Free Tool
Solar Panel Payback Calculator
Enter your system cost, size and region to see how quickly solar pays for itself, what you save each year, and the net benefit over 25 years.
Solar payback is your system cost divided by the money it saves each year on electricity. A typical UK home solar and battery system pays back in roughly 8 to 12 years, then keeps saving for the rest of its 25-year-plus life. Higher electricity prices and self-use shorten the payback.
Interactive Tool
Solar Payback Calculator
Estimated payback period
7.9 years
3,800 kWh generated per year at 950 kWh/kWp
Annual saving
£758
25 year net benefit
£11,626
Pairing panels with a battery lifts self-consumption sharply. Browse home battery systems
Estimates use typical UK regional yields and assume panel output degrades gradually over 25 years. Real savings vary with roof orientation, shading and how you use electricity.
How this is calculated
Annual generation is your system size in kWp multiplied by a typical yield for your region, from 950 kWh per kWp in southern England down to 800 kWh per kWp in Scotland. That generation is split into electricity you use yourself, valued at your import rate, and surplus exported to the grid, valued at your SEG rate.
Payback is simply the installed cost divided by the combined annual saving. The 25 year net benefit multiplies the annual saving over 25 years, applies a 7 percent allowance for gradual panel degradation, then subtracts the upfront cost. A home battery raises self-consumption because more of your generation is used at home instead of exported, so we bump the default from 45 to 70 percent.
Tariffs, SEG rates and installation prices change regularly, so treat these figures as a guide rather than a quote.
Frequently asked questions
How long is solar panel payback in the UK?
For most UK homes, around 8 to 12 years, depending on system cost, how much of the generation you use yourself, your electricity price and any export payments. After payback the savings are effectively free for the panels’ remaining life.
What affects the payback time most?
How much solar you use directly rather than export, your electricity unit price, the install cost, and adding a battery to store daytime generation for the evening. Using more of your own power is the single biggest lever.
Is home battery storage worth it?
A battery increases self-consumption by storing daytime solar for evening use, which can meaningfully cut bills, especially on a time-of-use tariff. It adds cost, so it pays back best for homes with higher evening usage.
Are there UK grants for solar and batteries?
Support changes over time and can include reduced VAT and specific schemes. See our guide on current UK solar and battery grants for what is available now before you budget.
