Solar ROI Calculator — Free Online Calculator
Calculate your solar panel return on investment, payback period, and 25-year savings including the federal tax credit.
How to Use This Calculator
Enter total system cost, estimated annual production (from your installer quote), electricity rate, annual rate increase, and tax credit percentage.
The Formula Explained
Net cost = System cost × (1 - tax credit %). Annual savings = Production × Rate × 0.995 (0.5% annual panel degradation). Payback = year when cumulative savings exceed net cost. 25-year savings account for rising electricity rates.