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapLeaseContractualTermAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain" xlink:label="loc_us-gaapLeaseContractualTermDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapLeaseContractualTermAxis" xlink:to="loc_us-gaapLeaseContractualTermDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain" xlink:label="loc_us-gaapLeaseContractualTermDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapLeaseContractualTermAxis" xlink:to="loc_us-gaapLeaseContractualTermDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_HangzhouForasenTechnologyCoLtdMember" xlink:label="loc_cneyHangzhouForasenTechnologyCoLtdMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLeaseContractualTermDomain" xlink:to="loc_cneyHangzhouForasenTechnologyCoLtdMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_YefangZhangMember" xlink:label="loc_cneyYefangZhangMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_cneyYefangZhangMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AnnualRentAmount" xlink:label="loc_cneyAnnualRentAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAnnualRentAmount" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DueToRelatedPartyAmount" xlink:label="loc_cneyDueToRelatedPartyAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDueToRelatedPartyAmount" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_TermOfTheLease" xlink:label="loc_cneyTermOfTheLease" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyTermOfTheLease" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AmountOfDirectLoan" xlink:label="loc_cneyAmountOfDirectLoan" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAmountOfDirectLoan" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IndirectDebtFromRelatedPartyAmount" xlink:label="loc_cneyIndirectDebtFromRelatedPartyAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIndirectDebtFromRelatedPartyAmount" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AreaOfLand" xlink:label="loc_us-gaapAreaOfLand" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAreaOfLand" order="6" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ShareholdersEquityDetailsNarrative" xlink:title="995624 - Disclosure - Shareholders equity (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:label="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srtEquityMethodInvesteeNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:to="loc_srtEquityMethodInvesteeNameDomain" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srtEquityMethodInvesteeNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:to="loc_srtEquityMethodInvesteeNameDomain_10" order="1050" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaapRelatedPartyTransactionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapRelatedPartyTransactionAxis" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain" order="1060" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaapRelatedPartyTransactionDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapRelatedPartyTransactionAxis" xlink:to="loc_us-gaapRelatedPartyTransactionDomain_10" order="1070" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonStockClassASeriesMember" xlink:label="loc_cneyCommonStockClassASeriesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonStockClassASeriesMember" order="1051" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonStockClassBSeriesMember" xlink:label="loc_cneyCommonStockClassBSeriesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonStockClassBSeriesMember" order="1052" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CnEnergyMember" xlink:label="loc_cneyCnEnergyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtEquityMethodInvesteeNameDomain" xlink:to="loc_cneyCnEnergyMember" order="1053" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_BottomMember" xlink:label="loc_cneyBottomMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyBottomMember" order="1054" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_TopMember" xlink:label="loc_cneyTopMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyTopMember" order="1055" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_YnongGroupMember" xlink:label="loc_cneyYnongGroupMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionDomain" xlink:to="loc_cneyYnongGroupMember" order="1056" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassAPurchaseAgreementMember" xlink:label="loc_cneyClassAPurchaseAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyClassAPurchaseAgreementMember" order="1057" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ClassBPurchaseAgreementMember" xlink:label="loc_cneyClassBPurchaseAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyClassBPurchaseAgreementMember" order="1058" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesAcquisitions" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueAcquisitions" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConvertibleNoteUnsecured" xlink:label="loc_cneyConvertibleNoteUnsecured" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConvertibleNoteUnsecured" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromConvertibleDebtConvertedToEquity" xlink:label="loc_cneyProceedsFromConvertibleDebtConvertedToEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromConvertibleDebtConvertedToEquity" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesNewIssues" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaapSharesIssuedPricePerShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesIssuedPricePerShare" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PurchasePrice" xlink:label="loc_cneyPurchasePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPurchasePrice" order="7" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DebtInstrumentDiscount" xlink:label="loc_cneyDebtInstrumentDiscount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDebtInstrumentDiscount" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SaleLeasebackTransactionsRentExpense" xlink:label="loc_cneySaleLeasebackTransactionsRentExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneySaleLeasebackTransactionsRentExpense" order="9" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DebtIssuanceCosts" xlink:label="loc_cneyDebtIssuanceCosts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDebtIssuanceCosts" order="10" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AggregatePurchasePrice" xlink:label="loc_cneyAggregatePurchasePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAggregatePurchasePrice" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod" xlink:label="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateDuringPeriod" order="12" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" order="13" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_RedemptionOfConvertibleNote" xlink:label="loc_cneyRedemptionOfConvertibleNote" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyRedemptionOfConvertibleNote" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ExcessStockSharesIssued" xlink:label="loc_us-gaapExcessStockSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapExcessStockSharesIssued" order="15" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AdditionalShareIssued" xlink:label="loc_cneyAdditionalShareIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAdditionalShareIssued" order="16" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding" order="18" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DescriptionOfUnderwritingAgreement" xlink:label="loc_cneyDescriptionOfUnderwritingAgreement" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyDescriptionOfUnderwritingAgreement" order="19" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceInitialPublicOffering" xlink:label="loc_us-gaapProceedsFromIssuanceInitialPublicOffering" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProceedsFromIssuanceInitialPublicOffering" order="20" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_StatutoryReservesAmount" xlink:label="loc_cneyStatutoryReservesAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyStatutoryReservesAmount" order="21" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PreFundedWarrantsOutstanding" xlink:label="loc_cneyPreFundedWarrantsOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPreFundedWarrantsOutstanding" order="22" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_WeightedAverageNumberOfSharesOutstanding" xlink:label="loc_cneyWeightedAverageNumberOfSharesOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyWeightedAverageNumberOfSharesOutstanding" order="23" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_NumberOfPreFundedWarrantsExercised" xlink:label="loc_cneyNumberOfPreFundedWarrantsExercised" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyNumberOfPreFundedWarrantsExercised" order="24" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaapClassOfWarrantOrRightOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapClassOfWarrantOrRightOutstanding" order="25" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" order="26" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightUnissued" xlink:label="loc_us-gaapClassOfWarrantOrRightUnissued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapClassOfWarrantOrRightUnissued" order="27" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_NumberOfClassOfWarrantOrRightExercised" xlink:label="loc_cneyNumberOfClassOfWarrantOrRightExercised" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyNumberOfClassOfWarrantOrRightExercised" order="28" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/TaxesDetails" xlink:title="995625 - Disclosure - Taxes (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/TaxesDetails1" xlink:title="995626 - Disclosure - Taxes (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaapTypeOfArrangementAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapTypeOfArrangementAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProvisionForIncomeTaxMember" xlink:label="loc_cneyProvisionForIncomeTaxMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:to="loc_cneyProvisionForIncomeTaxMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:label="loc_us-gaapCurrentIncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCurrentIncomeTaxExpenseBenefit" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="loc_us-gaapDeferredIncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDeferredIncomeTaxExpenseBenefit" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit" order="3" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/TaxesDetails2" xlink:title="995627 - Disclosure - Taxes (Details 2)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/TaxesDetailsNarrative" xlink:title="995628 - Disclosure - Taxes (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="loc_us-gaapOperatingLossCarryforwards" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLossCarryforwards" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsForeign" xlink:label="loc_us-gaapEffectiveIncomeTaxRateReconciliationTaxCreditsForeign" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapEffectiveIncomeTaxRateReconciliationTaxCreditsForeign" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_EnterpriseIncomeTax" xlink:label="loc_cneyEnterpriseIncomeTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyEnterpriseIncomeTax" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ValuationAllowanceOfDeferredtaxAssets" xlink:label="loc_cneyValuationAllowanceOfDeferredtaxAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyValuationAllowanceOfDeferredtaxAssets" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaapValuationAllowanceDeferredTaxAssetChangeInAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapValuationAllowanceDeferredTaxAssetChangeInAmount" order="5" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/ConcentrationOfMajorCustomersAndSuppliersDetailsNarrative" xlink:title="995629 - Disclosure - Concentration of major customers and suppliers (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaapConcentrationRiskByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapConcentrationRiskByTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaapConcentrationRiskByBenchmarkAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapConcentrationRiskByBenchmarkAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CustomerOneMember" xlink:label="loc_cneyCustomerOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneyCustomerOneMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CustomerTwoMember" xlink:label="loc_cneyCustomerTwoMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneyCustomerTwoMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CustomerThreeMember" xlink:label="loc_cneyCustomerThreeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneyCustomerThreeMember" order="1043" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableMember" xlink:label="loc_us-gaapAccountsReceivableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_us-gaapAccountsReceivableMember" order="1044" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CustomerFourMember" xlink:label="loc_cneyCustomerFourMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneyCustomerFourMember" order="1045" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SupplierOneMember" xlink:label="loc_cneySupplierOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneySupplierOneMember" order="1046" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SupplierTwoMember" xlink:label="loc_cneySupplierTwoMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneySupplierTwoMember" order="1047" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SupplierThreeMember" xlink:label="loc_cneySupplierThreeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_cneySupplierThreeMember" order="1048" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConcentrationRiskPercentageOne" xlink:label="loc_cneyConcentrationRiskPercentageOne" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConcentrationRiskPercentageOne" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LeasesDetails" xlink:title="995630 - Disclosure - Leases (Details)" />
