| Revenue |
11. Revenue Disaggregation of revenue The following table provides information about disaggregation of revenue (in thousands): | | | | | | | Three months ended March 31, | Major products and service lines | 2026 | | 2025 | Sales of fuel cell systems | $ | 11,789 | | $ | 16,656 | Sales of hydrogen infrastructure | | 12,610 | | | 5,648 | Sales of electrolyzers | | 40,882 | | | 9,210 | Sales of engineered equipment | | 1,219 | | | 1,529 | Services performed on fuel cell systems and related infrastructure | | 21,970 | | | 16,874 | Power purchase agreements | | 26,290 | | | 23,210 | Fuel delivered to customers and related equipment | | 35,795 | | | 29,457 | Sales of cryogenic equipment and liquefiers | | 12,522 | | | 30,463 | Other | | 436 | | | 627 | Net revenue | $ | 163,513 | | $ | 133,674 |
Contract balances Significant changes in the contract assets and the deferred revenue and other contract liabilities balances during the period are as follows (in thousands): | | | | | | Contract assets | Three months ended | | Year ended | | March 31, 2026 | | December 31, 2025 | Transferred to receivables from contract assets recognized at the beginning of the period | $ | (41,476) | | $ | (21,348) | Change in contract assets related to warrants | | 1,122 | | | (3,729) | Foreign currency translation (loss)/gain | | (440) | | | 1,208 | Impairment | | — | | | (28,105) | Revenue recognized and not billed as of the end of the period | | 40,800 | | | 63,364 | Net change in contract assets | $ | 6 | | $ | 11,390 |
| | | | | | Deferred revenue and other contract liabilities | Three months ended | | Year ended | | March 31, 2026 | | December 31, 2025 | Increases due to customer billings, net of amounts recognized as revenue during the period | $ | 23,322 | | $ | 19,144 | Change in contract liabilities related to warrants | | 9 | | | 260 | Foreign currency translation (gain)/loss | | (475) | | | 6,814 | Revenue recognized that was included in the contract liability balance as of the beginning of the period | | (25,678) | | | (127,898) | Net change in deferred revenue and other contract liabilities | $ | (2,822) | | $ | (101,680) |
Estimated future revenue The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) at the end of the reporting period, including provision for common stock warrants (in thousands): | | | | | | | As of | | Expected recognition | | March 31, 2026 | | period (years) | Sales of fuel cell systems | $ | 73,413 | | | 1 - 2 | Sales of hydrogen installations and other infrastructure | | 53,269 | | | 1 - 2 | Sales of electrolyzers | | 95,312 | | | 1 - 3 | Sales of engineered equipment | | 744 | | | 1 | Services performed on fuel cell systems and related infrastructure | | 146,917 | | | 1 - 10 | Power purchase agreements | | 250,267 | | | 1 - 10 | Fuel delivered to customers and related equipment | | 60,596 | | | 1 - 10 | Sales of cryogenic equipment and other | | 56,534 | | | 1 | Other | | 646 | | | 1 | Total estimated future revenue | $ | 737,698 | | | |
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