Updated: August 22, 2026 · Estimated read time: 11 minutes
Imagine putting solar panels on your home without writing a $30,000, $40,000, or $50,000 check.
No traditional solar loan.
No need to purchase the entire system upfront.
Instead, you agree to buy the electricity the solar panels produce.
That's the basic idea behind a Solar Power Purchase Agreement, commonly called a PPA.
For some Illinois homeowners, a PPA can provide a way to switch to solar with little or no upfront investment.
But there's an important catch:
You're not buying the solar panels. You're buying the electricity they produce.
And understanding that difference is essential before signing a 20- or 25-year agreement.
Let's break it down without the sales pitch.
Quick Answer
A solar power purchase agreement, or PPA, lets a third party own the solar equipment while the homeowner buys the electricity it produces under a long-term contract. A PPA may require little or no upfront payment, but homeowners should compare the starting energy rate, annual escalator, total projected contract cost, transfer terms, buyout provisions, utility bill and current Illinois Shines disclosure before signing.
First: What Exactly Is a Solar PPA?
A solar PPA is an agreement between a homeowner and a solar system owner.
The solar company or third-party owner installs a solar system on your property.
Instead of purchasing the equipment, you agree to purchase the electricity generated by that system at a predetermined price per kilowatt-hour (kWh).
Think about it this way:
Traditional electricity
Your utility supplies electricity.
You pay the utility for the electricity you consume.
Solar PPA
Solar panels on your home generate electricity.
You purchase that solar electricity according to the terms of your PPA.
The third-party solar owner generally owns the equipment.
That's why a PPA can sometimes be offered with $0 upfront.
You aren't purchasing a $30,000+ solar system on day one.
You're agreeing to purchase the energy it produces over a long period of time.
Here's a Simple Example
Suppose your solar PPA starts at:
$0.165 per kWh
and your system produces:
12,000 kWh during the first year.
Your approximate first-year solar energy cost would be:
12,000 × $0.165 = $1,980
That's approximately:
$165 per month on average.
Your actual PPA billing can depend on the amount of electricity the system produces and the specific terms of your agreement.
Now compare that with what you would otherwise pay for electricity.
If the solar electricity costs less than the electricity it replaces, the homeowner may see savings.
And that brings us to the most important concept in a PPA.
The Monthly Payment Isn't the Most Important Number
When homeowners receive solar proposals, it's tempting to look for one number:
“What's my monthly payment?”
But with a PPA, another number deserves just as much attention:
Your price per kWh.
If you're currently paying an effective electricity cost of, say, 20¢ per kWh and your solar PPA starts at 16.5¢ per kWh, you're purchasing some of your electricity at a lower starting rate.
But that's only the beginning of the comparison.
You also need to ask:
Does the PPA rate increase every year?
Meet the PPA Escalator
Many solar PPAs include an annual escalator.
An escalator increases your solar electricity price by a specified percentage each year.
For example, imagine your PPA starts at:
16.5¢/kWh
with a:
2.99% annual escalator.
Your rate won't stay at 16.5¢ forever.
Approximately:
Year 1: 16.5¢/kWh
Year 5: 18.6¢/kWh
Year 10: 21.5¢/kWh
Year 15: 24.9¢/kWh
Year 20: 28.9¢/kWh
Year 25: 33.5¢/kWh
Those figures are approximate, but they demonstrate why the escalator matters.
Now comes the million-dollar question:
“Is an escalator bad?”
Not automatically.
The real question is whether the cost of the solar electricity remains attractive compared with the electricity costs you would otherwise face over the same period.
Nobody can guarantee exactly what utility electricity will cost 10, 15, or 25 years from now.
That's why a responsible PPA comparison shouldn't simply say:
“Utility rates always go up, so you'll definitely save.”
Instead, look at multiple scenarios.
What happens if utility rates rise quickly?
What happens if they rise slowly?
What happens if they stay relatively flat for several years?
A good solar proposal should help you understand the possibilities—not pretend to predict the future.
Who Owns the Solar Panels?
