Solar Calculators for Chicago, Illinois

Free tools with illustrative Chicago planning inputs. Replace energy rates and installation costs with your bill and written quote.

Quick answer

Start with your exact utility account and roof design. The 4 sun hours and 15.0 cents/kWh below are planning assumptions, not verified current rates for Chicago. Confirm ComEd eligibility and export settlement.

Notes updated 2026-07-26

Best for: Chicago homeowners comparing a proposal or estimating savings before calling installers.
Inputs needed: 12-month kWh usage, roof shade, ComEd, quoted $/W
Formula used: Local production = system kW × local peak sun hours × 365, then adjusted for losses.
Method references: NREL PVWatts, ComEd, Illinois incentive rules

Peak sun hours

hrs/day planning assumption

Illustrative energy rate

15.0¢

per kWh (ComEd)

Typical install cost

$3/W

planning assumption, not a market median

Net metering policy: Full retail net metering ✓

What Chicago homeowners should check

Chicago solar designs should account for snow, freeze-thaw cycles, strong winds, and shading from neighboring buildings or mature trees. Flat roofs also require careful attention to drainage, ballast, and membrane warranties.

ComEd serves most city addresses. Verify the current net-metering treatment, interconnection queue, and Illinois incentive paperwork because missing documentation can delay or reduce expected benefits.

At the state level, Illinois currently uses full retail net metering. A typical interconnection takes 4–10 weeks, but utility review and local permitting can extend that range. Check current rules before relying on a proposal's export-credit or installation-date assumptions.

What should I verify before signing a solar contract in Chicago?

Confirm that the quote names your actual utility, uses a recent electricity rate, includes measured shade and roof-condition findings, and explains who handles permits and interconnection. Ask the installer to separate guaranteed equipment and workmanship terms from estimated production, incentives, and savings.

Illustrative 8 kW system in Chicago

Annual production

10,035 kWh

Retail-value ceiling

$1,505

System cost (est.)

$24,000

Energy-only cost/value ratio

~16 yrs

Illustrative 4 peak sun hours, 14.08% production losses, 15.0 cents/kWh and $3/W. The retail-value ceiling assumes every kWh earns retail value; lower export credits reduce it. The cost/value ratio is not a full payback model and excludes repairs, financing and rate changes. No new Section 25D homeowner credit in 2026.