Annual report pursuant to Section 13 and 15(d)

Cover
- Audit Information
- Cover
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of significant accounting policies (Policies)
Notes Tables
Notes Details

Stockholders' equity - Stock Option Activity (Details)

v3.24.1

Stockholders' equity - Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Exercise Price Per Share [Abstract]
Outstanding, Exercise Price Lower Range Limit (usd per share)	$ 0.71	$ 0.71
Outstanding, Exercise Price Upper Range Limit (usd per share)	10.33
Granted, Exercise Price Lower Range Limit (usd per share)	0.88
Granted, Exercise Price Upper Range Limit (usd per share)	1.10	$ 10.33
Canceled and Forfeited, Exercise Price Lower Range Limit (usd per share)	0.71
Canceled and Forfeited, Exercise Price Upper Range Limit (usd per share)	$ 4.50
Tecogen
Stock Options Outstanding [Roll Forward]
Beginning (shares)	3,204,297
Granted (shares)	575,000	761,650
Canceled and forfeited (shares)	(141,175)
Ending (shares)	3,638,122	3,204,297
Exercisable (shares)	1,953,197
Vested and expected to vest (shares)	3,385,353
Weighted Average Exercise Price [Roll Forward]
Beginning (usd per share)	$ 1.61
Granted (usd per share)	0.93
Canceled and forfeited (usd per share)	1.81
Ending (usd per share)	1.49	$ 1.61
Vested and expected to vest (usd per share)	1.53
Exercisable (usd per share)	$ 1.95
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Outstanding, Aggregate Intrinsic Value	$ 127,811	$ 882,074
Exercisable, Aggregate Intrinsic Value	77,961
Vested and expected to vest, Aggregate Intrinsic Value	$ 120,333
Exercise Price Per Share [Abstract]
Granted, Exercise Price Lower Range Limit (usd per share)		$ 1.10
Stock Options \| Tecogen
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Outstanding, Weighted Average Remaining Life	6 years 8 months 12 days	7 years 3 months 18 days

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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