v3.26.1
Organization and nature of business (Details)
 12 Months Ended
Sep. 30, 2025
Subsidiary One [Member]  
Name of Entity CN Energy
Date of Incoporation Nov. 23, 2018
Percentage of Ownership Parent
Place of Incorporation British Virgin Islands
Principal Activities Holding company
Subsidiary Two [Member]  
Name of Entity Ewforest
Date of Incoporation Nov. 29, 2024
Percentage of Ownership 100.00%
Place of Incorporation Hong Kong, China
Principal Activities Holding company
Subsidiary Three [Member]  
Name of Entity CN Energy USA Inc.
Date of Incoporation Mar. 31, 2022
Percentage of Ownership 100.00%
Place of Incorporation Delaware, U.S.A
Principal Activities Inactive
Subsidiary Four [Member]  
Name of Entity MZ HK
Date of Incoporation Dec. 06, 2018
Percentage of Ownership 100.00%
Place of Incorporation Hong Kong, China
Principal Activities Holding company
Subsidiary Five [Member]  
Name of Entity MZ Pintai
Date of Incoporation Jan. 22, 2019
Percentage of Ownership 100.00%
Place of Incorporation Zhejiang, China
Principal Activities Holding company
Subsidiary Six [Member]  
Name of Entity Zhejiang New Material
Date of Incoporation May 24, 2021
Percentage of Ownership 100.00%
Place of Incorporation Zhejiang, China
Principal Activities Produce and sell Activated Carbon
Subsidiary Seven [Member]  
Name of Entity Zhoushan Xinyue
Date of Incoporation Apr. 08, 2022
Percentage of Ownership 100.00%
Place of Incorporation Zhejiang, China
Principal Activities Trading
Subsidiary Eight [Member]  
Name of Entity Tanmulai
Date of Incoporation Jul. 02, 2025
Percentage of Ownership 100.00%
Place of Incorporation Zhejiang, China
Principal Activities Trading
Subsidiary Nine [Member]  
Name of Entity Yunnan Yuemu
Date of Incoporation Sep. 02, 2022
Percentage of Ownership 100.00%
Place of Incorporation Yunnan, China
Principal Activities Holding company
Subsidiary Ten [Member]  
Name of Entity Pathenbot
Date of Incoporation Jul. 02, 2025
Percentage of Ownership 100.00%
Place of Incorporation California, U.S.A.
Principal Activities Active