Solar + battery calculator

See whether solar panels make financial sense for your home, and compare which Smart Export Guarantee tariff pays you most for exported electricity.

Verified: 26 April 2026 from PVGIS regional irradiance data

How is this calculated?

System size (kWp)Typical UK domestic: 3-5 kWp. Larger homes 5-10 kWpRegionYour DNO region affects irradianceRoof orientationThe direction your panels faceRoof tilt (degrees)UK optimum is ~35°. Flat roof = 0°Annual electricity usage (kWh)Find on your annual statement. UK average ~3,500 kWhCurrent electricity unit rate (p/kWh)Default is current price cap. Check your bill if different

Include a home battery

Total install cost (£)Quote total for panels, inverter, install, scaffolding, plus battery if applicable