From August 27, plug-in solar panels become legal in Great Britain under Statutory Instrument 2026/848. The change opens the technology to millions of households, including renters and flat owners who could never access rooftop solar. For brokers and risk managers, the legalisation creates a category of unmanaged electrical risk now entering the residential property book at scale.
The fire risk attached to solar installations is already documented. QBE Insurance research, using Freedom of Information requests to 49 UK fire services, found solar panel fires rose 133% between 2022 and 2025, more than double the 52% growth in installations over the same period. UK fire services attended 212 solar fires in 2025, with DC cabling faults and faulty connections accounting for 49 incidents.
Conventional rooftop systems involved MCS-accredited contractors. Plug-in systems are self-installed and exempt from mandatory electrician sign-off, so installation quality is harder to verify and will not appear in any MCS certificate.
The sharpest exposure sits in leasehold residential buildings. Plug-in solar panels connect directly to a property's electrical circuit. In a leasehold flat, that circuit shares infrastructure with the wider building.
A poorly connected system, fitted to outdated wiring or mounted on a combustible balcony surface, can push electrical fault risk into communal parts of the building. The freeholder or managing agent may not know it is there. The Property Institute has warned that installation in blocks of flats raises considerations around building safety, fire risk and leaseholder permissions. Each application, it said, should be assessed individually against the specific characteristics of the building and the terms of the lease.
Germany legalised an equivalent system earlier, and incident records show the output cap matters. A 2024 fire in Germany involved a plug-in solar array paired with a lithium battery. The affected system was operating above the permitted 800W output cap. The same limit applies under UK regulations from today.
The UK framework does not require an electrician for standard plug-in solar installation. A G98 notification to the local Distribution Network Operator is required before connection, but this is an administrative step, rather than an inspection. Battery storage is also explicitly excluded from the plug-in framework. Any system connected to a battery unit falls outside the approved category and should be treated separately for underwriting purposes.
“Plug-in solar panels promise cheaper, greener energy, but they shouldn’t be treated like a plug-and-play gadget," said Megan Dunford, head of large and complex property claims at Zurich UK. "Fundamentally, you’re adding a mini power station on your home, so you need to go into it with your eyes open.
“The big difference is, these systems feed electricity directly into your home’s electrical network and, if wiring is outdated, poorly maintained or unsuitable, there is a risk of electrical faults, overheating and potentially fire."
Plug-in solar installations can now appear on insured risks with no notification trigger or inspection requirement attached.
The relevant question for brokers placing block-of-flats and landlord policies is whether standard policy wording and lease terms address self-installed electrical equipment. The Property Institute has advised managing agents to establish a clear consent process before residents make purchases. Brokers handling block-of-flats cover should confirm whether lease terms and policy wording account for plug-in solar before the first renewal cycle following August 27.
