Solar Panel Kits UK: Plug-In, Off-Grid and Battery Kits Compared

Five kinds of solar panel kit are sold in the UK: plug-in kits of up to 800 W that go into a wall socket, legal in Great Britain since 27 August 2026; hard-wired DIY grid-tie kits that need an electrician and a network operator notice; off-grid 12 V and 24 V kits for sheds, caravans and boats; power stations bundled with panels; and installed solar and battery packages. Prices observed in late 2026 ran from about £270 to over £11,000.

The word “kit” hides very different products. Some lower your electricity bill, some only power things that are not connected to the mains, and some need the same paperwork as a full rooftop installation. This guide sets out what each type contains, what it costs as of November 2026, what the rules require in Great Britain and where Northern Ireland differs, and how to size an off-grid kit with real sunshine data. Voltgeber sells nothing and does not test products; prices are observations from retailer and manufacturer pages on the dates given.

The five kit types at a glance

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The rows that feed your home wiring are the first, second and fifth. Only those reduce what you buy from your supplier. The off-grid and power station kits run devices directly and never touch the household circuits.

Plug-in solar kits

A plug-in kit is the smallest product that lowers your bill. Its microinverter converts the panels’ DC into mains-synchronised AC and feeds it into a socket circuit, where your fridge, router and anything else running at that moment use it before electricity is drawn from the grid.

Since 27 August 2026, SI 2026/848 allows these kits in England, Scotland and Wales if they meet the government’s Interim Product Specification. In practice that means:

• rated AC output of no more than 800 W and no more than 2,000 W of panels, in up to four modules with no more than two in series and no more than 120 V DC at the inverter;
• a factory-fitted, moulded BS 1363 plug, with no extension leads or adaptors;
• no battery, and no storage that draws power from the home;
• a product listed as compliant on the Energy Networks Association Type Test Register before it is sold;
• one plug-in device per household under the network rules, and a notification to your distribution network operator.

A compliant kit typically contains one to four panels, the microinverter, DC cables, the lead with its moulded plug, a mounting system with a structural analysis for UK wind and snow loads, and a label for your consumer unit. Our guide to plug-in solar kits and what’s included, with Lidl vs Aldi goes through the contents and what the two discounters have and have not announced.

An independent price check of compliant 800 W kits on 8 October 2026 found prices from about £336 for one panel to about £989 for the largest kit. The government’s July 2026 modelling estimates savings of about £70 to £110 a year for an 800 W kit, depending on orientation. To choose between kits, see how to choose a plug-in solar kit in the UK; to find sellers that list compliant models, see where to buy plug-in solar in the UK.

Northern Ireland is not covered: the amendment to the electricity safety regulations in SI 2026/848 extends only to England, Wales and Scotland, and Northern Ireland has its own regulations.

DIY grid-tie kits

A grid-tie kit is the hardware for a conventional rooftop system sold as a package: roof panels, an inverter, a mounting system and cables, sometimes a battery. It produces several kilowatts and is wired permanently into your consumer unit. That makes it a very different legal object from a plug-in kit, even though the shop page may look similar.

One UK online retailer trading as Plug In Solar illustrates the category; despite its name, its hybrid kits are hard-wired systems, not plug-in devices. On 4 November 2026 it listed:

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The listings themselves set out the catches. The retailer charges 20 % VAT on everything, because the zero rate on solar panels and batteries applies only when they are installed for you; HMRC’s guidance confirms that energy-saving materials supplied without installation are standard-rated. The larger kit needs pre-approval from your DNO under G99 before installation, which the retailer says it cannot do on your behalf. The smaller kit notes that earthing equipment is not supplied, although the IET Code of Practice for grid-connected solar PV requires it.

