Is Solar Worth It in Illinois in 2026?
Illinois is not Arizona. At 41.3°N, a Chicago-area roof produces about 1,162 kWh per installed kilowatt per year — well below the 1,500-plus you'd get in Florida or Arizona. That's the honest starting point. What makes Illinois interesting anyway: electricity here has gotten expensive fast, and the state pays a separate cash incentive, an SREC, that most Sun Belt states don't offer.
2026 changed the federal side of the math. The 30 percent federal tax credit that used to knock thousands off an install ended for systems completed after December 31, 2025. On top of that, Illinois net metering split in two on January 1, 2025 — one deal for homeowners who got in before the deadline, a noticeably worse one for everyone after. Solar can still pencil out here, especially with SREC payments layered on top of a smaller net-metering credit, but any 2026 pitch needs to reflect all of that, not the 2023 version. This page gives you Illinois's numbers.
Illinois Electricity Prices Keep Climbing
Solar is a bet on future electricity prices: every kilowatt-hour your roof makes is one you don't buy from ComEd, Ameren, or MidAmerican. Here's the long-run trend from federal EIA data.
Full Illinois electricity price data (1990–2025)
| Year | Illinois (¢/kWh) | US avg (¢/kWh) |
|---|---|---|
| 1990 | 9.9 | 7.8 |
| 1991 | 9.9 | 8.0 |
| 1992 | 10.3 | 8.2 |
| 1993 | 10.3 | 8.3 |
| 1994 | 10.0 | 8.4 |
| 1995 | 10.4 | 8.4 |
| 1996 | 10.3 | 8.4 |
| 1997 | 10.4 | 8.4 |
| 1998 | 9.9 | 8.3 |
| 1999 | 8.8 | 8.2 |
| 2000 | 8.8 | 8.2 |
| 2001 | 8.7 | 8.6 |
| 2002 | 8.4 | 8.4 |
| 2003 | 8.4 | 8.7 |
| 2004 | 8.4 | 9.0 |
| 2005 | 8.3 | 9.5 |
| 2006 | 8.4 | 10.4 |
| 2007 | 10.1 | 10.7 |
| 2008 | 11.1 | 11.3 |
| 2009 | 11.3 | 11.5 |
| 2010 | 11.5 | 11.5 |
| 2011 | 11.8 | 11.7 |
| 2012 | 11.4 | 11.9 |
| 2013 | 10.6 | 12.1 |
| 2014 | 11.9 | 12.5 |
| 2015 | 12.5 | 12.7 |
| 2016 | 12.5 | 12.6 |
| 2017 | 13.0 | 12.9 |
| 2018 | 12.8 | 12.9 |
| 2019 | 13.0 | 13.0 |
| 2020 | 13.0 | 13.2 |
| 2021 | 13.2 | 13.7 |
| 2022 | 15.7 | 15.0 |
| 2023 | 15.7 | 16.0 |
| 2024 | 15.9 | 16.5 |
| 2025 * | 17.7 | 17.3 |
Source: US EIA, average residential retail electricity price. Values in cents per kWh. * 2025 is preliminary.
Illinois residential electricity averaged about 17.7¢ per kWh in 2025 (EIA preliminary) — roughly 112 percent higher than 2005, climbing about 3.5 percent a year over the last decade. That's a steeper 20-year climb than most Sun Belt states, even though Illinois gets less sun than they do — which is exactly what makes a slower-producing system still worth running the numbers on.
The Illinois Sun, Month by Month
Panels respond to how high the sun climbs and how long it stays up, not to air temperature — good news for Illinois, since cold, sunny winter days still produce well. But at 41.3°N, winter days are short and the sun sits low, so December and January output drops hard compared to June.
Illinois monthly solar production data
| Month | kWh per installed kW |
|---|---|
| Jan | 61 |
| Feb | 70 |
| Mar | 102 |
| Apr | 117 |
| May | 124 |
| Jun | 126 |
| Jul | 133 |
| Aug | 124 |
| Sep | 106 |
| Oct | 85 |
| Nov | 68 |
| Dec | 47 |
| Year | 1162 |
Source: NREL PVWatts typical-year estimate (Chicago), per installed kW at latitude tilt.
Illinois production is heavily loaded toward April through September, with a steep winter trough. That swing matters more here than farther south, because it's exactly what net metering is supposed to smooth out — banking summer surplus against winter draw. Whether that still works well for you depends on which net-metering rules apply to your system, covered below.
What Solar Costs in Illinois in 2026
Illinois installs run close to the national average: about $3.01 per watt pre-incentive as of June 2026, per EnergySage's Illinois local data. The average Illinois system is about 12.8 kW — larger than the typical Sun Belt system, since shorter daylight hours mean each installed kW produces less. With the federal credit gone, the number an installer quotes you is very close to what you'll actually pay before any SREC or rebate.
| System Size | Typical 2026 Cost | Roughly Offsets | Fits |
|---|---|---|---|
| 5 kW | $15,050 to $17,500 | ~5,810 kWh/yr (~$86/mo at 17.7¢) | Smaller home, lower usage |
| 8 kW | $24,000 to $28,000 | ~9,296 kWh/yr (~$137/mo) | Average-to-smaller Illinois home |
| 12 kW | $32,800 to $44,300 | ~13,944 kWh/yr (~$206/mo) | Average Illinois system size |
There's no blanket sales-tax exemption for a purchased Illinois system, so standard sales tax applies to the equipment (leases are different — see below). Get at least three quotes and compare price per watt.
