Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue and cost of goods sold
Hydrocarbon revenue	$ 1,929	$ 1,694	$ 3,949
Grant and other revenue	671	1,318	768
Total revenues	27,213	30,137	28,266
Cost of goods sold	37,017	38,762	35,582
Gross loss	(9,804)	(8,625)	(7,316)
Operating expenses
Research and development expense	5,216	6,610	14,120
Selling, general and administrative expense	8,965	16,692	18,341
Total operating expenses	14,181	23,302	32,461
Loss from operations	(23,985)	(31,927)	(39,777)
Other (expense) income
Interest expense	(7,837)	(8,243)	(8,255)
Interest expense - debt issue costs			(3,769)
Gain (Loss) on exchange or conversion of debt	(763)	232
Gain (Loss) on extinguishment of warrant liability	(918)	1,775
Gain from change in fair value of embedded derivative of the 2022 Notes			3,470
Gain from change in fair value of derivative warrant liability	1,783	577	6,530
Gain (Loss) from change in fair value of 2017 Notes	(4,204)	3,895	648
Loss on issuance of equity	(1,519)	(2,523)
Other income	215	20	8
Total other (expense) income	(13,243)	(4,267)	(1,368)
Net loss	$ (37,228)	$ (36,194)	$ (41,145)
Net loss per share - basic and diluted	$ (9.68)	$ (51.61)	$ (153.35)
Weighted-average number of common shares outstanding - basic and diluted	3,847,421	701,252	268,308
Ethanol
Revenue and cost of goods sold
Sales	$ 24,613	$ 27,125	$ 23,549