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, 2025 ("2025 Form 10-K") The risks discussed in our 2025 Form 10-K could materially affect our business, financial condition and future results. The risks described in our 2025 Form 10-K and 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 $4,269,176 during the six months ended June 30, 2026, compared to a loss of $2,124,027 in the same period in 2025. 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 $4,269,176 during the six months ended June 30, 2026, compared to a net loss of $2,124,027 in the six months ended June 30, 2025. Historically, we have incurred net losses, including a net loss of $8,244,830 for the year ended December 31, 2025, and, as of June 30, 2026, we had an accumulated deficit of $60,157,825. 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 our profitability. There can be no assurance we will be able to increase our sales and achieve and sustain profitability in the future.