Solar Panel Payback Calculator
Estimate system cost after credit, yearly savings, and payback year.
Result
Formula
Calculation logicFrequently asked questions
How is solar payback calculated?
Net system cost after credits divided by first-year bill savings, adjusted for panel degradation near 0.5 percent and rate inflation.
What is net metering?
Surplus daytime generation earns credits that offset nighttime imports. Weaker export rates lengthen payback by years.
What system size do I need?
Divide annual kWh by local sun hours times 365. Most US homes land between 5 and 10 kW.
Do panels degrade?
About 0.5 percent per year. Warranties typically guarantee 80 to 90 percent output at year 25.
What incentives apply?
The federal tax credit plus state rebates and SRECs cut net cost. Enter your post-incentive price for an honest payback.
Related calculators
Calculator
Appliance Replacement Savings
Decide repair vs replace with payback math.
Open calculatorCalculator
Heat Pump Savings Calculator
Compare heat pump vs furnace annual cost.
Open calculatorCalculator
Insulation ROI Calculator
Estimate insulation payback from heating savings.
Open calculatorCalculator
LED Savings Calculator
Compare LED vs incandescent annual savings.
Open calculatorWorkspace
Every result shows its math: your inputs, the formula, the numbers.
Save this calculation to return to the inputs, result, and report from your private workspace.
Sign in or create an account to save this calculation.