Plug-in solar for flats, balconies and renters

Why a flat is actually a good candidate

Most of the cost and complexity of conventional solar is the roof: scaffolding, a roofer, a structural opinion, an MCS-certified installer and a system you cannot take with you. A plug-in device removes all of that. It needs a balustrade, a wall bracket or a few square metres of terrace, and a socket.

The scale suits a flat too. The compliant devices reaching the market are one or two panels. A single 460 W panel is roughly the footprint of a door. An 890 W pair will occupy most of a typical balcony balustrade but not more than it. And because the device plugs in rather than being wired in, it is portable in a way roof solar never is, which matters when the average tenancy is short and the average leasehold flat changes hands sooner than a house.

The counterweight is generation. A balcony rarely offers the orientation or the tilt that a roof does, and the published output figures assume the roof case. That is dealt with below, but it is worth knowing before you read any manufacturer’s headline number.

What is actually legal from 27 August 2026

The Plug-in Solar Devices legislation, SI 2026/848, legalises a deliberately narrow category. To fall inside it, a device must be:

• Battery-free. The DESNZ proposals relate only to plug-in solar devices without batteries.
• Rated at no more than 800 VA / 800 W AC. The DESNZ Interim Product Specification expresses this as 800 VA apparent power measured as a ten-minute average. The statutory instrument text says 800 watts.
• Limited to 3.5 A AC output and 2,000 W of PV DC input.
• Fitted with a non-rewireable moulded BS 1363 plug carrying a BS 1362 fuse of 5 A or less.
• Registered on the ENA Connect Direct database before it is placed on the market.

Two consequences matter more in a flat than anywhere else. First, adaptors, convertors and extension leads are prohibited. A great deal of balcony solar hardware is designed for the German market and terminates in a Schuko plug, and that lead cannot lawfully be adapted for use here. Second, where the plug and socket assembly is outdoors (which on a balcony it very often is) it must be rated to at least IP55. If the only socket within reach is an indoor one, the cable route through a door or window becomes part of your application to the freeholder.

Territory matters as well. The plug requirement applies UK-wide. The connection limb applies in Great Britain only. The permitted development change discussed below is England only. Our guide to the legal rules sets the whole framework out.

Is the balcony yours? The demise question

This is the question that decides most applications, and almost nobody asks it first. The Property Institute, the trade body for residential managing agents, advises that whether a balcony is demised to the leaseholder or forms part of the common parts is usually decisive.

There are three common arrangements, and your lease will tell you which one you have:

• Fully demised. The balcony, including its balustrade, forms part of your demise. You still have to comply with the covenants, but you are fixing hardware to something you hold.
• Partly demised. The floor surface is demised. The balustrade, the soffit and the external face of the building are retained by the freeholder. This is very common and it is the awkward case, because the balustrade is exactly what you want to clamp a panel to.
• Not demised. You have a right of exclusive use over an area that remains common parts. Everything you attach is attached to someone else’s property.

How to read the lease without a solicitor:

• Find the parcels clause and the lease plan. The plan is usually decisive on extent. Look at whether the balcony is inside the red or blue edging and whether the balustrade line is included.
• Read the alterations covenant. Most leases prohibit alterations to the exterior absolutely, or permit them only with the landlord’s prior written consent. Where consent is required, it is often qualified so that it may not be unreasonably withheld, which gives you something to work with.
• Read the covenants on external appearance, obstruction of balconies, nuisance and annoyance and insurance. An insurance covenant that prohibits anything which vitiates the block policy is common and is a genuine constraint.
• Check whether there is a regulations schedule the freeholder may vary. Many blocks already ban satellite dishes, washing lines and awnings on balconies, and a panel will be read against that list.

Writing to the freeholder or managing agent

Treat it as a licence-to-alter application rather than a request for a favour. A short, specific letter that answers the questions an agent has to answer anyway will get a decision faster than an enthusiastic one. Include:

• The exact product, its AC rating, and confirmation that it is registered on the ENA Connect Direct database as compliant.
• The mounting method and how load is transferred: clamps to the balustrade, a ballasted frame on the floor, or a wall bracket. Say explicitly whether anything is drilled.
• Weight and the projected wind loading, with the manufacturer’s figures. This is the point agents care most about.
• Whether the panel projects beyond the balustrade line, and if so by how much.
• The IP rating of the outdoor plug and socket assembly, and the cable route.
• Your G98 notification commitment and the fact that no electrician is involved because the device connects to an existing socket.
• Reversibility: an undertaking to remove the device and make good on request or at the end of the lease or tenancy.
• Insurance: confirmation that you have told your contents insurer and an offer to provide evidence of liability cover.

Expect them to ask about, and to weigh, the following:

• Falling from height. A panel on a balustrade six floors up is the risk that dominates the agent’s thinking, and reasonably so.
• Fire and electrical safety, particularly on escape routes and on external walls.
• External wall remediation. The Property Institute singles out buildings awaiting remediation as a particular concern. If your block has an outstanding EWS or remediation programme, expect a refusal, and expect it to hold. Attaching anything to an external wall that is due to be stripped and rebuilt creates obvious problems for the works, the warranty and the insurer.
• Uniformity and precedent. Whatever they permit for you, they will have to permit for the whole block.
• The block insurance policy. Freeholders routinely have to notify insurers of alterations, and an insurer’s position on balcony-mounted electrical equipment may not yet exist.

