Your community energy group has money to spend and a neighbourhood full of roofs.
Roofs and streets from OpenStreetMap; energy numbers from the Solar Potential app; funding modelled on GB Energy's Community Fund. Every assumption is shown in the game.
The frame is the area that becomes your neighbourhood: about 480 × 360 m. Buildings, roads and trees come from OpenStreetMap. UK only.
Worked example
This is the site on its own, with nothing else installed. In play, a community battery or the substation limit can change the figures. Every number comes from the same model as the game; the assumptions are listed under “The numbers behind the game”.
Solar Street is a prototype game about community energy. You play a community energy group with money from a share offer and a GB Energy grant, and a real neighbourhood of Hinckley, Leicestershire, built from OpenStreetMap. Choose which roofs, car parks and homes to put solar on, keep within the substation's limit, and run the year to see what the plan earns and gives back to the community.
A supermarket roof on its own, as the game works it out.
One of each kind of site in the Queens Park and St Peter's area, on its own, best payback first.
solar-app): panel capacity 0.2 kWp per m², 0.85 system losses, 60% usable flat roof, 0.233 kg CO₂ saved per kWh. It uses the Google Solar API for real roofs.Installed costs per kWp, the community tariff (18p), grid price (25p) and export price (12p), running costs, battery and plug-in kit prices, the substation upgrade and community battery, members' interest (4%) and repayment (20 years), school term dates and holiday use, and the demand of shops, schools and other buildings are the game's own estimates of typical 2026 figures. They are listed under “The numbers behind the game”. Check them against local quotes before relying on them.
Map data © OpenStreetMap contributors (ODbL). Map display by Leaflet. Built on the code of the Minefield remake. A prototype: not affiliated with GB Energy, the Midlands Net Zero Hub or any community energy group.
Neighbourhood 1
Year one
Solar generated each month against what the neighbourhood used. Summer surplus is sold to the grid, or wasted if the substation can't take it.
Click a roof, car park or field to see how much sun it gets, what panels would cost and how quickly they would pay back. Then fit panels, and batteries where they help.
Turn on the sun map (S) to colour every roof by how much sun it gets: yellow is best, purple is poor. A red sign means the owner or the council has said no.
Buildings buy the solar power they use from your group at the community tariff, cheaper than their supplier. Power they can't use is exported to the grid for less. Batteries shift daytime power into the evening, so more of it is sold locally.
The substation can only export so much. On a sunny summer afternoon, anything over the limit is wasted. A community battery soaks up the peak; an upgrade raises the limit.
When you're ready, run the year to see your plan play out, and earn up to three stars. You can always come back and improve it.
Drag to move around, scroll or pinch to zoom. Keys: S sun map, R run the year, Esc menu, arrows to pan, + and − to zoom.
Generation uses the Solar Potential app's formula: panel capacity is 0.2 kWp per m² of usable roof, and a year's output is capacity × sunshine hours × 0.85 for system losses. The CO₂ saving is 0.233 kg per kWh, also from the app. Everything else is a typical UK figure for 2026, listed here so you can judge it.