Battery power

A common question about plug-in solar is whether you can add a battery to store what you generate for use after dark. Short answer: no. Batteries that plug into a socket and feed stored power back into your home's wiring are not permitted under the current rules, and every compliant plug-in solar kit must carry a warning not to be used with battery storage. This page explains what the rules say, what is still possible, and the safety standards to look for in a battery product.

A plug-in solar kit must connect directly into a wall socket. Do not use extension leads, multi-way adaptors, travel adaptors or RCD adaptors - the Interim Product Specification requires a direct plug-to-socket connection. See Extension leads for why.

Regulatory status: plug-in batteries are not permitted

The Interim Product Specification covers solar-only products: panels, an inverter, a lead with a standard plug, and a mounting system. Plug-in battery systems and solar products with built-in batteries are outside its scope. The law (SI 2026/848) defines a plug-in microgenerator as a device that is not designed to import electricity from your home to store it for later. And Ofgem's decision on the G98 amendment (11 August 2026) says plug-in electricity storage devices "will therefore remain prohibited from being sold, supplied, or used in the UK".

The specification also requires every compliant kit's instructions to carry a prominent warning that it is not intended to be connected to, operated with, or used in conjunction with a battery energy storage system.

DESNZ says battery-integrated products remain outside the framework but that it "will continue to consider the evidence base as part of future work". There is no timeline or commitment, and nothing had changed as of this page's last check.

A home battery is still possible as a separate, professionally installed system: hard-wired by a qualified electrician (normally notifiable work under Part P of the Building Regulations in England and Wales) and notified to your network operator under G98 or G99, like any other home storage. That is a different route from plug-in solar altogether. If you already have, or are planning, a home battery, ask the installer and your network operator before also using a plug-in solar kit in the same home, given the specification's battery warning.

It is also worth checking your insurance before you install one. Adding battery storage - particularly if it is not installed, certified or notified by a qualified electrician - can be a material change your insurer expects to be told about; not disclosing it risks a claim being reduced or a contents or buildings policy being invalidated later. Check directly with your insurer before you buy or install anything.

In practice, "battery power" alongside a plug-in solar kit usually means one of two different things:

  • A portable power stationProducts from brands like EcoFlow, Anker SOLIX and BLUETTI - a battery-plus-inverter box you charge from its own dedicated solar panel input, or plug in to charge like any appliance, and then use separately, e.g. for camping, a shed, or backup lighting. Used that way it does not feed power back into your home's wiring. Do not connect your plug-in solar kit to it, or use it to feed power back into a socket.
  • A plug-in (AC-coupled) home batteryA battery that plugs into a normal socket, charges from your home's wiring and discharges back into it later. This is a plug-in electricity storage device, and it is not permitted in the UK under the current rules - with or without a plug-in solar kit.

Because batteries are outside the specification, no battery product can be listed on the ENA's Type Test Register as part of a compliant plug-in solar kit - be wary of any "plug-in solar with battery" bundle marketed as compliant. See Certification.

AC-coupled vs DC-coupled, in plain terms

DC-coupled means the battery sits between the panels and the inverter, storing DC power before it is converted to mains AC - this is how most full rooftop-solar-plus-battery installations work, using a hybrid inverter designed for it. AC-coupled means the battery has its own separate inverter and charges from the AC power in your home's wiring. For plug-in solar, neither is an option today: a solar product with a built-in battery is outside the specification, and a separate battery that plugs into a socket is a plug-in storage device, which remains prohibited. Both are possible only as part of a professionally installed and notified system.

Battery safety standards to look for

These apply to portable power stations and to batteries in a professionally installed home system - not to plug-in batteries, which are not permitted.

  • Cell/pack safety standardBS EN IEC 62619 (safety of lithium batteries for stationary uses, including home storage); portable products commonly reference BS EN IEC 62133 instead
  • Home battery installationA professionally installed home battery should follow PAS 63100:2024, BSI's specification for protecting against fire from battery storage in homes - ask your installer
  • Transport/handling standardUN 38.3 testing, referenced on the product's documentation, for how the battery has been shown to behave under shock/vibration/thermal stress
  • General product markingCE and/or UKCA marking - see Certification for what these marks actually mean
  • Ventilation and placementDo not enclose a battery tightly, cover it with fabric, or store it somewhere it can overheat (direct summer sun in a conservatory, next to a radiator); follow the manufacturer's stated clearances
  • Fire safetyLithium battery fires are rare but can be intense and fast-developing - keep a battery away from escape routes where practical, and check your smoke alarm coverage extends to wherever it is stored/charged

Sources

Rules last checked: 29 October 2026, against the Interim Product Specification v2 (16 July 2026), SI 2026/848 and Ofgem's G98 decision of 11 August 2026. The specification has not been updated or replaced since July 2026.

This page is informational, not electrical-safety advice for a specific product. If you are considering a home battery, use a qualified installer and tell your network operator.