☀️YourWattsUS
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Solar ROI Calculator

Know exactly what your solar investment returns — production in kWh, annual savings, payback year, 25-year net savings, and your CO₂ impact. The numbers are more compelling than the marketing.

Your System Details

Annual Production

15.2 MWh

Year 1

Year 1 Savings

$1,974

Payback: 11 years

25-Year Net Savings

$26,498

After full system cost

CO₂ Offset

138.1 tonnes

≈ planting 6,574 trees

25-Year Cumulative Net Savings

Assumes 0.5%/year panel degradation and flat electricity rate of $0.13/kWh. Actual results vary.

How this calculator works

  • • Annual production = system kW × peak sun hours (by state) × 365 days × 0.80 performance ratio
  • • Annual savings = annual production × your electricity rate
  • • Payback year = net cost (after incentives) ÷ annual savings
  • • 25-year projection uses 0.5%/year panel degradation (industry standard)
  • • CO₂ offset based on US average grid emission factor of 0.386 kg CO₂/kWh

Results are estimates. Actual production varies with shading, weather, and equipment performance. See our methodology for full calculation details.