What the New UK Plug-In Solar Law Actually Says (Effective 27 August 2026)
- Hannah
- Jul 20
- 6 min read
The short version
The regulations were made on 16 July 2026 and come into force on 27 August 2026.
The instrument is SI 2026 No. 848, amending the Plugs and Sockets etc. (Safety) Regulations 1994 and the Electricity Safety, Quality and Continuity Regulations 2002.
It applies to solar devices with a maximum rated AC output of 800 watts or less.
Devices designed to store imported electricity are excluded from this route.
A compliant kit needs an approved plug and certification to the government's Interim Product Specification.
Before 27 August, the compliant route remains a fixed connection by a qualified electrician.
Most coverage of the UK plug-in solar changes has been written from press releases. We read the statutory instrument itself. This post sets out what the law actually does, what it deliberately leaves out, and the checks worth making before you buy a kit.
If you are looking for the broader picture of the UK's position, start with our guide on whether plug-in solar is legal in the UK. This post goes into the legal detail underneath it.
The instrument, in plain terms
The law is The Plugs and Sockets etc. (Safety) Regulations 1994 and Electricity Safety, Quality and Continuity Regulations 2002 (Amendment) Regulations 2026, SI 2026 No. 848. It was made on 16 July 2026, laid before Parliament on 17 July, and comes into force on 27 August 2026.
The obstacle it removes is narrower than most people assume. UK rules require plugs to conform to BS 1363, and BS 1363 does not permit a plug and socket to be used to connect electricity-generating equipment. That single restriction is why a perfectly safe solar kit could not be legally plugged in. The hardware was never the problem. The plug standard was.
The new regulations allow a notified body to approve a plug for a plug-in solar device even though it does not conform to BS 1363 in that one respect, provided it conforms in every other respect and the device meets the Plug-in Solar Device Interim Product Specification.
Alongside this, the electricity safety regulations now say a plug-in device must not be installed or operated unless it complies with that same specification. So the law opens a door and immediately sets the standard for walking through it.
What legally counts as a plug-in solar device
The regulations give a precise definition. A plug-in microgenerator must:
generate electricity directly from sunlight
have a maximum rated AC output not exceeding 800 watts
be intended for connection to a domestic installation by a standard plug and socket
operate in parallel with the distribution network
not be designed to import electricity for storage and later supply
Two of these are worth dwelling on.
The 800W is an AC limit, not a panel limit. It is measured at the microinverter output. This is why every credible UK kit is built around an inverter capped at 800W, and why panel wattage above that figure is not automatically a problem.
Storage is excluded. A device designed to draw power from your home to charge a battery for later use does not fall within this definition. Batteries are not banned, and battery systems remain perfectly legal, but they sit outside this particular plug-in route and need a conventional compliant installation. Anyone marketing a socket-connected battery bundle under these regulations has misread them.
What the law does not do
The regulations coming into force does not, by itself, put a legal kit in your hands on 27 August.
Products still need certifying. A kit is only compliant if its plug has been approved under the new route and the device meets the Interim Product Specification. Manufacturers and notified bodies are working through this now, so expect certified products to arrive in stages rather than all at once.
Grid notification still applies. Plug-in solar is grid-connected generation, so the G98 notification to your Distribution Network Operator remains. It is a form rather than a permission gate, but skipping it leaves you non-compliant.
Northern Ireland is partly different. The plug approval changes extend to England, Wales, Scotland and Northern Ireland. The electricity safety changes extend to England, Wales and Scotland only, so the Northern Ireland position is governed separately.
How to check a kit is actually compliant
From late August the market will fill quickly, and the gap between a certified product and a lookalike import will be invisible on a product photo. Before you buy, ask the seller four questions:
Does the device meet the Plug-in Solar Device Interim Product Specification?
Has its plug been approved under the new route by a notified body?
Is the microinverter output rated at 800W AC or below?
Is the inverter listed on the ENA type test register for G98?
A seller who cannot answer these clearly is selling you a compliance problem, not a bargain. This matters beyond legality: an uncertified generating device wired into your home is the sort of thing an insurer will take an interest in after a fault.
For reference, every Thunder kit is built around a microinverter capped at 800W AC and listed on the ENA type test register, and we handle the G98 notification for customers using our installation service. If you would rather not audit a spec sheet yourself, that is the shortcut.
What this means if you are buying
If you want to generate now, you do not need to wait. Compact solar on a balcony, fence or in a garden has always been legal in the UK when connected properly, via a fused spur on a dedicated radial circuit by a qualified electrician, with the DNO notified. That route was compliant before these regulations and remains compliant after them. It is how Thunder installs across the UK today.
If you specifically want to plug it in yourself, wait and be selective. The date is fixed, so there is no uncertainty left, only the wait for certified stock.
Do not pay a premium for the announcement. The hardware has not changed. A panel and an 800W microinverter are the same components they were in June. What changed is the paperwork around how they connect.
Where Thunder stands
Thunder Energy submitted a formal response to the DESNZ consultation behind these regulations, which drew 466 responses from across the industry.
Our position has been consistent since the March announcement. We build kits designed for socket connection, and in the meantime we install them compliantly so customers generate now rather than waiting on a timetable. The Storm range uses lightweight flexible panels for balconies, fences and walls, from £499.99. The Bolt range uses rigid panels built for gardens, sheds and flat roofs, from £549.99. Both are built around an 800W-capped microinverter, which is exactly the limit the regulations set. Free UK delivery on every kit, and professional installation across Greater London for £399.99, including the electrician and the DNO notification.
Frequently asked questions
When does plug-in solar become legal in the UK? 27 August 2026. The regulations were made on 16 July 2026 and laid before Parliament on 17 July, with commencement set for 27 August.
What is SI 2026/848? It is the statutory instrument that legalises plug-in solar in the UK. It amends the Plugs and Sockets etc. (Safety) Regulations 1994 and the Electricity Safety, Quality and Continuity Regulations 2002 to allow an approved plug to be used with a solar microgenerator of up to 800W AC.
Does the 800W limit apply to the panels or the inverter? The inverter. The regulations set a maximum rated AC output of 800 watts, which is measured at the microinverter rather than at the panels.
Can I plug in a solar battery system under the new rules? No. The regulations exclude devices designed to import electricity for storage and later supply. Battery systems remain legal but require a conventional compliant installation rather than this plug-in route.
Do I still need to notify my DNO after 27 August? Yes. Plug-in solar is grid-connected generation and the G98 notification still applies. It is a short form rather than an application for permission.
Will I need an electrician after 27 August? For a certified plug-in device, not for the connection itself. Many people might still choose professional installation for mounting, particularly with rigid panels or awkward sites, and some will prefer a permanent fixed connection.
How do I know if a kit is compliant? Ask whether the device meets the Plug-in Solar Device Interim Product Specification and whether its plug has been approved under the new route. If the seller cannot answer clearly, treat it as a red flag.
Can I install plug-in solar now instead of waiting? Yes. A fixed connection by a qualified electrician is compliant today and stays compliant afterwards, so a system installed now starts generating immediately.