If the installation was completed in 2022, you are eligible to claim the tax credit on your 2022 tax return. DoninGA cited above from the IRS that the credit can be claimed when the system is installed.
This is from the IRS FAQs:
Q1. May a taxpayer claim the credits in the year of purchase if installation of the qualifying property occurs in a later year? (added December 22, 2022)
A1. No. A taxpayer may not claim the credits until the year the property is installed.
If the unlikely event occurs that the county says no to the solar energy system, you can amend the 2022 tax return.
@mr petey
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