Vehicle-to-Grid and Vehicle-to-Home Charging in the UK

Two-way charging turns an electric car from a pure consumer of electricity into a store of it. Vehicle-to-grid technology, usually shortened to V2G, allows an EV charger to not only charge a vehicle but also take energy from it¹. In practice that means the battery sitting on your driveway can sell electricity back to the grid when prices are high, power your own home when you would rather not buy from the network, or both. The Climate Change Committee describes the whole family of these technologies, V2X, as allowing electric vehicles to operate bidirectionally: charging from the electricity grid but also discharging to the grid, a building or the home as needed².

The prize is real but the market is young. The UK's largest domestic trial, Project Sciurus, found customers could earn as much as £725 a year without doing anything except keep their car plugged in, though typical figures are lower and the hardware still carries a substantial premium over an ordinary smart charger³. This page explains what V2G, V2H, V2B and V2L each mean, what equipment a household needs, what the trials actually found, what the earnings and costs look like, where the safety standards stand, and what two-way charging genuinely does for a home's energy independence, and what it does not.

How vehicle to grid, home, building and load differ

The umbrella term is bidirectional charging: energy flows both ways between the car and the outside world. A V2G enabled chargepoint is able to draw power to charge the vehicle and export the electricity from the car battery back to the home or the grid⁷. Cenex, the not-for-profit research body that has run most of the UK's V2G trials, describes V2G chargepoints as providing bi-directional flows of energy and data between a plug-in electric vehicle and the grid, enabling EV batteries to charge, store and discharge electricity when prompted⁸. The Welsh Government's national standards put it in network terms: V2G refers to the use of vehicle batteries as storage to help balance supply and demand on the electricity network, applying at scales from individual batteries up to aggregation of multiple batteries across one or more carparks⁹.

Within that family, four labels matter to a householder:

• V2G (vehicle-to-grid): electricity flows from the car back to the public network, usually to earn money or provide a service to the grid operator.
• V2H (vehicle-to-home): electricity flows from the car into your own house, powering your own circuits rather than the network.
• V2B (vehicle-to-building): the same idea at the scale of a block of flats, an office or a carpark, where many vehicles serve one building.
• V2L (vehicle-to-load): the simplest form, running an appliance directly from a socket on the car itself, with no charger in the loop.

The distinction is not just labelling, because each route needs different equipment and different permissions. V2L needs nothing more than the car. V2H needs a bidirectional chargepoint wired into the house's own circuits. V2G needs all of that plus a relationship with an energy supplier or aggregator who can actually pay for the exported electricity. Energy Saving Trust frames the prize at national scale: having electric vehicles as battery storage will allow us to better manage the UK's energy¹. Cenex lists the household-level uses as demand shifting to reduce electricity costs, supplying energy to energy markets, and increasing the use of localised renewables¹⁰.

Kit required for a typical home setup

The core requirement is stated plainly in the government's guidance on registering energy devices: V2G requires a bi-directional chargepoint and for the car to be V2G compatible⁷. Both halves must match. A bidirectional charger cannot pull power from a car that was not designed to export through its charging port, and a capable car cannot export through a one-way charger.

On the car side, common V2G-ready vehicles include the Nissan Leaf and the VW ID Buzz¹¹. On the charger side, Cenex reported four V2G charger models available in the UK through different suppliers as of January 2021, with new suppliers entering the market regularly¹². Eligibility for the tariff and trial products built around V2G usually also requires a smart meter, and V2G is still not widely available¹¹.

The installation itself is a step up from a standard home charger. Under the building rules that apply to EV charging equipment, a charge point must be a minimum of a Mode 3 specialised system running from a dedicated circuit, or equivalent, as defined in BS EN IEC 61851-1, meet the requirements of BS 7671, and follow the IET's Code of Practice for EV charging equipment installation¹³. Cable routes must meet BS 7671, BS 8300-1 and the same IET Code of Practice¹³. The cost of connecting a charge point to the grid can be substantial: the requirement to install one in a new residential building is exempted if the additional cost of the electricity grid connection exceeds £2,000¹⁴, a threshold confirmed in the Scottish building standards consultation¹⁵. For context on how modest the baseline is, the cost of meeting domestic compliance guide requirements was put at £53 in 2015¹⁶.

Two practical points follow. First, a V2G unit acts and looks very similar to a standard charging point¹⁰, so the visual disruption to a home is small; the difference is inside the unit and in the paperwork. Second, the quality of the equipment matters more, not less, when power flows outwards as well as inwards. Electrical Safety First has recalled a WAI wall-plugging charger for electric vehicles, black and white in appearance, carrying a fire risk and failing to meet the requirements of the Electrical Equipment (Safety) Regulations 2016¹⁷. A household buying bidirectional equipment is buying a device that will be energising its own home wiring, so certification is covered in detail under EV charge point safety, standards and certification, and the installation process under home EV charge point installation.

Results from the trials

The UK has run more domestic V2G trials than anywhere else, and the findings are unusually concrete because they come from real homes rather than simulations.

Project Sciurus was the largest. It started in April 2018 with OVO Energy, Cenex, Nissan and Indra, and ran for three years, from 2018 to 2021¹⁸. The original ambition was to develop, build and install 1,000 domestic V2G units; the target was reduced to between 300 and 400, and the trial ended with 325 V2G units in real homes across the UK¹². Data was analysed over twelve months, between January 2020 and December 2020¹⁸. Across the programme, over 750 MWh of energy was offset through V2G¹⁸, and customers exported energy back to the grid during peak times in exchange for over three million "free" miles³.

