35 ILCS 200/10-925: Improvement valuation of commercial energy systems.

Beginning in assessment year 2026, the fair cash value of commercial energy storage system improvements shall be determined by subtracting the allowance for physical depreciation from the commercial energy storage system trended real property cost basis. Functional obsolescence and external obsolescence of the commercial energy storage system improvements may further reduce the fair cash value of the improvements to the extent the obsolescence is proven by the taxpayer by clear and convincing evidence, except that the combined depreciation from all functional and economic obsolescence shall not exceed 70% of the trended real property cost basis. The chief county assessment officer may make reasonable adjustments to the actual age of the commercial energy storage system to account for the routine replacement or upgrade of system components.