Ballpark Lab
Illinois solar estimate

Solar Panel Cost in Illinois (2026)

Installed solar in Illinois runs about $2.85 per watt — roughly 10% above the national average of $2.58/W. With the federal residential tax credit (25D) gone as of 2026, payback here rests on a $0.18/kWh power price and 4.1 daily peak sun hours.

Worked example: a typical $150/month home in Illinois

A $150/month electric bill in Illinois works out to about 9,890 kWh a year. Sizing a cash-purchase system to cover 100% of that:

System size
8.4 kW
Panels
21
Annual offset
102%
Gross cost
$26,440
Federal credit (25D)
$0
Expired 12/31/2025 — $0
State incentive
$2,644
Net cost
$23,796
Payback
11.1 yr
25-year savings
$42,782

Last updated June 30, 2026

Illinois solar numbers

Installed price
$2.85 / watt
Electricity price
$0.18 / kWh
Peak sun hours
4.1 hrs/day
State incentive
10%
Net-metering value
100% of retail

$/W: industry pricing surveys · electricity: U.S. EIA, 12-month average through April 2026 · sun hours: NREL.

Local context: Illinois Shines (SRECs) and net metering combine to offset the state's moderate sun.

Estimate your own Illinois system

Adjust the bill, ownership, and battery options below — it's pre-set to Illinois's pricing and sun hours.

Tell us about your home

Average monthly electric bill$210
Estimated system cost
$30,937$40,183
11.6 kW29 panels
Low $31kMost likely ~$35,560High $40k
Federal tax credit
— expired Dec 2025, we won't pretend otherwise
$0
State & utility incentives
–$3,556
Est. annual savings
$2,528
Payback period
~10.9 yr
Net cost
$28k–$36k
25-year net savings
+$59,936
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Monthly shape modeled with NREL PVWatts® v8 (NSRDB 2020 TMY) — updated July 18, 2026.

Electricity 18.2¢/kWh — U.S. EIA, 12-month average through April 2026.

iA ballpark estimate for planning — not a final quote.

Data: U.S. EIA · OpenEI URDB · Google Solar · NREL PVWatts · DSIRE · IRS · ENERGY STAR · industry surveys see all sources

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