Solar savings calculator
See what solar panels, with or without a battery, would make and save on your roof. Built on town by town PVGIS data and today's energy prices.
Your solar savings
Pick your town and roof. We use PVGIS solar data for each town, the October to December 2026 price cap of 26.32p per kWh and 12p for exported power.
Estimated saving in year one in Birmingham£0
- Solar made per year0 kWh
- Off your bill£0
- Export payments£0
- Solar covers0%
- Our fixed price from£0
- Simple payback0 years
- Net gain over 25 years£0
Estimates at today's prices with no price rises, and without the extra you can make charging a battery on a cheap overnight tariff. Your survey gives exact figures for your roof.
Get my exact quoteHow the calculator works
The calculator multiplies your system size by the yearly output PVGIS gives for your town, adjusts for the direction your roof faces, then splits that power between what your home uses and what it exports.
South facing roofs get the full figure. East or west roofs are counted at 82% and north facing at 58%, in line with PVGIS runs at a 35 degree pitch. Your yearly electricity use is estimated from your monthly bill after taking off the standing charge. Without a battery we assume you use up to 30% of the solar directly; a battery raises that to 62 to 78%, capped by what your home actually uses.
Savings are valued at the price cap unit rate for power you no longer buy and at 12p for power you export. We do not add energy price rises, and we leave out the extra a battery can earn by charging on cheap overnight rates, so for most homes the real figure comes out higher. For the full picture read how long solar takes to pay back and the best tariffs for solar and batteries, or see our fixed prices.
Questions we get asked
Still unsure? Our advisers are real people who have stood on a lot of roofs.
020 3958 0158How accurate is the solar savings calculator?
It uses PVGIS output data for your town, the current price cap and a realistic share of solar used at home. Your roof pitch, shading and daily routine can move the result by 10 to 20% either way, which is what the free survey pins down.
Why does a battery increase the saving?
Without a battery a typical home uses about a third of its solar and exports the rest for 12p. A battery stores the afternoon surplus and uses it in the evening instead of buying power at over 26p.
What electricity price does the calculator use?
The Ofgem price cap for October to December 2026: 26.32p per kWh and 54.83p a day standing charge, and 12p per kWh for exported power on a flat export tariff.
Get a fixed price for your roof
Tell us a little about your home and we will send a guide price today, then book a free survey when it suits you.