Last reviewed: 4 September 2026. Checked against SI 2026/848, the DESNZ Interim Product Specification version 2.0 (July 2026) and ENA Engineering Recommendation G98 Issue 2 Amendment 1.
No. One plug-in solar kit per household. That is the rule today, it is a network connection rule rather than a product rule, and it applies however many circuits, sockets or outbuildings you have. There is a genuine complication worth understanding — the government’s product specification is written around a more generous “one per final circuit” limit — but that limit is not in force. The Interim Product Specification says so itself, in a footnote it repeats five separate times: while the specification permits one device per final circuit, GB network connection requirements restrict this to one device per household, and that applies unless and until G98 is amended.
The two rules, and which one binds you
Plug-in solar sits under two separate regimes and people routinely quote one at the other.
| Document | What it governs | What it says about number | Status today |
|---|---|---|---|
| SI 2026/848 | Whether the device may lawfully be used at all | Nothing. It defines a plug-in microgenerator by its 800 W AC ceiling and excludes storage; it sets no quantity | In force since 27 August 2026 in England, Wales and Scotland |
| DESNZ Interim Product Specification v2.0 | What a compliant product must be and must say | “Only one plug-in solar product shall be used per household final ring circuit”; the plug and the instructions must both carry that statement | Published July 2026, but expressly subordinate to G98 on this point |
| ENA Engineering Recommendation G98 Issue 2 Amendment 1 | Connecting generation in parallel with the low-voltage network | One device per household | In force, and the binding limit until amended |
So the practical answer is the strictest of the three: one. A second kit is not a grey area you can argue your way through by pointing at the specification — the specification defers to G98 in its own text, in its scope clause and in footnotes attached to every clause where the number appears.
Why the per-circuit rule exists at all
The circuit-level limit is the engineering one, and it is worth understanding because it explains what the household limit is protecting against and what will happen if the rule changes.
A plug-in inverter injects up to 3.5 A into a final circuit at a point downstream of that circuit’s protective device. The device therefore cannot see the whole current the conductors are carrying — the principle BS 7671 deals with at section 551.7.2. On a 32 A ring final circuit, 3.5 A is a small fraction of the rating and the DESNZ-commissioned study of plug-in PV on UK ring final circuits concluded there was no barrier under defined limits. Put two devices on the same circuit and you double the injected current; put four on it and you are into territory nobody has assessed. Hence the specification’s wording: one product per household final ring circuit, “to ensure the currents flowing through the electrical connection to the consumer unit remain within safe levels”.
The specification even works the examples through, in the guidance it requires manufacturers to give consumers about identifying circuits: a device in a bedroom and another in a kitchen would be acceptable if those sockets are on different circuits; two devices on sockets in the same room or area is not permitted if those sockets switch off together; a device on a spur supplying fixed equipment such as a cooker or a boiler is not permitted; and a device on a lighting circuit is not permitted at all.
Read that carefully: it describes the world after G98 changes, not the world today. Today the household limit bites first, so the circuit arithmetic never becomes your problem.
Why the household limit exists
The household limit is a network rule, not a house-wiring rule. Your distribution network operator sizes its cables, transformers and voltage control on assumptions about how much embedded generation sits behind each connection. G98 is the “fully type tested micro-generator” route: it works precisely because each device is small, standardised and countable, and the operator can rely on the count. Notification is what keeps that record accurate — which is also why the specification requires kits to state that notifying the DNO of both connection and disconnection is mandatory.
Multiple devices behind one meter is exactly the case where a per-device notification stops telling the operator anything useful. Until G98 is amended to handle it, the answer is one. See notifying your DNO and how to fill in a G98 notification.
The workarounds people ask about, and why they are not workarounds
- “Two kits, one in the house and one in the garage.” Same household, same connection, same meter. One device.
- “A second kit on a different circuit.” That is the specification’s future rule, not the current network rule. One device.
