17. Revenue

Disaggregation of revenue

The following table provides information about disaggregation of revenue (in thousands):

Year ended December 31,

Major products/services lines

2025

  ​ ​ ​

2024

  ​ ​ ​

2023

Sales of fuel cell systems

$

54,012

$

52,110

$

181,168

Sales of hydrogen infrastructure

26,750

69,122

183,606

Sales of electrolyzers

187,780

135,504

82,611

Sales of engineered equipment

6,854

22,092

32,361

Services performed on fuel cell systems and related infrastructure

94,462

52,169

39,093

Power purchase agreements

107,572

77,842

63,731

Fuel delivered to customers and related equipment

133,411

97,882

66,246

Sales of cryogenic equipment and liquefiers

95,685

111,507

231,687

Other

3,393

10,586

10,837

Net revenue

$

709,919

$

628,814

$

891,340

Contract balances

Contract assets relate to contracts for which revenue is recognized on a straight-line basis, however billings escalate over the life of a contract. Contract assets also include amounts recognized as revenue in advance of billings to customers, which are dependent upon the satisfaction of another performance obligation. These amounts are included in contract assets on the consolidated balance sheets.

The deferred revenue and contract liabilities relate to the advance consideration received from customers for services that will be recognized over time (primarily fuel cell and related infrastructure services and electrolyzer systems and solutions). Deferred revenue and contract liabilities also include advance consideration received from customers prior to delivery of products. These amounts are included within deferred revenue and other contract liabilities on the consolidated balance sheets.

Significant changes in the contract assets and the deferred revenue and contract liabilities balances during the period are as follows (in thousands):

Contract assets

Year ended December 31,

2025

  ​ ​ ​

2024

Transferred to receivables from contract assets recognized at the beginning of the period

$

(21,348)

$

(27,513)

Change in contract assets related to warrants

(3,729)

(4,909)

Foreign currency translation gain

1,208

Impairment

(28,105)

(35,118)

Revenue recognized and not billed as of the end of the period

63,364

29,566

Net change in contract assets

$

11,390

$

(37,974)

Deferred revenue and other contract liabilities

Year ended December 31,

2025

  ​ ​ ​

2024

Increases due to customer billings, net of amounts recognized as revenue during the period

$

19,144

$

74,702

Change in contract liabilities related to warrants

260

440

Foreign currency translation loss

6,814

Revenue recognized that was included in the contract liability balance as of the beginning of the period

(127,898)

(160,819)

Net change in deferred revenue and other contract liabilities

$

(101,680)

$

(85,677)

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

December 31, 2025

  ​ ​ ​

period (years)

Sales of fuel cell systems

$

55,245

1 - 2

Sales of hydrogen installations and other infrastructure

42,695

1 - 2

Sales of electrolyzers

103,122

1 - 3

Sales of engineered equipment

997

1

Services performed on fuel cell systems and related infrastructure

138,586

1 - 10

Power purchase agreements

278,721

1 - 10

Fuel delivered to customers and related equipment

63,831

1 - 10

Sales of cryogenic equipment and other

40,237

1

Other

693

1

Total estimated future revenue

$

724,127

Historical Timeline

Fiscal YearFiled
2025Mar 2, 2026Showing above
2024Mar 3, 2025
2023Feb 29, 2024
2022Mar 1, 2023
2021Mar 1, 2022
2020May 14, 2021
2019Mar 10, 2020
2018Mar 13, 2019
2017Mar 12, 2018
2016Mar 10, 2017
2015Mar 15, 2016

About Revenue Disclosures

Revenue disclosures under ASC 606 explain how a company identifies performance obligations, allocates transaction prices, and determines when revenue is recognized. This section is essential for understanding whether reported revenue reflects genuine economic activity or aggressive accounting choices. Analysts examine the mix of point-in-time versus over-time recognition, which directly affects revenue timing and comparability.

Key signals: rising contract liabilities (deferred revenue) suggest strong future revenue visibility, while declining contract assets may indicate slowing project milestones. Watch for variable consideration estimates — rebates, returns, and performance bonuses that require management judgment. Significant changes in disaggregated revenue by geography or product line can reveal shifting business mix before it appears in headline numbers. Compare revenue growth against contract liability growth to assess sustainability, and scrutinize any changes in the timing of recognition that coincide with earnings pressure.