Calculator
Solar Payback Calculator
For consumers, students & professionals. Result, assumptions, chart, comparisons and recommendations.
Unit system— all inputs and outputs convert automatically
Inputs
Enter your data — results update live.
Payback period
14.9
years
Notes
- • Break-even in year 15. After that, every kWh is profit.
- • Assumes 3%/yr electricity inflation and 0.5%/yr panel degradation.
Breakdown chart
Visual comparison of each component (kWh).
- Year-1 generation
- 8377.00 kWh
- Year-1 savings
- 1005.00 $
- 25-yr generation
- 197322.00 kWh
- 25-yr savings
- 34269.00 $
- 25-yr net profit
- 19269.00 $
- Lifetime ROI
- 128.50 %
- 25-yr CO₂ avoided
- 78929.00 kg
- Equivalent trees planted
- 3588.00 trees
Methodology & sources
Formula
AC kWh = kW·sun·365·derate; savings = self·rate + export·feed; payback = cost / year-1 savingsSources
- • NREL PVWatts v8
- • IEA PV Roadmap 2024
- • SunPower & LBNL LCOE studies