Property-specific solar estimate
Solar roof calculator for UK homes
Check an exact UK property for solar panels, compare Google’s roof model with a PVGIS generation estimate, then test savings and payback using your own electricity use and tariff.
Step 1
Find the exact property
Choose a full address so the roof model is matched to the building, not the centre of its postcode.
Your address is sent to Google to locate the property. Energy Review does not save it or include it in analytics.
How to use the two estimates
A close match is useful reassurance. A wide gap is a reason to ask an installer which roof areas, losses and shading are included in their proposal. Use your own tariff rates and quote for the financial result.
Before signing an installation contract
Ask for a site survey, an itemised generation estimate, the assumed shading and system losses, equipment warranties, and evidence that the installer and products meet any requirements attached to your chosen export tariff. You can also use our seven-day solar forecast after the system is installed.
If you do not want to select an address, use our quicker solar panel cost and payback calculator. It estimates costs, savings and export earnings from the system details you enter rather than a building model.
Questions about the estimate
How accurate is this solar roof calculator?
Where available, the calculator uses Google Solar roof geometry and shading-aware panel layouts, then lets you run the same roof segments through PVGIS. Both are estimates and neither replaces an installer survey, structural assessment or quotation.
What happens when detailed roof data is unavailable?
The calculator keeps the selected property coordinates and switches to a manual system description. PVGIS then estimates generation for the location, system size, roof pitch and direction you provide.
Does Energy Review store my address?
No. The address is used during the calculation to obtain property coordinates and is not saved by Energy Review or included in analytics events. Google processes the address lookup under its own terms and privacy policy.
Why can Google Solar and PVGIS show different figures?
They use different information about the roof, weather and shading. A large gap is worth discussing with your installer rather than averaging the two results.
What makes a roof suitable for solar panels?
Usable roof area, direction, pitch, shading and the roof structure all matter. This calculator can model area, direction, pitch and some nearby shading where detailed data exists, but an installer still needs to assess condition, access and structural suitability on site.
Written by
Rob Gibbs
Hi, I'm Rob, and I run Energy-Review.co.uk. I initially started this project in 2018 when I was looking to switch energy suppliers and found there wasn't a website that provided simple, data-backed reviews on all the suppliers available. Since then, I have spent a lot of time (too much, some may say!) looking at all publicly available data about each supplier and writing reviews using this information. These reviews are updated as regularly as possible, and any data is backed up by a source where necessary. I have also started writing guides on various energy-related topics, which hopefully you will find useful. If you find any issues, please use our contact form to let us know.