The law says you must tell your network operator before you switch a plug-in solar kit on, or at the time you do, not within 28 days afterwards. The wording is in regulation 22(2)(c) of the Electricity Safety, Quality and Continuity Regulations 2002, and there is no 28 day period anywhere in that regulation.
You would not know that from most of what is online. On 28 September 2026 an AI answer engine told us, flatly, that you “must notify your local DNO within 28 days under G98 regulations” and “can start using your panels straight away”. In the same session it said notification is mandatory “before you connect”. It was carrying both versions of the answer at once, and none of the pages it cited was the law.
The exact wording of the law
The duty to notify is not in the new plug-in solar regulations themselves. We checked: SI 2026 No. 848, which made plug-in solar legal from 27 August 2026, contains no notification wording. The duty sits in an older set of rules, the Electricity Safety, Quality and Continuity Regulations 2002, usually shortened to ESQCR, at regulation 22.
Regulation 22(2) applies to small sources of electricity connected in parallel with the network: in short, ones that do not exceed 16 amps per phase and that switch themselves off if the network supply is lost. A compliant 800W plug-in kit is well inside that. For those sources, paragraph (c) requires that:
“the person installing the source of energy ensures that the distributor is advised of the intention to use the source of energy in parallel with the network before, or at the time of, commissioning the source.”
Electricity Safety, Quality and Continuity Regulations 2002, regulation 22(2)(c), as amended, read on legislation.gov.uk on 26 and 27 September and 7 October 2026
Three phrases matter:
- “the person installing”: with a plug-in kit there is no installer, so in practice that is normally you.
- “the distributor”: the network operator, the company that owns the cables in your area. Not your energy supplier.
- “before, or at the time of, commissioning”: commissioning means switching it on for the first time. So the latest you can leave it is the day you plug it in.
Regulation 22 is marked as extending to England, Wales and Scotland. It does not cover Northern Ireland, where the plug-in rules do not apply either.
So where does 28 days come from?
Not from nowhere. Network operators have long published guidance for small solar systems fitted by an installer, where the installer tells the operator about the connection after the work is finished. Much of that guidance gives 28 days after commissioning, and one operator gives 30. That operator, SP Energy Networks, shows how the two fit together on its own page: you must tell it about a small generator “before or at the time of commissioning”, which it calls a legal obligation under these regulations, and the 30 days is for sending in the commissioning form afterwards. Some of those pages are still live, and they predate plug-in solar.
That process was written for a different situation: a qualified installer, a fixed system and paperwork after the job. It has been carried across into plug-in solar articles without anyone checking it against the regulation. We have not been able to open the national plug-in registration portal ourselves, because it turns our visits away, so we cannot tell you whether it states a deadline.
One honest limit. The grid connection rules themselves, Engineering Recommendation G98, are not published freely, so we have not been able to read how G98 states the timing. What we can say is that the legal duty in regulation 22 is “before, or at the time of” switching on, and we have found nothing that changes that.
What this means for you
- Register before you plug it in. Do that and you have met the regulation, whatever any other page says about deadlines.
- It is a notification, not an application. Nobody assesses it and nobody can refuse it. It is free and takes a few minutes.
- The portal is the route, the operator is the duty. The national registration site, myplugin.solar, passes your details to the right operator. The legal duty is to make sure the operator is told.
- Already plugged one in without registering? Register now. Do not worry about which clock applies; put it right today.
- Keep the confirmation. Save, print or screenshot whatever confirmation you are given.
Our step by step guide to telling your network operator walks through the form. If you want to know which operator covers your home, put your postcode into our savings calculator and it names them. The wider rules, including the 800W limit and the one device per household, are in is plug-in solar legal in the UK.
Before you register, check that your exact model is marked Compliant on the official register. The kit tracker links each kit on sale to its own register entry.
This is general information about the published regulations, not legal advice.
Questions people ask
Do I have 28 days to register a plug-in solar kit?
No. Regulation 22(2)(c) of the Electricity Safety, Quality and Continuity Regulations 2002 requires the network operator to be advised “before, or at the time of, commissioning”, which means on or before the day you first switch the kit on. The 28 day figure comes from older guidance for installer-fitted solar. Register before you plug it in.
Is registering at myplugin.solar itself the legal requirement?
The legal duty is to make sure the network operator is told. The national portal is the simple way to do that, because it passes your details to the right operator for you. If the portal will not accept your device, contact your network operator directly rather than plugging it in.
Sources: Electricity Safety, Quality and Continuity Regulations 2002 (SI 2002/2665), regulation 22, as amended, read 26 and 27 September and again 7 October 2026; SI 2026 No. 848, read 26 September and 7 October 2026; SP Energy Networks, “Single G98 Generator Connections”, read 7 October 2026; the Plug-in Solar Device Interim Product Specification version 2, section 8.2.3.1, which requires every kit to state that notifying the network operator is mandatory; Energy Saving Trust, “Plug-in solar panels”, which names the portal. The AI answers quoted above were recorded on 28 September 2026. Engineering Recommendation G98 is not freely published and we have not read it. We name no retailers and earn no commission from this article.