Revenue Recognition

3 Months Ended

Mar. 31, 2024

Revenue from Contract with Customer [Abstract]

Revenue Recognition

Revenue Recognition

The Company primarily earns revenue from sales of its energy storage systems and services including installation, commissioning and extended warranty services. Product revenues, which are generally recognized at a point in time, and service revenues, which are generally recognized over time, are as follows:

	For the Three Months Ended March 31,
	2024		2023
Product revenue	$	6,501	$	8,675
Service revenue	100		160
Total revenues	$	6,601	$	8,835

For the three months ended March 31, 2024, the Company had one customer that accounted for 88.1% of total revenue; for the three months ended March 31, 2023, we had one customer that accounted for 97.0% of total revenue.

Lessor revenue

The Company leases battery energy storage systems to one customer through a sales-type lease with a 20-year term. No revenue was recognized from the sales-type lease for the three months ended March 31, 2024 and 2023.

Contract assets and Contract liabilities

The following table provides information about contract assets and contract liabilities from contracts with customers. Contract assets, current, Contract liabilities, current and Contract liabilities, long-term are included separately on the Unaudited Condensed Consolidated Balance Sheets and contract assets expected to be recognized in greater than twelve months are included under Other assets, net.

	March 31, 2024		December 31, 2023
Contract assets	$	12,894	$	8,322
Contract liabilities	$	7,111	$	6,610

The Company recognizes contract assets for certain contracts in which revenue recognition performance obligations have been satisfied but invoicing to the customer has not yet occurred. Contract liabilities primarily relate to consideration received from customers in advance of the Company’s satisfying performance obligations under contractual arrangements. Contract balances are reported in a net contract asset or liability position on a contract-by-contract basis at the end of each reporting period.

Contract assets increased by $4,572 during the three months ended March 31, 2024 due to recognition of revenues for which invoicing has not yet occurred. Contract liabilities increased by $501 during the three months ended March 31, 2024, reflecting $798 of revenue recognized from customers and offset by $1,299 in customer advance payments.

Contract liabilities of $2,828 as of March 31, 2024 are expected to be recognized within the next twelve months and long-term contract liabilities of $4,283 are expected to be recognized as revenue in greater than twelve months. Contract assets of $11,075 as of March 31, 2024 are expected to be recognized within the next twelve months and long-term contract assets of $1,819 are expected to be recognized as accounts receivable in greater than twelve months.

Remaining Performance Obligations

Remaining performance obligations (“RPO”) represent the allocated transaction price of unsatisfied or partially unsatisfied performance obligations. The Company expects to recognize revenue related to the RPOs as the performance obligations are satisfied in accordance with the Company’s revenue recognition policy, which can be found in Note 2, Summary of Significant Accounting Policies, of the Company’s Annual Report on Form 10-K for the year ended December 31, 2023