What a DIY grid-tie kit requires in practice:

• An electrician for the connection. The inverter connects to the consumer unit on a new circuit. In England, a new circuit is notifiable under Part P of the Building Regulations: either a registered electrician self-certifies it, or you notify building control before work starts and pay for inspection. Wales applies its own edition of Approved Document P; Scotland and Northern Ireland use their own building standards.
• The network operator. Up to 16 A per phase, about 3.68 kW on a single-phase supply, the system is notified within 28 days of commissioning under G98. Above that, G99 approval is needed before installation. A battery inverter counts towards the limit.
• Roof work. Scaffolding, a structural check of the roof and weatherproof fixing are the same as for an installed system, and planning rules for roof panels apply.
• No MCS certificate, normally. An MCS certificate is raised by an MCS-certified installer for an installation it designed and installed. Panels labelled “MCS-certified” are certified products; that does not make a self-built system a certified installation. Without the certificate, Smart Export Guarantee suppliers are not obliged to pay for exports.

After adding an electrician, scaffolding and the VAT you could have avoided, a DIY grid-tie kit often saves less than it first appears against an installed package. Our guide to solar panel installation in the UK walks through the full process and the cost data.

Off-grid kits: 12 V and 24 V

Off-grid kits power things that have no mains supply: a shed, a summer house, a caravan, a narrowboat, an allotment, a gate opener, a CCTV camera. Nothing connects to the network, so there is no DNO notice and no plug-in rule to meet.

A typical off-grid kit contains:

• Panels. Usually 12 V class rigid panels of 100 to 200 W each, around 18 to 20 V at maximum power.
• Charge controller. It protects the battery from overcharging. A PWM controller is cheap but wastes part of the panel’s voltage; an MPPT controller converts the surplus voltage into extra current and harvests more, particularly in cool weather.
• Battery. Lead-acid (AGM or gel) is cheap and heavy; lithium iron phosphate (LiFePO4) costs more, lasts many more cycles and tolerates deeper discharge. A 12 V 100 Ah LiFePO4 battery stores about 1.28 kWh.
• Inverter, optional. It turns 12 V DC into 230 V AC for mains devices. Many off-grid users run lights and chargers on 12 V directly and skip the inverter’s losses.
• Cables, fuses, connectors and brackets.

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The kits without a battery are cheaper than they look, but the battery is often the largest single cost once added.

Retailer yield claims deserve a check. Letang’s listing says its 160 W kit can deliver about 53 Ah a day on a 12 V system with an MPPT controller in summer, roughly 680 Wh. PVGIS long-term averages for Manchester give about 510 Wh a day of usable energy in June for 160 W facing south at 35 degrees, with a 25 percent allowance for controller, battery and cable losses, which is our assumption. The claim is achievable on bright days, not as an average.

Rules for off-grid wiring. A self-contained 12 V system that is not connected to the house is not covered by the network codes. Part P in England applies to fixed installations in dwellings and in outbuildings supplied from them; a shed with its own solar supply sits at the edge of that scope, and we found no official statement that settles it. Work to the wiring regulations (BS 7671) regardless, fuse every battery cable, and if you install 230 V sockets fed by an inverter, have an electrician check the earthing arrangement. If the shed already has a mains supply from the house, any connection between the two systems is work for an electrician.

Solar plus battery kits

Three quite different products are sold as solar plus battery kits.

Power station bundles. A portable lithium battery with a built-in inverter, sold with foldable or rigid panels. Nothing connects to the house. On 4 November 2026, EcoFlow’s UK site listed the DELTA 2 (1,024 Wh) with a 220 W portable panel at £898 and with a 175 W rigid panel at £698, although every DELTA 2 option, bundles included, showed as sold out. Jackery’s UK site listed the Explorer 1000 v2 (1,070 Wh) with one 100 W SolarSaga panel at £1,199, with one 200 W panel at £1,499, and with two 100 W panels and a 5 metre extension cable at £1,531. Our guide to portable solar panels explains how to match panels to a power station and what they can run in British weather.

Hybrid grid-tie kits with a battery. The DIY kits in the table above: hard-wired, needing an electrician, G98 or G99, and 20 % VAT when bought without installation.