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/LeasesDetailsNarrative" xlink:title="995631 - Disclosure - Leases (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermAxis" xlink:label="loc_us-gaapLeaseContractualTermAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapLeaseContractualTermAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain" xlink:label="loc_us-gaapLeaseContractualTermDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapLeaseContractualTermAxis" xlink:to="loc_us-gaapLeaseContractualTermDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseContractualTermDomain" xlink:label="loc_us-gaapLeaseContractualTermDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapLeaseContractualTermAxis" xlink:to="loc_us-gaapLeaseContractualTermDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_HangzhouForasenTechnologyCoLtdMember" xlink:label="loc_cneyHangzhouForasenTechnologyCoLtdMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLeaseContractualTermDomain" xlink:to="loc_cneyHangzhouForasenTechnologyCoLtdMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseExpense" xlink:label="loc_us-gaapOperatingLeaseExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseExpense" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AreaOfLand" xlink:label="loc_us-gaapAreaOfLand" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAreaOfLand" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidRent" xlink:label="loc_us-gaapPrepaidRent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPrepaidRent" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_WeightedAverageRemainingLeaseTerm" xlink:label="loc_cneyWeightedAverageRemainingLeaseTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyWeightedAverageRemainingLeaseTerm" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent" order="5" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SegmentReportingDetails" xlink:title="995632 - Disclosure - Segment reporting (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaapStatementBusinessSegmentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementBusinessSegmentsAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaapSegmentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementBusinessSegmentsAxis" xlink:to="loc_us-gaapSegmentDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaapSegmentDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementBusinessSegmentsAxis" xlink:to="loc_us-gaapSegmentDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ActivatedCarbonMember" xlink:label="loc_cneyActivatedCarbonMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSegmentDomain" xlink:to="loc_cneyActivatedCarbonMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_BiomassElectricityMember" xlink:label="loc_cneyBiomassElectricityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSegmentDomain" xlink:to="loc_cneyBiomassElectricityMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="1" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CommitmentsAndContingenciesDetailsNarrative" xlink:title="995633 - Disclosure - Commitments and contingencies (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_MinimumOneMember" xlink:label="loc_cneyMinimumOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyMinimumOneMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_MaximumOneMember" xlink:label="loc_cneyMaximumOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyMaximumOneMember" order="1012" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PercentageOfLateFeesPerDay" xlink:label="loc_cneyPercentageOfLateFeesPerDay" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPercentageOfLateFeesPerDay" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyEstimateOfPossibleLoss" xlink:label="loc_us-gaapLossContingencyEstimateOfPossibleLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLossContingencyEstimateOfPossibleLoss" order="2" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/DisposalOfSubsidiariesDetails" xlink:title="995634 - Disclosure - Disposal of subsidiaries (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DispositionOfSubsidiariesMember" xlink:label="loc_cneyDispositionOfSubsidiariesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_cneyDispositionOfSubsidiariesMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Cash" xlink:label="loc_us-gaapCash" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCash" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_BiologicalAssets" xlink:label="loc_cneyBiologicalAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyBiologicalAssets" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Land" xlink:label="loc_us-gaapLand" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLand" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableCurrent" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TaxesPayableCurrent" xlink:label="loc_us-gaapTaxesPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTaxesPayableCurrent" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" xlink:label="loc_us-gaapAccountsPayableAndOtherAccruedLiabilitiesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccountsPayableAndOtherAccruedLiabilitiesCurrent" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilities" order="10" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/DisposalOfSubsidiariesDetails1" xlink:title="995635 - Disclosure - Disposal of subsidiaries (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DispositionOfSubsidiariesMember" xlink:label="loc_cneyDispositionOfSubsidiariesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_cneyDispositionOfSubsidiariesMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues" xlink:label="loc_us-gaapRevenues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRevenues" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaapCostOfRevenue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCostOfRevenue" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaapGrossProfit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGrossProfit" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaapOperatingExpenses" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingExpenses" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaapOperatingIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOperatingIncomeLoss" order="5" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_OtherExpense" xlink:label="loc_cneyOtherExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyOtherExpense" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaapIncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncomeTaxExpenseBenefit" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="9" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/DisposalOfSubsidiariesDetailsNarrative" xlink:title="995636 - Disclosure - Disposal of subsidiaries (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaapPlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapPlanNameAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaapPlanNameDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapPlanNameAxis" xlink:to="loc_us-gaapPlanNameDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_DispositionOfSubsidiariesMember" xlink:label="loc_cneyDispositionOfSubsidiariesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_cneyDispositionOfSubsidiariesMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ShareTransferAgreementMember" xlink:label="loc_cneyShareTransferAgreementMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPlanNameDomain" xlink:to="loc_cneyShareTransferAgreementMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuedAndOutstandingEquityPercentage" xlink:label="loc_cneyIssuedAndOutstandingEquityPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuedAndOutstandingEquityPercentage" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaapPaymentsToAcquireBusinessesGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapPaymentsToAcquireBusinessesGross" order="2" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/SubsequentEventsDetailsNarrative" xlink:title="995637 - Disclosure - Subsequent Events (Details Narrative)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeAxis" xlink:label="loc_us-gaapShortTermDebtTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapShortTermDebtTypeAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermDebtTypeDomain" xlink:label="loc_us-gaapShortTermDebtTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapShortTermDebtTypeAxis" xlink:to="loc_us-gaapShortTermDebtTypeDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaapSubsequentEventTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapSubsequentEventTypeAxis" order="1040" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain" order="1050" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain_10" order="1060" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SecuredPromissoryNoteMember" xlink:label="loc_cneySecuredPromissoryNoteMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShortTermDebtTypeDomain" xlink:to="loc_cneySecuredPromissoryNoteMember" order="1041" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaapSubsequentEventMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventTypeDomain" xlink:to="loc_us-gaapSubsequentEventMember" order="1042" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFeeAmount" xlink:label="loc_us-gaapDebtInstrumentFeeAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentFeeAmount" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateStatedPercentage" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionOriginalDebtAmount1" xlink:label="loc_us-gaapDebtConversionOriginalDebtAmount1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapDebtConversionOriginalDebtAmount1" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LegalFees" xlink:label="loc_us-gaapLegalFees" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLegalFees" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_GrossProceedsAmount" xlink:label="loc_cneyGrossProceedsAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyGrossProceedsAmount" order="5" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PayingInterestOfOutstandingPrincipleAmount" xlink:label="loc_cneyPayingInterestOfOutstandingPrincipleAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPayingInterestOfOutstandingPrincipleAmount" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PossibleFutureConversionsDescription" xlink:label="loc_cneyPossibleFutureConversionsDescription" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPossibleFutureConversionsDescription" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails" xlink:title="995638 - Disclosure - Condensed financial information of the parent company (Details)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaapStatementClassOfStockAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementClassOfStockAxis" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain" order="1030" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaapClassOfStockDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaapStatementClassOfStockAxis" xlink:to="loc_us-gaapClassOfStockDomain_10" order="1040" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember" order="1021" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonShareClassAMember" xlink:label="loc_cneyCommonShareClassAMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonShareClassAMember" order="1022" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CommonShareClassBMember" xlink:label="loc_cneyCommonShareClassBMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapClassOfStockDomain" xlink:to="loc_cneyCommonShareClassBMember" order="1023" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Cash" xlink:label="loc_us-gaapCash" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCash" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AcquisitionReversalReceivableCurrent" xlink:label="loc_cneyAcquisitionReversalReceivableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAcquisitionReversalReceivableCurrent" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsCurrent" xlink:label="loc_us-gaapOtherAssetsCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherAssetsCurrent" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermInvestments" xlink:label="loc_us-gaapLongTermInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLongTermInvestments" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherInvestments" xlink:label="loc_us-gaapOtherInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherInvestments" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAssets" order="6" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ConvertibleLongTermNotePayable" xlink:label="loc_cneyConvertibleLongTermNotePayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyConvertibleLongTermNotePayable" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLiabilitiesCurrent" order="8" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_RemainingAcquisitionConsiderationPayable" xlink:label="loc_cneyRemainingAcquisitionConsiderationPayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyRemainingAcquisitionConsiderationPayable" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilities" xlink:label="loc_us-gaapOtherLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherLiabilities" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAdditionalPaidInCapital" order="12" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_StatutoryReservesValue" xlink:label="loc_cneyStatutoryReservesValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyStatutoryReservesValue" order="13" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit" order="14" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity" order="16" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity" order="17" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCommonStockValue" order="18" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails1" xlink:title="995639 - Disclosure - Condensed financial information of the parent company (Details 