01 · Browse by topic
Browse by topic
Bills & RatesWhy bills rose, what’s normal, and solar’s effect9Your Home & RoofFit, size, roof, permits and your city11Costs & BuyingCosts, quotes, leases and loans6Incentives & ProgramsPrograms that pay, and who gets paid6Batteries & Virtual Power PlantsBackup, rebates and their strings6Guides & ReferenceBig-picture guides and key figures2
02 · Where do I start?
Where do I start?
Pick the one that sounds like you. Each path walks through the guides in order.
My electric bill is too high
For anyone whose bill jumped and wants to know why.
I’m new to solar
Start here if you’re wondering whether solar makes sense.
I have a solar quote
Check it before you sign anything.
I want backup power
For homes that can’t afford to lose power.
I already have solar
Get the most from the system you have.
I’m an Ameren customer
Central and southern Illinois homes start here.
03 · Free tools and calculators
Free tools and calculators
Run your own numbers. Every tool works in your browser, and nothing you type is stored.
Lease-or-buy cost calculatorCompare cash, loan, lease and PPA by monthly cost.Electric bill builderBuild your ComEd or Ameren bill line by line.Solar payback calculatorSee how long solar takes to pay for itself.Then-vs-now bill calculatorSee how much more your bill costs than in 2024.60-second house-fit checkerFind out if your roof and home suit solar.Battery decision checkFive questions to see if a battery fits you.Solar quote checkerCheck a quote’s price per watt against the norm.Dealer-fee calculatorEstimate the fee hidden in a solar loan.Hourly Pricing calculatorCompare fixed, hourly and battery setups on ComEd.Winter output toolSee solar output month by month in five cities.Aurora permit fee calculatorEstimate Aurora’s solar permit fee.
Know before your bill changes
Get a short email when ComEd or Ameren prices or key solar programs change. About 4–6 a year, nothing else.
Want answers for your own home?
Free, about a minute, no obligation. If rooftop solar isn’t right for your home, it tells you so.
04 · All 40 guides by topic
All 40 guides by topic
Within each topic, guides run from the first question most people ask to the deeper ones.
Bills & Rates
Why bills are high, what’s normal, and what solar changes on your bill.
- What is the average electric bill in Illinois?UpdatedWhat homes like yours pay each month, line by line, with a bill calculator.
- Why is my ComEd bill so high?UpdatedThe price increases behind ComEd bills, and what you can do about them.
- Why is my Ameren bill so high?UpdatedWhy Ameren bills jump in summer, and what changes in winter.
- Illinois electric rate trackerUpdatedEvery ComEd and Ameren price change since 2024, with a then-vs-now calculator.
- What changed on October 1?UpdatedComEd’s new price for fall and winter, and what it means for your bill.
- Can Hourly Pricing and solar get your bill to $0?UpdatedHow ComEd’s hourly credits work, and when a zero bill is possible.
- Will I still get an electric bill after solar?UpdatedWhat goes away with solar, and what stays on your bill.
- ComEd net metering, explainedUpdatedHow ComEd credits the power your panels send back to the grid.
- Ameren net metering, explainedUpdatedHow Ameren credits the power your panels send back to the grid.
Your Home & Roof
Whether your house fits solar, how big to go, and the rules where you live.
- Is my house good for solar?NewAn eight-point check of your roof, shade and electrical panel, with a 60-second checker.
- How many solar panels do I need?How to size a system from your own electricity use.
- What does your roof need for solar?Roof age, direction and condition, and when to replace it first.
- Is your roof too shaded for solar?How shade affects output, and your options if it’s heavy.
- Do solar panels work in an Illinois winter?NewMonth-by-month output in five cities, plus snow and outages.
- Do solar panels survive hail?Hail ratings, insurance and what warranties cover.
- Can an HOA block solar panels?What Illinois law lets an HOA require, and what it can’t.
- Do you need a permit for solar in Chicago?Chicago’s permit steps and fee rules, explained.
- How do solar permits work in Aurora?Aurora’s permit process, with a fee calculator.
- Solar panels in PeoriaCosts, permits and Ameren rules for Peoria-area homes.
- Selling a house with solarWhat buyers ask, and how owned and leased systems transfer.
Costs & Buying
What solar costs, how to pay for it, and how to check a quote before you sign.
- Is solar worth it in Illinois?UpdatedThe honest payback math for your home, with a calculator.
- How much does solar cost in Illinois?UpdatedWhat a typical system costs before and after incentives, with a quote checker.
- Lease or buy solar?UpdatedCash, loan, lease and PPA compared by monthly and 25-year cost.
- Is my solar quote a good deal?The checks that separate a fair quote from a bad one.
- Why is my solar loan bigger than the cash price?Hidden dealer fees, how to spot them, and a fee calculator.
- Is my solar installer legit?How to check an installer on the state’s official list.
Incentives & Programs
Which programs pay for solar, who gets the money, and what to get in writing.
- Every Illinois solar incentiveUpdatedAll the programs in one place, and who gets each one.
- Illinois Shines, explainedHow the state pays for your solar power, and where the money goes.
- The ComEd solar rebateUpdatedHow the rebate works, when it’s paid and how to apply.
- Did the solar tax credit end?What changed in 2026, and who can still claim a credit.
- Does Illinois have a state solar tax credit?The common myth, and the real Illinois benefits.
