Is plug-in solar actually worth the money?
The short answer
For some households, clearly yes. For others, honestly no.
A kit costs £336 to £999 and saves roughly £60 to £150 a year. Payback runs from about three years for a cheap kit in a sunny spot with someone home, to well over ten for an expensive one in a poor spot. Which end you land on depends almost entirely on whether anyone is home during the day.
We do not sell kits and we are not paid by anyone who does, so here is the plain arithmetic, including the cases where the answer is no.
Four households, four answers
Same kit in each case: two panels totalling about 930W, £449, on a tilted frame facing south. The difference is the house.
| Household | Kit makes | Used at home | Saves a year | Pays back in |
|---|---|---|---|---|
| Retired couple, Plymouth, home most days | 1,043 kWh | 50% | £137 | 3.3 years |
| Family, Birmingham, someone in and out | 900 kWh | 40% | £95 | 4.7 years |
| Two commuters, Glasgow, house empty 8 to 6 | 793 kWh | 30% | £63 | 7.2 years |
| Flat, Manchester, panels flat on a north-facing wall | about 330 kWh | 40% | £35 | 13 years |
Worked from PVGIS 5.3 yields (European Commission Joint Research Centre, queried 26 September 2026) at 26.32p per kWh, the Ofgem price cap for 1 October to 31 December 2026. The north-facing figure is an illustration, not a PVGIS query. Your own numbers: use the calculator.
The first two households are getting a good deal by any measure. The third is borderline. The fourth should not buy one.
When the answer is no
- You have nowhere sunny to put it. A north-facing wall, a shaded yard or a balcony that gets two hours of light will not pay. Before you buy anything, watch the spot across a whole day.
- The house is empty every weekday and you cannot shift your washing. Without a battery and without an export tariff, most of what the kit makes just leaves.
- You are moving soon. Most kits can be unbolted and taken with you, but check yours before you assume it. A payback of five years is no use if you are gone in two and the frame is bolted down.
- You are renting and your landlord has not agreed. See renters and landlords before you spend anything.
- You were hoping to be paid for the surplus. With one narrow exception, you will not be.
When the answer is yes
- Somebody is usually home in the day. Retired, working from home, small children, shift work. This is the single biggest factor.
- You have a sunny south-facing spot you can tilt a frame in. A garden, a flat roof, a south balcony rail.
- You are in the south or east. Brighton makes 43 per cent more than Inverness from the same kit.
- You can move your heavy use to the middle of the day. Dishwasher, washing machine, immersion heater, car charger if you have one.
- You would otherwise pay for a full rooftop system. A plug-in kit is a tenth of the cost and needs no scaffolding, no installer and no roof survey.
What kits actually cost
On 26 September 2026 the kits we could find on sale to UK households ran from £336 to £999. Broadly:
- One panel, 340W to 515W: £449 to £679. Makes about half what a two-panel kit does. Worth it if space is tight.
- Two panels, 800W to 1,260W: £336 to £999, a much wider spread. Usually better value per unit generated, because one inverter serves both panels.
- Ground-mounted units with a heavy frame: the upper end. You are paying for engineering that does not blow over.
Watch for delivery charges, which can be substantial on something that weighs 45kg and is nearly two metres long. Some sellers include it, some add £50 or more. Our kit tracker lists every compliant kit with the price range we saw and the date we saw it.
The things that are not about money
Plenty of people buy one and never work out the payback, which is fine. A kit is the cheapest way to find out whether solar suits your house before committing to a roof full of it. It keeps the fridge and the router running on your own electricity. It is something you can set up in an afternoon and understand completely, which is not true of much else in a modern home.
Just do not buy one expecting it to noticeably dent a winter bill. In December a 930W kit in Leeds makes around 30 units across the whole month. In July it makes around 108. The saving is real, but it arrives in the summer.
Questions people ask
How long do the panels last?
Panels themselves typically carry a 25 or 30 year performance warranty and degrade slowly. The microinverter is the part most likely to need replacing first. Check what warranty comes with the kit, and who honours it.
Does it work in winter, or in cloud?
Yes, just less. Panels produce on overcast days, typically 10 to 25 per cent of what they would in full sun. Cold does not hurt them: they are slightly more efficient when cold. Short days are the problem, not temperature.
Would a battery fix the empty-house problem?
It would, and that is exactly why people want one. But battery-integrated plug-in devices are outside the current rules, and no compliant kit on the register includes one. See batteries and plug-in solar.
Will it put my house insurance up?
Tell your insurer, in writing, before you buy. We have not found a UK insurer that publishes a policy on plug-in solar specifically, so do not rely on anyone’s guess, including ours. Ask yours directly and keep the reply.
Can I add a second kit to double the saving?
Not at present. The grid rules allow one device per household. If you want more than 800W, you are into a conventional installed system with an electrician and a formal connection application.