Compare solar cash purchase, loan, lease and PPA using shared production assumptions. Review lifetime payments, escalators and benefits without a sales signup.
Quick answer
Ownership benefit = energy value minus installation, financing and recurring costs; lease/PPA benefit subtracts contract payments instead.
Notes updated 2026-10-06
- Best for
- Homeowners pressure-testing solar proposals before signing.
- Inputs needed
- electric usage, local rate, system size or quote assumptions
- Formula used
- Ownership benefit = energy value minus installation, financing and recurring costs; lease/PPA benefit subtracts contract payments instead.
- Method references
- CFPB solar financing guidance, System Advisor Model
How do I compare solar ownership paths fairly?
Use the same system output, household usage and rate assumptions for cash, loan, lease and PPA options. Review escalators, maintenance obligations, transfer terms and total payments rather than selecting the smallest starting bill.
Who should verify contract and incentive terms?
Read the actual offer and confirm eligibility with the provider and relevant authority. A lease or PPA does not establish commercial credit eligibility or guarantee that a benefit is passed through to the customer.
How does this lease vs buy solar estimate work?
Ownership benefit = energy value minus installation, financing and recurring costs; lease/PPA benefit subtracts contract payments instead.
A worked example with explicit assumptions
A $150 monthly lease with a 2% annual escalator costs $1,800 in year one and $1,800 x 1.02^9 = $2,151 in year ten. Compare that payment path with energy value, not only the starting payment.
What should I verify before using the result?
Transfer clauses, buyout schedules, roof-work obligations and provider eligibility can change the practical result.
Use your bill or written equipment quote, run a conservative scenario, and compare the result with the same inputs in another model.
References and next steps
Calculation notes updated 2026-10-06. Reference links explain the method; they do not establish a current utility tariff or installer price.
Read the full methodology or save and compare your solar plan.
How does a PPA escalator compound?
Multiply the initial energy price by (1 + escalator) raised to the number of annual increases. Separate PPA payments from utility charges.
Worked example: An illustrative $0.12/kWh PPA with 3% yearly increases is $0.15657/kWh after nine increases, approximately $0.157 in year 10.
What to verify: Check contract anniversary dates, produced-energy billing, buyout and transfer conditions.
Method reference (not verification of example prices)Planning notes updated October 12, 2026. Example assumptions are not a local tariff.
Pressure-test the estimate
Treat the result as a planning range, not a promise. Re-run it with a lower and higher production estimate, your actual utility tariff, and the written installer quote.
- Check roof shade, orientation, tilt, and equipment losses.
- Separate cash price, financing fees, battery cost, and roof work.
- Verify export credits, fixed charges, and interconnection rules.
- Confirm incentive eligibility, deadlines, and tax treatment.
Sources behind this estimate
Use the method references below to check the formula and its limitations. Input defaults and illustrative scenarios are not current tariffs, guaranteed output or live installer quotes.
Utility export rates, eligibility rules, and installer pricing can change. Confirm the applicable tariff, interconnection requirements, and tax treatment before making a purchase decision.
Frequently asked questions
How do I use the lease vs buy solar calculator?+
Start with your actual usage, equipment or quote inputs, keep the displayed units, and change one assumption at a time. Transfer clauses, buyout schedules, roof-work obligations and provider eligibility can change the practical result.
What calculation does this tool use?+
Ownership benefit = energy value minus installation, financing and recurring costs; lease/PPA benefit subtracts contract payments instead.
Can I check the arithmetic with an example?+
A $150 monthly lease with a 2% annual escalator costs $1,800 in year one and $1,800 x 1.02^9 = $2,151 in year ten. Compare that payment path with energy value, not only the starting payment.
What could change the accuracy of my result?+
Transfer clauses, buyout schedules, roof-work obligations and provider eligibility can change the practical result.
Can I use the estimate outside the United States?+
Physical kW and kWh calculations use the same units internationally. Dollar results, regional defaults, emissions factors, incentives and utility guidance are US-oriented. Replace rate and production assumptions with local values; do not apply US tax or export rules abroad.
Can I print or save results without registering?+
Use Print / PDF to save this page from your browser without an email address. The solar plan stores supported scenario inputs in your browser; private files should be checked and redacted before uploading for extraction.
Compare the decision, not just the number
Compare cash, loan, lease, and battery scenarios using the same production, rate, and quote assumptions before choosing a financing path.
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