Enter a few details about your home and current energy use to get an instant estimate of your annual savings, payback period, and 25-year total — based on real UK sunshine data and 2026 electricity prices.
Use our solar panel cost calculator to estimate upfront pricing for your home.
This calculator gives a realistic estimate based on the same factors UK installers use when sizing a system: your roof's orientation, regional sunshine hours, your current electricity usage, and whether you're storing excess generation in a battery rather than exporting it.
These figures are an estimate to help you plan — your MCS-certified installer will provide an exact quote based on a survey of your actual roof, shading, and consumption profile.
| System size | Typical annual generation | Estimated annual saving |
|---|---|---|
| 3.5kW (small terrace/flat) | ~2,800 kWh | £350 – £550 |
| 4.5kW (typical semi) | ~3,800 kWh | £500 – £750 |
| 5.5kW (typical detached) | ~4,600 kWh | £650 – £950 |
| 6.5kW+ (large detached) | ~5,500 kWh | £800 – £1,150 |
Figures assume average UK sunshine hours, a mostly south-facing roof, and 2026 electricity unit rates. Households with a battery typically land at the higher end of each range; east/west-facing roofs typically land lower.
Most UK households save between £400 and £1,100 a year on electricity bills after installing solar panels, depending on system size, roof orientation, and how much electricity they use during daylight hours.
Savings are based on the size of the solar system, average UK sunshine hours for your region, the proportion of generated electricity you use directly versus export, and your current electricity unit rate.
Yes. Without a battery you typically use 40-50% of generated electricity directly and export the rest under the Smart Export Guarantee, though savings are higher with a battery as more self-generated power is used at home rather than exported at a lower rate.
Typical payback periods in the UK range from 9 to 14 years, depending on system cost, household usage patterns, and electricity prices. Panels generally continue producing for 25 years or more, so most of that period is pure savings after payback.