Installed solar and battery systems. Designed and fitted by an MCS installer, with 0 % VAT on panels and battery until 31 March 2027.

What you cannot lawfully buy in Great Britain is a plug-in kit with a battery. The Interim Product Specification excludes plug-in batteries and plug-in solar kits integrated with batteries, and compliant kits must carry a warning that they are not intended for use with a battery storage system. Ofgem’s decision of 11 August 2026 notes that plug-in storage remains prohibited from sale, supply and use under the current regulations. Products designed to store solar energy and feed it back through a socket are outside the rules, whatever a listing suggests. See plug-in solar with a battery in the UK for the detail.

Installed solar and battery packages

Large installers and energy suppliers sell solar as a package: survey, design, panels, inverter, optional battery, scaffolding, installation, network notice and certificates. On its UK page viewed on 4 November 2026, Octopus Energy listed panel-only installations from £6,663, for two panels with no battery, and its most popular system, 12 panels with a 10 kWh battery, at £11,115, both based on April 2026 prices.

The government’s cost statistics give the wider market. In 2025/26 the median cost of MCS-registered installations of up to 4 kW was £1,780 per kW of declared net capacity, including VAT where charged and excluding batteries; for 4 to 10 kW it was £1,697 per kW. Installed packages cost more than a DIY kit’s hardware, but the difference buys the installation, scaffolding, certification, 0 % VAT and eligibility for export payments.

What an MCS-certified installation means for the Smart Export Guarantee

The Smart Export Guarantee (SEG) obliges licensed electricity suppliers with at least 150,000 domestic customers to offer at least one export tariff. Ofgem’s guidance for generators sets the conditions that matter for kits:

• For solar of up to 50 kW, applicants are asked for an MCS certificate; the SEG also recognises schemes that are equivalent to MCS. Without either, the supplier is not obliged to pay.
• You need a meter that records exports half-hourly and an export MPAN, in practice a smart meter.
• Tariffs must pay more than zero, but suppliers set rate and terms.
• SEG applies in Great Britain only.

Applied to the five kit types:

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Our guide to plug-in solar and the Smart Export Guarantee shows what exports from a small kit would be worth, and why the money for a plug-in kit lies in electricity used at home.

Worked example: sizing an off-grid kit for a shed

This example uses PVGIS’s off-grid calculator, which simulates a battery day by day over many years of satellite weather data. The figures are model results, not measurements.

Location. A garden shed near Manchester, panels on the roof facing south at 45 degrees. A steeper angle than for a grid-tied roof helps the low winter sun, which is when an off-grid battery struggles.

Daily use, 400 Wh. Two 10 W LED lights for three hours (60 Wh), a 10 W radio for four hours (40 Wh), charging two 18 V 5 Ah cordless tool batteries (about 180 Wh), a phone and a laptop (90 Wh) and small extras (30 Wh).

Battery. One 12 V 100 Ah LiFePO4 battery, 1,280 Wh, with PVGIS set to stop discharging at 20 percent. Usable: about 1,024 Wh, two and a half days of use with no sun.

Panels. Two options: 200 W (two 100 W panels) and 300 W.

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The pattern is clear. From April to August a 200 W kit covers 400 Wh a day almost every day, and in September nine days in ten, and in midsummer the battery is full on more than half of all days, which means surplus energy goes to waste. From November to February it falls far short. Adding 100 W of panels halves the number of empty days across the year but still leaves most winter days short. Cutting use to 250 Wh a day makes the 200 W kit reliable from March to October.

What to buy. For a hobby workshop used from spring to autumn, 200 to 300 W of panels, an MPPT controller of 20 to 30 A and a 100 Ah LiFePO4 battery fit. For year-round use with tool charging in winter, a mains supply from the house, installed by an electrician, is usually cheaper than the panel area needed, or plan to carry the battery indoors to charge it in winter.

Cable sizes in the same example

The panels sit on the shed roof, the battery and controller inside, five metres of cable away: ten metres of copper there and back. Two 100 W panels in parallel deliver about 11 A at around 19 V.