If you rent, your landlord may need to make this same application upwards before they can answer you. Build that into your timetable.

Planning: the England-only position for blocks of flats

SI 2026/896 amends permitted development rights in England only, from 27 August 2026. For a block of flats, the right does not apply:

• on a listed building, which has no permitted development right for this at all,
• on a wooden wall, balcony or enclosure, or
• on any part of the exterior of a block of flats which is clad in timber.

Conservation areas and World Heritage Sites are restricted where the installation would front a highway. There is a transitional provision: development permitted before 27 August 2026 may continue until 26 August 2027.

Outside England, no Scottish or Welsh equivalent has been located. The planning position in Scotland and Wales is therefore unconfirmed rather than permissive, and you should not assume the English right reads across.

Orientation, vertical mounting and what they cost you

The generation figures quoted for plug-in solar describe a south-facing array at a sensible tilt. On that basis, for central England, PVGIS gives roughly:

A balcony installation rarely achieves that. A panel mounted vertically on a south-facing balustrade generates materially less than the same panel tilted towards the sun, because it is presenting its face to the wrong angle for most of the day and for most of the year. An east or west facing balcony gives up more again, and a north-facing one is not worth the application letter.

A single derating percentage would be misleading, because the figure depends on your latitude, the exact mounting angle and what is in the way. The output in the table is the ceiling for a flat rather than the expectation. If you have floor space on a terrace and can tilt a panel on a ballasted frame rather than clamping it flat to a railing, take it.

Two shading traps specific to flats:

• The balcony above yours shades the top of a vertically mounted panel for much of the middle of the day in summer, which is when the sun is worth most.
• Glass or perforated balustrades and the building’s own reveals produce partial shading, and partial shading on a small array costs proportionally more than it does on a roof.

One device per household, and how your flat is metered

Under G98 Issue 2 Amendment 1 (2026), the limit is one device per household. The intended move to one device per circuit requires a further G98 amendment which has not been made, so do not plan around it.

In a block this is worth a moment’s thought before you buy. The household boundary here is defined by the electricity connection, not by your front door. If your flat has its own meter and its own MPAN, you are a household in the ordinary sense. If the block operates a shared or landlord supply, a heat network with a communal electrical arrangement, or sub-metering behind a single connection, then the position is less obvious and it is worth asking the managing agent and your supplier how the flat is connected before you commit to hardware.

The G98 notification, including when you leave

There is no small-system exemption. Notification is required. The mechanism is:

• Connect the device.
• Notify your distribution network operator no later than 28 days after commissioning, using the Appendix 3 Form B under Engineering Recommendation G98.
• Notify again on disconnection.

It is connect-then-notify, which is a genuine simplification, but it is not optional and the second half is the half people forget. In a flat you are unusually likely to trigger it: a plug-in device is portable, and when you move you will take it with you. Send the disconnection notification then, and a fresh Form B at the new address. Your distribution network operator is set by geography rather than by who supplies your electricity. The Energy Networks Association can tell you which one is yours.

What you will actually save in a flat

The government’s estimate is £70 to £110 a year for an 800 W system, on a price assumption of £400 to £600 for a complete system, central case £500. MoneySavingExpert gives a payback of four to six years on that basis.

The prices actually being asked at launch are higher than that assumption. No Amazon-listed kit has a confirmed entry on the ENA Connect Direct register yet, so before you buy, ask the seller for the register reference for the exact model.

What decides your saving is self-consumption, the share of what you generate that you use in the moment. For a household out all day with no storage that is roughly 30 to 35 per cent. For someone at home during the day it is roughly 70 to 90 per cent. At about 25p per kWh, an 800 W array therefore saves something like £50 to £60 a year at the low end and £150 to £190 at the high end. Derate again for a vertical or off-south balcony.

A battery would lift self-consumption from about a third to about three-quarters and roughly double the saving. It also takes you outside the plug-in framework entirely: batteries are expressly excluded, so a battery system needs an electrician and a G98 notification in the conventional way, and typically costs a few hundred pounds more in installation. Battery storage remains perfectly legal, but it falls outside the plug-in category. In a leasehold flat it is also a much larger consent conversation.

No grant, subsidy or VAT scheme specific to plug-in solar has been identified. If a retailer tells you otherwise, ask them to name the scheme.

Whether that arithmetic works for you is the subject of our payback guide, which works the numbers at the prices actually being charged rather than the prices the government assumed.

A realistic order of operations

• Read the lease or tenancy first. Establish whether the balcony and its balustrade are demised to you. This costs nothing and can end the project in ten minutes.
• Check the building. If it is awaiting external wall remediation or is listed, stop there.
• Apply in writing to the landlord, freeholder or managing agent, with the detail listed above.
• Check the planning position if you are in a conservation area or a World Heritage Site, or if the panel would project beyond the balustrade.
• Buy only a device you can find on the ENA Connect Direct register as compliant, with a moulded BS 1363 plug and no adaptor in the box.
• Install, then notify your DNO within 28 days on Form B.
• Tell your contents insurer, and keep the consent letter with your lease papers.
• Notify disconnection when you move, and start again at the new address.