Yearly saving£758
Payback10 years
Profit over 25 years£10,252
Your region
Worked out for UK average at today's electricity price of 26.32p per kWh. Typical 4.5 kW system costing £7,600.
The short answer
For most UK homes with a suitable, unshaded roof, yes. Solar panels usually pay for themselves in around 9 to 12 years, according to Utilita, and keep working for 25 years or more.
How the numbers work for a typical home
| Step | Typical figure |
|---|---|
| System size | 4.5 kW (about 10 to 11 panels) |
| Cost to install | about £7,600 (Energy Saving Trust estimate) |
| Electricity made each year | 4,275 kWh |
| Used in your home (about 40%) | 1,710 kWh, saving £450 |
| Sent to the grid (the rest) | 2,565 kWh, earning £308 at 12p |
| Total saving each year | £758 |
| Payback time | 10 years |
These are estimates. Your own savings depend on your roof, how much electricity you use in the day, your export rate and future energy prices.
What makes them worth it
- A south, east or west-facing roof without shade from trees or buildings.
- Using electricity in the day. Every unit you use yourself saves you the full electricity price, about 26.32p today. Every unit you export earns much less.
- A good export rate. 12p to 16p per kWh is available from many suppliers. See the best export rates.
- Staying in your home long enough to get your money back.
When they might not be worth it
- A heavily shaded or north-facing roof.
- A roof that will need replacing soon. Do the roof first.
- If you plan to move within a few years. Panels may add value to a home, but you won't see the savings yourself.
Don't forget
- The inverter (the box that converts the electricity) usually needs replacing once during the panels' life, which adds to the cost.
- Panels lose a little output each year. Our 25-year figure assumes about 0.5% a year.
- Until 31 March 2027, there's no VAT on solar panels.
Work out your own figures with the solar payback calculator.
Sources: Energy Saving Trust figures via Which?, Utilita, OpusFlow, Reonic regional yield table, SunSave export tariff list (updated 16 September 2026), Octopus Energy tariff data.