Form 8-K

8-K — TECOGEN INC.

Accession: 0001537435-26-000092

Filed: 2026-10-14

Period: 2026-10-14

CIK: 0001537435

SIC: 3585 (AIR COND & WARM AIR HEATING EQUIP & COMM & INDL REFRIG EQUIP)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tgen-20261014.htm (Primary)

EX-99.1 (tecogenpressreleaserecus.htm)

EX-99.2 (cloudsmarttestimonial.htm)

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8-K

8-K (Primary)

Filename: tgen-20261014.htm · Sequence: 1

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FALSE000153743500015374352024-05-092024-05-09

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

__________________________

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): October 14, 2026

TECOGEN INC.

(Exact Name of Registrant as Specified in Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

001-36103 04-3536131

(Commission File Number) (IRS Employer Identification No.)

76 Treble Cove Road, Building 1

North Billerica, Massachusetts 01862

(Address of Principal Executive Offices and Zip Code)

(781) 466-6400

(Registrant's telephone number, including area code)

Securities registered or to be registered pursuant to Section 12(b) of the Act.

Title of each class Trading Symbol Name of exchange on which registered

Common Stock, $0.001 par value per share TGEN NYSE American, LLC

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

INFORMATION TO BE INCLUDED IN THE REPORT

Section 8 - Other Events

Item 8.01. Other Events.

On October 14, 2026, Tecogen Inc., a Delaware corporation (the “Company”), issued the attached press release regarding a customer testimonial from Cloudsmart, Inc., a Cloud and AI data center in Connecticut. The press release describes Cloudsmart’s use of the Company’s InVerde cogeneration system at Cloudsmart’s data center to reduce energy costs. The press release highlights Cloudsmart’s satisfaction with the service provided by the Company and the performance of the Company’s cogeneration equipment in a demanding data center environment.

The Company’s press release dated October 14, 2026, and Cloudsmart’s customer testimonial are attached hereto as Exhibits 99.1 and 99.2.

Section 9 - Financial Statements and Exhibits

Item 9.01. Financial Statements and Exhibits

Exhibit No. Exhibit Description

99.1 Tecogen Inc. Press Release dated October 14, 2026

99.2 Cloudsmart, Inc. Customer Testimonial

Filed herewith

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Company has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.

TECOGEN INC.

By: /s/ Abinand Rangesh

October 14, 2026 Abinand Rangesh, Chief Executive Officer

Principal Executive Officer

EX-99.1

Filename: tecogenpressreleaserecus.htm · Sequence: 2

tecogenpressreleaserecus

On Wednesday, October 14, 2026 at 10:00AM ET Data Center Cuts Electric Bills Substantially with Tecogen's InVerde BILLERICA, MA / ACCESS Newswire / October 14, 2026 / Tecogen Inc. (NYSE American:TGEN) is pleased share a recent data center customer testimonial. Robyn Sullivan, CEO and President of Cloudsmart Inc, a Tier 3, SOC 2, Cloud and AI data center in Connecticut said, "For a few months now, we have been creating our own power with Tecogen Inc.'s InVerde and we're glad we did." "We cut our electric bills substantially, which gives us an edge against other local data centers. Whenever we give potential customers a tour, they are not only intrigued, but love that we can offer lower energy costs and greener power sources. Since starting it up, the unit has run reliably and has been hands-off as their service team has taken care of everything." Abinand Rangesh, CEO of Tecogen commented "We are thrilled that Cloudsmart chose our InVerde for this data center. As this positive testimonial shows, our products are not only generating tremendous savings but are also able to meet the demanding needs of a data center environment. Such real-world proof points are essential to convert our data center pipeline to orders." About Tecogen Tecogen designs, manufactures, sells, installs, and maintains high efficiency, ultra-clean, cogeneration products including engine- driven combined heat and power, air conditioning systems, and high-efficiency water heaters for residential, commercial, recreational and industrial use. The company provides cost effective, environmentally friendly and reliable products for energy production that nearly eliminate criteria pollutants and significantly reduce a customer's carbon footprint. In business for over 35 years, Tecogen has shipped more than 3,200 units, supported by an established network of engineering, sales, and service personnel in key markets in North America. For more information, please visit www.tecogen.com or contact us for a free Site Assessment. Forward Looking Statements This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, Section 21E of the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995 and other federal securities laws that involve a number of risks and uncertainties. Forward-looking statements generally can be identified by the use of forward-looking terminology such as "believe," "expect," "anticipate," "intend," "plan," "estimate," "project," "target," "potential," "will," "should," "seek," "could," "likely," "may," "pro forma," "anticipate," "continue," or other variations thereof (including their use in the negative), or by discussions of strategies, plans or intentions. All statements, other than statements of historical fact included in this press release regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects and plans and objectives of management are forward-looking statements. These statements are only predictions and involve known and unknown risks, uncertainties, and other factors that may cause our actual results to differ materially from those expressed or implied by such forward-looking statements. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Forward-looking statements speak only as of the date on which they are made, and we undertake no obligation to update or revise any forward-looking statements. In addition to those factors described in our Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q and in our Form 8-K, under "Risk Factors," among the factors that could cause actual results to differ materially from past and projected future results are the following: fluctuations in demand for our products and services, competing technological developments, issues relating to research and development, the availability of incentives, rebates, and tax benefits relating to our products and services, changes in the regulatory environment relating to our products and services, integration of acquired business operations, and the ability to obtain financing on favorable terms to fund existing operations and anticipated growth. Tecogen Media & Investor Relations Contact Information: Abinand Rangesh, CEO P: 781-466-6487 E: Abinand.Rangesh@tecogen.com SOURCE: Tecogen, Inc.

EX-99.2

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cloudsmarttestimonial

Cloudsmart, Inc.’s Post Cloudsmart, Inc. 239 followers 1d · Edited 15 Like Comment To view or add a comment, sign in For a few months now we have been creating our own power with Tecogen Inc.'s InVerde and we're glad we did. We cut our electric bills substantially which gives us an edge against other local data centers. Whenever we give potential customers a tour, they are not only intrigued, but love that we can offer lower energy costs and greener power sources. Since starting it up, the unit has run reliably and has been hands-off as their service team has taken care of everything. Share Top Content People Learning Jobs Games Get the app

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