Plug-in solar panels have gone on sale across England, Scotland and Wales, allowing households to generate electricity from sunlight without the cost or complexity of installing conventional rooftop solar.

The easy-to-install systems can generate up to 800 watts of electricity, enough to provide as much as 20% of an average home’s electricity use. At peak output, the government says a typical system could power appliances including a fridge, television, Wi-Fi router, laptop, phone charger and Xbox Series S simultaneously.

Households could save up to £110 a year on their electricity bills, according to government estimates. The panels can be placed in outdoor spaces and, in some cases, on balconies, with no installation cost.

The regulatory changes follow independent safety testing of the technology’s key electrical components. The government says the UK’s safety requirements are more stringent than those in Germany, where plug-in solar is already widely used, with around half a million new devices installed there last year.

Major retailers including Currys, B&Q, Screwfix, Amazon, Argos and Wickes are expected to stock the systems online and in stores.

However, consumers have been urged to check whether they need permission before installing a panel. Requirements could include consent from a landlord, freeholder or building owner, as well as planning permission or listed-building consent.

Only one plug-in solar device is currently permitted per home, although that device can contain multiple panels. Connecting separate systems together – ‘daisy chaining’ – is not currently allowed, although the government is considering changes that could permit multiple devices in future.

The panels generate direct-current electricity from sunlight, which a microinverter converts into alternating current before it is fed through a standard household socket. Electricity is drawn from the grid when demand exceeds solar generation, while surplus power can be exported automatically.

Trevor Hutchings, CEO of the Renewable Energy Association said: ‘From today, with little more than a trip to the shops, people in Britain will be able to harness the energy of the sun to power their households.

‘The arrival of plug-in solar is a huge step forward in democratising renewable energy and giving everyone the access they deserve to clean, cheap, homegrown power. Plug-in solar saves money – up to £100 a year – and it’s only right that this benefit should be felt by renters and flat-owners as well.

‘Our electricity prices are some of the highest because of our exposure to volatile international gas markets.  Innovations like plug-in solar and the wider renewables roll out will help us bring down bills and strengthen our energy sovereignty.’

Northern Ireland is not yet included in the rollout and may follow once its regulations are updated.