1)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ParentCompanyOneMember" xlink:label="loc_cneyParentCompanyOneMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_cneyParentCompanyOneMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaapGeneralAndAdministrativeExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGeneralAndAdministrativeExpense" order="1" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainOrLossOnSaleOfStockInSubsidiary" xlink:label="loc_us-gaapGainOrLossOnSaleOfStockInSubsidiary" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapGainOrLossOnSaleOfStockInSubsidiary" order="2" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TemporaryEquityInterestInSubsidiaryEarnings" xlink:label="loc_us-gaapTemporaryEquityInterestInSubsidiaryEarnings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTemporaryEquityInterestInSubsidiaryEarnings" order="3" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss" order="4" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProfitLoss" order="5" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossNetOfTax" order="7" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://cney.com/role/CondensedFinancialInformationOfTheParentCompanyDetails2" xlink:title="995640 - Disclosure - Condensed financial information of the parent company (Details 2)">
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" order="2000" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_srtConsolidatedEntitiesAxis" order="1010" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" order="1020" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" order="1030" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ParentCompanyMember" xlink:label="loc_srtParentCompanyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtParentCompanyMember" order="1011" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaapProfitLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProfitLoss" order="1" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AllowanceForPrepaidExpensesAndOtherCurrentAssets" xlink:label="loc_cneyAllowanceForPrepaidExpensesAndOtherCurrentAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAllowanceForPrepaidExpensesAndOtherCurrentAssets" order="2" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_GainLossOnDisposalOfSubsidiaries" xlink:label="loc_cneyGainLossOnDisposalOfSubsidiaries" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyGainLossOnDisposalOfSubsidiaries" order="3" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_AmortizationOfFinancingCostAndDiscount" xlink:label="loc_cneyAmortizationOfFinancingCostAndDiscount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyAmortizationOfFinancingCostAndDiscount" order="4" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForCommitmentFee" xlink:label="loc_cneyIssuanceOfOrdinarySharesForCommitmentFee" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForCommitmentFee" order="5" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_InterestExpensesOther" xlink:label="loc_cneyInterestExpensesOther" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyInterestExpensesOther" order="6" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="loc_us-gaapAmortizationOfFinancingCostsAndDiscounts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapAmortizationOfFinancingCostsAndDiscounts" order="7" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IssuanceOfStockAndWarrantsForServicesOrClaims" xlink:label="loc_us-gaapIssuanceOfStockAndWarrantsForServicesOrClaims" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIssuanceOfStockAndWarrantsForServicesOrClaims" order="8" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TemporaryEquityInterestInSubsidiaryEarnings" xlink:label="loc_us-gaapTemporaryEquityInterestInSubsidiaryEarnings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapTemporaryEquityInterestInSubsidiaryEarnings" order="9" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaapIncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" order="10" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" xlink:label="loc_us-gaapIncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapIncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" order="11" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInOperatingActivities" order="12" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromPaymentOfOtherReceivables" xlink:label="loc_cneyProceedsFromPaymentOfOtherReceivables" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromPaymentOfOtherReceivables" order="13" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_PaymentForPurchaseOfTreasuryShares" xlink:label="loc_cneyPaymentForPurchaseOfTreasuryShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyPaymentForPurchaseOfTreasuryShares" order="14" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_InvestmentInSubsidiaries" xlink:label="loc_cneyInvestmentInSubsidiaries" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyInvestmentInSubsidiaries" order="15" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInInvestingActivities" order="16" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForPrivatePlacement" xlink:label="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacement" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForPrivatePlacement" order="17" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromConvertibleNotes" xlink:label="loc_cneyProceedsFromConvertibleNotes" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromConvertibleNotes" order="18" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_ProceedsFromWarrantsExercised" xlink:label="loc_cneyProceedsFromWarrantsExercised" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyProceedsFromWarrantsExercised" order="19" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromRelatedPartyDebt" xlink:label="loc_us-gaapProceedsFromRelatedPartyDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapProceedsFromRelatedPartyDebt" order="20" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetCashProvidedByUsedInFinancingActivities" order="21" />
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" order="22" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalent" xlink:label="loc_cneyCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalent" order="23" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_SharesIssuedForAcquisition" xlink:label="loc_cneySharesIssuedForAcquisition" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneySharesIssuedForAcquisition" order="25" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForConvertibleNotesRedemption" xlink:label="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemption" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForConvertibleNotesRedemption" order="26" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinaryShareForCommitmentFee" xlink:label="loc_cneyIssuanceOfOrdinaryShareForCommitmentFee" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinaryShareForCommitmentFee" order="27" />
    <link:loc xlink:type="locator" xlink:href="cney-20250930.xsd#cney_IssuanceOfOrdinarySharesForServices" xlink:label="loc_cneyIssuanceOfOrdinarySharesForServices" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_cneyIssuanceOfOrdinarySharesForServices" order="28" />
  </link:definitionLink>
</link:linkbase>
