10. Revenue Recognition

The Company derives its revenues primarily from the sale of microturbine products, accessories, parts, equipment rentals and services.

The Company determines revenue recognition through the following steps:

Microturbine Products The Company recognizes revenue when the performance obligation identified under the terms of the contract with its customer is satisfied, which generally occurs, for microturbine products, upon the transfer of control in accordance with the contractual terms and conditions of the sale. The majority of the Company’s revenue associated with a microturbine product is recognized at a point in time when the microturbine product is shipped to the customer. On occasion, the Company enters into bill-and-hold arrangements. Each bill-and-hold arrangement is reviewed and revenue is recognized only when certain criteria have been met: (i) the reason for the bill-and-hold arrangement is substantive; (ii) the product is segregated from the Company’s other inventory items held for sale; (iii) the product is ready for shipment to the customer; and (iv) the Company does not have the ability to use the product or direct it to another customer.

Advanced payments in the form of customer deposits are received on these contracts, typically providing for a substantial portion of the contract value to be paid prior to shipment.  Advance payments are not considered a significant financing component as they are typically received less than one year before the related performance obligations are satisfied. Payment terms in contracts with customers typically are 30 or 60 days. The Company extends payment terms past 60 days only on a limited basis, and thus any financing component is not considered material.

Accessories and Parts The Company recognizes revenue when performance obligations identified under the terms of contracts with its customers are satisfied, which generally occurs, for accessories and parts, upon the transfer of control in accordance with the contractual terms and conditions of the sale. The revenue associated with accessories and parts is recognized at a point in time when the material is shipped to the customer.

Warranty Services Revenue from extended warranties is recognized when or as the obligations are satisfied. There are two types of warranties: standard (assurance) and extended warranties. Standard warranties do not represent separate performance obligations but are reflected as a liability associated with the purchase of the product. Extended warranties are separate offerings typically for 12-, 24- or 36-month periods beyond the standard warranty that are separate performance obligations recognized as an over-time performance obligation based on the extended warranty period. The Company records amounts billed to customers for reimbursement of shipping and handling costs within revenue. Shipping and handling costs associated with outbound freight after control over a system has transferred to a customer are accounted for as fulfillment costs and are included in cost of goods sold. Sales taxes and other usage-based taxes are excluded from revenue.

Factory Protection Plan (“FPP”), Long Term Maintenance Agreements and Service Cost Reimbursement In addition to the provision of standard warranties, the Company is replacing the FPP with Long Term Maintenance Agreements (“LTMA”), Similar to the FPP, the LTMA are intended to minimize product downtime and control maintenance costs to ensure the microturbine system will operate when needed and perform as intended at the lowest cost of ownership. Revenue related to the Company’s performance obligation to provide replacement parts as needed is recognized over the term of the LTMA contract, intervals aligned to the monthly service period for that customer. LTMA contracts typically range from four years to twelve years and may be cancelled at any time. The related costs for LTMA contracts become the Company’s obligation and are accrued at the time a customer submits a claim, and the claim’s compliance with the terms of the plan are confirmed. The accrual reflects the Company’s best estimate of the probable liability under the replacement part obligation based on actual experience. The LTMA contract offers flexible options for customers, as it can either begin while the system is still covered under the standard warranty or commence once the standard warranty period has expired. The LTMA includes an annual escalator, covers critical components only such as the engine, fuel and electronic components, and excludes freight cost. LTMA contracts do not include labor reimbursement.

Comprehensive FPP and LTMA service contracts require payment at the beginning of the contract period. Advance payments are not considered a significant financing component as they are typically received less than one year before the related performance obligations are satisfied. These payments are a contract liability and are classified as deferred revenue in the Condensed Consolidated Balance Sheets. The performance obligation is fulfilled as the control passes to the customer through the passage of time and recognition of deferred revenue from the FPP or LTMA contracts is recognized in the Condensed Consolidated Statement of Operations. The deferred revenue relating to the annual maintenance service contracts is recognized in the Condensed Consolidated Statement of Operations on a straight-line basis over the expected term of the contract.

The remaining FPP contracts may include labor reimbursement on the labor performed on a microturbine system. Due to the nature of the arrangement, labor reimbursements are accounted for under Accounting Standard Codification (“ASC”) 460 and are recognized as contra revenue as consideration paid to a customer under ASC 606. An Authorized Service Provider (“ASP”) must perform the labor. ASPs submit claims for labor reimbursements and are credited for the cost of labor if the repairs meet the Company’s prescribed standards. The Company is unable to develop a reasonable estimate of the maximum potential payout under these arrangements because the FPP contracts do not contain a limit on the number of labor reimbursements that may be submitted. However, given historical practice, the Company has priced the FPP to cover all costs incurred related to the labor reimbursement and is not exposed to significant losses over the FPP premium.

The labor reimbursement is separate and distinct from the parts offering; therefore, the Company allocates a portion of the transaction price to the labor reimbursement based on a relative standalone selling price (“SSP”). The Company applies judgment in determining the SSP as the labor reimbursement is not sold separately. The Company will recognize a liability at the inception of the executed FPP agreement for the premium received in advance for the Labor offering. Income will be recognized on a net, straight-line basis with labor reimbursement costs recognized when incurred.

Rentals The Company accounts for leases to customers in accordance with lessor accounting under ASC 842. The Company utilizes a portfolio approach by grouping together many similar assets being leased to a single customer. Leases are classified as either sales-type leases or operating leases. The Company’s leases are classified as a sale-type lease if one of the five criteria per the guidance are met. Other leases are classified as operating leases.

