Plug-in solar kits are having a moment. They're cheap, easy to install, and promise to slash household bills. But several UK industry groups - including the Electrical Contractors' Association, Electrical Safety First, the Institution of Engineering and Technology, and certification bodies NICEIC and SELECT - have issued a joint warning about the technology, flagging six safety concerns that suggest the road to cheap solar may be paved with good intentions and questionable wiring.
Let's start with the basics: plug-in solar connects panels to a microinverter that converts DC power to AC and feeds it into a home via a regular wall outlet. No storage, modest output, but hey, it might keep your router running. The first problem? Power flowing both ways can mess with Residual Current Devices (RCDs) - the safety switches that cut power when they sense a leak. The groups cite one death in Australia linked to such a failure, though Australian regulators from other states beg to differ.
Then there's the fire risk. Over half of UK housing is more than a century old, meaning wiring that's seen better decades. Plugging in multiple solar units could cause localized overheating, especially in cables that are already tired. The groups also worry about cheap products flooding the market - like kits with flattened cables designed to slip under doors, which might seem clever to a DIYer but would make any qualified electrician reach for a drink.
Network operators can't monitor or manage power from these units, potentially affecting grid stability. And if the grid goes down, microinverters might not shut off fast enough, backfeeding power when it's not wanted. Then there's the liability headache: how will insurers react to damage from self-installed hardware? Landlords, leaseholders, and insurers are left in a gray area.
Finally, consumers being consumers: extension leads, adapters, and general cheapness could create trip hazards from badly routed cables, or worse, solar panels on balconies falling off into busy streets. "A poorly regulated bargain product may reduce bills in the short-term, but it can also transfer risk onto households, emergency services, insurers, network operators and, ultimately, government," the groups warn, adding that a "rushed rollout could potentially weaken confidence in the energy transition."
Others in the industry point out that solar panels introduce combustible materials, ignition sources, and extra weight to balconies and high-rise buildings. The UK has some of the toughest electrical standards globally, so these concerns aren't just navel-gazing. And given the flood of dodgy chargers and power banks online, plug-in solar seems poised to join the ranks of products that are cheap, convenient, and slightly terrifying.
If you live in an old house, have overheating wiring, bought your kit from a sketchy retailer, or suspect your installation skills are subpar, maybe call an electrician. Your wallet might save a few quid, but your home's electrical system shouldn't have to pay the price.