- Does solar raise your property taxes?The Illinois protection, and the form to file.
Batteries & Virtual Power Plants
Whether a battery is worth it, the rebates, and what they commit you to.
- Is a home battery worth it?UpdatedThe honest math, backup vs. savings, and a five-question check.
- Illinois battery incentives, explainedUpdatedEvery battery rebate and program, and what each one requires.
- The ComEd battery rebateUpdatedWhat the rebate pays and what it commits you to.
- ComEd’s virtual power plantUpdatedHow ComEd will pay batteries for summer power, and the rules.
- Ameren’s virtual power plantUpdatedAmeren’s battery program and rebate terms.
- Free home battery offers, explainedUpdatedHow $0-down battery deals work, and the catch.
Guides & Reference
The big-picture guides, with every key figure in one place.
05 · What changed recently
What changed recently
Update log · last updated October 1, 2026
- Library rebuilt for homeowners, with starting paths, a free-tools section and a plain-English line for every guide. New: is my house good for solar? Rebuilt this week: the rate tracker, the lease-or-buy calculator, the average bill, the battery math, solar costs, both bill guides, both net-metering guides, the ComEd solar guide and the payback calculator.
- October prices were published and added across the rate, battery and incentive guides. Batteries got their own section.
- New guide: solar in an Illinois winter. The ComEd solar rebate guide was re-checked against state law.
- Eight guides re-checked against both utilities’ published virtual power plant rules.
- ComEd’s January transmission update, virtual power plant sign-ups in spring 2027, a standalone battery rebate, and battery-only net metering starting January 1, 2027. Each lands here the day it’s published.
- New guide: solar panels in Peoria.
- Five new guides: Hourly Pricing and solar, dealer fees, verifying an installer, Aurora permits, and the state tax credit myth.
- Five new guides: solar costs, Chicago permits, Ameren bills, Ameren’s virtual power plant and free battery offers. Corrected the interconnection fee across the library.
- Five new guides: system size, quote vetting, your bill after solar, the October rate reset and whether a battery is worth it.
- First plain-English guide to ComEd’s virtual power plant.
- Six Home & Roof guides published.
Where to next
Most read
By Google clicks over the last 28 days, checked September 28, 2026.
Not sure where to start? Start with your address.
Free, about a minute, no obligation. If rooftop solar isn’t the right fit, it says so instead of handing you to a salesperson.
Free eligibility check · ComEd & Ameren · No obligationThe Day Company is an Illinois solar and battery information resource and a lead-generation business. Information you submit may be used by our review team and one authorized partner to contact you about your request. Checking eligibility creates no obligation, and nothing on this site is a quote or a guarantee. How we’re funded and how we source figures: our editorial standards.
Sources and updates
Where our figures come from
Primary sources · 8 sources used across this library
- Illinois Commerce Commission — utility tariffs and orders
- Plug In Illinois — utility supply prices
- Illinois Shines — program prices and rules
- Citizens Utility Board — rate alerts and guides, cited as advocacy research
- U.S. Energy Information Administration — electricity use and prices
- Lawrence Berkeley National Laboratory — solar and battery prices
- National Renewable Energy Laboratory — solar output and battery modeling
- Internal Revenue Service — federal tax credit rules
How to cite this page: The Day Company, "Illinois Solar and Battery Answers", theday.company/answers, last reviewed October 1, 2026.
Changelog · last updated October 1, 2026 · 14 updates
- October 1, 2026 — v16: redesigned for easier reading and navigation: a search-first top section, topic tiles with icons and colors, a sticky topic bar, icons on every path and tool, quieter update labels, rate-change email alerts, a “pick up where you left off” card, and the share row moved to the end.
- October 1, 2026 — v15: new site search: searches every guide, section and FAQ question, fixes typos with “did you mean,” suggests as you type, remembers recent searches, makes searches shareable by link, and supports voice. The search index refreshes daily on its own, so renamed and new guides appear automatically.
- September 29, 2026 — v14: rebuilt for homeowners. Removed the answer table and price spotlight so each guide owns its own answer; added starting paths, 11 free tools and a one-line summary for every guide, ordered from first question to deeper ones; added the house-fit guide and seven core guides (40 total); site-wide footer update, tap-to-open log and changelog.
- September 28, 2026 — v13: batteries got their own section; October prices added; average-bill and winter guides added (32 total).
- September 17, 2026 — v12: eight guides re-checked against both virtual power plant tariffs; share row, jump links and reading bar added.
- August 8, 2026 — v11: Peoria guide added (30 total).
- August 7, 2026 — v10: two guides re-dated after updates.
- August 6, 2026 — v9: Hourly Pricing guide added (29 total).
- August 6, 2026 — v8: four guides added (28 total).
- August 3, 2026 — v7: five guides added (24 total); interconnection fee corrected.
- August 1, 2026 — v6: byline, update log and mid-page check added.
- July 30, 2026 — v5: five guides added (19 total).
- July 21, 2026 — v4: virtual power plant guide and four incentive guides added.
- July 18, 2026 — v3: Home & Roof guides, question chips and topic facts added.
Update triggers: this library is updated when a guide is added or rebuilt, and when utility prices or program rules change.
Independent by design — a resource, not a utility, installer or supplier.About usHow we verify figuresReport an error