What a plug-in kit is, in law
A plug-in solar kit is a panel, or a small set of panels, that connects to the house through a plug rather than being wired in by an installer. The regulations that made it legal to sell, SI 2026/848, define it as equipment that turns sunlight directly into electricity, has a maximum rated AC output not exceeding 800 watts, connects to a home's wiring through a standard plug and socket and runs alongside the network; and they say it must not be installed or operated unless it complies with the government's Plug-in Solar Device Interim Product Specification (SI 2026/848). The rules took effect on 27 August 2026, and GOV.UK says the kits can go in any outdoor space or on some balconies (GOV.UK).
The 800 W limit is the kit's rated AC output, what comes out of the plug, not the total of the panels behind it. It is a small fraction of a roof system: the Energy Saving Trust puts a typical home system at 4.5 kWp (Energy Saving Trust), more than 5 times a kit's rating by our arithmetic. The same regulations amend the rules on plugs and sockets so that standard plugs intended for plug-in kits can be approved, and the definition rules out a device designed to draw power from the house and store it for later, so a plug-in battery falls outside it (SI 2026/848).
Where England's planning rules allow one
In England the permitted development rules were changed on the same date to cover plug-in solar (SI 2026/896). On the house itself, plug-in solar is not permitted development where any part of it would sit on a wooden wall, balcony or enclosure, or on an outside part of the house clad in timber; and equipment on a wall must not stand out more than 0.4 metres from it, or 0.2 metres where the wall is next to a highway such as a pavement. In the garden, a plug-in kit cannot be fixed to a wooden fence, gate, wall or other enclosure, and stand-alone panels have height limits and a cap of 9 square metres on their surface area. Planning rules decide where a kit may go, not whether it is safe; safety is the job of the product specification the kit has to meet, which is why the checks before buying, further down, start with the product.
Listed buildings and conservation areas are where the answer changes. The rules give no permitted development for solar on a listed house, or for stand-alone panels within its grounds, and in a conservation area they exclude a wall, balcony or roof enclosure that fronts a highway. Wigan Council lists 23 conservation areas, from Haigh Village and Wigan Pier to Astley Village in Tyldesley and Pennington in Leigh (Wigan Council). Historic England counts 353 listed building entries in the borough, 321 of them grade II (Historic England). If you live in a conservation area or a listed building, ask the council before buying. Planning and conservation areas has the full list and the rules for roof systems.
Tenancies, leases and flats
Permission is not only about planning. GOV.UK advises checking, before buying or installing a kit, whether any permissions are needed, which may include a landlord's or the building owner's, planning permission or listed building consent, and it notes that decisions on those requests rest with landlords, building owners or councils (GOV.UK).
That matters in the borough, where 15.9% of households rent privately and 17.0% from a social landlord (Census 2021), and 7.4% live in a flat (Census 2021). A tenancy may say nothing about solar but plenty about fixings and the outside of the building, and a lease may control the balcony and the outside walls. Flats are far commoner in the town centre: in Wigan Central ward 22.0% of households live in one (Census 2021), and many of those balconies and walls may belong to a building owner rather than the resident. Ask in writing, and keep the answer. Renting and solar covers how to put the request to a landlord.
What a kit makes, compared with a roof
Treat a kit as 0.8 kW of panels and the PVGIS figures for central Wigan give a rough yearly output; this is our arithmetic, not a measurement (PVGIS 5.3). Facing south on a frame tilted at 35°, that is about 742 kWh a year; facing east or west, about 590 or 594 kWh; laid flat, about 622 kWh. The same south slope carrying a 4 kW roof system gives 3,708 kWh. Against Ofgem's typical household use of 2,500 kWh a year (Ofgem), a south-facing kit covers about 30% by the same arithmetic, before allowing for the power it makes when nobody is using any. Month by month the swing is wide: about 92 kWh in June and 22 kWh in December from the same south-facing kit, by our arithmetic from the PVGIS months.
| Facing | 0.8 kW kit, kWh a year | 4 kW roof, kWh a year |
|---|---|---|
| South | 742 | 3,708 |
| South-east | 698 | 3,492 |
| South-west | 702 | 3,508 |
| East | 590 | 2,948 |
| West | 594 | 2,972 |
| North | 407 | 2,036 |
| Laid flat (0°) | 622 | 3,108 |
| Upright on a wall or rail (90°) | No figure in these runs | Not applicable |
One gap matters for balconies. The PVGIS runs behind this site stop at a 50° tilt, so there is no figure here for a panel hung upright on a wall or a balcony rail, and the table should not be read as giving one. Real output also depends on shade from neighbouring buildings and trees, which these runs do not include. If a seller quotes a yearly figure for an upright kit, ask how it was worked out. Direction matters more than address: a kit facing north at 35° makes about 407 kWh a year, roughly 55% of the same kit facing south, by our arithmetic. Other parts of the borough are on output across the borough.
No MCS certificate, so plan to use it at home
A roof system comes with an installer and an MCS certificate; a kit you set up yourself has neither. That has a practical consequence. GOV.UK's eligibility for an export tariff asks for the installation and the installer to be certified through MCS or an equivalent scheme (GOV.UK), so do not plan on being paid for what a kit sends out; its value lies in the power the house uses while it is generating. MCS certificates are issued for installations by certified installers, so a kit you set up yourself has none to register. Export payments explains how the tariffs work for roof systems.
On the network side, Electricity North West's own page says anyone planning to connect generation or storage to its network must inform it or complete an application (Electricity North West). Ask the seller what notification its kit needs, and keep whatever it gives you with the receipt.
Before you buy a kit
A kit is sold rather than installed, so the checks move from the firm to the product and the spot it will go. Before paying, confirm in writing that the kit states compliance with the Interim Product Specification and has a rated AC output of no more than 800 W; that the place you have in mind is not timber and, in a conservation area, does not face the road; and that anyone whose permission you need has given it. This guide gives no kit prices and names no brands. Keep the receipt and the product documents together, because they are the only record that the kit you bought met the specification on the day you bought it. A kit, unlike a roof system, can go with you when you move, so the receipt and documents should go with it.
If the aim is to make a real share of the household's electricity, a kit is not a substitute for a roof system. Compare the figures above with a roof quote, the price of that quote with the North West means on the costs page, and the firm with the checks on checking a solar installer. Short answers to other questions are on the FAQs page.