In this guide
Short answer: an 800 W plug-in solar kit typically saves £60 to £130 a year in Great Britain at the October to December 2026 price cap of 26.32p per kWh. A south-facing, unshaded kit in southern England sits at the top of that range; a vertical one on an east or north-facing balcony in Scotland sits at the bottom. At roughly £300 to £600 for a compliant kit, payback is usually 3 to 8 years.
Savings by region and placement
Rough yearly figures for an 800 W kit (output capped at 800 W, panels around 800 to 900 Wp), using 75% of the output at home at 26.32p per kWh:
| Placement | South England | Midlands / Wales | North England / Scotland |
|---|---|---|---|
| South, tilted 30–40° | ~700 kWh / £138 | ~640 kWh / £126 | ~570 kWh / £113 |
| South, vertical on a railing | ~490 kWh / £97 | ~450 kWh / £89 | ~400 kWh / £79 |
| East or west, tilted | ~560 kWh / £111 | ~510 kWh / £101 | ~460 kWh / £91 |
| East or west, vertical | ~350 kWh / £69 | ~320 kWh / £63 | ~290 kWh / £57 |
These are our rounded estimates based on typical UK yields of about 850 to 1,000 kWh per kWp a year at the ideal angle; check your exact location free on the EU's PVGIS tool. The direction factors are explained in the best angle and direction.
Why the government says "up to £110"
GOV.UK's estimate assumes a good position and most of the output used at home. Two things pull real savings down: shade (railings, neighbouring balconies, trees) and low daytime use. If nobody is home in the day, a large share of the output goes to the grid for nothing. Two things push it up: a south-facing tilt and running the washing machine, dishwasher and tumble dryer while the sun is out.
Export: why it doesn't count
Smart Export Guarantee payments normally need an MCS-certified installation, and a plug-in kit is a DIY product, so in practice you won't be paid for exports at present. That makes self-use the whole game. The plug-in route also excludes batteries, so you can't store the surplus. See the UK rules.
Payback
| Kit price | £70 a year | £100 a year | £130 a year |
|---|---|---|---|
| £300 | 4.3 years | 3 years | 2.3 years |
| £450 | 6.4 years | 4.5 years | 3.5 years |
| £600 | 8.6 years | 6 years | 4.6 years |
The price cap changes every quarter. If unit rates rise, savings rise with them; on a cheaper fixed tariff they fall. If you're on a time-of-use tariff, value solar at your daytime rate.
Five ways to save more
- Face south and tilt if your balcony and building rules allow it.
- Avoid shade between about 10 am and 3 pm.
- Use delay timers on the washing machine and dishwasher to run at midday.
- Keep the kit at 800 W output: more panels help in winter, but above 960 Wp the specification recommends a professional wiring check.
- Buy a compliant kit at the lower end of the price range. See the buying checklist.
Frequently asked questions
How much does an 800 W plug-in solar kit save in the UK?
Roughly £60 to £130 a year. A well-placed kit makes about 450 to 650 kWh a year; if you use 70 to 85% of it at home at the October to December 2026 price cap of 26.32p per kWh, that's about £85 to £145 of electricity, less in the north or with shade. The government's estimate is up to £110.
How long does plug-in solar take to pay back in the UK?
At roughly £300 to £600 for a compliant kit and £70 to £130 a year in savings, payback is typically 3 to 8 years. Panels last 25 years or more.
Can I get paid for the electricity I export?
Generally not at present. Smart Export Guarantee payments normally need an MCS-certified installation, which a DIY plug-in kit doesn't have, so plan your savings on what you use yourself.
Does plug-in solar work in Scotland?
Yes, but it makes less: about 15 to 25% less than in southern England. Long summer days help; winter output is low.
Update log
- Guide published using the October to December 2026 price cap.
Sources and official texts