United Kingdom

How the UK market works

In England, Scotland and Wales the energy regulator is Ofgem, and the same price cap, Smart Export Guarantee and grid connection rules apply across all three. Building and electrical safety rules are set separately in each nation. Northern Ireland has its own regulator and its own electricity market, so several rules on this page do not apply there (see the Northern Ireland section).

Your electricity reaches you through a regional network operator (a DNO), the company you or your installer notifies when a battery or solar system is connected. A separate supplier sells you the electricity. This split matters, because the supplier decides your tariff and export payments while the network operator decides how your battery may connect.

Electricity prices and the price cap

Ofgem sets a price cap every three months. It limits the unit rate and daily standing charge a supplier can charge on a standard variable (default) tariff. It does not limit your total bill, and it does not apply to fixed or smart tariffs. For 1 October to 31 December 2026, the Direct Debit average is 26.32p per kWh for electricity with a daily standing charge of 54.83p, and Ofgem puts a typical household using both gas and electricity at £1,723 a year (Ofgem price cap figures).

Ofgem's electricity figures do not include VAT, because domestic electricity in Great Britain is charged at 0% VAT from 1 October 2026 (HMRC Revenue and Customs Brief 10 (2026)). HMRC's brief ends the zero rate on 31 March 2027, and trade reports on the 28 October Budget say it was extended to 30 June 2027, so check HMRC before relying on an end date. Northern Ireland stays at 5%.

A battery does not reduce the standing charge. What it can change is the price of the electricity you buy: it lets you use cheap or free electricity later, at the hours when the grid is expensive. Real savings are limited by how much electricity your home uses at night and in the evening, which is why we size a battery to your own use and not to the biggest unit you can buy.

Tariffs that suit a battery

The biggest difference between a battery that pays back and one that does not is usually the tariff. Time-of-use tariffs charge less for electricity at certain hours, and a battery lets you buy at those hours and use the electricity later. Octopus Energy's Agile, Cosy and Intelligent Octopus Go are well-known examples; other suppliers have similar tariffs. Most need a smart meter, and Intelligent Octopus Go is for households with a compatible electric car or charger, so check the conditions before you plan around one.

Supplier rates change often, so treat any single price as a snapshot and compare current rates before you decide. We explain the arithmetic, including why a battery cannot save more than you use, in how home battery arbitrage works in the UK, and the tariff side in dynamic energy contracts and how to actually save.

Getting paid for exports: the Smart Export Guarantee

The Smart Export Guarantee (SEG) is the government-backed scheme that makes larger suppliers pay small-scale generators, such as households with solar panels, for electricity they send back to the grid. Suppliers with at least 150,000 domestic customers must offer at least one SEG tariff, and smaller suppliers can choose to. Rates differ a lot between suppliers, and you do not need to buy your electricity from the supplier that pays for your exports, so compare the export rate on its own.

Solar panels normally need an MCS-certified installation to qualify. A battery can help you use more of your own solar yourself, but how a supplier treats electricity exported from a battery varies, so ask before you buy. The scheme rules are on Ofgem's SEG page.

VAT on a home battery

Installing a home battery in a home is zero-rated for VAT until 31 March 2027. HMRC's VAT Notice 708/6 covers a battery installed with solar panels or other microgeneration, a battery added to an existing system, and a standalone battery that stores electricity from the grid. The zero rate for batteries has applied since 1 February 2024 and covers the whole UK, including Northern Ireland.

It is temporary. From 1 April 2027 these installations revert to the 5% reduced rate, and the 28 October 2026 Budget left that date unchanged. Which side of the date your job falls on depends on when the supply is made (the tax point), not simply when you sign, so ask your installer in writing which rate applies to your quote. The relief covers a battery supplied and installed by a contractor; buying the equipment alone is standard-rated at 20%. We walk through it in do you pay VAT on a home battery in the UK.

Loans, grants and support schemes

The newest help is a loan scheme, not a grant. The Warm Homes Loan Scheme, part of the government's Warm Homes Plan, launched at the end of October 2026. The government funds participating lenders so they can lower the interest rate on loans for solar panels, batteries and heat pumps, by up to five percentage points. The maximum loan it supports is £15,000 for a battery, and £15,000 for solar panels. You own the home you apply for (homeowners and private landlords), you apply through one of the participating lenders, not the government, and the work must be done by an MCS-certified installer. Funding is limited, normal credit checks still apply, and the lender sets the actual rate. See GOV.UK: Warm Homes Loan Scheme for the lender list and rules.

