21. Supplemental Balance Sheet Information

Prepaid and Other Assets

The following table presents the components of prepaid expenses, other current assets, and other long-term assets as of March 31, 2026 and 2025 (in thousands):

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Prepaid Royalties

The Company holds a prepaid royalty asset that is being amortized over a fifteen-year period through September 2033 using an effective royalty rate methodology. The fifteen-year amortization period reflects the minimum expected life cycle of the current generation of microturbine products. The effective royalty rate is calculated as the total prepaid royalty settlement divided by total projected microturbine system unit shipments over the amortization period.

On a quarterly basis, the Company re-forecasts projected microturbine unit shipments to determine whether an adjustment to the effective royalty rate is necessary and whether any impairment indicators exist. No impairment was identified as of March 31, 2026 or March 31, 2025.

As of March 31, 2026, the remaining balance of the prepaid royalty asset was $2.0 million, of which $0.1 million is classified as current and $1.9 million is classified as non-current on the Consolidated Balance Sheets.