This model accumulates annual energy value year by year, increasing the electricity rate and reducing solar output using your assumptions. It does not model loan interest, taxes, time-of-use intervals, export-rate differences, inverter replacement or the time value of money. Use it as a transparent planning model, not a financial guarantee.
Compare solar payback by state first
Before personalizing the assumptions, see how the same standardized 8 kW benchmark changes across all 50 states using current solar pricing, residential electricity rates and planning solar yield.
Which system cost should you enter?
Use the amount you actually expect to pay for solar after incentives you have verified for your project. For a 2026 residential project, Home Solar Atlas does not automatically reduce cost by the old 30% Section 25D federal residential credit.
If you still need a system-size or production estimate, start with the Home Solar Calculator. For a market benchmark, compare the state solar hubs and Real Solar Prices.
Why actual payback can differ
- Solar production varies by roof orientation, shading, weather, soiling and system losses.
- Utility tariffs can value self-consumed and exported electricity differently.
- Financing can add interest or dealer fees that are not represented by a cash project cost.
- Equipment replacement, maintenance and home-sale timing can change long-term economics.
- Electricity-price escalation is uncertain, so it remains an editable assumption.