Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Lower net cost option
Buy
Buy net cost (20yr)
-$29,851
Lease/PPA total cost (20yr)
$35,110
Difference
$64,961
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How to use this
- 1Enter system purchase price ($).
- 2Enter federal tax credit % (%).
- 3Enter monthly electric savings if owned ($).
- 4Enter lease/ppa starting monthly payment ($).
- 5Enter lease annual escalator (%).
- 6Enter system life.
- 7Read your lower net cost option on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Buying solar costs more upfront but you keep 100% of the savings and any tax credit, while leasing (or a power purchase agreement) requires no money down but locks you into an escalating payment and forfeits ownership incentives. This tool compares total cash outlay over a typical 20-year system life: purchase price minus incentives and electricity savings, versus total lease payments with an annual escalator, minus the smaller savings a lease still provides.
Worked example
Using the values the calculator loads with:
Inputs
- System purchase price: 24000 $
- Federal tax credit %: 30 %
- Monthly electric savings if owned: 160 $
- Lease/PPA starting monthly payment: 110 $
- Lease annual escalator: 2.9 %
- System life: 20
Results
- Lower net cost option: Buy
- Buy net cost (20yr): -$29,851
- Lease/PPA total cost (20yr): $35,110
- Difference: $64,961
What each field means
Inputs
- System purchase price ($)
- The system purchase price used in the calculation, measured in $. Starts at 24000 $ so you have a working example on load.
- Federal tax credit % (%)
- The federal tax credit % used in the calculation, measured in %. Starts at 30 % so you have a working example on load. Accepted range: 0–50 %.
- Monthly electric savings if owned ($)
- The monthly electric savings if owned used in the calculation, measured in $. Starts at 160 $ so you have a working example on load.
- Lease/PPA starting monthly payment ($)
- The lease/ppa starting monthly payment used in the calculation, measured in $. Starts at 110 $ so you have a working example on load.
- Lease annual escalator (%)
- The lease annual escalator used in the calculation, measured in %. Starts at 2.9 % so you have a working example on load. Accepted range: 0–10 %.
- System life
- The system life used in the calculation. Starts at 20 so you have a working example on load. Accepted range: 5–30.
Results
- Lower net cost option
- Returned as a plain value and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Buy net cost (20yr)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lease/PPA total cost (20yr)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Difference
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why does buying usually win long-term?
Because you capture the 30% federal tax credit and 100% of electricity savings instead of splitting them with a leasing company, and once paid off the system produces free power for years.
When does a lease make sense?
If you can't use the tax credit (low tax liability), don't have upfront cash, or plan to move before the system pays for itself, a lease avoids upfront risk at the cost of long-run savings.
Does leasing affect selling my house?
Yes — most leases must be transferred to the buyer or paid off at sale, which can complicate a home sale in ways outright ownership doesn't.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Solar Buy vs Lease Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/solar-buy-vs-lease
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/solar-buy-vs-lease" target="_blank" rel="noopener">Solar Buy vs Lease Calculator — RevenueLab</a> (2026).</p>
Source: [Solar Buy vs Lease Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/solar-buy-vs-lease) (2026).