Solar in Madison County, Illinois: what to know first

Can GSM Solar help a home in Madison County? Yes, if you own the home, it is in the Ameren Illinois service territory, and it fits. Some homes here get power from an electric co-op or a city utility instead. GSM Solar can't help those homes. For the rest, your roof, the shade on it and the local permit rules decide what comes next.

Which power company serves your home?

Look at the top of your power bill. The company named there is your utility, and it decides whether GSM Solar can help. GSM Solar works only with homes in the Ameren Illinois service territory. GSM Solar is not affiliated with Ameren Illinois, any co-op or any city utility, and none of them runs or backs its offer.

Three electric co-ops say on their own websites that they serve part of Madison County. A co-op is a power company owned by the people it serves.

• Southwestern Electric Cooperative says it serves parts of Madison County, along with parts of several nearby counties.
• MJM Electric Cooperative says it has power lines in Madison County, among the counties it serves.
• Clinton County Electric Cooperative says it serves parts of Madison County too.

If one of these co-ops sends your bill, GSM Solar can't help with solar. Their websites list counties, not streets, so your bill is the surest check.

A co-op also sets its own solar rules. Illinois Shines says co-ops and city utilities may limit net metering or credit power a different way. Net metering is how a utility credits the power your panels send back. If a co-op serves you, ask it how it handles solar before you talk to anyone selling it.

Some Illinois towns run their own city utility. If a city's name is on your bill, the same holds: GSM Solar can't help, and the city's own rules apply.

For homes in the Ameren Illinois service territory, net metering is a credit on your bill for the power your panels send to the grid. A system that starts on or after January 1, 2025 gets credit for supply charges only. Our guide to net metering in Ameren Illinois explains what that credit covers. Either way, you stay a utility customer, responsible for a utility bill.

How much sun does Madison County get?

The Department of Energy points homeowners to PVWatts, a tool from a national lab that estimates how much power a solar system makes at any address. We ran it for one kW of panels on a south-facing roof in Edwardsville, the county seat. It models about 1,395 kWh a year per kW. A kWh is the unit your power bill counts.

In this model, June makes the most power and December the least. Winter days are short, so the same panels make less. A bigger system makes about that much for each kW it has.

A model is not a measurement. It assumes a roof that faces south with no shade. An east or west roof makes less, and so does a roof under trees. Before you sign anything, ask for a custom estimate for your own system, from a solar installer. Our page on whether your home is a fit walks through roof direction and shade.

Who issues the building permit?

It depends on where the home sits. Outside city and village limits, in what the county calls unincorporated areas, the county handles it. Madison County's own page says the county Building & Zoning Department runs the building code for unincorporated areas, and a contractor applies for the permit before work starts.

Its permit list has separate permit applications for roof mount solar and ground mount solar, which can be filled out and sent online. Work may begin once the Building Inspector approves the application and you receive your Madison County building permit.

So the company doing the work is the one that applies. Ask it for the permit before anyone climbs on your roof, and keep a copy with your contract.

Inside a city or village, ask that town's city hall which permits it needs. Edwardsville spells its rules out in writing, so they are below.

What does Edwardsville ask for?

The City of Edwardsville requires a building permit for every home solar installation, before any work begins. The application needs more than a drawing of where the panels go.

For panels on a roof, the city wants a sealed analysis or drawing from an Illinois licensed architect or structural engineer showing the roof can carry the weight. It also wants room for firefighters to cross the roof around the panels: at least two clear paths, each 36 inches wide, on separate parts of the roof.

The city puts one question back on the homeowner. Its rules say it is the owner's job to weigh the roof's remaining life against the panels', since the panels may outlast the roof. The city's sheet adds that a new roof would most likely cost more with panels in place. If your roof is close to needing work, think about that first.

You may live outside Edwardsville. These are still fair questions for any company: who checked that your roof can hold the panels, and how a firefighter would get across it.

How do you check the company and the program?

Illinois Shines is a state program that provides an incentive for solar projects. See how Illinois Shines works for what it is and what it isn't.

Before you sign with anyone, look the company up. Our guide on how to check a solar company in Illinois shows the public lists and what each one tells you.

Every number on this page opens its source when you tap it. All of them are also on our data page.

Quick answers

Can GSM Solar help my Madison County home?

It can if you own the home and it is in the Ameren Illinois service territory. If an electric co-op or a city utility sends your bill, GSM Solar can't help.

Which electric co-ops serve parts of Madison County?

Southwestern Electric Cooperative, MJM Electric Cooperative and Clinton County Electric Cooperative each say on their own websites that they serve part of the county.

Who issues the solar permit outside city limits?

The Madison County Building & Zoning Department. It has its own permit applications for roof mount solar and ground mount solar.

Does Edwardsville need a permit for home solar?

Yes. The city requires a building permit for every home solar installation, and the permit has to come before any work begins.