Finance tool

Payback & ROI Calculator

Net cost and honest first-year savings in — break-even year and lifetime return out. Get your inputs from the Solar Savings Calculator or a real quote.

Net system cost (after all incentives)

First-year electricity savings

Default: typical annual usage at the latest national EIA residential rate for April 2026; replace it with quote-specific savings.Utility rate escalation (%/yr)

Break-evenyear 9.5

25-year savings$64,886

25-year net gain$43,886

Lifetime ROI209%

Models 0.5%/yr panel degradation and your escalation input, year by year, over a 25-year warranty life. Inverter replacement (typically $2,000–$3,000 in years 10–15 for string inverters) is not included.

Reading the result

The method, worked examples, and what lengthens payback (dealer fees, weak export rates, shading) are in the payback guide. As a screening rule: paybacks comfortably inside the 25-year warranty life are sound; paybacks beyond ~15 years deserve the skeptical checklist.