Four sets of rules, and only one of them is local.

Ring one, the United Kingdom

What the device is allowed to be

This layer does not care where you live. It fixes what may be sold and what it may do, and it took effect on 27 August 2026 under SI 2026/848.

• 800 VAMaximum apparent power to the mains. The instrument separately puts rated AC output at 800 watts, which is a different quantity
• 3.5 AMaximum current
• 2000 WMaximum total DC power of the panels, feeding that 800 VA inverter
• 960 WAbove this much panel capacity the manufacturer must advise a professional assessment of your wiring
• Four modulesMaximum per inverter, and no more than two in series in any one string
• IP55Minimum rating for a socket sitting outside the building
• No batteriesStorage, alone or built into a kit, sits outside the approved class
• No extension leadsExtension cables, multi-way adaptors, RCD adaptors and travel adaptors are all ruled out in terms

Decided by: Parliament, and DESNZ through the interim product specification

Ring two, England

Where you are allowed to put it

Planning is devolved, so this ring stops at the border. The English permitted development right was rewritten on the same day the product arrived, and it now names plug-in solar directly in order to exclude one surface.

• TimberA wooden wall, a balcony or timber cladding is not covered, for houses or for blocks of flats
• Pitched roofBelow the ridge, projecting no more than 200 mm
• Flat roofNo more than 600 mm above the roof
• WallsUp to 200 mm proud where the wall abuts a highway, 400 mm elsewhere
• Conservation areasNothing on a highway-fronting wall in a conservation area or a World Heritage Site
• ListedExcluded in the grounds of a listed building or on a scheduled monument, and a listed building needs consent as well as permission
• Until Aug 2027A transitional year in which the previous conditions may be used instead

Decided by: your local planning authority, under English permitted development

Ring three, the licence area

Who you have to tell, and when

Connection is handled by whichever company holds the distribution licence where you live. For most of this region our working map says that is National Grid Electricity Distribution (South West) plc, and the bracket in that name is doing more work than it looks.

Anyone who would rather ask than read can reach their own operator on 105, free, from any phone in Great Britain.

• 28 daysThe window for telling them, counted from installation rather than from purchase
• Three fieldsYour name, an email address, and the address the device is installed at
• 5 to 10 minThe department's own estimate of how long the form takes
• One deviceThe connection rules cap a household at a single unit, which is tighter than the product spec
• No feeNothing is charged and no inspection follows

Decided by: the distribution network operator, under Engineering Recommendation G98

Ring four, your address

The ring we cannot fill in

Everything above is public and we have read all of it. What decides your answer is none of it. It is which way the wall faces, what stands between the panel and the southern sky for four hours in the afternoon, what the wall is actually built from under the paint, and whether the deeds on your house say anything about fixings.

Send us the postcode and what you can see, and we will fill in the outer three rings for your address specifically and tell you plainly which parts of the fourth one only you can answer.