CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Total operating revenues	$ 1,965	$ 4,528	$ 11,215	$ 12,826
Operating expenses:
Cost of production	2,544	2,480	8,554	8,836
Depreciation and amortization	3,494	4,994	12,222	14,323
Research and development expense	1,113	1,558	4,302	4,716
General and administrative expense	11,679	10,522	35,342	31,891
Project development costs	6,593	4,789	19,648	10,635
Facility idling costs	550	911	2,325	2,923
Total operating expenses	25,973	25,254	82,393	73,324
Loss from operations	(24,008)	(20,726)	(71,178)	(60,498)
Other income (expense)
Interest expense	(1,107)	(540)	(2,762)	(1,615)
Interest and investment income	3,843	5,261	12,579	14,083
Other income, net	116	305	328	292
Total other income, net	2,852	5,026	10,145	12,760
Net loss	$ (21,156)	$ (15,700)	$ (61,033)	$ (47,738)
Net loss per share - basic (in dollars per share)	$ (0.09)	$ (0.07)	$ (0.25)	$ (0.20)
Net loss per share - diluted (in dollars per share)	$ (0.09)	$ (0.07)	$ (0.25)	$ (0.20)
Weighted-average number of common shares outstanding - basic (in shares)	239,445,900	239,537,811	239,767,047	238,100,986
Weighted-average number of common shares outstanding - diluted (in shares)	239,445,900	239,537,811	239,767,047	238,100,986