CoverMapCost and payback by system size
| Property size | System size | Total cost (incl. battery) | Typical payback |
|---|---|---|---|
| 1 bedroom | 1.5kW | £4,850 | 13.7 years |
| 2 bedrooms | 3kW | £7,500 | 10.6 years |
| 3 bedrooms | 4.5kW | £9,800 | 10.4 years |
| 4+ bedrooms | 6kW | £13,000 | 11.0 years |
Why location changes the numbers
A 3kW system in Greater London can pay back in around 9.9 years, while the same system in Scotland can take around 11.3 years — the gap comes down to fewer sunlight hours and different regional electricity rates, not the panels themselves.
Is a battery worth adding?
A battery lets you store daytime solar generation for use in the evening, rather than exporting unused power back to the grid at a lower rate than you pay to import it. It adds to the upfront cost and extends payback slightly, but usually increases the proportion of your own electricity use you cover from solar.
Frequently Asked Questions
Do I still need the grid if I have solar panels?
Yes — UK solar systems (without very large, expensive battery setups) don't fully replace grid electricity, especially in winter with fewer daylight hours. Solar reduces your grid usage and bill rather than eliminating it entirely for most households.
Do solar panels add value to a UK home?
Evidence suggests they can be a modest positive for resale value, particularly as buyers increasingly factor in running costs, though it's rarely a pound-for-pound return on the installation cost — the main financial case is long-term energy bill savings rather than resale value.