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Energy Systems, net
 12 Months Ended
Dec. 31, 2025
Energy Systems Disclosure [Abstract]  
Energy Systems, net Energy Systems, net
Energy systems, net consists of the following (in thousands):
December 31,
20252024
Energy system equipment costs$16,090,654 $14,258,772 
Inverters and batteries3,343,643 2,554,739 
Total energy systems19,434,297 16,813,511 
Less: accumulated depreciation and amortization(3,384,021)(2,732,888)
Add: construction-in-progress767,587 951,492 
Total energy systems, net$16,817,863 $15,032,115 
All energy systems, including construction-in-progress, have been leased to or are subject to signed Customer Agreements with customers. In accordance with its policy, the Company periodically reviews the
estimated useful lives of its fixed assets on an ongoing basis and recognizes any changes in estimated useful lives by prospectively adjusting depreciation expense. During the three months ended June 30, 2024, the Company completed an assessment of its battery equipment, which included review of an independent engineering report, and determined that the useful life of its batteries was longer than the estimated useful life being used to calculate depreciation. As a result, effective April 1, 2024, the Company changed its estimated useful life to reflect the estimated period these assets will remain in service. The estimated useful life of batteries previously was 10 years and was increased to 15 years. The impact of this change in estimate reduces depreciation expense and was immaterial for the twelve months ended December 31, 2024. For batteries placed in service as of the effective date of April 1, 2024, the impact on depreciation for the year ended December 31, 2024 was approximately $14.0 million. The Company recorded depreciation expense related to energy systems of $677.7 million, $584.6 million and $500.6 million for the years ended December 31, 2025, 2024 and 2023, respectively. The depreciation expense was reduced by the amortization of deferred grants of $9.5 million, $7.8 million and $8.2 million for the years ended December 31, 2025, 2024 and 2023, respectively.