BSI 2026 Plug-In Solar Tracker: BS 7671 A4, BS 1363, and the BSI Product Standard

At a glance: standards status

1. BS 1363-1:2023, UK 13A plugs and sockets

BS 1363 is the standard that defines the familiar UK 3-pin 13A plug and socket. The current edition is BS 1363-1:2023, and it governs the design, safety and testing of plugs, sockets and adaptors used in the UK.

For plug-in solar specifically, BS 7671 Amendment 4 (published 15 April 2026) carves a defined exception: a kit meeting the forthcoming BSI plug-in solar product standard may connect via a standard plug without a dedicated spur or an MCS-certified installer. For all other uses, BS 1363 continues to treat sockets as power outlets, not as inlets for externally generated power.

2. BS 7671:2018+A4:2026, the IET Wiring Regulations

BS 7671:2018+A4:2026 (the 18th Edition Amendment 4) was published on 15 April 2026 by the IET. It governs electrical installations in the UK, the wiring inside your walls, the protective devices in your consumer unit, and the rules an electrician follows when adding circuits.

Amendment 4 updates a range of rules across the wiring regulations and contains the regulatory change that opens UK plug-in solar. The key updates are in Section 712 (solar PV power supply systems) and Regulation 551.7 (low-voltage generating sets).

What Section 712 changed: it acknowledges that small-scale PV connected via a standard plug does not require a dedicated spur or an MCS-certified installer, provided the kit meets the forthcoming BSI plug-in solar product standard. Regulation 551.7.1 has been redrafted to address bidirectional energy flow on the supply side, and 551.7.2 requires generating sets to sit on the supply side of protective devices. The maximum per home is 800W AC peak.

What this means in practice: BS 7671 A4 has authorised the plug-in connection method for one defined class of equipment (BSI-certified plug-in solar kits at or below 800W AC) and only that class. The route exists in regulation. It cannot yet be used in practice because the BSI standard has not yet published and no certified product yet exists.

3. The BSI plug-in solar product standard, expected July 2026

BSI has indicated July 2026 for publication of a new product standard covering plug-in solar equipment. The document is a product specification: it sets out what a compliant plug-in solar product must do at the level of the kit itself, things like inverter behaviour, anti-islanding, connector type, labelling, safety testing.

What it changes:

• Manufacturers selling into the UK will have a clear specification to test against.
• Retailers will be able to verify a kit meets a UK-recognised product standard, rather than relying on European VDE marks.
• Electricians and DNOs will have a reference point when assessing equipment during a hardwired install.

What it does not by itself change:

• BS 7671 A4 has already authorised the plug-in route for BSI-certified kits. The BSI standard does not need to re-do that work.
• BS 1363 still governs sockets for general use. The carve-out for plug-in solar lives in BS 7671 A4, not in BS 1363.
• G98 notification still applies for the network side. Ofgem is consulting on a simplified G98 amendment for sub-800W type-tested equipment in Q3-Q4 2026, taking effect in 2027.

4. So what is compliant in the UK today, and after BSI publishes?

There are two routes to think about, separated by the BSI publication moment.

Compliant today (31 May 2026, before BSI publishes)

No certified plug-in solar kit yet exists in the UK, because the BSI standard has not yet published. So the only compliant install for buyers today is the hardwired route:

1. Buy a kit with a microinverter that is on the ENA G98 type-test register.
2. Engage a CPS-registered electrician (Competent Person Scheme: NICEIC, NAPIT, ELECSA, Stroma) to install a hardwired connection from the microinverter to a dedicated circuit on the consumer unit.
3. The electrician issues a Minor Works Certificate or EIC under BS 7671:2018+A4:2026.
4. The installer or the householder submits a G98 notification to the local DNO before energising. G98 covers single-phase installations up to 16A per phase.

