From 27 August 2025, plug-in solar panels that connect to a standard 13-amp socket will be legal in the UK. The change ends years of regulatory limbo that left thousands of households with unenforceable installations or outright bans from distribution network operators.
As reported by Engadget, the legalisation applies to pre-assembled kits that plug directly into a wall socket, generating up to 800W of power. The key change: these kits will no longer require professional installation or notification to the local distribution network operator (DNO), removing a major barrier for renters and flat dwellers.
Who qualifies, and who doesn’t
The new rules cover plug-in solar kits of up to 800W output, which connect via a standard plug and include an integrated inverter. That means any household with a suitable south-, east- or west-facing window or balcony can install one without an electrician. But there’s a catch: the kits must be certified to the new product standard (BS EN 50549-1:2025), and older uncertified units remain illegal. Ofgem confirmed the certification requirement in a technical note published on 12 June.
Renters are the biggest winners. Landlords cannot block a tenant from installing a certified plug-in solar kit, provided it does not damage the property or breach the tenancy agreement. The Energy Saving Trust estimates that 3.8 million UK households in flats or rented homes could now access solar generation for the first time.
What it costs a typical 3-bed semi
A typical 350W plug-in kit costs between £500 and £800, according to prices from major UK retailers. Connected to a south-facing window, it can generate roughly 260–300 kWh per year, about 20–25% of the electricity used by a standard 3-bed semi. At the current price cap of 24.5p/kWh (July 2025), that saves £63–£74 a year. The payback period is 7–11 years, assuming no major component failure.
But the savings are lower than a roof-mounted system. A full 4kW solar array costs £5,000–£7,000 but generates 3,500–4,000 kWh per year, with payback in 8–12 years and the added benefit of Smart Export Guarantee payments. Plug-in kits cannot export to the grid, so any excess power is lost. Ofgem figures show the typical export payment is 15p/kWh, adding £150–£200 a year for a roof system.
EPC impact, none, unless you upgrade
Plug-in solar panels will not improve your Energy Performance Certificate (EPC) rating. The EPC methodology treats any generation that is not permanently wired and registered with the DNO as zero-rated. That means no boost to your home’s EPC score, and no benefit if you’re trying to reach Band C for the 2030 minimum standard for rented homes.
However, the government’s new Home Energy Model, due in 2026, may change this. The Department for Energy Security and Net Zero confirmed in a consultation response that it is reviewing whether to credit plug-in generation in the next iteration of the Standard Assessment Procedure (SAP 2026). If adopted, plug-in solar could eventually contribute to EPC ratings, but not before 2027 at the earliest.
What to do now
If you’re a homeowner with a suitable roof, a full 4kW system remains more cost-effective over 20 years. But for renters, flat dwellers, or anyone who can’t install roof panels, the 27 August change is a genuine opportunity. Buy only a certified kit with the new BS EN standard mark, uncertified units will remain illegal and could invalidate your home insurance. Install before the end of September to capture the best autumn sun, and check your energy supplier’s terms: some may still require notification even if the regulator does not.
Frequently Asked Questions
No. Plug-in solar kits do not qualify for the Smart Export Guarantee because they cannot export power to the grid. Any electricity you don't use is lost. A full roof-mounted system with a proper inverter and DNO registration is required to receive export payments.
Possibly, if the kit is not certified to the new BS EN standard. Most insurers require any electrical generation equipment to meet UK safety standards. Always check with your insurer before installing, and buy only a kit with the new product certification mark.
