Note 13 – Convertible note

1．On October 10, 2024, CN Energy Group. Inc., a British Virgin Islands company (the “Company”), entered into a securities purchase agreement (the “Purchase Agreement”) with Streeterville Capital, LLC, a Utah limited liability company (the “Investor”), pursuant to which the Company issued to the Investor an unsecured promissory note, on October 10,2024, in the principal amount of $3,149,750 (the “Note”), convertible into Class A ordinary shares, no par value, of the Company (the “Class A Ordinary Shares”), for a purchase price of $2,925,000.

The Note bears interest at a rate of 7% per annum. All outstanding principal and accrued interest on the Note will become due and payable twelve months after the purchase price of the Note is delivered by the Investor to the Company. The Note includes an original issue discount of $204,750.00 along with $20,000.00 for the Investor’s legal fees, accounting costs, due diligence, monitoring, and other transaction costs incurred in connection with the purchase and sale of the Note. The Company may prepay all or a portion of the Note at any time by paying 105% of the outstanding principal balance elected for pre-payment. The Note contains a floor price of $0.10412 for the possible future conversions into Class A Ordinary Shares.

2. On April 4, 2025, CN Energy Group. Inc. (the “Company”), entered into a securities purchase agreement (the “Purchase Agreement”) with Streeterville Capital, LLC, (the “Investor”). Pursuant to the Purchase Agreement, the Investor agreed to purchase from the Company, and the Company agreed to issue and sell to the Investor, securities in the form of one or more pre-paid purchases (the “Pre-Paid Purchases”) with an aggregate purchase amount of up to $20,000,000, for the purchase (the “Purchase Shares”) of Class A ordinary shares of the Company (the “Ordinary Shares”), upon the terms and subject to the limitations and conditions set forth in such Pre-Paid Purchase.

Upon the initial closing under the Purchase Agreement, on April 8, 2025, the Company issued to the Investor an initial Pre-Paid Purchase in the principal amount of $3,230,000, with an original issue discount (the “OID”) of $210,000 and a transaction expense amount of $20,000 (the “Initial Pre-Paid Purchase”). The OID for each subsequent Pre-Paid Purchase after the Initial Pre-Paid Purchase will be seven percent (7%) of the amount set forth in the applicable Request (as defined in the Purchase Agreement) and each subsequent Pre-Paid Purchase will accrue interest at the annual rate of seven percent (7%). Additionally, the Company issued 1,597,444 (or 63,898 after accounted for the effect of the reverse share split) Class A Ordinary Shares to the Investor as a commitment fee.

For the fiscal years ended September 30, 2025, 2024, and 2023, 609,221, 177,067 and 11,996 Class A Ordinary Shares were issued for the redemption of $3.21 million, $2.42 million, and $1.25 million convertible note, respectively, and interest expenses were $168,183, $233,873, and $435,301 respectively.