Battery power

Regulatory status: not yet part of the plug-in solar scheme

The DESNZ Interim Product Specification that makes plug-in solar legal covers the panels-plus-microinverter combination only - it doesn't define a compliant "plug-in solar-plus-battery" product category, and myplugin.solar's registration form doesn't ask about one. DESNZ has said battery storage is currently outside the scope of that consultation but that it "will continue to consider the evidence base as part of future work" - so the rules may extend to batteries at some point, but there's no confirmed timeline or commitment, and nothing has changed yet. A separate DESNZ-linked safety and risk study is also looking at self-installed plug-in batteries, but that's early-stage research, not legislation.

Adding battery storage today therefore sits outside the simplified, self-install route altogether. Installing a battery - especially anything hard-wired into your consumer unit rather than simply plugged into a socket - is normally treated as notifiable electrical work under Part P of the Building Regulations, which in practice means using a registered/qualified electrician rather than doing it yourself. You're also relying on your own judgement (or your electrician's) about safety and compatibility with your plug-in kit, rather than any risk-assessed scheme covering the combination.

It's also worth checking your insurance before you install one. Adding battery storage - particularly if it isn't 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. There's no plug-in-solar-specific insurance guidance to point to here, so 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 station charged partly by the sunProducts from brands like EcoFlow, Anker SOLIX and BLUETTI - a battery-plus-inverter box you charge from its own dedicated solar input (not from your plug-in kit's mains-facing output) and then draw down separately, e.g. for camping, a shed, or backup lighting. This doesn't interact with your home's wiring at all in the way the plug-in kit does.
• AC-coupled home batteryA battery that itself plugs into a normal socket and charges from whatever's on your home circuit (including surplus plug-in solar output, if any is on the circuit at the time) then discharges back into the same circuit later. This DOES interact with your home wiring, and needs its own compliance/safety marking - it's a distinct product from the solar kit.

As of this page's last check, none of the major portable-power-station brands had a battery product confirmed on the ENA's Type Test Register specifically as part of a compliant plug-in solar kit - see Certification.

AC-coupled vs DC-coupled, in plain terms

DC-coupled means the battery sits between the panels and the inverter, storing raw DC power before it's ever converted to mains AC - this is how most full rooftop-solar-plus-battery installations work, but it requires the inverter itself to be designed for it, which the simple, fixed plug-in microinverters currently on the market are not. AC-coupled means the battery has its own separate inverter and charges from whatever AC power happens to be available on the circuit it's plugged into - simpler to retrofit onto an existing plug-in kit in principle, but it means two inverters (the solar kit's and the battery's) are both connected to the same socket/circuit, each with anti-islanding logic that needs to behave safely together. Get advice specific to the exact battery product before combining it with a plug-in solar kit on the same circuit.

Battery safety standards to look for

• Cell/pack safety standardBS EN IEC 62619 (safety requirements for secondary lithium cells and batteries) is the standard reputable UK-sold home/portable battery products should meet
• 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 placementDon't 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's stored/charged

Sources

• GOV.UK: Plug-in solar - regulatory amendment and interim product specification (DESNZ, July 2026) - confirms the scope is panels-plus-inverter, not battery storage.
• Brand affiliate/product research (EcoFlow, Anker SOLIX, BLUETTI) - internal scouting notes, not embedded on the live site; cross-checked against each brand's own UK product pages.

This page is informational, not electrical-safety advice for a specific product. If you're combining a battery with a plug-in solar kit on the same circuit, get manufacturer guidance or a qualified electrician's opinion first.