The 2026 plug-in solar rules, S.I. 2026/848, in force on 27 August 2026, cover only solar devices rated at up to 800 W, and their definition excludes a device designed to take electricity from your wiring and store it for later. DESNZ says the product specification "does not extend to other plug-in technologies, such as plug-in batteries". It has planned a plug-in batteries safety study with estimated contract dates of 5 October 2026 to 31 March 2028, so there is no rule yet for connecting a battery through a plug. The route that exists today is an installed battery, notified to the network operator under G98 or applied for under G99.
What the 2026 plug-in solar rules allow
The change is a statutory instrument, S.I. 2026/848, signed on 16 July 2026 and in force from 27 August 2026. It amends two sets of regulations: the Plugs and Sockets etc. (Safety) Regulations 1994, so that a plug for a plug-in microgenerator can be approved even though BS 1363 forbids using a plug to connect a generating device to a socket, and the Electricity Safety, Quality and Continuity Regulations 2002, so that a plug-in microgenerator must meet the government’s Plug-in Solar Device Interim Product Specification, version 2, published on 16 July 2026. The plug changes extend across the UK; the electricity safety change extends to England, Wales and Scotland.
Whether a device counts as a “plug-in microgenerator” turns on five tests in the regulations:
| Test | What the regulations require |
|---|---|
| Source | It “generates electricity from the direct conversion of sunlight into electricity” |
| Size | Its maximum rated alternating current output does not exceed 800 watts |
| Connection | It is intended for connection to a low voltage consumer’s installation by a standard plug and socket |
| Operation | It is designed to operate in parallel with a distributor’s network |
| Storage | It “is not designed to import electrical energy from a low voltage consumer’s installation for the purpose of storing energy for later supply”, other than for control or auxiliary functions the interim specification permits |
Why a plug-in battery is outside them
The last test is the one that matters here. A plug-in battery that charges from your sockets is, by design, a device that imports electricity from your installation to store it and supply it later. It fails the definition on the fifth line, and DESNZ says so in plain terms. In its outcome to the consultation, published on 16 July 2026, the department states that the interim specification “applies specifically to plug-in solar products only and does not extend to other plug-in technologies, such as plug-in batteries”. The consultation described the aim as letting consumers connect plug-in solar systems without batteries to a standard mains socket, and the outcome records respondents’ worry that the changes could be wrongly interpreted as applying to plug-in batteries.
That makes a practical difference to anyone shopping online. Only plug-in solar devices that comply with the specification can be sold in the UK and plugged in under the amendment. A battery sold with the same plug-in language is outside it, and DESNZ describes its planned study as informing the technical standards a plug-in battery would need.
What DESNZ is doing about plug-in batteries
The department has begun the process of finding out. A planned procurement notice on Find a Tender, published on 17 August 2026 under the title Plug-in batteries safety study, sets out a study with these features:
- Scope: the safety and risk considerations for plug-in batteries with up to 800 W of AC mains output in the UK context, to inform technical standards and assess whether safe plug-in batteries for UK homes are feasible.
- Phase 1: evaluate plug-in self-installed battery products on sale around the world, for example from Anker, Fox, Lidl and EcoFlow, and the hazards of installing them DIY, including fire incidence compared with other batteries.
- Standards: review the electrical and battery standards that would apply, including BS 7671, PAS 63100 and MIS 3012, and identify where standards written for installed home batteries leave gaps for plug-in ones.
- Output: recommend the technical and regulatory changes that would permit legal, safe use of plug-in batteries. A second phase depends on budget and on what phase 1 finds.
- Timing and cost: estimated contract dates of 5 October 2026 to 31 March 2028, and an estimated value of £250,000 excluding VAT.
The notice is a planned procurement, so these dates and figures are estimates, and no findings have been published. The estimated contract runs for about 18 months, so any change to the rules would come after it.
What you can do now
- Plug-in solar without a battery, if the device complies with the interim specification and its plug is approved. That is what the 2026 rules were written for.
- An installed battery. An installation within 16 A per phase, 3.68 kW on single phase, is fitted first and notified to the network operator within 28 days of commissioning under G98; a larger one needs a G99 application beforehand. Our guide to G98 and G99 sets out which applies and how long it takes. The installer should be MCS certified for batteries under MIS 3012 and follow PAS 63100 on location, which rules out bedrooms, escape routes and lofts; see PAS 63100 explained.
- A battery without solar panels. Installed batteries work on a time-of-use tariff without panels; the model results are on our battery without solar page.
What an installed battery costs, for comparison
We have not priced plug-in batteries, because no UK rule covers them and a marketplace price would be for equipment outside the new framework. For installed batteries, these are published prices and the official medians:
| Installed battery | Usable capacity | Price | Per usable kWh |
|---|---|---|---|
| One Enphase IQ Battery 5P (Octopus) | 5.0 kWh | £3,947 | about £789 |
| Fox ESS EVO 10 (Octopus) | about 9.7 kWh | £5,336 | about £550 |
| Two Enphase IQ Battery 5P (Octopus) | 10.0 kWh | £5,336 | about £534 |
| Tesla Powerwall 3 (Octopus) | 13.5 kWh | £7,999 | about £593 |
| Official median, under 6 kWh | £1,300 | ||
| Official median, 6 to 11 kWh | £890 | ||
| Official median, 11 kWh or more | £630 |
Octopus’s prices are April 2026 installed prices; the medians are DESNZ’s for MCS-certified batteries in existing homes in 2025/26. Installed home batteries carry 0% VAT until 31 March 2027, according to HMRC’s VAT Notice 708/6. If the question behind your search is how to get a battery without a large installation, our page on the 5kWh battery shows the smallest installed option, and you can compare written battery storage quotes (we reply by email) with the calculator before you decide.
Questions people ask
Is a plug-in solar battery legal in the UK?
The new plug-in solar rules do not cover batteries. S.I. 2026/848 applies only to solar devices of up to 800 W, and DESNZ says its product specification does not extend to plug-in batteries. No UK rule yet sets out how a battery could be connected through a plug, and DESNZ has planned a safety study to assess whether it can be done safely.
Do the 2026 plug-in solar regulations cover a solar panel with a battery?
DESNZ's consultation described the aim as letting consumers connect plug-in solar systems without batteries to a standard mains socket. The statutory definition requires a solar device that is not designed to import electricity from your installation for storage and later supply, other than for control or auxiliary functions that the interim product specification permits.
When will plug-in batteries be allowed in the UK?
There is no date. DESNZ's planned procurement notice for a plug-in batteries safety study gives estimated contract dates of 5 October 2026 to 31 March 2028 and says the study will inform technical standards and assess the feasibility of safe plug-in batteries for UK domestic use. Any change to the rules would follow the study.
Which products will the DESNZ study look at?
Its notice says phase 1 will evaluate plug-in self-installed battery products on sale around the world, for example from Anker, Fox, Lidl and EcoFlow, and the safety risks of installing them DIY, including fire incidence compared with other batteries. It covers batteries with up to 800 W of AC mains output.
What is the alternative to a plug-in battery?
An installed battery. An installation within 16 A per phase, 3.68 kW on a single-phase supply, is notified to the network operator within 28 days of commissioning under G98; a larger one needs a G99 application first. The installer should be MCS certified under MIS 3012 and follow PAS 63100 on where the battery can go, and installed batteries carry 0% VAT until 31 March 2027.