Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2019

Property, plant and equipment at March 31, 2019 and December 31, 2018 consisted of the following:



	Estimated Useful Life (in Years)	March 31, 2019			December 31, 2018
Energy systems	1 - 15 years	$	4,372,638		$	12,709,990
Machinery and equipment	5 - 7 years	1,391,354			1,355,617
Furniture and fixtures	5 years	222,542			222,542
Computer software	3 - 5 years	192,865			200,626
Leasehold improvements	*	450,792			450,792
		6,630,191			14,939,567
Less - accumulated depreciation and amortization		(2,705,240		)	(3,666,452		)
		$	3,924,951		$	11,273,115

* Lesser of estimated useful life of asset or lease term