The short answer
Plug-in solar panels became legal to buy and use in Great Britain on 27 August 2026. At the October to December 2026 price cap, the government's own figures work out at £112.65 a year for an 800W kit tilted at 30 degrees facing south, and £71.59 a year for the same kit hung flat on an east or west balcony. On the £500 kit the government assumes, that is a 4.4 year or a 7.0 year payback. We also read 20 Amazon UK listings on 4 November 2026: 4 sell inverters rated from 1,200W to 1,600W, above the 800 VA plug-in limit, and none mentions the government's product specification by name.
Checked 4 November 2026 · desk research by Jacob Whitmore. We have not installed or tested a plug-in solar kit. Every figure below is arithmetic on a published input: the Department for Energy Security and Net Zero (DESNZ) impact assessment, its interim product specification, GOV.UK, the Ofgem price cap, and Amazon UK listings as they read on the date stated.
Prices and specs last checked by Look Into on 4 November 2026 · next check 30 December 2026 · how we picked
What the rules actually say
GOV.UK announced on 26 August 2026 that plug-in panels would be legal to buy and use across Great Britain from 27 August. A plug-in kit is a small solar panel, or two, wired to a micro inverter that plugs into an ordinary wall socket. The electricity it makes is used by whatever is running in your home at the time.
The detail sits in the DESNZ Plug-in Solar Device Interim Product Specification, version 2.0, July 2026. The press release talks about "800W". The specification is stricter and more precise than that. These are the rules a buyer should know:
- The limit is 800 VA and 3.5 A, measured at the socket. The panels behind it can total up to 2,000W of DC power, which is why kits with 960W of panels and an 800W inverter are allowed.
- One device per household, for now. The specification allows one device per circuit, but a footnote says the network rule (Engineering Recommendation G98) still limits installations to one device per household until G98 is amended. Two kits on two sockets is not allowed today.
- A moulded UK plug to BS 1363, fused at 5A or less. Extension leads, multi-way adaptors, travel adaptors and RCD adaptors are all prohibited.
- Not on every socket. Lighting circuits and circuits feeding fixed equipment such as a cooker or boiler are excluded.
- Your network operator must be told when the device is connected and when it is disconnected. The product must carry this instruction and a link to the process.
- The device must be registered on the Energy Networks Association (ENA) platform and confirmed compliant before it is sold.
- Check your fuse box first. The specification expects modern RCBO protection. Older fuse-based installations need a professional check and possibly an upgrade.
GOV.UK also says you should check whether your property needs permission: a landlord, building owner or freeholder, planning permission, or listed building consent. If you live in a flat, our guide to solar panels for flats and apartments covers who controls the walls and balconies.
What it saves, by orientation
The government's headline is that households "could save up to £110 a year". That figure comes from Table 7 of the DESNZ final stage impact assessment, which models one 800W kit in two positions, with average UK sunshine and little or no shading. We re-priced both at the current cap rate of 26.32p per kWh (Ofgem, 1 October to 31 December 2026).
| Setup (DESNZ Table 7) | Made a year | Used at home | Saved at 26.32p |
|---|---|---|---|
| A: 30 degree tilt, facing south | 690 kWh | 428 kWh (62%) | £112.65 |
| B: hung vertically, facing east or west | 378 kWh | 272 kWh (72%) | £71.59 |
Working: 428 kWh × £0.2632 = £112.65, and 272 kWh × £0.2632 = £71.59. The government's own rounded figures of about £110 and £70 both imply a rate of about 25.7p per kWh, which is why our figures are slightly higher.
The point the headline skips: a panel hung flat on a balcony rail makes 55% of the electricity of the same panel tilted at 30 degrees facing south (378 ÷ 690). Most people buying a plug-in kit because they cannot use their roof will be closer to setup B than setup A. The "up to" in "up to £110" is doing real work.
The daytime spill: electricity you give away
A plug-in kit makes most of its power around midday, when many homes are using little. Whatever your home is not using at that moment flows out to the grid. We call the share of a kit's output that leaves this way the daytime spill.
In the government's own model, the daytime spill is 38% for the south-facing kit (262 of 690 kWh) and 28% for the balcony kit (106 of 378 kWh). Priced at the cap rate, the south-facing spill is electricity you would have paid £69.01 for if you could have used it yourself. The government response of July 2026 sets out no export payment arrangement for plug-in devices; it only records that some consultation respondents asked for one. Plan on being paid nothing for the spill.
Two things shrink the spill: running the washing machine, dishwasher or immersion heater in the middle of the day, or adding a battery. A battery changes the payback sums completely, so read our audit of usable battery capacity before paying for one.
Payback on real kit prices
The impact assessment assumes a kit costs £500 on average, that the inverter lasts around 10 years, and that a replacement inverter costs £100. Below, the same savings applied to the government's £500 and to three complete kits listed on Amazon UK on 4 November 2026. Payback is price ÷ yearly saving, with electricity held at today's rate.
| Kit (price on 4 Nov 2026) | South, 30 degrees | Balcony, east or west |
|---|---|---|
| 480W panels, 800W inverter (B0HJW1CX7X), £299.99* | 4.4 years | 7.0 years |
| 960W panels, 800W inverter (B0HDSR7DDK), £408.99 | 3.6 years | 5.7 years |
| Government assumption, £500 | 4.4 years | 7.0 years |
| 930W panels, 800 VA inverter (B0HJDMFJLV), £590.00 | 5.2 years | 8.2 years |
*The DESNZ figures are for 800W of panels. For the 480W kit we scaled the saving down in proportion (480 ÷ 800), giving £67.59 or £42.95 a year. That is a simplification: a smaller kit's output is more likely to be used in the home, so its real saving may be a little higher. The two kits with more than 800W of panels are capped at the socket, so we used the 800W figures for them without adding anything for the extra panel area.
