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Plug-in solar in the UK: what the rules actually say

The rules changed very recently, a lot of pages about them were written in a hurry, and several of the ones ranking today attribute rules to the wrong document. Everything below is quoted from the legislation and the government specification themselves.

Plug-in solar became lawful in Great Britain on 27 August 2026, when two statutory instruments came into force. A device is only compliant if it meets the government's product specification, which the legislation refers to directly — so the specification is a legal requirement, not advice. Sources and the date we read them are at the bottom of this page.

What the legislation itself says

The Plugs and Sockets etc. (Safety) Regulations 1994 and Electricity Safety, Quality and Continuity Regulations 2002 (Amendment) Regulations 2026 (SI 2026/848) was made on 16 July 2026, laid before Parliament on 17 July 2026, and came into force on 27 August 2026.

It contains one number that matters to a buyer. A plug-in microgenerator is defined as one that “has a maximum rated alternating current output not exceeding 800 watts” (regulations 2(3) and 3(2)).

Everything else about the product is not in the instrument. It is in thePlug-in Solar Device Interim Product Specification, which the instrument names and therefore incorporates.

What the product specification requires

From version 2.0 of the specification, July 2026 — the government's own page marks an earlier version “[Withdrawn]”, so check you are reading the current one:

  • “maximum apparent power not exceeding 800 VA”, at “up to 253 V (AC)” and 50 Hz (Scope, §1)
  • “maximum current does not exceed 3.5 A” (§4.1)
  • “the maximum permissible sum of PV module DC power output … is 2000 W” (§4.1) — the panel side may be larger than the 800 VA the inverter is allowed to deliver
  • “No more than two PV modules shall be connected in series”, with open-circuit voltage at the inverter inputs not exceeding 120 V DC (§4.2.2)
  • The inverter “shall automatically disconnect from the mains supply within 100 ms”, and the voltage at accessible plug pins must fall “below 34 V within 100 ms” (§6.2.3.3.3)

Why a European balcony kit is not automatically legal here

This is the part that is easy to get wrong if you have been reading German Balkonkraftwerk pages, and it is a hardware difference, not a paperwork one.

The specification requires the device to be connected “solely by the manufacturer-supplied standard plug” (Scope, §1), and that plug must be “designed to BS 1363-1”, must “incorporate partially insulated pins to prevent access to live conductive parts”, and must be a “non-rewireable moulded plug fitted with a BS 1362 fuse not exceeding 5A” (§6.2.3.2). A German kit ships with a Schuko or Wieland connector and does not meet this.

There is also a registration requirement on the manufacturer, and it gives you a check you can actually perform: manufacturers “shall register devices on the ENA Type Test Register (ENA Direct Connect platform) and obtain confirmation that the device has been assessed and identified as compliant prior to placing them on the market” (§7). If a product is not on that register, its compliance is not something a seller's description can establish for you.

One device per household — and where that rule actually comes from

Several pages currently state that the statutory instrument limits you to one device. It does not. The specification says “Only one plug-in solar product shall be used per household final ring circuit” (Scope, §1), and explains where the limit originates: network requirements, specifically “Engineering Recommendation G98 Issue 2 Amendment 1 2026”, which “restrict this to one device per household”.

The distinction is not pedantry. A rule that lives in an engineering recommendation can be revised by the body that publishes it, on a different timetable from the legislation — so “the law says one” and “the current network rules say one” will not necessarily stay the same statement.

Notifying your distribution network operator is separately mandatory; the specification requires manufacturers to tell you so, and to say how (§8.2.3.1).

Planning permission, and a trap for balconies specifically

The Town and Country Planning (General Permitted Development) (England) (Amendment) Order 2026 (SI 2026/896) was made on 29 July 2026 and came into force on the same day as the safety regulations. It brings plug-in solar into permitted development — with an exclusion that matters if you are reading this because you have a balcony.

Permitted development does not apply “in the case of plug-in solar, where any part of the plug-in solar would be installed on a wooden wall, balcony or enclosure” (article 3), nor on “a wooden fence, gate, wall or other means of enclosure” (article 4). A timber balcony is a common thing to want to hang panels on, and it is precisely the case the Order carves out.

Note the territory. This Order “extends to England and Wales” and amends the England permitted development order; the safety regulations are the Great Britain instrument. “The UK” is doing a lot of work in most articles on this subject — Scotland and Northern Ireland have their own planning regimes, and this page does not cover them.

What this page deliberately does not tell you

It names no product, quotes no price and estimates no saving. stromFit's calculators model a household hour by hour against a verified catalogue of systems, and both the catalogue and the load model are German. Producing a British payback figure from them would mean presenting a German answer in pounds.

If you want to see the method in the meantime, thepayback calculator and themethodology are both in English — they are about the German market, and they say so.

Sources

Every quotation above was read in the primary document on 30 August 2026, not taken from another article.

This is a summary of published rules, not legal advice, and it is accurate as of the date above rather than as of the date you are reading it.