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Solar savings calculator
See what a rooftop system could cost, save and earn over 25 years. Change any assumption and the numbers update instantly.
Cumulative savings, years 1–25
Check this against real quotesHow the calculator works
We convert your bill into yearly kilowatt-hours using your state's average residential price, then size a system to cover your chosen share of that usage. Each kilowatt of panels produces about sun hours × 365 × 0.78 kWh a year. The 0.78 accounts for inverter losses, wiring, heat and dirt.
Savings start at your current price, grow with the yearly price rise you choose, and shrink by 0.5% a year as panels age. A 15% haircut covers the gap between what you use at home and what you export, since many utilities now credit exports at less than the retail price. See net metering explained.
Questions
Why is my real quote different?
Quotes reflect your exact roof angle, shade, local labor and permit costs, and equipment. Use this as a sanity check: if a quote's price per watt is far above $3.50 or the promised savings are far above ours, ask why.
Does this include a battery?
No. Batteries usually add $11,000 to $17,000 and mainly pay off with time-of-use rates or poor export credits. Size one with the battery backup sizer.
Is the federal tax credit included?
No, because the 30% homeowner credit ended for systems installed after December 31, 2025. If your state offers a credit or rebate, add it with the incentives slider. See solar incentives in 2026.