Solar Panel Savings Simulator
Find out what a rooftop solar system is really worth. Pick your region’s sun profile, system size, roof direction and tilt, household consumption and, optionally, a home battery, and the simulator builds an hour-by-hour year: solar production follows the seasonal sun, your usage follows a realistic daily profile, and every kilowatt-hour is routed — used directly, stored in the battery or exported at the feed-in rate. Charts show monthly production versus consumption and where each kWh went; the money view projects 25 years of electricity-price inflation and panel degradation into a cumulative cash-flow curve with the payback year marked, total lifetime savings and the effective return on the upfront cost.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- Production uses a seasonal irradiance model by latitude band, scaled by roof orientation and tilt — a south-facing 35° roof in central Europe yields roughly 1,000 kWh per kWp per year.
- Self-consumption is the economic key: a kWh used at home offsets the full retail price, while an exported kWh usually earns only the much lower feed-in rate — that gap is what a battery monetizes.
- Panels degrade about 0.5% per year and the payback curve includes it, along with your assumed electricity-price inflation.
- Local subsidies, net-metering rules and installation quotes vary widely — use real quotes for a final decision.
- Runs 100% in your browser — simulations are computed locally on your device.
- This is an educational estimate, not financial advice; talk to a qualified adviser before making money decisions.
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