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The figures use copper’s resistivity of 0.0175 Ω·mm²/m. Four square millimetres, the common solar cable size, keeps the loss near 2.5 percent. Between battery and inverter the current is much higher: a 300 W inverter draws about 28 A from a 12 V battery at 90 percent efficiency. Keep that cable short, size it to the inverter manual (often 10 to 16 mm² or more), and fit a fuse close to the battery terminal.

How to choose a kit, step by step

Common mistakes

• Buying a grid-tie kit as if it were plug-in. Consequence: a kit you cannot lawfully connect without an electrician, a G98 or G99 notice and building control. Fix: read whether the kit has a moulded 13 A plug and an ENA compliance listing, or terminals for hard-wiring.
• Plugging an imported balcony kit into a UK socket with an adaptor. Consequence: an unlawful, non-compliant installation. Fix: buy a kit sold as compliant with the Interim Product Specification.
• Expecting SEG payments from a self-installed system. Consequence: no export income. Fix: use an MCS installer if export payments matter.
• Sizing an off-grid kit on summer output. Consequence: a flat battery from November to February. Fix: size on the worst month you intend to use the system.
• Skipping the battery fuse. Consequence: a short circuit can melt cables and start a fire. Fix: fuse every positive battery cable close to the terminal.
• Pairing a plug-in kit with a battery. Consequence: outside the rules and the product’s warning label. Fix: wait for battery rules, or install a permanently wired battery through an installer.
• Ignoring VAT. Consequence: 20 % on a DIY kit that an installer could have supplied at 0 % until 31 March 2027. Fix: get installed quotes before buying hardware.

England, Scotland, Wales and Northern Ireland

Electrical rules for plug-in kits are set for Great Britain as a whole; planning, building control and export payments are not. These are the differences that change which kit makes sense.

England

Since 27 August 2026, England’s permitted development rules name plug-in solar explicitly. On a house, panels on a wall or balcony may project up to 0.4 metres, or 0.2 metres where the wall abuts a highway, and anything on timber walls, balconies or cladding, or on a listed building, is excluded. Ground-mounted panels in a garden, including an off-grid array beside a shed, fall under a class with a 9 square metre limit and height limits near boundaries. Roof panels from a grid-tie kit or an installer may project no more than 0.2 metres from a pitched roof. Our plug-in solar planning permission guide has the full limits.

Scotland and Wales

Neither made a plug-in-specific planning change. Scotland’s Class 6HA allows solar on a dwelling projecting up to 1 metre from a wall or roof; Wales allows 20 centimetres. A vertical panel on wall brackets usually fits the Welsh limit; a tilted one often will not. Scotland uses building warrants rather than Part P; councils such as West Lothian say roof panels on a one or two-storey house need no warrant if the roof can carry them.

Northern Ireland

Plug-in kits are not covered, because SI 2026/848’s change to the electricity safety regulations does not extend to Northern Ireland, which has its own regulations. Off-grid kits, power stations and installed systems are all available. Roof panels may project up to 20 centimetres beyond a slope facing a road, and one free-standing array of up to 14 square metres and 2 metres high is allowed in a garden if it is not nearer the road than the house. The Smart Export Guarantee does not apply, so export payments depend on what NI suppliers offer voluntarily.

Durability and warranties

Rigid glass panels in grid-tie and off-grid kits often come with long product and performance warranties; check the data sheet, because terms vary. Microinverters and string inverters typically carry shorter warranties than panels. Lead-acid batteries in cheap off-grid kits may last only a few years with regular deep discharge; LiFePO4 batteries are commonly rated for thousands of cycles. Foldable panels sold with power stations carry shorter warranties; EcoFlow states five years for its portable panels. Keep receipts and data sheets with the kit, and register warranties where the manufacturer asks.

Next steps

• Plug-in solar kits: what’s included, and Lidl vs Aldi in the UK
• Solar installation in the UK: process, timeline and cost
• Where to buy plug-in solar panels in the UK