- “Two 400 W kits instead of one 800 W kit.” The limit counts devices, not watts. Two devices is two devices.
- “A kit each for me and my flatmate.” One household, one connection. One device.
- “Two flats in one converted house.” This one may genuinely be two, because it may be two households with two separate supplies and two MPANs. Ask your DNO before you buy, and see plug-in solar in a leasehold flat.
- “More panels behind the one inverter.” This is the legitimate route, and it is not a workaround at all — see below.
What you can legitimately do instead
If 800 W is not enough, the specification gives you headroom in the direction that does not involve a second device:
- Up to 2,000 W of PV modules behind the single 800 VA inverter — a figure that comes from the specification, not from SI 2026/848.
- Up to four modules, with no more than two in series in any string, and an open-circuit voltage at the inverter inputs that must not exceed 120 V DC.
- Above 960 W of total module capacity, manufacturers must advise you to consider a professional assessment of your existing installation first. That is advice, not a prohibition — but it is in the document, and it is sensible.
Oversizing the DC side is normal engineering, not a loophole: it lifts output in poor light and in winter, at the cost of clipping the summer peak the inverter cannot pass. See how many panels behind an 800 W inverter and plug-in solar in winter.
If you need genuinely more than that, you are no longer shopping for a plug-in kit. You are shopping for a certified rooftop or ground-mounted installation, with an installer, a certificate and — unlike a plug-in kit — access to export payments. See plug-in solar vs rooftop solar.
What happens if you install two anyway
We would rather give you the honest answer than a scare story. Nobody inspects domestic gardens for second solar panels, and there is no enforcement officer to knock on your door. What is true is narrower and more expensive:
- You would be operating outside the connection agreement that makes the installation lawful under the “connect and notify” route, and the notification you sent would be inaccurate.
- You would be installing contrary to the manufacturer’s instructions, which every warranty is conditioned on, and contrary to a statement the manufacturer is required to print on the plug itself.
- If two devices ended up on the same final circuit, you would have doubled the injected current on a circuit whose protective device cannot see it — the one genuinely unsafe outcome in this list.
- Your insurer will read the manufacturer’s instructions before it reads ours. See does plug-in solar affect home insurance.
Frequently asked questions
Will the one-per-household limit change?
The government’s intention is that it should: the specification is written for one device per final circuit and each mention carries a footnote anticipating the amendment to G98. We have no date. [VERIFICAR: whether the ENA has published a timetable for the G98 amendment that would move the limit from per-household to per-final-circuit] — when it lands, this page changes and we will date the change.
Does a rooftop array count towards the limit?
It is separately notified generation on the same installation and your DNO will hold both records. The one-device limit is specific to plug-in devices, but the operator’s view of your connection is not — declare everything.
Can I move my one kit between sockets?
Yes, subject to the same rules about which circuits are permitted: socket circuits only, never lighting circuits and never a spur feeding fixed equipment, and never through an extension lead or adaptor. See extension leads and plug-in solar.
How do I find out which sockets share a circuit?
Switch one breaker off at the consumer unit and see which sockets lose power; those that go off together are on one circuit. The specification requires manufacturers to supply this guidance — and to tell you to consult a professional electrician if you are unsure how to do it safely, or if the consumer unit is unlabelled, of unknown condition or still uses older rewireable fuses. See do I need an electrician.
I already have two. What now?
Take one out of service, and notify your DNO of the removal — the specification treats disconnection as notifiable in the same way as connection. See telling your DNO you removed a device.
Primary sources.
DESNZ, Plug-in Solar Device Interim Product Specification version 2.0, July 2026 (PDF) ·
SI 2026/848 (legislation.gov.uk) ·
Energy Networks Association, G98 and G99 documents and forms ·
ENA, find my network operator.
General information, not electrical advice. Anything touching fixed wiring or the consumer unit is work for a competent electrician working to BS 7671 — see our editorial methodology.