Is Plug-In Solar Worth It in the UK?

The government's impact assessment estimates that 800W of panels with little shade make about 690 kWh a year facing south at a 30° tilt, and about 378 kWh hung upright facing east or west. Its central case sits in between, at about 534 kWh.

You only save money on the power you use as it's made, because you probably won't be paid for the rest (more on that below). The government assumes a home with average use (3,323 kWh a year) and someone in on weekday daytimes uses 62% of the south-facing kit's power (428 kWh) and 72% of the upright kit's power (272 kWh).

So the south-facing kit replaces about 13% of the electricity an average home buys. That's a useful trim, not a replacement for your bill. Most of it comes between spring and autumn, so it does little for winter heating.

At 26.32p per kWh, with nothing paid for spare power, here is what the government's three examples work out at with a £500 kit, the government's central kit price.

South-facing, tilted at 30°: about £113 a year, paying back in about 4.4 years. Somewhere in between: about £92 a year, about 5.4 years. Upright on a balcony facing east or west: about £72 a year, about 7.0 years.

If you need an electrician to fit an outdoor socket (the government's model uses £200), payback stretches to about 6.2 years for the south-facing kit and about 9.8 years for the upright one. The government also allows £150 if you pay for help mounting the panels.

Over the government's 15-year appraisal period, with a £100 replacement inverter after 10 years, a south-facing £500 kit comes out about £1,090 ahead at today's rate, and an upright balcony kit about £474 ahead. These are simple figures that assume today's electricity price for the whole period.

The government says kits are likely to cost around £400 to £600 at first. Change the kit price, your spot and your rate in the plug-in solar calculator.

It suits you if you have an unshaded south-facing garden, flat roof or balcony, someone is at home in the day, and you can run things like the washing machine or dishwasher while the sun is out. The more of the power you use as it is made, the bigger the saving.

It suits you less if your only spot is shaded or faces north, or the home is empty all day. In those cases you will use less of what the panels make, so your saving will be lower than the figures above.

Check before you buy if you rent, own a leasehold flat or live in a managed building: you need permission first. Flats, buildings with cladding and timber balconies can have extra fire safety rules, and you may need planning permission or listed building consent. The Energy Saving Trust says plug-in solar is not yet permitted in Northern Ireland.

Yes, in England, Scotland and Wales. The law that allowed it is SI 2026/848, and a kit must meet the government's Plug-in Solar Device Interim Product Specification (version 2). The main limits are below.

The kit can feed no more than 800W into your home. The panels themselves can add up to 2,000W, with the inverter capping the output. If the panels add up to more than 960W, the specification says to think about having an electrician check your wiring first.

It must plug straight into a fixed wall socket with its own plug. Extension leads, multi-way adaptors, travel adaptors and RCD adaptors are not allowed. The Energy Saving Trust says to use a socket on a circuit with no lights or wired-in appliances such as a boiler or cooker, and only one plug-in solar kit per home for now.

You must register the kit so your electricity network operator knows it is there, and tell them if you remove it. The rules cover solar only: plug-in batteries are not part of them.

Probably not at first. Export payments under the Smart Export Guarantee normally need a certified installation and a meter that records exports, and the government expects that this will not apply to many plug-in solar owners to begin with. That is why every figure on this page counts spare power at 0p. If you do get an export rate, the saving goes up.

Pick the sunniest, least shaded spot you have, and tilt the panels towards the south if you can. Then shift flexible jobs into the middle of the day: the washing machine, dishwasher or charging.

An energy monitor plug shows what each appliance really uses, so you can see what the panels could cover. Use it on appliances only: the solar kit itself must go straight into the wall socket. To see what individual appliances cost to run, try the appliance running cost calculator.

If payback looks too slow for your home, cheaper steps can cut your bill sooner. Our draught-proofing savings calculator shows how fast sealing gaps pays back.

Generation, home-use shares and costs come from the DESNZ plug-in solar final-stage impact assessment (July 2026). The rules come from SI 2026/848, the DESNZ Interim Product Specification v2 and the Energy Saving Trust's plug-in solar checklist. The electricity rate is the Ofgem price cap average Direct Debit unit rate for England, Scotland and Wales, 26.32p per kWh for 1 October to 31 December 2026. All checked on 7 October 2026. The full source list, with links, is on our plug-in solar calculator page.

This is general information, not electrical, legal or financial advice.