Illinois solar policy planning
Solar savings depend on two values: electricity you avoid buying from the grid and exported solar energy your utility credits back. This page explains how SolarCalcNow models export value as a planning assumption, not a final utility-specific tariff.
Source coverage: ComEd
For new residential interconnections from January 1, 2025, ComEd credits offset supply charges, not the entire delivered retail bill. Verify supplier terms and interconnection date. REC payments are separate.
Read the primary source — ComEd Net Metering — 2025 onwardSource checked: · Next review due: 2026-10-04
10%, 35% and 100% of retail are author-selected sensitivity scenarios, not this utility's tariff. Same inputs: 900 kWh/month, 100% annual energy target, 55% direct solar use, low shade, 400 W panels. Change only export value to see its effect on energy savings and gross-cost payback.
| Export / retail | Annual energy savings | Simple gross-cost payback |
|---|---|---|
| 10% | $1,278 | 18.7 years–28.1 years |
| 35% | $1,520 | 15.7 years–23.7 years |
| 100% | $2,148 | 11.1 years–16.7 years |
Annual totals cannot reproduce hourly export prices, monthly credit expiry, demand charges or utility-specific minimum bills. Match the utility and interconnection date before selecting a scenario. For an actual proposal, request a bill simulation under that tariff.
After checking export value, compare the same assumptions against installer proposals and incentive claims.