The Mismatch Between the Rules and the Shelves
The legalisation taking effect on 27 August 2026 is built around a deliberately simple product: one or two solar panels, a grid-following microinverter, a fused UK plug. The Interim Product Specification excludes plug-in battery systems and battery-integrated solar devices in terms — the government's consultation response restates it plainly, and says battery products “raise additional technical and regulatory considerations which have not been assessed as part of this work.”
Now look at what the UK market actually sells. The premium kits that dominate listings — the EcoFlow STREAM series, Zendure SolarFlow, Anker's Solix Solarbank line, the Jackery Navi 2000 — are all built around integrated battery storage. That is their selling point: store your midday generation, use it in the evening. The products best known to UK buyers are precisely the products the new plug-in route excludes.
This was not an oversight. It was the single most contested aspect of the consultation — the government acknowledges the exclusion of battery storage was among the most frequently raised issues, with respondents arguing batteries increase self-consumption and improve the economics. The government's answer: not yet, not in this framework, evidence-gathering continues. There is no timeline for bringing batteries in.
What This Means in Practice
- From 27 August, the DIY plug-in route is panels-only. A compliant kit — once verified on the register; our certification tracker follows that — can be plugged in by anyone. No battery version of that exists, legally.
- Battery kits are not banned. An EcoFlow STREAM or Zendure SolarFlow remains perfectly legal to buy and use — but as a conventionally installed system, wired in by a qualified electrician with a G98 notification, exactly as before. The new rules neither help nor hinder that route.
- Mixing is where people will get caught out. Expect marketplace listings that pair a compliant-looking panel kit with a plug-in battery, or battery kits marketed with “legal from August” framing. Both are wrong. If it stores energy and plugs in, it is outside the specification.
So Which Should You Buy?
It depends on what you are optimising for. The honest comparison:
Panels-only plug-in kit (the new route). Cheapest entry point, zero installation cost, renter-friendly, and legal to self-install from 27 August once verified kits exist. The catch: without storage, you only bank savings on electricity you use while the sun is shining. For a typical flat with daytime appliance use, a well-sited 800W kit still pays its way — our self-consumption guide covers how to maximise it, and the savings calculator will give you realistic numbers.
Battery-integrated system (the old route). Stores the midday peak for evening use, so a much higher share of generation offsets your bill — but you are paying for the battery, plus an electrician to install it properly, and the simplicity advantage disappears. Our battery storage guide works through when the battery premium actually pays back.
The uncomfortable truth for manufacturers is that the UK has just legalised the product category they have been moving away from. Expect a wave of panels-plus-microinverter UK kits — stripped-down versions of the German market's standard offer — while the battery question waits for the enduring standard. If the government follows Germany's trajectory, batteries will come; Germany took years to get there too.
Weighing panels-only against a battery system?
Run your own numbers — self-consumption is the variable that decides it.