Compliant after BSI publishes (expected July 2026)

Once the BSI standard publishes and the first kit is certified, an alternative route opens under BS 7671 A4 Section 712:

1. Buy a BSI-certified plug-in solar kit (800W AC max).
2. Connect via a standard plug to a compliant, RCD-protected socket on a sound circuit. No dedicated spur or MCS-certified installer required.
3. Submit G98 notification to the local DNO. Ofgem is consulting on a simplified flow for sub-800W type-tested equipment, expected to take effect in 2027.

Both routes are compliant. The hardwired route is still appropriate for any install where the building owner or installer prefers documented certification, or where the household wants a fixed isolator and labelling at the consumer unit.

5. Timeline of dated milestones

• 2023 BS 1363-1:2023 published

  Latest edition of the UK 13A plug, socket and adaptor standard. Continues to govern sockets for general use.

• May 2024 Germany passes Solarpaket I

  Germany lifts plug-in solar feed-in limit to 800W and authorises Schuko-plug connection. The UK reaches the same destination via a different chain in 2026.

• 2025 BSI announces work on plug-in solar product standard

  BSI begins the work programme for a UK product specification covering plug-in solar equipment.

• 15 March 2026 DESNZ written ministerial statement

  The Department for Energy Security and Net Zero issues a written ministerial statement confirming legalisation of plug-in solar in the UK.

• 24 March 2026 Public announcement on gov.uk

  UK Government publishes the formal commitment: "The government will work with the Energy Networks Association, DNOs and Ofgem to update the G98 distribution code and wiring regulations BS 7671 to allow UK households to connect <800W plug-in solar panels to domestic mains sockets, without the need for an electrician and with tailored safety standards." See gov.uk press release.

• 15 April 2026 BS 7671:2018+A4:2026 published

  IET and BSI officially publish Amendment 4. Section 712 acknowledges that small-scale PV connected via a standard plug does not require a dedicated spur or MCS-certified installer, provided the kit meets the forthcoming BSI plug-in solar product standard. Regulation 551.7 redrafted for bidirectional flow.

• 21 April 2026 £25m low-income pilot announced

  DESNZ announces a £25m pilot to put plug-in kits into low-income households, paired with the legalisation.

• 9 June 2026 Industry joint safety statement

  ECA, Electrical Safety First, the IET, NICEIC and SELECT issue a joint statement urging the Government to put product standards, enforcement, safe install routes, network notification and consumer guidance in place before plug-in solar is sold to consumers. Not a ban; a call to sequence the safety framework ahead of sale.

• July 2026 (expected) BSI plug-in solar product standard publishes

  Product specification for plug-in solar kits sold in the UK. Publication is the trigger that turns the BS 7671 A4 plug-in route into a practical buying option, because no kit can be certified until the standard exists.

• Q3-Q4 2026 Ofgem G98 amendment consultation

  Ofgem consults on a simplified G98 flow for sub-800W type-tested plug-in solar equipment. The amended G98 is expected to take effect in 2027.

• 2027 Amended G98 in force, Building Regulations updated

  The simplified G98 flow takes effect. Building Regulations are expected to be updated to reflect the practical install picture for plug-in solar.

6. The certification route, now confirmed in principle

For most of 2025 and early 2026, the question on this page was speculative: could the UK reach a plug-in route through product certification rather than rewriting BS 1363 from scratch? That question has been answered in principle.

The concern this route has to answer: a live plug during backfeed

The single biggest safety objection to plug-in solar via a socket has always been simple to state: if the kit is generating and someone pulls the plug, could the exposed pins be live and electrocute them? Any credible DIY route has to close that question completely. The trade view is that modern inverter electronics already can, and that a product standard is the right place to make that behaviour mandatory rather than optional.

eFIXX: We Tested Plug-In Solar. The Industry Got This Wrong. The safety bench tests start around the 5-minute mark.

