Annual report [Section 13 and 15(d), not S-K Item 405]

Nature of Business and Operations

v3.26.1
Nature of Business and Operations
12 Months Ended
Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Nature of Business and Operations Nature of Business and Operations
Tecogen Inc., a Delaware corporation (together with its subsidiaries "we", "our", "us", "Tecogen," or "Company"), was incorporated on September 15, 2000. We produce commercial and industrial, natural-gas-fueled engine-driven, combined heat and power (CHP) products that reduce energy costs, decrease greenhouse gas emissions and alleviate congestion on the national power grid. Our products supply electric power or mechanical power for cooling, while heat from the engine is recovered and purposefully used at a customer facility. The majority of our customers are located in regions with the highest utility rates, typically California, the Midwest and the Northeast.
Our operations are comprised of three business segments. Our Products segment designs, manufactures and sells industrial and commercial cogeneration systems. Our Services segment provides operation and maintenance services to customers for our products. Our Energy Production segment sells energy in the form of electricity, heat, hot water and cooling to our customers under long-term sales agreements.
On April 30, 2025, we announced that our shares of common stock had been approved for listing on the NYSE American LLC ("NYSE American"), stock exchange. On May 6, 2025, our common stock began trading on the NYSE American under our current symbol "TGEN."
On July 21, 2025, we closed on the sale of an aggregate of 3,985,000 shares of common stock, $0.001 par value per share ("Common Stock"), including an additional 485,000 shares of common stock to cover over-allotments, at a price to the public of $5.00 per share (before deduction of underwriting discounts and commissions), in a firm commitment underwritten public offering pursuant to an underwriting agreement, dated July 18, 2025 between the Company and Roth Capital Partners, LLC as sole underwriter and manager for the offering ("Offering"). The net proceeds from the Offering, after deducting underwriting discounts and commissions and offering expenses were approximately $18,105,100. The net Offering proceeds were as follows:
Gross proceeds $ 19,925,000 
Transaction Costs
Underwriters discounts and commissions 1,394,750 
Legal fees 256,557 
Assurance 83,000 
Original listing fee 75,000 
Filing and other fees 10,593 
Total transaction costs 1,819,900 
Net offering proceeds $ 18,105,100