Estimate Your Illinois Payback
The calculator below is set to Illinois's average electricity rate and Chicago-area production. Enter your own monthly bill to see an estimated system size, payback period, and 25-year savings. Illinois rates have risen about 3.5 percent a year over the last decade — a reasonable default for the inflation field, though you can drag it to test other scenarios.
Illinois Solar Incentives That Still Exist in 2026
Here's what's gone, and what's still real.
- Gone — the 30 percent federal credit: The federal Residential Clean Energy Credit (25D) ended for installations completed after December 31, 2025, with no phase-out. If a pitch still assumes it, the rest of the pitch is probably out of date too.
- Still here — Illinois Shines SRECs: The Adjustable Block Program pays homeowner-owned systems up to 25 kW an upfront REC contract based on 15 years of expected production (1 SREC = 1 MWh). Pricing is in "Block 6" as of early 2026, around $78 per REC depending on utility territory, with a proposed Program Year 2026-27 update (ICC order expected around February 17, 2026) that could raise values 34 to 43 percent, plus a new $5/REC equity adder for Equity Eligible projects. This stacks on top of your net-metering credit — a separate check, not an either/or.
- Payment structure is changing: SREC payouts have historically arrived as one lump sum. Starting June 1, 2026, systems under 25 kW AC move to a 7-year schedule instead — 50 percent in year one, the rest spread quarterly across years 2-7. Confirm the mechanics with an Illinois Shines Approved Vendor or at illinoisshines.com before counting on the old timeline.
- Still here — Distributed Generation rebate: A one-time $300-per-kW-DC rebate for systems using a grid-interactive smart inverter, available in both ComEd and Ameren territory — created to soften the 2025 net-metering cut below.
- Still here — property tax treatment: Under 35 ILCS 200/10-10, a qualifying system is assessed at the lower of its value with a conventional system versus its actual value with solar, which prevents panels from raising your tax bill. Not automatic — you file a claim with your county's Chief County Assessment Officer.
- No state income tax credit: Illinois never had a state-level credit equivalent to the old federal 25D — SRECs and the DG rebate are the state-side incentives instead.
- Leases only — sales tax exemption: Since January 1, 2025 (SB1633), leased systems are exempt from Illinois sales and use tax. That doesn't apply if you buy, and leasing forfeits SRECs and the property-tax treatment to the lease company, routing any federal credit to them under 48E instead of you.
Net Metering: The 2025 Cutover
This is the single most Illinois-specific thing in this guide. Under the Climate and Equitable Jobs Act (CEJA), Illinois net metering split into two tracks on January 1, 2025.
Grandfathered systems — anyone with all interconnection paperwork submitted to ComEd, Ameren Illinois, or MidAmerican by 5:00 p.m. on December 31, 2024 — keep full-retail net metering for 30 years from their permission-to-operate date. Every exported kWh is credited at the full retail rate, supply and delivery both.
New systems interconnected after that date get "supply-only" net metering instead: exports are credited only against the electric supply charge, roughly 6.8 to 8 cents per kWh, not delivery, transmission, or fixed charges. That's a real cut versus the old rule, which is why 2026 system design now favors sizing for self-consumption over oversizing to sell power back. Net metering is separate from Illinois Shines — a homeowner installing today gets both the supply-only bill credit and a separate SREC payment for the same system; they stack, neither replaces the other.
Why Your Neighbor's Solar Deal Looks Different
Illinois homeowners talk about one date more than any other: when they got permission to operate. A neighbor grandfathered before December 31, 2024 is locked into full-retail net metering for 30 years; anyone connecting today gets supply-only credit instead. Two visually identical rooftop systems installed a year apart on the same block can have meaningfully different payback purely because of that cutoff — it's the first question people ask in Illinois solar Facebook groups. It also matters which utility you're in: ComEd covers most of northern Illinois, Ameren serves central and southern Illinois, and MidAmerican covers a small slice of the northwest corner, and each runs its own Illinois Shines block openings.
How to Go Solar in Illinois
Work through these steps in order before you commit.
- Pull your last 12 power bills and find your average monthly cost — the higher it is, the more a system can realistically save you.
- Check that your roof faces south, east, or west with minimal shading; north-facing or heavily shaded roofs rarely pay off at Illinois's lower sun angle.
- Confirm your roof has 10 to 15 years of life left, or replace it first — see our roofing guide.
- Get at least three quotes reflecting 2026 reality: no phantom federal credit, and the correct net-metering track (grandfathered vs. supply-only) for a new interconnection.
- Get your Illinois Shines SREC value quoted in writing, and ask whether the new 7-year payment schedule (effective June 1, 2026) applies to your system.
- Ask about the $300/kW Distributed Generation rebate and file for the county property-tax alternate valuation once installed.
- Confirm with your insurer how panels affect your policy, and check your panel capacity — see our electrical guide.
For the full picture of how panels work, sizing, and buying versus leasing, read our main solar panels guide. It covers the technology and the decision in depth, while this page focuses on what's specific to Illinois.
Sources
Figures on this page are 2026-current and come from primary and industry sources. Rates: US EIA, Electric Sales, Revenue, and Average Price (2025 values preliminary). Production estimates: NREL PVWatts. Net metering cutover: Ameren Illinois — Net Metering and Illinois Shines — Net Metering Changes FAQ. SREC program and pricing: Illinois Shines Program Updates and DSIRE — Adjustable Block Program. Property tax treatment: 35 ILCS 200/10-10 and Illinois Department of Revenue. Cost data: EnergySage — Illinois Solar Panel Cost. Federal credit repeal: IRS Residential Clean Energy Credit guidance (P.L. 119-21). We review these figures every six months.