What the video sharpens for this tracker. eFIXX measures the inverter shutdown at just over half a cycle of AC waveform, around 10 milliseconds, well inside G98's 0.5-second loss-of-mains envelope. They demonstrate that an older non-bidirectional RCBO still operates correctly under backfeed, which addresses the wiring-side concern raised against allowing generation through legacy protective devices. They also note the gap that the safety bodies have left unfilled, citing an 18-month investigation by Electrical Safety First with no published findings. The tracker view: the regulatory direction is now confirmed, the practical safety questions are largely answered by existing standards, and the BSI publication date is the remaining variable that decides when the route is usable for buyers.

A product certified for this purpose would have to demonstrate, as hard requirements:

• Rapid shutdown and automatic disconnect: the inverter de-energises its output within a fraction of a second if the connection is broken or the supply is abnormal.
• Anti-islanding: the inverter stops generating the instant the grid supply is lost, so it can never backfeed a dead network or an isolated circuit.
• No exposed live pins: the pins cannot be live once the plug is even slightly withdrawn, because the inverter senses the disconnection and shuts down first.
• Export limits and compliant voltage and frequency behaviour: the kit stays inside the envelope the grid expects and cannot push the local network out of tolerance.
• Safe operation on ring final circuits: the product is tested and rated for the real circuits found in UK homes.

If a product genuinely satisfies all of that, the live-pin scenario stops being a live risk. That is the engineering case behind the trade optimism.

What a DIY route would probably still require

Even on the optimistic reading, DIY would not mean no rules. The trade expectation is that a UK DIY route, if it arrives, would keep a fairly tight set of conditions:

• A maximum wattage limit, most likely in the 600W to 800W band.
• Certified inverters only, listed against the UK product standard.
• A compliant socket and circuit, possibly a dedicated or labelled socket rather than any socket in the house.
• DNO notification under G98 kept in place, even if simplified.
• A prohibition on adaptors and extension-lead chains.
• RCD protection on the circuit the kit connects to.

So the realistic version of DIY plug-in solar is closer to "buy a certified kit, connect it to a known-good socket, register it, follow the rules on the label" than to "plug anything into anything".

The honest summary, updated: the Government confirmation (DESNZ 15 March 2026), the mechanism (BS 7671 A4 Section 712 for BSI-certified kits) and the regulatory date (A4 published 15 April 2026) are all in place. What is left is the BSI standard publishing on or close to its expected July 2026 date, and the first kit being certified to it. The page is updated the moment either of those moves.

7. What I will and will not say about timing

The page has shifted position with the regulatory moves. As of 31 May 2026 the phrasings below are accurate and will not be wrong in six months. I will still avoid the lazy "plug-in solar is legal now" framing without the BSI-certification caveat, because without it the line is misleading: no certified product yet exists, so a buyer cannot today install under the plug-in route.

If you are writing a piece on plug-in solar in 2026 and want phrasings that will not be wrong in six months, you can borrow any of these:

• "DESNZ confirmed the legalisation of plug-in solar in a written ministerial statement on 15 March 2026."
• "BS 7671 Amendment 4, published 15 April 2026, authorises plug-in solar via a standard plug for kits meeting the forthcoming BSI plug-in solar product standard."
• "The BSI plug-in solar product standard is expected to publish in July 2026 and is what makes the plug-in route practically usable."
• "Until BSI publishes and the first product is certified, no certified plug-in solar kit yet exists, so the compliant install for buyers today is still a CPS-registered electrician with a hardwired connection plus G98 notification."
• "Maximum per home under BS 7671 A4 is 800W AC peak."

