The Solar Reality Check. Run The Numbers.
Plug in a few numbers from your bill. We'll show you what your system really costs and whether you're saving money or losing it.
Pick How You Paid For Your System.
The math is different for each one. Pick the one that matches your contract. Not sure? Check your most recent solar bill or your loan statement. The form will tell you what to look for.
Quick tip: If you have a monthly payment that says "GoodLeap," "Mosaic," "Sunlight Financial," or "Dividend" on it, you have a loan. If your payment says the solar company name (Sunrun, SunPower, Vivint, etc.), it is most likely a PPA or lease.
How do I know which one I have? (Open for a checklist)
You have a Solar Loan if:
- You make a monthly payment to a lender like GoodLeap, Mosaic, Sunlight Financial, Dividend Finance, Cross River Bank, or your own bank.
- Your contract uses words like "loan," "financed," "APR," "principal balance," or "amortization."
- You will own the system outright when the loan is paid off.
- You probably claimed a 30% federal tax credit on your taxes the year of installation.
You have a PPA or Lease if:
- You pay the solar company directly each month (Sunrun, SunPower, Vivint, Sunnova, Trinity, etc.) — not a separate lender.
- Your contract uses words like "PPA," "Power Purchase Agreement," "lease," "rate per kWh," or "monthly service fee."
- Your contract has an annual escalator (often 1.9% to 3.9% per year).
- The solar company still owns the panels on your roof. You do not.
- The contract usually runs 20 or 25 years.
- You did NOT get the federal tax credit. The solar company kept it.
You paid Cash if:
- You paid the full price up front, often with a check, wire, or HELOC.
- You have no monthly solar payment, only your utility bill.
- You own the system outright.
- You probably claimed the 30% federal tax credit.
Still not sure?
- Pull your most recent bank statement. Look for any recurring charge from a solar or finance company.
- If you cannot find a contract or any payment, you may have signed a PPA or lease where the only bill is rolled into your power. Take the Free Solar Relief Assessment and a counselor will help you figure out what you signed.
Solar Loan — The Numbers
All of these are on your loan statement and your most recent electric bill. Round to the nearest dollar. We'll handle the rest.
PPA or Lease — The Numbers
Find these on your most recent solar bill and your electric bill. The escalator is in your contract, often on page 14.
Paid Cash — The Numbers
You paid up front, so the math is simpler. We just need to know what you paid and what you saved.
What A Reality Check Looks Like.
Here is a sample loan customer who got a fair deal. Reasonable system price. Mid-range APR. Real monthly savings. The reality check shows the lifetime math actually works in their favor.
Three Numbers. Five Minutes. Honest Answer.
Pick Your Deal Type
Loan, PPA or lease, or cash. The math is different for each one.
Plug In A Few Numbers
Your bill, your payment, the basics. All on your most recent statement.
Get Your Reality Check
What the system really costs. Whether you are saving or losing. What to do next.
Heads Up — A Couple Numbers Look Unusual
We just want to make sure nothing got typed in the wrong field. Take a look:
Your numbers may still be right. Click "Run Anyway" to use them as entered, or "Fix My Inputs" to go back and check.
How We Calculate & Grade The Reality Check
The Solar Reality Check uses publicly known industry figures and your own bill. No marketing math, no inflated promises.
The Letter Grade
We compare what you would pay if you stayed on the utility against what you actually pay with solar, over the full horizon, then express the gap as a percentage:
- A: Lifetime savings of 20% or more vs. the utility.
- B: Lifetime savings between 5% and 20%.
- C: Roughly even (within 5% either way).
- D: Lifetime loss between 5% and 20%.
- F: Lifetime loss of more than 20%.
Industry Assumptions
- Utility rate inflation: 4% per year. The U.S. Energy Information Administration's 25-year residential average is about 2.85% per year. We use 4% to blend the long-run history with the post-2022 acceleration (2022 was about 11%, 2023 about 5.7%, 2024 about 3.1%).
- Panel degradation: 0.5% per year. NREL median for residential silicon panels. By year 25 your panels produce about 88% of year-1 output, which means your utility bill grows over time even with a flat rate. We model this in all three modes.
- Time horizon: 25 years (or your loan term, whichever is longer). Matches the standard solar production warranty and typical panel lifespan. For a 30-year loan we extend the comparison to 30 years so the math is fair.
For Loan Customers
- Hidden dealer fee estimate: 25% of system price. State attorney general filings put the typical range at 15% to 30%. We use 25% as the mid-range. Sources: Minnesota AG Ellison's March 2024 lawsuit against GoodLeap, Sunlight Financial, Mosaic, and Dividend (cited 15-30%); New York AG James's March 2026 lawsuit against Attyx and Mosaic (cited 20-30%).
- Monthly payment: Standard amortization formula based on your loan amount, APR, and term.
For PPA and Lease Customers
- Escalator math: Your monthly payment grows by your contract escalator each year. Compounded.
- Many PPA customers still pay a utility bill on top of their solar payment. The calculator captures that, and grows it as panels degrade.
For Cash Customers
- Simple payback: System price divided by year-1 annual savings. We label it "year-1 dollars" because real payback is faster once you account for utility inflation.
- Lifetime value: Annual savings, projected forward with utility inflation and panel degradation, over the 25-year horizon.
The Reality Check is an estimate based on the numbers you provide and standard industry assumptions. Your actual results will vary. For a contract-specific review, take the Free Solar Relief Assessment.