This is one of the biggest differences between buying solar and using a PPA.
With a PPA:
A third party generally owns the solar system.
You purchase the electricity generated by it.
That has advantages and tradeoffs.
Because you don't own the system, the system owner is typically responsible for certain operations, maintenance, repairs, and equipment obligations according to the contract.
But it also means you generally aren't entitled to the same ownership-based financial benefits that would apply if you purchased the system yourself.
This is something homeowners should understand clearly before signing.
What Happens to Illinois Solar Incentives?
Illinois makes this especially interesting.
Illinois Shines supports qualifying solar projects through Renewable Energy Credits, commonly called RECs.
But with a PPA, don't automatically assume the REC incentive will arrive as a check made out to you.
Depending on the arrangement, the Approved Vendor or project owner may receive the Illinois Shines incentive and use some or all of its value within the economics of the PPA.
Your Illinois Shines Disclosure Form should explain how incentives associated with the project are handled.
Ask:
Who receives the REC payment?
Is any of that value passed through to me?
Is it already reflected in my PPA rate?
Never assume.
Read the disclosure.
Will I Still Receive an Ameren or ComEd Bill?
Yes.
This is extremely important.
Installing solar through a PPA does not necessarily mean your utility bill disappears.
You can still receive a bill from Ameren Illinois, ComEd, or another electric utility. Review LuNova's Illinois net-metering guide for the billing context.
Your solar system may reduce the amount of electricity you need to purchase from the grid, and eligible excess solar generation sent to the grid may produce net-metering credits according to the applicable utility rules.
But you'll generally have:
Your PPA obligation
plus
Your remaining utility bill.
That's why homeowners should be cautious when someone says:
«“This completely replaces your electric bill.”»
The better question is:
What will I pay for solar + what am I expected to continue paying the utility?
That's the number that matters.
What Happens When the Power Goes Out?
Here's another common misconception:
Solar panels do not automatically mean backup power.
Most standard grid-connected solar systems shut down during a grid outage for safety reasons unless the system includes equipment designed to provide backup capability.
That's where battery storage can come into the conversation.
A PPA may potentially include solar plus battery storage depending on the provider and program.
But don't simply ask:
“Does it have a battery?”
Ask:
What can the battery actually power?
There is a huge difference between backing up:
- Refrigerator
- Lights
- Internet
- A few outlets
and attempting to operate:
- Central air conditioning
- Electric heat
- Electric water heater
- Oven
- Dryer
- EV charger
Battery capacity and system design matter.
What Happens If I Sell My House?
This question should be asked before you sign the PPA, not when a buyer is sitting at your closing table.
Because the solar system is owned by another party and the PPA is a long-term agreement, selling your house may involve additional steps.
Depending on the contract, possibilities can include:
Transferring the PPA to the buyer
or
Buying out the agreement
or another contract-specific arrangement.
Transfer requirements can vary significantly.
Before signing, ask:
Can the PPA be transferred?
Does the buyer have to qualify?
Is there a transfer fee?
Can I purchase the system?
How is the buyout price determined?
What happens if the buyer doesn't want the PPA?
Don't wait 10 years to discover those answers.
PPA vs. Solar Loan: What's the Difference?
LuNova's Illinois solar financing comparison provides a side-by-side overview of cash, loan and PPA structures.
This is where homeowners often get confused.
Both can potentially allow you to install solar without paying the entire system price upfront.
But economically they're very different.
With a solar loan:
You're financing the solar equipment.
You generally become the system owner.
When the loan is paid off, you still own the system.
With a PPA:
You're purchasing the electricity produced by the system.
The PPA provider or another third party generally owns the equipment.
Instead of focusing primarily on a loan interest rate, you're evaluating the PPA's electricity rate, escalator, contract length, production, transfer provisions, buyout terms, and other conditions.
Neither option is automatically better.
They're simply different financial products.
What About Buying Solar With Cash?
Cash ownership is usually the simplest structure to understand.
You purchase the system.
You own it.
