The cost of solar panels in O Fallon, IL (2024)

Updated Nov 19, 2024

  • You'll pay an average of $14,040 to install a 5 kilowatt solar panel system in O Fallon, IL, before incentives.

  • The federal investment tax credit (ITC) lowers that price by 30% of all your solar equipment and installation costs.

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Written by: Emily Walker

As of November 2024, the average solar panel system costs $2.81/W including installation in O Fallon, IL. For a 5 kW installation, this comes out to about $14,040 before incentives, though prices range from $11,934 to $16,146. After the federal tax credit, the average price drops by 30%.

Average price of a 5 kW solar panel installation in O Fallon, IL

Good Price
$11,934 or less
Market Average
$14,040
High Price
$16,146 or more

You'll probably pay even less than what we show here. It doesn't include the federal ITC or O Fallon, IL state incentives, which will lower this price by at least a few thousand dollars.

Your solar panel cost depends on your system's size

It may seem obvious but larger solar panel systems cost more money. We use cost per watt ($/W) so you can easily compare quotes, controlling for slight variations in system size.

While a 5 kW system will only cost you $14,040 in O Fallon, IL, doubling the system size effectively doubles the price, so you'll pay about twice that for a 10 kW system. The higher the price tag, though, the more you'll get back as a credit towards your federal tax bill.

Average solar cost by system size in O Fallon, IL

System Size
System Cost
System Cost (after ITC)
3 kW$8,424$5,897
4 kW$11,232$7,863
5 kW$14,040$9,828
6 kW$16,848$11,794
7 kW$19,657$13,760
8 kW$22,465$15,725
9 kW$25,273$17,691
10 kW$28,081$19,657

Are solar panels worth it in O Fallon, IL?

Solar panels are worth it in most areas, including O Fallon, IL. Certain factors, including the cost of electricity, incentives, climate, and the angle at which the sun hits your roof impact how quickly you break even on your investment relative to other areas around the U.S. 

If you pay for your system with cash, you'll save about $92,978 over 25 years (the warranty term of most solar panels) on electricity costs with a 5 kW system in O Fallon, IL. We generate this estimate based on real solar quote data from our Marketplace. It considers your system's cost, the federal tax credit, and inflation rates.

Payback Period
3.65 Years
25-Year Savings
$92,978
Cost-per-Watt
$2.81

If you can't shell out $14,040 in cash to pay for solar, don't sweat it. You can choose to finance your system with a loan instead. Some companies even offer $0-down loans so you can start saving on day one if your loan payments are less than your current electric bills. Just keep in mind that your long-term savings will be lower with a loan due to interest rates.

Find out what solar panels cost in your area in 2024
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The numbers we're showing are averages. The price you'll pay for solar depends on many factors unique to you and your home:

If you're looking for solar companies in IL, here are some popular suggestions:

  • All Energy Solar
    Multi-state
    Established 2009
    Elite+ Installer
    Our team of industry professionals have been focused on providing long term, trusted relationships since 2009. O...
    Elite+ Installer
    Screened & Verified

    Our team of industry professionals have been focused on providing long term, trusted relationships since 2009. O...
  • SunSent Solar
    Multi-state
    Established 2016
    Elite Installer
    Switch to sunshine with SunSent Solar:

    - Guaranteed Production: We promise your system will produce what we predic...
    Elite Installer
    Screened & Verified
    5.0 /5.0
    58 Reviews

    Switch to sunshine with SunSent Solar:

    - Guaranteed Production: We promise your system will produce what we predic...
  • Solar City STL
    Multi-state
    Established 2021
    Advanced Installer
    Solar City STL is a local, family owned company that has tailored the way we do business to get you the most ince...
    Advanced Installer
    Screened & Verified
    5.0 /5.0
    6 Reviews

    Solar City STL is a local, family owned company that has tailored the way we do business to get you the most ince...
  • Freedom Solar Pros
    Peoria, IL
    Established 2011
    Advanced Installer
    Our main focus is always on quality, both with equipment used and the installation performed. We offer the best w...
    Advanced Installer
    Screened & Verified
    5.0 /5.0
    3 Reviews

    Our main focus is always on quality, both with equipment used and the installation performed. We offer the best w...
  • American Energy Systems
    Multi-state
    Established 2011
    Approved Installer
    At American Energy Systems, our mission is to educate homeowners on the benefits of going solar. We offer customi...
    Approved Installer
    Screened & Verified

    At American Energy Systems, our mission is to educate homeowners on the benefits of going solar. We offer customi...

Solar is a major purchase, but you can get the price tag to come down a bit by being an educated shopper. Taking advantage of incentives and rebates and shopping around for quotes can bring down your cost of solar in O Fallon, IL.

Take advantage of federal and local solar incentives

As long as your federal tax bill is high enough, you can take advantage of the federal tax credit in O Fallon, IL. This incentive allows you to apply 30% of your solar installation and equipment costs toward your federal tax bill. If the amount exceeds your tax bill, you can roll over the remaining credit to the following year. Many states also offer great local incentives and rebates.

Get quotes from multiple installers

Comparing multiple solar quotes can save you money through competition and transparency. Each additional quote you receive for solar will help you find the right solar panel system at the right price.

This is where EnergySage can help. With funding from the Department of Energy’s SunShot Prize, EnergySage opened the country’s first (and now the largest) marketplace for home solar panel installations. We gather custom solar quotes from local installers on your behalf and put them in an easy-to-compare format. When you compare quotes for solar panels on the EnergySage Marketplace, you can expect to see prices up to 20% lower than if you work with a single solar company.

Why shop with EnergySage?

Save time & money

Request free quotes from vetted installers in minutes

Unbiased support

Our expert Energy Advisors will help you make the right decision

Trusted, local installers

We pre-screen and monitor all of our partners

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