v3.26.1
REVENUE RECOGNITION
 6 Months Ended
Jun. 30, 2026
Revenue from Contract with Customer [Abstract]  
REVENUE RECOGNITION REVENUE RECOGNITION
The Company recognized revenue for the product and service categories as follows for the three and six months ended June 30, 2026 and 2025 (amounts in thousands):
Three Months Ended June 30,Six Months Ended June 30,
2026202520262025
Sale of energy storage products$14,696 $7,711 $34,406 $12,602 
Tolling and power purchase agreement (“PPA”) revenue (1)
2,026 390 3,554 390 
Operation and maintenance services445 277 889 553 
Software licensing187 120 369 232 
Intellectual property (“IP”) licensing15 14 30 3,269 
Total revenue$17,369 $8,512 $39,248 $17,046 
__________________
(1) Revenue from the arrangement accounted for as an operating lease was $1.1 million and $1.6 million for the three and six months ended June 30, 2026, respectively, and was $0.4 million for each of the three and six months ended June 30, 2025.
Remaining Performance Obligations
Remaining performance obligations represent the amount of unearned transaction price for contracts accounted for under ASC 606, Revenue from Contracts with Customers (“ASC 606”). As of June 30, 2026, the amount of the Company’s remaining performance obligations was $362.0 million, of which approximately 77% related to domestic projects and approximately 23% related to international projects. The Company expects to recognize approximately 87% of the remaining performance obligations as revenue over the next 12 months and the remainder more than 12 months from June 30, 2026.
Contract Balances
The following table provides information about contract assets and contract liabilities from contracts with customers accounted for under ASC 606 (amounts in thousands):
June 30,
2026		December 31,
2025
Refundable contribution$25,000 $25,000 
Unbilled receivables15,228 20,732 
Less allowance for credit losses(25,163)(25,101)
Contract assets, net of allowance for credit losses$15,065 $20,631 
Contract liabilities$29,726 $6,610 
Contract assets consist of a refundable contribution and unbilled receivables. The refundable contribution was initially payable to the Company upon the customer’s first gravity energy storage system achieving substantial completion, subject to potential downward adjustment for liquidated damages if specified performance metrics were not met. In 2024, the
customer agreed to remove the substantial completion condition and committed to repay the refundable contribution in the second half of 2024. However, the customer did not remit payment, and during 2024 the Company increased its allowance for credit losses to fully reserve this receivable.
Unbilled receivables represent the estimated value of unbilled work for projects with performance obligations recognized over time.
Contract liabilities consist of deferred revenue. Under certain contracts, the Company may be entitled to invoice the customer and receive payments in advance of performing the related contract work. In those instances, the Company recognizes a liability for advance billings in excess of revenue recognized, which is referred to as deferred revenue. Deferred revenue is not considered to be a significant financing component because it is generally used to meet working capital demands that can be higher in the early stages of a contract. For the three and six months ended June 30, 2026, the Company recognized revenue of $3.3 million and $4.0 million, respectively, related to amounts that were included in the deferred revenue balance as of the beginning of each period. For the three and six months ended June 30, 2025, the Company recognized revenue of $0.1 million and $8.4 million, respectively, related to amounts that were included in the deferred revenue balance as of the beginning of each period.
Lease Revenue
The Company has one tolling agreement that is accounted for as a lease under ASC 842, Leases (“ASC 842”). The agreement is accounted for as a lease because the customer (the “lessee”) has the right to obtain substantially all of the economic benefits from the use of the energy storage system and has the right to direct its use throughout the agreement's term. The Company, as lessor, is entitled to receive monthly lease payments based on a contractual floor amount (the “Monthly Floor”), which is subject to reduction each month based on the availability and round-trip efficiency of the energy storage system (the “Effective Monthly Floor”). Lease income is recognized monthly based on a straight-line allocation of the Monthly Floor over the term of the contract, to the extent it represents fixed or in-substance fixed consideration. Any difference between the recognized lease income and the Effective Monthly Floor earned in a given period is recorded as an adjustment to lease income in that period.
At the end of each contract year, if cumulative lease payments received during the year are less than the sum of the twelve Effective Monthly Floors, the lessee is required to make a true-up payment for the shortfall. The Company is also entitled to variable lease payments equal to a specified percentage of the net market revenue generated by the lessee that exceeds the cumulative Effective Monthly Floors for that contract year.
The lease does not contain an option for the lessee to extend the term or purchase the asset. The agreement may be terminated early by either party under certain conditions, including for prolonged force majeure events, or by the non-defaulting party upon an event of default.
The aggregate remaining Monthly Floor payments as of June 30, 2026 presented in the table below do not reflect potential reductions due to performance-based adjustments that may occur throughout the contract term (amounts in thousands) (1):
20262027202820292030ThereafterTotal
$2,394 $4,788 $4,788 $4,788 $4,446 $18,468 $39,672 
__________________
(1) The table reflects contractual Monthly Floor payments due under the lease agreement for each fiscal year. These amounts represent the stated floor amounts prior to any performance-based adjustments. Actual lease payments may be lower in any given period based on the lessee’s achievement of availability and round-trip efficiency thresholds. Additionally, the timing of cash receipts within a year may vary, as monthly payments are dependent on the lessee's net market revenue. Pursuant to the agreement, if cumulative lease payments for the contract year are less than the aggregate Effective Monthly Floors earned, the lessee is required to pay the shortfall to the Company in an annual true-up following the end of each contract year in May.