The electricity it produces belongs to you.
There is no monthly solar loan or PPA electricity payment.
But there's an obvious disadvantage:
You have to provide the money upfront.
For a homeowner who doesn't want to invest tens of thousands of dollars into a solar system, a PPA can eliminate that barrier.
The question isn't:
“Which solar option is universally best?”
There isn't one.
The question is:
“Which structure makes the most sense for my household?”
Who Might Be a Good Candidate for a PPA?
A PPA may be worth considering if you:
- Want solar without a large upfront investment
- Don't want to purchase the entire solar system
- Prefer paying for solar electricity rather than financing equipment
- Want certain maintenance responsibilities handled by the system owner
- Plan to stay in your home long enough for the agreement to make sense
- Understand the escalator and long-term contract
- Have compared the PPA rate against your current and potential future electricity costs
But a PPA may be less attractive if:
- Owning the system is important to you
- You want to capture available ownership benefits yourself
- You expect to sell your home soon
- You dislike long-term contracts
- The PPA rate or escalator isn't competitive
- Purchasing the system produces better long-term economics for your situation
8 Questions to Ask Before Signing a Solar PPA
Before signing anything, get clear answers to these:
1. What is my starting price per kWh?
Don't look only at the estimated monthly payment.
2. Does my rate increase every year?
If so, what's the escalator?
3. How long is the agreement?
20 years? 25 years? Something else?
4. Who owns the system?
Know exactly which company you're entering into the agreement with.
5. Who handles repairs and maintenance?
And which expenses could still become your responsibility?
6. What happens if I sell my house?
Understand transfers and buyouts before signing.
7. What happens at the end of the agreement?
Can you purchase the system? Renew? Have it removed?
8. What am I projected to pay over the entire contract?
This might be the most overlooked question of all.
A low first-year payment doesn't tell you the total cost of a 25-year agreement.
Illinois Gives You an Important Consumer-Protection Tool
Illinois homeowners considering solar through Illinois Shines should receive a Disclosure Form before signing the solar contract.
There are different disclosure forms for purchases, leases, PPAs, and community solar.
For a PPA, the disclosure is designed to help you understand important information about the project and agreement.
Read it.
Don't treat it like another electronic document that just needs a signature.
Compare the disclosure with the sales proposal.
If the salesperson told you something important that you can't find in the agreement or disclosure, ask them to show you where it's written.
A verbal promise and a contractual obligation aren't the same thing.
So... Is a $0-Upfront Solar PPA a Good Deal?
It can be.
But “$0 upfront” doesn't mean “free solar.”
You're entering into a long-term agreement to purchase electricity produced by a solar system located on your property.
That arrangement can potentially provide attractive economics for some homeowners.
For others, purchasing the system may make more sense.
The key is comparing the numbers.
Don't ask only:
“What will solar cost me next month?”
Ask:
“What am I agreeing to over the next 20 or 25 years?”
That's where you'll find the real answer.
See What Solar Could Look Like for Your Illinois Home
At LuNova Solar, we believe homeowners should understand their solar options before being asked to choose one.
Cash.
Solar financing.
PPA.
Solar only.
Solar + battery.
Each option has different advantages, tradeoffs, and long-term economics.
The right place to start is your own home and electricity usage—not a generic sales pitch.
Use LuNova Solar's preliminary solar estimator to explore your home's potential system size, estimated production, energy offset, and solar options.
Then compare the numbers.
Because $0 upfront is only one number.
The next 25 years matter, too.
This article is for general educational purposes and does not constitute financial, tax, or legal advice. Solar programs, utility tariffs, incentives, financing terms, and eligibility requirements can change. Review your actual agreement and current Illinois Shines disclosures before making a decision.
Related Illinois Solar Guides
Sources & References
- U.S. Department of Energy — Homeowner's Guide to Solar — ownership, loans, leases and PPAs
- Illinois Shines — Program Documents — current purchase, lease and PPA disclosure forms
- Illinois Shines — Consumer Protection Resources — current Illinois program requirements