Free, instant estimate based on your postcode. Real solar data from the EU Photovoltaic Geographical Information System.
No signup required · Takes 60 seconds
We find your location and look up solar irradiance data for your area.
Tell us about your home, roof, and energy usage for a tailored estimate.
See your recommended system, payback period, and 25-year savings projection.
For a 3-bed semi-detached in the South East
Our calculations use real solar irradiance data from the EU's PVGIS system, which is based on satellite measurements. Financial assumptions use current Ofgem tariff rates. Actual results may vary based on specific roof conditions and shading.
Most domestic solar installations fall under permitted development and don't need planning permission. Exceptions include listed buildings, conservation areas, and some flat roof installations. Always check with your local authority.
A battery increases self-consumption from ~40% to ~75%, meaning you use more of the solar energy you generate instead of exporting it cheaply. Our tool shows you the difference so you can decide.
The SEG requires energy suppliers to pay you for excess electricity you export to the grid. Rates vary — we use 15p/kWh (Octopus Energy rate) as a reasonable estimate.