IL SB4020

Creates the District Energy and Thermal Energy Storage Parity Act establishing an optional certification process through the Illinois Commerce Commission for qualified district energy infrastructure projects, enabling expedited permitting and standardized environmental review

Requires developers to obtain a District Energy Feasibility Assessment for new buildings of 100,000+ square feet, multi-building campuses of 500,000+ square feet, or major renovations exceeding 100,000 square feet or 50 dwelling units

Directs the Environmental Protection Agency to establish a grant program supporting energy transfer stations, heat recovery equipment, dispatchable thermal energy storage, and electrification equipment, with priority for projects demonstrating peak demand reduction and CO2 emissions mitigation

Requires the Commission within 180 days to develop standardized thermal service agreement templates with rate stabilization options including indexed pricing and collar mechanisms, while exempting district energy companies operating before January 1, 2026 from Commission regulation

Amends multiple tax codes to provide exemptions for district energy equipment, directs the Department of Commerce and Economic Opportunity to create a municipal alignment toolkit, and authorizes the Illinois Finance Authority to provide loans and financial assistance for qualified district energy infrastructure