Guernsey property · Energy & the home
Solar potential in Guernsey
Digimap and the States of Guernsey provide a free rooftop solar suitability map. It models solar exposure across roof surfaces so you can begin exploring a home’s potential.
The map opens on the provider’s website in a new tab. Our guide and property navigation stay here. We do not send a property’s address or coordinates to the map.
What the map tells you
Digimap describes a surface model containing buildings, trees and other structures. It accounts for roof direction and pitch, terrain and surrounding shadows, seasonal sun angles, and direct and diffuse sunlight. The colours represent modelled incoming solar energy, not measured panel electricity production.
Open the map, locate the correct building and read its current legend. Compare individual roof surfaces rather than treating one colour as a rating for the whole property.
What it cannot confirm
The model includes shading from the trees and structures represented in its surface data. It cannot establish roof strength, electrical connection capacity, future vegetation growth or installation details. Check present-day conditions on site and ask for a professional solar design survey.
It cannot confirm roof condition, ownership, installation costs, permissions, grid connection or savings for your household.
From an interesting roof to an informed decision
- Confirm the building. Check that the mapped roof is the one you mean, especially in terraces, shared buildings and properties with outbuildings. If it is absent or unclear, ask the map provider or an installer.
- Check access and roof rights. Establish ownership or consent arrangements, roof condition and any planned repairs. A flat or tenancy does not automatically include the right to install panels.
- Ask for a site-specific survey. Discuss shade, usable roof area, orientation, structure, panel layout and maintenance access. Do not translate map colours straight into an electricity-output promise.
- Verify permissions and connection requirements. Check with the relevant planning authority and electricity provider before committing. Map inclusion or exclusion is not a permission decision. Guernsey planning information and official sources.
- Compare written proposals. Ask installers to state system size, estimated annual generation, losses, assumptions, warranties and all installation costs. Savings depend on your usage, tariffs and export arrangements; a battery changes the calculation.
Buying a home with panels?
Ask the seller for ownership or lease details, installation records, warranties and recorded generation. Keep existing panel performance separate from a model of what an empty roof might support.
A map, not a property score
This guide concerns the Guernsey map. Do not assume it covers Alderney, Sark or the other islands of the Bailiwick.
We have not assigned solar scores or generated per-property energy or savings estimates. A survey is the appropriate next step when a roof looks promising.
Seasonal context · 2001–2020
How sunlight changes through the year
At our representative Guernsey model point, average daily solar energy on a horizontal surface ranges from 0.70 kWh/m² in DEC to 6.04 kWh/m² in JUN. These NASA POWER regional averages are solar energy arriving at the surface, not electricity generated by panels.
PVGIS is the European Commission’s separate modelling tool. Choose your own location, system size, slope, direction and losses. We do not send property addresses to it or calculate a quote.
Sources and dates
Map provider: Digimap and the States of Guernsey. How Digimap made the Guernsey rooftop solar map (opens in a new tab).
Guide sources reviewed . This is our review date, not the date of the map’s imagery or model. Check the provider’s latest information for coverage and updates. This independent guide does not imply provider endorsement. We link to the map; we do not reproduce its imagery or data.