TECOGEN INC.

In addition to the risks described below, you should carefully consider the factors discussed under "Item1A - Risk Factors” in our Annual Report on Form 10-K for our fiscal year ended December 31, 2024 ("2024 Form 10-K") and in our Quarterly Report on Form 10-Q for the quarter ended March 31, 2025 (“March 31, 2025 Form 10-Q”). The risks discussed in our 2024 Form 10-K and in our March 31, 2025 Form 10-Q could materially affect our business, financial condition and future results. The risks described in our 2024 Form 10-K and in our March 31, 2025 Form 10-Q and the risks described below are not the only risks we face. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial also may materially and adversely affect our business, financial condition or operating results.

We incurred a net loss of $2,124,027 during the six months ended June 30, 2025, compared to a loss of $2,643,763 in the same period in 2024. We have a history of incurring losses from our operations and there can be no assurance we will be able to increase our revenues, manage our expenses and cash flows, and become profitable in the future.

We incurred a net loss of $2,124,027 during the six months ended June 30, 2025, compared to a net loss of $2,643,763 in the six months ended June 30, 2024. Historically, we have incurred net losses, including a net loss of $4,760,238 for the year ended December 31, 2024, and, as of June 30, 2025, we had an accumulated deficit of $49,763,921. Our business is capital intensive and, because our products are built to order with customized configurations, the lead time to build and deliver a unit can be significant. We may be required to purchase key components long before we can deliver a unit and receive payment. Changes in customer orders or lack of demand may also impact on our profitability. There can be no assurance we will be able to increase our sales and achieve and sustain profitability in the future. Our cash flows from operations are insufficient to fund our business and, currently, we are reliant upon financing provided by related parties to help fund our operations.

Risks Related to Ownership of Our Securities

As of the end of the period covered by our Quarterly Report on Form 10-Q for the quarter ended June 30, 2025, our principal executive officer and our principal financial officer concluded there is a material weakness in our disclosure controls and procedures and our internal control over financial reporting. If we are unable to remediate these material weaknesses, if management identifies additional material weaknesses in the future, or if we otherwise fail to maintain effective internal controls over financial reporting, we may not be able to accurately or timely report our financial position or results of operations, which may adversely affect our business and stock price or cause our access to the capital markets to be impaired.

Our disclosure controls and procedures are designed to provide reasonable assurance that the control system’s objectives will be met. Our management, including our Chief Executive Officer and Chief Financial Officer, after evaluating the effectiveness of our disclosure controls and procedures, has concluded that our disclosure controls and procedures were not effective as of June 30, 2025, due to a material weakness with respect to a small number of individuals dealing with general controls over information technology.

We are committed to remediating the material weakness identified in internal controls over financial reporting and have begun the process to remediate this material weakness. Our efforts will focus on instituting mitigating controls to address segregation of duties; hiring of additional staff; implementing additional controls to address system access deficiencies; implementing additional controls over business operations; establishing independent review and verification procedures for our vendor and customer master files; enhancing the documentation to support review occurrences and approval procedures; and, commencing regular periodic reviews of our internal controls over financial reporting with our Board of Directors and Audit Committee to address the inadequate risk oversight function and institute procedures to evaluate and report on risks to financial reporting, including the documentation and completion of a comprehensive risk assessment to identify all potential risk areas and evaluate the adequacy of our controls to mitigate these risks.

In addition, on March 11, 2025, we filed a Current Report on Form 8-K to report, among other things, certain changes in the level of compensation for Mr. Panora, our President and COO, and the resignation of Mr. Gehret, our Vice President of Operations. Although Mr. Gehret remained with us as an employee until February 28, 2025, and then as a consultant until his duties were transferred to Mr. Panora, we subsequently determined we did not report Mr. Gehret’s resignation timely in accordance with the requirements of Form 8-K.

Any failure to implement effective internal controls could harm our operating results or cause us to fail to meet our reporting obligations. Inadequate internal controls could also cause investors to lose confidence in our reported financial information, which could have a negative effect on the trading price of our common stock and may require us to incur additional costs to improve our internal control system.

If we identify further deficiencies in our internal control over financial reporting in the future or if we are unable to comply with the demands that will be placed upon us as a public company, including the requirements of Section 404 of the

Sarbanes-Oxley Act, in a timely manner, we may be unable to accurately report our financial results, or report them within the timeframes required by the SEC. We also could become subject to sanctions or investigations by the SEC or other regulatory authorities. In addition, if we are unable to assert that our internal control over financial reporting is effective, investors may lose confidence in the accuracy and completeness of our financial reports, we may face restricted access to the capital markets, and our stock price may be adversely affected.

Our current controls and any new controls that we develop may also become inadequate because of changes in our business, and weaknesses in our disclosure controls and internal control over financial reporting may be discovered in the future. Any failure to develop or maintain effective controls or any difficulties encountered in their implementation or improvement could cause us to fail to meet our reporting obligations, result in a restatement of our financial statements for prior periods, undermine investor confidence in us, and adversely affect the trading price of our common stock.