Do solar panels really pay for themselves?
Yes, most UK solar systems really do pay for themselves, typically in 6 to 10 years. The payback comes from the grid electricity you stop buying (around 27p per kWh) plus Smart Export Guarantee income (around 15p per kWh). After payback, the system keeps generating largely free electricity for the remaining 15 or more years of its life.
The payback maths
Payback is the installed cost divided by the annual benefit. A £7,000 system saving £900 a year pays back in about 8 years. Because panels last 25 to 30 years, the bulk of the system's life is spent generating free electricity after it has broken even. Rising electricity prices shorten the payback further.
What affects whether it pays
- Roof direction and shading (south, unshaded is best).
- How much electricity you use during daylight.
- Whether you add a battery to lift self-use.
- Your electricity unit rate.
Frequently asked questions
- What is the average solar payback in the UK?
- Around 6 to 10 years for a well-sited system, then largely free electricity for the rest of its 25-year-plus life.
- Can solar fail to pay for itself?
- It is unlikely with a suitable roof, but a north-only or heavily shaded roof, or very low usage, can extend payback significantly.
Related questions
Indicative estimates based on UK average data. Last updated 27 May 2026.