Illinois solar calculator

Live production from NLR (formerly NREL) PVWatts V8. Illinois switched NEW residential solar installs to SUPPLY-ONLY net metering on January 1, 2025 — exports are credited only against supply + transmission, not delivery. Self-consumption still offsets the full retail rate. The export figure here is a conservative estimate (~50% of retail); your actual ComEd or Ameren split may differ. Illinois has NO state income tax credit (some quotes claim $10,000 — that's wrong) and NO residential sales tax exemption. Property tax is 100% exempt. Illinois Shines (SREC program) is a major incentive but its payment structure varies — not modeled here. Defaults: south-facing roof mount, 20° tilt, 14% losses.