Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2022

Property, plant and equipment at March 31, 2022 and December 31, 2021 consisted of the following:


	Estimated Useful Life (in Years)	March 31, 2022		December 31, 2021
Energy systems	1 - 15 years	$	3,478,824	$	3,556,488
Machinery and equipment	5 - 7 years	1,506,919		1,463,153
Furniture and fixtures	5 years	196,007		193,698
Computer software	3 - 5 years	192,865		192,865
Leasehold improvements	*	466,789		466,789
		5,841,404		5,872,993
Less - accumulated depreciation and amortization		(4,135,430)		(4,090,049)
		$	1,705,974	$	1,782,944

* Lesser of estimated useful life of asset or lease term