Calculate Your Site's Solar Potential
⚡
Section 1 — Electricity Costs
What type of electricity tariff do you have?
Flat Rate
One unit rate applies at all times of day
Day and Night Rate
Different rates during the day and overnight (e.g. Economy 7, time-of-use)
p/kWh
Please enter your unit rate.
📐
Section 2 — Roof Area
🗺️ Satellite map: To enable address search and roof drawing, add your Google Maps API key to this file — see the setup instructions in the HTML comments at the top. Without a key, simply enter your roof area in m² using the field below. A rough estimate is fine at this stage.
Click once per corner to trace your roof outline. Double-click to close the shape and calculate the area.
Click once per corner to trace your roof outline. Double-click to close the shape and calculate the area.
Satellite view not active
Add your Google Maps API key (see top of file) to enable satellite imagery and roof drawing.
Until then, enter your roof area manually below.
Until then, enter your roof area manually below.
or enter area manually:
m²
Based on your roof area and consumption data
—
kWp
Estimated system capacity
—
kWh / year
Estimated annual generation
—
£ / year
Estimated electricity savings
—
tCO₂e / year
Estimated carbon offset
Assumptions
Indicative estimate only. This tool uses fixed assumptions and your stated tariff and consumption data. Actual generation and savings will depend on factors like shading, roof condition and panel layout. Orientation and tilt adjustments are applied in a detailed desktop feasibility study. The carbon offset figure uses the UK grid emission factor of 0.177 kgCO₂e/kWh (DESNZ 2024). For this estimate, we have used a specific annual yield of 950 kWh/kWp.