IL SB3627

Creates standardized property tax valuation procedures for eligible energy storage systems with capacity up to 2 megawatts, including electrochemical, thermal, and electromechanical technologies

Establishes a base valuation of $500,000 per megawatt of nameplate capacity (2021 real property cost basis), adjusted annually using the Consumer Price Index

Applies a 25-year depreciation schedule, with property value not allowed to fall below 30% of the trended cost basis

Exempts eligible energy storage systems from equalization factors applied by the Department of Revenue, boards of review, assessors, or chief county assessment officers

Applies to assessment years 2021 through 2040 and excludes energy storage systems associated with facilities eligible for renewable energy credits under the Illinois Power Agency Act