8. Primary sources

• IET press release, 15 April 2026: Amendment 4:2026 officially published
• IET Wiring Matters: The impact of Amendment 4:2026 on the 18th Edition
• EAL: BS 7671 Amendment 4 (2026) key changes explained
• NICEIC: Understanding BS 7671:2018 + Amendment 4:2026
• BSI: BS 1363-1:2023, specification for 13A plugs, socket-outlets and adaptors
• IET: BS 7671 Wiring Regulations (18th Edition) Amendment 4:2026 product page
• BSI: standards programme and announcements (plug-in solar product standard)
• Energy Networks Association: ENA EREC G98 (small generator connection)
• UK Government press release, 24 March 2026: "Government to make plug-in solar available within months"
• ITV News, 24 March 2026: Government to make plug-in solar available within months (DESNZ ministerial statement coverage)
• UK Government press releases (search archive)

If a source above moves or is updated, this page will be updated within 7 days. Corrections and challenges are welcome at [email protected].

9. Frequently asked questions

• Will the BSI 2026 plug-in solar standard make it legal to plug a solar kit into a UK 13A wall socket?
  The legalisation has already happened in principle. BS 7671 Amendment 4, published 15 April 2026, updated Section 712 to authorise plug-in solar via a standard plug for kits meeting the forthcoming BSI plug-in solar product standard. The standard is expected to publish in July 2026. Until it publishes and the first certified product is listed, no kit can yet be sold as BSI-certified, so the plug-in route cannot be used in practice. Until then the install for buyers today defaults to a CPS-registered electrician with a hardwired connection plus G98 notification.
• What did BS 7671:2018+A4:2026 actually change?
  Amendment 4 to BS 7671:2018 was published on 15 April 2026 by the IET and BSI. It updates Section 712 to acknowledge that small-scale PV connected via a standard plug does not require a dedicated spur or an MCS-certified installer, provided the kit meets the forthcoming BSI plug-in solar product standard. Regulation 551.7.1 is redrafted for bidirectional energy flow and 551.7.2 requires generating sets on the supply side of protective devices. Maximum per home is 800W AC peak.
• Is plug-in solar legal in the UK in 2026?
  As of 31 May 2026, the UK Government has legalised plug-in solar via the DESNZ written ministerial statement of 15 March 2026 (announced publicly on 24 March 2026). BS 7671 Amendment 4, published 15 April 2026, authorises the plug-in connection method for kits meeting the forthcoming BSI plug-in solar product standard (expected July 2026). Until the BSI standard publishes and certified kits list, no buyer can yet install under the plug-in route; the compliant install today is still a hardwired connection by a CPS-registered electrician plus G98 notification.
• When does the BSI plug-in solar standard publish?
  BSI has indicated July 2026 for publication of the plug-in solar product standard. This page is updated when BSI confirms the document number and publication date.
• What is the compliant install route for plug-in solar in the UK today?
  No certified plug-in solar kit yet exists, because the BSI plug-in solar product standard has not yet published. Until it does, the compliant install route is a CPS-registered (Competent Person Scheme) electrician completing a hardwired connection from the microinverter to a dedicated circuit on the consumer unit, then submitting G98 notification to the DNO before energising. Once BSI publishes and the first kit is certified, the plug-in route under BS 7671 A4 Section 712 also becomes available.
• Is the UK following Germany's Solarpaket I model?
  Yes, broadly. Germany's Solarpaket I (May 2024) authorised the Schuko plug for plug-in solar via primary legislation. The UK has reached the same end point through a different document chain: DESNZ ministerial statement (15 March 2026), BS 7671 A4 Section 712 update (15 April 2026), and the BSI plug-in solar product standard (expected July 2026). The UK approach defines a certified-product route at the equipment level rather than declaring sockets bidirectional in primary law, but the practical outcome for buyers is similar once the BSI standard publishes.
• Where can I track changes to this page?
  The "Last reviewed" date in the author box and the "Updated" badge in the header reflect the most recent fact check. Substantive corrections are logged on the site changelog. If you are a journalist or electrician and want to be notified when this page changes, email me at [email protected].

Related reading: From Schuko to BSI: Germany's path and the UK route ahead · BS 7671 and Plug-In Solar in the UK · Complete UK Guide to Plug-In Solar · G98 / DNO Notification Guide · Renter Guide · FAQ