Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenue and cost of goods sold
Hydrocarbon revenue	$ 90	$ 298
Grant and other revenue	32	265
Total revenues	5,616	6,320
Cost of goods sold	9,408	9,223
Gross loss	(3,792)	(2,903)
Operating expenses
Research and development expense	1,217	1,044
Selling, general and administrative expense	2,173	1,919
Total operating expenses	3,390	2,963
Loss from operations	(7,182)	(5,866)
Other (expense) income
Interest expense	(714)	(2,151)
(Loss) on exchange or conversion of debt	(964)
(Loss) from change in fair value of the 2017 Notes	(339)	(836)
Gain from change in fair value of derivative warrant liability	3,259	5,248
Other income	6
Total other expense, net	1,248	2,261
Net loss	$ (5,934)	$ (3,605)
Net loss per share - basic and diluted	$ (0.51)	$ (3.13)
Weighted-average number of common shares outstanding - basic and diluted	11,584,595	1,150,817
Ethanol
Revenue and cost of goods sold
Sales	$ 5,494	$ 5,757