We found no UK-wide grant for a home battery on its own. In England, the Warm Homes: Local Grant, run by local councils, funds upgrades such as insulation, solar and heat pumps for eligible low-income homes with a low energy efficiency rating; ask your council whether a battery can be part of a package. ECO4, which can include a battery alongside a funded solar installation for eligible households, is due to end on 31 December 2026. In Scotland, Home Energy Scotland no longer funds solar panels or batteries for applicants who were sent an application link after 6 June 2024 (Home Energy Scotland). In Wales, the means-tested Nest scheme is the route to check.

Because schemes change quickly, check are there grants for home batteries in the UK and the linked sources before you count on any support.

Connecting a battery to the grid

A battery that can export to the grid is treated as generation, so your network operator has to know about it. The Energy Networks Association rules have two routes. Under G98 (connect and notify), a system up to 16 A per phase, which is about 3.68 kW on a single-phase supply and about 11 kW on three-phase, can be connected first and notified to the operator within 28 days. Above that you need the operator's approval before the system is connected (G99).

What counts is the rated output of the inverters on your site, not the battery capacity in kWh. A 10 kWh battery with a 3.6 kW inverter counts as 3.6 kW. This means that adding a battery to existing solar can move you from the first route to the second, unless an export limit keeps the total within the threshold. The equipment should be type-tested and listed on the Energy Networks Association's register, and most applications now go through its Connect Direct portal.

Your installer normally handles this paperwork. You can find out who your network operator is by calling 105, the free power cut line. Ask any installer which route applies and how they will handle it; our guide to choosing a battery storage installer lists the questions to ask.

Safety, wiring and building rules

Four separate sets of rules apply to a fixed home battery, and a good installer should be able to explain how the job meets each of them. The grid rules above protect the network. The wiring standard BS 7671 (the IET Wiring Regulations) covers how the battery circuit is designed, protected, labelled and tested, and recent amendments add specific requirements for battery systems. Building regulations make the electrical work a legal matter: in England and Wales, Part P covers electrical work in homes, and the work is normally signed off by an electrician registered with a competent person scheme, or checked by building control. Scotland uses its own building standards system, so ask your installer how the work will be certified there.

Fire safety is covered by PAS 63100:2024, a specification published by the British Standards Institution (BSI) in March 2024 for batteries installed in homes. It is guidance, not a legal requirement, but it is the benchmark installers are expected to follow. It favours siting a battery outside the living space, for example in a garage or an outbuilding, and where it must go indoors it expects protections such as fire separation from habitable rooms, fire detection and clear escape routes. It also calls for warning labels at the consumer unit. It covers dwellings up to 200 m² (BSI: PAS 63100:2024).

When the job is finished you should receive an electrical installation certificate, confirmation that the grid connection was notified or approved, and, in England and Wales, the building regulations compliance certificate. Keep them with your home documents: you may need them when you sell, for insurance, and for any warranty claim. We also suggest telling your home insurer and mortgage lender before installation and asking, in writing, whether the battery's location affects your cover. Outdoor units, and any home that is listed or in a conservation area, are worth checking with your local planning authority.

Plug-in solar and plug-in batteries

Since 27 August 2026 it has been legal in Great Britain to buy and use certified plug-in solar kits (SI 2026/848). The rules cover complete kits of up to 800 VA with a standard plug, one kit per home, and you should notify your network operator within 28 days. Northern Ireland is not covered.

The rules do not cover batteries. A plug-in battery that you connect to a normal socket is outside the new framework, and so is a plug-in solar kit with a battery built in. Portable power stations that you do not connect to your home wiring are a different matter and are not affected. Our comparison of plug-in and installed home batteries explains the difference in practice, and we follow the rules as they change.

Northern Ireland

Northern Ireland has its own regulator, its own network operator and a separate electricity market, so the Ofgem price cap, the Smart Export Guarantee and the plug-in solar rules described above do not apply there. Domestic electricity stays at the 5% VAT rate, while the 0% rate for installing batteries and solar does apply in Northern Ireland until 31 March 2027. Part P does not apply in Northern Ireland, so ask your installer how the work will be certified. Check with NIE Networks and the Utility Regulator for the connection process and export payments before you buy.

Outside the UK

Rules, tariffs and incentives for home batteries differ from country to country, so do not apply the figures on this page to a home elsewhere. We are adding guides for other countries to this section.

Common questions about United Kingdom