Over the government's 15 year appraisal period, with one £100 inverter replacement and no change in the electricity price, a £500 kit facing south returns £1,089.74 more than it costs. The balcony version returns £473.86. Neither figure is discounted for inflation or for panel output falling with age.
What 20 Amazon listings tell you
On 4 November 2026 we read the first 20 unsponsored, in-stock Amazon UK listings returned by the searches "plug in solar panel kit" and "plug in solar" that sell a device to feed solar power into a home. We read the title, the bullet points, the product description and the technical specification tables. Four were complete kits with panels, one was a battery unit with a built-in inverter, and fifteen were micro inverters sold on their own.
| What the listing states | Listings (of 20) |
|---|---|
| An AC rating above the 800 VA plug-in limit (1,200W to 1,600W) | 4 |
| Names G98, the network connection rule | 5 |
| Names the ENA, where compliant devices are registered | 4 |
| States a UK plug | 3 |
| Tells you to notify your network operator | 3 |
| States the limit in VA, as the specification does | 1 |
| Names the DESNZ interim product specification | 0 |
The four listings above the limit are B0H3SZG6RQ (1,600W, £204.14), B0FW4ZWCCK (1,600W, £305.79), B0HHJKWGQF (1,200W, £152.99) and B0G2SB5FR3, which is offered in ratings from 300W up to 1,600W (from £95.99). We are not saying any of them is unsafe or illegal to sell. They are grid-tie inverters, which an electrician can install on a dedicated circuit. The point is narrower: they appear in a UK search for plug-in solar, and none of them can be the plug-in device the new rules allow.
Credit where it is due: three complete kits name G98, the ENA and network operator notification in their own listing (B0HDSR7DDK, B0HJW1CX7X and B0HJDMFJLV), and B0HJDMFJLV is the only one of the 20 to state its inverter rating in VA. Those three tell a buyer more than any bare inverter in the sample.
Before you buy
- Be honest about where it will go. If the only spot is a vertical balcony rail facing east or west, plan on about £72 a year, not £110.
- Look for the ENA registration and a G98 statement on the product itself. If the listing does not mention either, ask the seller before paying.
- Check the inverter rating is 800 VA or less, with a moulded UK plug. A 1,200W or 1,600W inverter is not a plug-in device under the new rules.
- Buy one kit, not two. The one-per-household rule stands until G98 changes.
- Look at your fuse box. If it has old rewireable fuses rather than RCBOs, budget for an electrician's check first.
- Get permission if you rent, own a leasehold flat or live in a listed building.
- Tell your network operator when you plug it in, and again if you take it away.
If your roof is an option, a full system makes far more electricity per pound of effort. See our solar panel costs guide and solar battery storage guide.
Frequently asked questions
Are plug-in solar panels legal in the UK?
Yes, in Great Britain since 27 August 2026, according to GOV.UK, for devices that meet the DESNZ interim product specification. The output limit is 800 VA and 3.5 A, and you must notify your network operator.
How much do plug-in solar panels save a year?
At the October to December 2026 cap rate of 26.32p per kWh, the government's own model gives £112.65 a year for an 800W kit tilted at 30 degrees facing south, and £71.59 for one hung vertically facing east or west.
Can I plug in two kits?
Not yet. The specification allows one device per circuit, but it says the current G98 rule limits installations to one device per household until G98 is amended.
Do I get paid for the electricity I export?
The July 2026 government response sets out no export payment arrangement for plug-in devices. In the government's own model, 28% to 38% of a kit's output is exported, so it pays to use power in the middle of the day.
Can I use an extension lead?
No. The specification prohibits extension leads, multi-way adaptors, travel adaptors and RCD adaptors. The kit must plug straight into a wall socket that is not on a lighting circuit or a circuit for fixed equipment.
How Look Into made this guide
Desk research, checked 4 November 2026. Savings come from Table 7 of the DESNZ plug-in solar final stage impact assessment, re-priced at the Ofgem cap rate for 1 October to 31 December 2026 (26.32p per kWh). Rules come from the DESNZ Interim Product Specification v2.0 (July 2026), the DESNZ government response (July 2026) and GOV.UK (26 August 2026). The listing audit covers the first 20 unsponsored, in-stock Amazon UK results for two searches, read in full on 4 November 2026. Prices change; every price here is dated.
This page has no affiliate links. Because the Amazon prices are part of the research, we do not link to the listings.
What this guide could not check
- Real-world output of any kit: we have not installed one, so savings are the DESNZ model re-priced, not measured
- Whether the four inverters above 800 VA are sold with any UK plug-in claim beyond their search placement
- Whether each kit that names G98 is actually listed on the ENA register today
- Electricity price beyond 31 December 2026: savings move with every quarterly cap
- Panel output loss with age, which the 15 year figures do not discount
Sources: GOV.UK, Households can save as plug-in solar panels come to market (26 August 2026) · DESNZ, Plug-in Solar Device Interim Product Specification v2.0 · DESNZ, Plug-in solar: government response (July 2026) · DESNZ, Plug-in solar final stage impact assessment · Ofgem energy price cap, 1 October to 31 December 2026.