For sales-type leases, upon lease commencement, the Company records and presents as a separate line item in the Condensed Consolidated Balance Sheets, the present value of the lease payments as a lease receivable, along with the residual asset discounted using the rate implicit in the lease. Revenue is recognized on the Condensed Consolidated Statements of Operations in the amount of the lease receivable as part of Product and Accessories revenue and the cost of sales in the amount of the carrying value of the underlying asset less the unguaranteed residual asset. The Company believes this is generally more aligned to its current presentation of product sales. After the commencement date, the Company recognizes the imputed interest income as part of the net sales using the effective interest method.

For operating leases, the Company recognizes the underlying assets as rental lease assets. The asset is depreciated on a straight-line basis to its estimated residual value over the estimated useful life. The lease payments are recognized over the lease term on a straight-line basis as part of Rental Revenue.

Contracts with Multiple Performance Obligations

The Company enters into contracts with its customers that often include promises to transfer multiple products, parts, accessories and services. A performance obligation is a promise in a contract with a customer to transfer products or services that are distinct. Determining whether products and services are distinct performance obligations that should be accounted for separately or combined as one unit of accounting may require significant judgment.

Products, parts and accessories are distinct as such services are often sold separately. In determining whether FPP and LTMA service contracts are distinct, the Company considers the following factors for each services agreement: availability of the services from other vendors, the nature of the services, the timing of when the services contract was signed in comparison to the product delivery date and the contractual dependence of the product on the customer’s satisfaction with the professional services work. To date, the Company has concluded that all of the service contracts included in contracts with multiple performance obligations are distinct.

The Company allocates the transaction price to each performance obligation on a SSP basis. The SSP is the price at which the Company would sell a promised product or service separately to a customer. Judgment is required to determine the SSP for each distinct performance obligation.

The Company determines SSP by considering its overall pricing objectives and market conditions. Significant pricing practices taken into consideration include the Company’s discounting practices, the size and volume of the Company’s transactions, the customer demographic, the geographic area where systems and services are sold, price lists, its go-to-market strategy, historical sales and contract prices. The determination of SSP is made through consultation with and approval by the Company’s management, taking into consideration the go-to-market strategy. As the Company’s go-to-market strategies evolve, the Company may modify its pricing practices in the future, which could result in changes to SSP.

In certain cases, the Company may be able to establish SSP based on observable prices of products or services sold separately in comparable circumstances to similar customers. The Company uses a single amount to estimate SSP when it has observable prices.

If SSP is not directly observable, for example when pricing is highly variable, the Company may use a range of SSP. The Company determines the SSP range using information that may include market conditions or other observable inputs. The Company typically has more than one SSP for individual products and services due to the stratification of those products and services by customer size and geography.

The following table presents disaggregated revenue by business group (in thousands):

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The following table presents disaggregated revenue by geography based on the primary operating location of the Company’s customers (in thousands):

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Contract Balances

The Company’s deferred revenues consist of deposits and advance payments for microturbine products, parts, accessories and parts ordered under sales contracts, which have not yet been delivered (contract liabilities), as well as advance payments on service obligations, FPP contracts and extended warranties. Deposits are primarily non-refundable cash payments from distributors for future orders. The current portion of deferred revenue and the non-current portion of deferred revenue are included in the Current Liabilities and Long-Term Liabilities, respectively, in the Condensed Consolidated Balance Sheets.

Changes in deferred revenue consisted of the following (in thousands):

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Deferred revenue attributed to FPP and LTMA contracts represents the unearned portion of the Company’s contracts. FPP contracts are generally paid quarterly in advance, with revenue recognized on a straight-line basis over the contract period. As of December 31, 2025, approximately $4.9 million of revenue is expected to be recognized from the remaining contract liability for FPP contracts. The Company expects to recognize revenue on approximately $4.2 million of these unfulfilled performance obligations over the next 12 months and the balance of $0.7 million will be recognized thereafter.

Unsatisfied Performance Obligations

The Company has elected the practical expedient to disclose only the value of unsatisfied performance obligations for contracts with an original expected length greater than one year. The majority of the Company’s product sales have relatively short periods of manufacture and result in fulfillment (lead times) of less than one year after manufacture and delivery and thus are excluded from this disclosure.

Our service contracts have periods of greater than one year in duration, however they are cancellable without any significant penalty, therefore the enforceable duration of these contracts is considered to be one year or less and thus under the practical expedients they are also excluded from this disclosure.

Practical Expedients

The Company applies the practical expedient for contracts of one year or less in duration for the direct and incremental costs to obtain a contract to expense such costs as incurred. Contracts are considered to be the individual sales orders received from the distributors and as per above, such orders are typically fulfilled in less than one year. These costs are recorded within sales and marketing expenses in the accompanying Condensed Consolidated Statements of Operations.

Warranty The Company provides for the estimated costs of warranties at the time revenue is recognized under ASC 450. The specific terms and conditions of those warranties vary depending upon the microturbine product sold and the geography of sale. The Company’s product warranties generally start from the delivery date and continue for up to twenty-four months. Factors that affect the Company’s warranty obligation include product failure rates, anticipated hours of product operations and costs of repair or replacement in correcting product failures. These factors are estimates that may change based on new information that becomes available each period. Similarly, the Company also accrues the estimated costs to address reliability repairs on products no longer in warranty when, in the Company’s judgment, and in accordance with a specific plan developed by the Company, it is prudent to provide such repairs. The Company assesses the adequacy of recorded warranty liabilities quarterly and adjusts the liability as necessary. When the Company has sufficient evidence that product changes are altering the historical failure occurrence rates, the impact of such changes is then taken into account in estimating future warranty liabilities.

Research and Development (“R&D”) The Company accounts for grant distributions and development funding as offsets to R&D expenses and both are recorded as the related costs are incurred in the Company’s statement of operations. There were no offsets to R&D during Fiscal 2026 and 2025.