Plug-in solar testing shows safe use with standard circuits

The government has confirmed that ‘plug-in’ solar will not require the upgrade of conventional consumer units, and is safe for standard mains plugs, following safety testing that found no significant issues with the technology.

It has launched a consultation seeking industry views on enforcing the rules so consumers can safely install plug-in panels in their homes.

The announcement comes alongside backing for the technology from major retailers at a government-led roundtable. Bosses from Currys, B&Q, Asda, Amazon, Lidl, Screwfix and Wickes – representing four thousand stores and significant online presence -, discussed the ‘crucial role of plug-in solar in the clean energy revolution’ with Minister for Energy Consumers Martin McCluskey.

Minister McCluskey said:

Plug-in panels can be transformative for renters or those on lower incomes, so I welcome the conversation today with household names such as B&Q and Currys showing a huge amount of support for getting the panels in people’s homes. This easy-to-install tech can cut people’s bills and help make the UK less reliant on global fossil fuel markets.”

The concept of the panels is that they can be put on balconies or in any outdoor space and used directly through a standard mains socket, without an installation cost. Last year saw a record 269,000 solar installations completed in the UK – 37% higher than the year before. Around 255,000 of these were rooftop solar.

Graham Bell, CEO of B&Q, said:

We welcome the introduction of plug-in solar panels to the UK market, which will help households to generate their own energy and reduce their bills. This builds on our existing range of portable solar and battery solutions. We are working closely with government and suppliers to understand and help shape the guidance, ensuring any products we offer are safe, compliant and straightforward to install. We look forward to making plug-in solar available to our customers as soon as possible.”

The consultation proposes changes to the Plugs and Sockets etc. (Safety) Regulations 1994 (PSSR), so as to allow consumers to connect plug-in solar systems (without batteries) directly to a standard mains socket, provided products meet defined safety requirements.

Alongside the necessary regulatory changes, DESNZ said that it is also proposing an interim product specification to ensure that only safe and compliant products can be placed on the UK market during a transitional period, while enduring standards are developed.

The safety testing programme examined thermal behaviour; protective device interaction; anti-islanding response; reverse power flow; export limitation; voltage and frequency response; start-up and shutdown behaviour; and electromagnetic compatibility across a range of circuits – including aged sockets, mixed domestic loading, extension leads, and degraded contact conditions.

The authors concluded:

The evidence indicates that plug-in PV systems can demonstrate safe and technically coherent behaviour within the tested no-modification boundary. Across key safety test scenarios, devices maintained stable operation, protective devices continued to function, anti-islanding disconnection occurred within required limits, and no sustained unsafe energisation was observed following protective device operation. Thermal behaviour remained acceptable under representative operating and high temperature conditions. No electrical hazard was identified as a result of socket connected plug-in PV operating within the tested export envelope. Reverse-current testing did not identify localised thermal hotspots or evidence of disproportionate conductor loading at the tested maximum export levels.”

However, the study noted that product quality is not uniform across the market and so a UK-specific product specification would be recommended.