Solar PV Calculator – Solar Panel Yield by City
Hour-by-hour solar simulation with 5 years of real weather data: yield, self-consumption, battery and payback – validated against PVGIS.
Hour-by-hour simulation with real weather data
All results are simulations based on historical weather data (PVGIS, EU Joint Research Centre) and established models. Local shading, snow, module-specific properties and future weather can cause deviations. This is no substitute for a professional on-site assessment.
The weather service is currently unreachable – the results are based on a clear-sky climate estimate and are less accurate.
Total peak power of all modules (kWp). A typical module today has 400–450 Wp.
Direction the modules face. Drag the handle on the compass or pick a preset. The coloured lines show the path of the sun at your location on the solstices and the equinox.
Angle between module and horizontal. 0° = flat, 90° = façade. Typical pitched roofs: 30–45°.
Determines how well the modules are cooled. Free-standing modules stay coolest; in-roof modules get hottest and lose more yield.
Cables, inverter, soiling and mismatch. 14 % is the PVGIS default; modern systems often reach 10–12 %.
Average yield loss caused by trees, chimneys or neighbouring buildings.
Maximum AC output. If it is lower than the module power, peaks are clipped. 0 = no limit.
Share of light that the surroundings reflect onto the modules (albedo). Matters mostly for steep modules.
Annual electricity consumption without heat pump and electric car. Simulated with the BDEW H0 standard load profile.
Annual electricity consumption of a heat pump. Distributed according to the actual hourly outdoor temperatures at your location.
Usable capacity. Simulated with 90 % round-trip efficiency, 0.5 C power and standby consumption.
Enter your consumption on the left to see self-consumption and autarky.
Insurance, maintenance, metering, inverter reserve – in % of the investment per year.
Simplified model without financing, taxes or subsidies. The feed-in tariff is assumed to be constant.
Exact position of the sun: NOAA solar position algorithm, evaluated six times per hour.
Irradiance on the module: Perez anisotropic sky model (1990) for diffuse light plus direct beam and ground reflection – the standard in professional planning tools.
Reflection losses: Martin & Ruiz angle-of-incidence model: at shallow angles the module glass reflects more light.
Module temperature & efficiency: Faiman temperature model and Huld efficiency model for crystalline silicon – the same as in PVGIS of the EU Joint Research Centre.
System & inverter: system losses, shading and inverter limit are applied in every hour.
Consumption & storage: BDEW H0 standard load profile with the realistic day-to-day and within-hour fluctuations of a single household (calibrated against HTW Berlin), heat pump driven by the actual hourly temperatures, EV charging and battery (90 % round-trip efficiency) simulated hour by hour.
Validated against PVGIS
We compared our model with PVGIS 5.3, the reference tool of the EU Joint Research Centre – on exactly the same hours (2019–2023), 1 kWp, 35° tilt (Sydney 30°), facing the equator, 14 % losses.
Annual yield in kWh/kWp. The small, consistent difference comes from the sky model: we use the Perez model for diffuse light, PVGIS the simpler Muneer model.