OneTool

Solar Panel Payback Period Estimator

Simple payback period plus a lifetime savings view, with degradation.

Simple payback period: 12.5 years

First-year savings: $1,600.00

Cumulative net savings (production − system cost, with degradation)

  • 10 years

    -$4,355.24

  • 20 years

    $10,524.65

  • 25 years

    $17,689.52

What is this tool?

Simple payback = system cost ÷ first-year savings (annual production × rate). Cumulative net savings at 10/20/25 years extends that by applying a yearly production-degradation rate — panels produce slightly less each year, commonly cited around 0.5%/year, though your panel warranty's figure is authoritative. Annual production is a number you enter yourself; this tool does not calculate it from your location, roof, or weather data.

How to use it

  1. Enter total system cost and your estimated first-year annual production in kWh.
  2. Enter your current electricity rate and, optionally, adjust the degradation rate.
  3. Read the simple payback period and cumulative net savings at 10, 20, and 25 years.