What the law now allows
Two sets of rules changed on 27 August 2026. The first, SI 2026/848, deals with the product. It defines a plug-in microgenerator as a source of electricity from sunlight with a maximum rated AC output of no more than 800 W, intended to connect to a home's wiring through a standard plug and socket, designed to run alongside the network, and not designed to draw power from the house to store it for later, beyond the control functions the government's interim product specification allows (SI 2026/848). Kits must meet that specification, and the plug must be of a type a notified body has accepted for the purpose.
The Energy Saving Trust fills in the practical side. Kits that meet the standards are legal to use in Great Britain from that date. A home may have only one plug-in device, which can be made up of more than one panel, and devices must not be linked together. Each must be registered before use on the UK plug-in solar registration website, with your name, postcode and the kit's make and model. Kits switch off in a power cut, and those with built-in batteries are not covered by the current rules (Energy Saving Trust). Before buying, the Trust suggests checking the product's specification against the UK rules, and says a list of compliant products is kept on the Energy Networks Association's Connect Direct service. A kit that is not on that list is worth a second question to the seller.
Planning: where a kit may and may not go
The second change, SI 2026/896, amended England's permitted development rules for solar on homes. Plug-in solar now counts as solar PV in those rules, so a kit on a house is permitted development unless one of the exclusions applies (SI 2026/896). The Planning Portal notes that the change blocks plug-in solar on wooden structures and cladding to reduce fire risk (Planning Portal).
On a house, a kit is not permitted development if any part of it would be on a wooden wall, balcony or enclosure, or on a part of the house clad in timber. Panels on a wall must not stick out more than 0.2 m where the wall abuts a highway, or 0.4 m elsewhere. In a conservation area or a World Heritage Site, solar on a wall, balcony or roof enclosure that fronts a highway is excluded, and nothing on a listed building is covered. A kit standing on its own in the garden falls under a separate class: it may not be fixed to a wooden fence, gate, wall or other enclosure, there are height limits near the boundary, and it is not covered within the grounds of a listed building or, in a World Heritage Site, near the boundary or between the house and the road.
Listed homes, Saltaire and the conservation areas
Those exclusions matter more in this district than in most. Historic England counts 2,290 listed buildings in the Bradford district (Historic England), and Saltaire was inscribed as a World Heritage Site in 2001 (UNESCO).
In Saltaire the position is stricter still. Bradford Council says an Article 4 direction made in 1976 removed permitted development rights for external alterations and extensions to homes in the defined area, and that every property in that area became a listed building in 1984, so listed building consent is needed for all alterations (Bradford Council). A kit on the front of a Saltaire terrace, or even one set up in the back yard within the grounds of a listed building, is outside the permitted development rules. Ask the council before buying.
The district's other Article 4 directions, in Apsley Crescent, Little Horton and Manningham, deal with dormer windows and with painting stone or exteriors; none of the directions mentions solar panels. The council also lists 60 conservation areas across the district (Bradford Council). In those, the rule to watch is the one about walls, balconies and roof enclosures that front a highway; if you are unsure whether your street is in one, or whether a spot counts as fronting the highway, ask the council. The question to put is a short one: does the wall, balcony or roof enclosure I have in mind front a highway, and is the house listed? The planning guide covers roof systems in the same areas.
What a kit makes here (our arithmetic)
There is no PVGIS run on this site for panels hung upright, at 90°, on a wall or balcony rail, so this guide gives no figure for that position. The runs cover frames tilted at 35° and panels laid flat. An upright kit would make less than the tilted figures below, by an amount this guide cannot state. The table treats a kit as 0.8 kW and multiplies it by the PVGIS figures for six places (PVGIS 5.3).
| Place | South, 35° | East, 35° | West, 35° | Laid flat |
|---|---|---|---|---|
| City centre | 747 | 594 | 588 | 619 |
| Idle | 753 | 598 | 590 | 622 |
| Saltaire | 746 | 593 | 587 | 618 |
| Keighley | 734 | 585 | 587 | 616 |
| Ilkley | 738 | 588 | 587 | 620 |
| Haworth | 725 | 583 | 574 | 614 |
On a south-facing frame in the city centre, a kit makes about 747 kWh a year, around 30% of Ofgem's typical domestic use of 2,500 kWh (Ofgem). Facing east gives up about 21% of that and laying the panels flat about 17%, by our arithmetic. The Energy Saving Trust advises against facing a kit north. How much of the output the house uses depends on what is running while the sun is out, and most suppliers will not pay for the rest without an MCS certificate, as the export guide explains.
The year also hides a steep seasonal swing. On a south frame in the city centre, a kit makes about 90 kWh in June and 23 kWh in December, by our arithmetic from PVGIS's monthly figures. In practice a kit is a spring-and-summer helper for everyday loads such as lights, laptops and the television, the kind of appliances the Energy Saving Trust lists, rather than something to lean on in midwinter.
Tenants and flats
A kit is the one form of solar a tenant can own outright, but it still needs consent. The Energy Saving Trust says renters and flat owners need permission from their landlord, or from whoever owns the building, before installing one, that you can take the kit with you when you move, and that you should check with your insurer whether your policy needs changing (Energy Saving Trust). It also says the kits currently on sale in the UK suit gardens better than balconies, and that a balcony needs a suitable frame or anchors. If the landlord agrees, get it in writing, including where the kit may stand and how it is to be fixed, so there is no argument about it when you move out.
For blocks of flats the planning rules run in parallel: no kit on a wooden wall, balcony or enclosure or on timber cladding, and nothing on a listed block (SI 2026/896). The renting guide covers how to put the request to a landlord.
A kit or a roof system?
The two are not really rivals. The Energy Saving Trust puts a typical home roof system at 4.5 kWp (Energy Saving Trust); facing south in the city centre that would make about 4,203 kWh a year, against the kit's 747, by our arithmetic. A roof system is fitted by an installer certified by MCS, notified to Northern Powergrid, and can earn an export tariff; the network guide explains the notification. A kit is self-installed, registered by you, and can move house with you.
A kit suits a home where the roof is shaded, crowded with chimney stacks and dormers, or not yours to change; the stone terraces guide looks at roofs like that. If the roof is clear and yours, compare like with like using the house-age estimator and what solar costs in the district. This guide prints no kit prices, because the market is new and prices are moving. Terms such as microinverter and AC output are explained in the glossary.
A kit does not rule out a roof system later. If you do add one, tell the installer about the kit at the quote stage, so the design and the paperwork for the network take account of everything that will be connected in the house.