Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statements (Nos. 333-218244 and 333-187928) on Form S-8 and the Registration Statements (Nos. 333-199634, 333-205147 and 333-212433) on Form S-3 of Tecogen Inc. of our report dated March 12, 2020, relating to the consolidated financial statements of Tecogen Inc., appearing in the 2019 Annual Report on Form 10-K of Tecogen Inc. for the year ended December 31, 2019.

/s/ Wolf & Company, P.C.

Boston, Massachusetts

March 12, 2020