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Plug-in solar

Solar panels that plug into a socket

A small kit on a patio, wall, fence or flat roof that feeds your home through an ordinary outdoor socket. No roof work and no installer, for a few hundred pounds. It won’t run your home, but it can cover the power your home uses all day long.

What it is

A plug-in kit has one or two solar panels, a small inverter that turns their power into mains electricity, a mounting frame and a special plug. You put the panels somewhere sunny and plug the cable into a socket. Whatever your home is using at that moment comes from the panels first, so you buy less from the grid.

Kits like these have been popular in Germany for years as “balcony solar”. They became legal in England, Scotland and Wales on 27 August 2026.

Why it pays: your base load

Even when nobody is home, a house keeps using electricity: the fridge and freezer, the broadband router, alarms, chargers and everything on standby. In most homes that adds up to somewhere between 80 and 200 watts, all day and all night.

A plug-in kit is sized to cover that steady load through the daylight hours. Because almost everything it makes is used straight away, you don’t need an export payment for it to save money. Running the washing machine or dishwasher in the day uses even more of it.

The rules in Great Britain

  • 800 VA into the socket, at most. The kit’s inverter can’t put more than 800 VA (about 800 watts) into your wiring. The panels themselves can be bigger, up to 2,000 W, which helps on dull days.
  • A complete, approved kit. Buy a whole kit listed on the Energy Networks Association (ENA) Type Test Register. A loose inverter and panels bought separately don’t count.
  • One kit per home, straight into a wall socket. No extension leads, adaptors or linking kits together. Outdoor sockets must be weatherproof.
  • Tell your network operator. You must let your local Distribution Network Operator know when you connect it, and when you remove it.
  • No battery. A plug-in kit can’t be used with a battery.
  • Where it can’t go. Not on timber balconies, timber or plastic cladding, or a wall you share with a neighbour. Fixings must be removable, and cable ties or straps alone are not enough.
  • Renting or leasehold? Ask your landlord or freeholder first.
  • Northern Ireland has its own rules, and plug-in kits are not yet allowed there.

From the Department for Energy Security and Net Zero’s Plug-in Solar Device Interim Product Specification (version 2.0, July 2026) and Energy Saving Trust guidance. Checked 12 November 2026.

Calculator

What would a kit save you?

These are estimates, not financial advice.

We are not qualified or regulated financial advisers. The calculator works from the figures you enter and from assumptions that may not hold: energy prices, interest rates and panel output all change. Speak to a regulated financial adviser before borrowing or moving savings.

Where it goes
How it is mounted
–

The direction the front of the panels faces, from 0° (north) round through 90° (east), 180° (south) and 270° (west). A phone compass app will tell you.

Shade during the day
Your home
–

Fridge-freezer about 40 W on average, router 10 W, standby and chargers 30 to 60 W. Most homes are 80 to 200 W. Your smart meter display shows it late at night, when little else is on.

p per kWh

26.32p under the price cap (1 October to 31 December 2026).

Is someone at home in the day?
p per kWh

Usually nothing: export tariffs normally need an MCS certificate.

% a year
years

Panels last 25 years or more. Microinverters are usually warranted for 10 to 15.

What else the money could do
–

Before inflation. Top easy-access accounts pay about 4.5 to 5%.

–

An assumption, before inflation. Investments can fall as well as rise.

% a year

Used to show every result in today’s money.

% APR

Credit card, overdraft or car finance. Leave empty if none.

Paying with a loan or card

–saved in year one
–to pay for itself
–estimated yearly return after inflation
–net gain over 15 years, in today’s money
The kit

Recommended for you

–

Ranked by yearly return on your figures. Jump with the buttons above, or step through the ranking with the arrows.

Pick from the full list or type in your own kit

W

The panels’ combined rating. 2,000 W is the legal maximum.

VA

What it can put into the socket. 800 VA is the legal limit.

£

Including delivery, and any ballast or fixings you need to buy.

Through the year

Covering your base load

The dashed line is what your home is using. Green is solar used as it is made; amber is spare power that goes back to the grid. If the panels could make more than the inverter’s rating, the curve is cut flat at that level: that is the 800 VA limit at work.

Yearly rate after inflation, side by side

Each rate has 3% a year general inflation taken off. The kit’s figure is the yearly rate that would turn its price into the same stream of bill savings. A loan or debt rate is what you pay, not what you earn.

What you would have after 15 years, in today’s money

The kit itself is counted as worth nothing at the end, which is cautious.

What this suggests

    Running position, year by year

    Pounds ahead or behind compared with doing nothing, in today’s money.

    Approved kits

    Plug-in kits you can buy now

    Every kit here is on the ENA Type Test Register, and none puts more than 800 VA into the socket. We rank them all by the same rules, whatever the brand or seller: the estimated yearly return on your own figures from the calculator, or the cost of each kWh the kit makes over its life. Bigger panels make more on dull days, but the most any kit can deliver at one moment is 800 VA. Compare that cost with the 26.32p you pay for a kWh from the grid.

    #KitPanels and inverterPriceEstimated a yearCost per kWhReturn for youWhere to buy

    Before you buy, search the kit’s make and model on the ENA Type Test Register yourself, as listings change. Check what the price includes: some kits need ballast weights or fixings for your surface.

    Good to know

    Will it keep the lights on in a power cut?

    No. By law the inverter switches off within a fraction of a second when the grid goes down, to protect people working on the lines. For power-cut protection you need a battery system with automatic switchover or a portable power station. See power-cut protection.

    Can I add a battery later?

    Not to a plug-in kit. The rules don’t allow one. If you want storage, a properly installed system is the way to go: try the ROI calculator.

    Does it need planning permission?

    Usually not for a small kit in a garden or on a house wall, but listed buildings, conservation areas and flats can be different. Check with your council if you are unsure.

    How much will it make?

    An 800 W kit facing south on a tilted frame makes roughly 600 to 750 kWh a year in most of Britain. Upright on a wall or fence it makes roughly a quarter less, though it does better in winter when the sun is low.

    Is it safe?

    Approved kits are tested to switch off as soon as they are unplugged, so the pins of the plug are not live. Your home needs RCD protection on the socket circuit. If your fuse box is old or uses rewireable fuses, have an electrician check it first.

    Is it worth it compared with rooftop solar?

    Rooftop solar saves far more each year but costs thousands. Plug-in solar suits renters, flats with a garden or wall, and anyone who wants a low-cost start. Compare both in the ROI calculator.

    Not sure which is right for you?

    Tell us where the panels would go and what you want to run, and we’ll point you in a sensible direction.

    Ask us a question Rooftop solar calculator