Is plug-in solar legal in the UK?

Plug-in solar: a small panel array with a built-in inverter that plugs into an ordinary socket, sold across Europe for years as Balkonkraftwerk: was not lawful to connect in Great Britain until 27 August 2026.

SI 2026/848 was made on 16 July 2026 and came into force on 27 August 2026. The change is real. It is also narrower and more specific than most of the coverage suggests, and the gap between “plug-in solar is now legal” and “this kit is legal” is where people are going to lose money.

The four conditions

1. 800 VA, and 3.5 A

The specification sets a maximum apparent power of 800 VA supplied to the mains installation, and a maximum current of 3.5 A. Nearly everything written about this says “800W”; the real figure is 800 VA of apparent power, measured at the inverter output.

The distinction matters less for shopping than for understanding what the inverter must be rated at, but if a seller quotes a figure above 800 VA, that is disqualifying.

2. You may fit up to 2,000 W of panels

This allows the panels to exceed the inverter rating while export remains capped.

The specification caps PV module DC power output at 2,000 W, against an 800 VA AC output. So a compliant kit can carry substantially more panel capacity than its inverter can deliver at once, and in UK conditions that is a better design, not a compromise. Panels rarely reach their rated output here, so an oversized array lifts generation through the dull, diffuse light that dominates the British year, while the inverter simply clips on the few brightest days.

If a seller tells you the panels must total under 800 W, they have misread the rule.

3. Solar only: batteries are out of scope

The specification says plainly that it does not apply to, among other things, “plug-in battery systems” and “plug-in solar PV devices integrated with battery systems”.

It goes further: instructions must carry a prominent warning that the device is not intended to be connected to, operated with, or used in conjunction with a battery energy storage system.

That rules out a meaningful share of what is most visible in UK retail: the all-in-one units pairing a small array with a few kWh of storage. Legalising plug-in solar did not legalise those.

4. It must be on the ENA Type Test Register

Check the public register before buying.

Manufacturers must type test the device to G98 requirements, register it on the ENA Type Test Register (through the ENA Direct Connect platform), and obtain confirmation that it has been assessed as compliant before placing it on the market. The specification adds that a device merely submitted for registration is not thereby compliant.

Plus: notify your network operator

Legalisation did not remove the obligation. G98 notification to your distribution network operator is required, and the specification requires the product to carry a statement that notification about connection and disconnection is mandatory.

How to notify, and who to notify: about ten minutes, free, and no approval to wait for.

One device per household, for now

Here the specification and the grid code differ, and the stricter one wins:

• The product specification permits one plug-in solar product per household final ring circuit, so that current through the connection to the consumer unit stays within safe levels.
• G98 Issue 2 Amendment 1 2026 currently restricts this to one device per household, and that applies unless and until G98 is amended.

So: one, today. The specification anticipates that changing, but “expected to change” is not a basis for connecting a second one.

What you are buying

An 800 VA kit in a reasonable position generates in the region of 650 to 800 kWh a year, and only the part you consume as it is generated is worth anything to you, because plug-in kits are not metered for export.

That is not nothing. It is also not solar in the sense most people mean: a conventional 4kWp roof array produces 3,400 to 4,200 kWh a year, roughly five times as much.

What to check before you pay

• The device is listed on the ENA Type Test Register. Ask, and check.
• Inverter output is 800 VA or less, maximum current 3.5 A.
• The kit contains no battery, and is not designed to work with one.
• Total PV module DC output is 2,000 W or less: more panels than inverter is fine, and good.
• Your consumer unit has RCBO protection and is in good condition.
• The mounting is rated for the surface and for wind loading at the height you intend.
• You know which network operator covers your postcode, and you notify them.

Where this sits in the market

There is a reasonable argument that plug-in solar matters more as a signal than as a technology: it is the first time Great Britain has allowed anyone to generate their own electricity without an installer, a survey and a five-figure contract. For renters and flat-dwellers: a third of UK households, and a group every other page on this subject quietly ignores: it is the only option that has ever existed.

If you own a suitable roof, compare it with plug-in against a real installation, and the numbers are not close.