V2G Britain (V2GB) was the feasibility study that sat alongside the trials, funded by the Office for Low Emission Vehicles (OLEV) and the Department for Business, Energy and Industrial Strategy (BEIS), with a consortium of Nissan, Energy Systems Catapult, Cenex, Moixa, Western Power Distribution, National Grid ESO and Element Energy²⁰. Cenex identified 24 potential value streams for V2G, shortlisting LV and HV DUoS charge avoidance, DTU, imbalance management, FFR (dynamic and static), STOR Flexible and energy price arbitrage²⁰. It also built 16 domestic customer archetypes and 18 commercial archetypes to work out who V2G actually suits²¹.

E-Flex was the first project in Great Britain to demonstrate EVs performing grid services¹⁹. Across the wider programme, 330 V2G devices were installed across the UK³.

The consistent lesson from all of them is that value depends on behaviour. A car parked and plugged in for most of the day can earn far more than one that leaves at seven in the morning and returns at seven in the evening. V2GB's modelling captured this with plug-in rate scenarios: a 7kW V2G charger could achieve annual revenues of around £436 above smart charging for a high plug-in rate archetype of 75%²⁰. The same study found that when grid services are included, smart charging alone captures 40% of the total value of V2G for low plug-in scenarios, or merely 10% for high plug-in cases²⁰, which is why the two technologies are compared directly on our page on V2G vs smart charging.

£150 to £725 a year: what shapes your income

The headline numbers from the trials span a wide range, and it is worth being precise about where each figure comes from.

The top figure, £725 a year, comes from customers in the trial who were able to earn that much without needing to do anything except keep their car plugged in³. The same trial found that V2G technology could save customers £340 compared with £120 when using one-way smart charging⁴. Cenex's later work narrows the everyday expectation: average UK revenue generation from V2G is estimated at £150 to £200 per year⁵. The spread is driven by three things: how long the car is plugged in, whether the charger is enrolled in grid services, and the shape of the household's tariff.

There is also a value that never reaches the household's bank account but does reach its bills indirectly. Research cited by Ofgem has shown V2G has the potential to save £3.5bn per year in areas such as grid infrastructure reinforcement, storage and generation³. Cenex estimates V2G could defer network upgrades of £5bn, or £180 per household⁵, could help save £200m of cumulative distribution network investment by 2030²¹, and could save an additional £40 to £90M annually in GB by 2030²¹. At national scale, the Electricity System Operator estimates that in 2050, vehicle to grid, "batteries on wheels", could offset as much as 85% of the residual EV demand that remains in peak periods after smart charging has shifted the majority of EV demand outside peak hours²². Reduced renewable curtailment could amount to a saving of 6 MtCO2e per year⁵.

For comparison, households that already export electricity do so at modest scale: during the June 2026 heatwave week, British homes with solar panels sold 4.6kWh of electricity back to the grid per household per day, earning 55p²³, and Feed-in Tariff export payments across the scheme totalled around £78.4 million in scheme year 14²⁴. V2G earnings sit on top of that export landscape rather than replacing it, and the detailed figures are broken down on our page on V2G earnings.

The extra cost and how soon it is recouped

The cost question is the reason V2G is not yet mainstream. By the end of the Project Sciurus trial, the V2G hardware and installation cost was around £3,700 higher than that of a smart, one-directional chargepoint⁴. Cenex's commercial viability study estimated the premium for a V2G charger above a smart charger at around £4,000 in 2021¹².

Against average earnings of £150 to £200 a year, that premium is a long payback. The trials themselves drew the conclusion: analysis from V2G trials suggests the V2G premium would need to be less than £2,000 for the technology to be acceptable to the mass market⁶. A cost of around £1,000 would mean the payback period for V2G could comfortably be below five years for those on tariff optimisation alone⁴.

The direction of travel is downward, on three separate projections:

• Cenex predicts V2G charger cost to fall to £1,000 by 2030⁵.
• The V2G Britain report suggests the premium over an equivalent smart charger is expected to reduce to between £656 and £1,164 by 2030⁶.
• If the price of V2G hardware comes down on a similar trajectory to how domestic solar PV has come down, V2G units would carry a £1,000 premium above a smart charger in about seven years⁸.

Cenex also predicts V2G hardware prices will fall below the £3,000 to £5,000 level by 2025⁵. One further number belongs in the ledger on the benefit side: Cenex reports an annual depreciation saving of £230, on a 10-year asset depreciation period, because managed cycling extends battery life⁵. The full cost picture, including what a household actually pays today, is set out on our page on V2G charger cost.

Progress on the standards

Bidirectional charging is a safety-critical technology: it back-feeds a home's wiring and, in the V2G case, the public network. The governing international standard is IEC 61851-23:2023, edition 2.0, published on 13 December 2023 by technical committee TC 69, Electrical power/energy transfer systems for electrically propelled road vehicles and industrial trucks²⁵. It is classified as a safety standard and applies to the EV supply equipment that provides energy transfer between the supply network and electric vehicles²⁵.

The 2023 edition is the one that brought bidirectional power transfer into scope. It specifies EV supply equipment of system A, system B and system C, and provides the requirements for bidirectional power transfer (BPT) EV supply equipment for system A, with a rated maximum voltage at side A of up to 1,000 V AC or 1,500 V DC, and side B up to 1,500 V DC²⁵. The requirements for reverse power transfer and bidirectional power transfer for systems B and C are under consideration and are not specified in the document²⁵, with a stability date of 2026²⁵.

In the UK, the practical rules for any domestic charge point apply with full force: the Mode 3 dedicated circuit, BS 7671 and the IET Code of Practice requirements described earlier¹³. The context is a fast-growing network: as of 1 July 2025 there were 121.3 public charging devices per 100,000 population across the UK, including 7,803 en route charging devices²⁶. The safety case is not theoretical. The recalled WAI wall-plugging charger, which failed the Electrical Equipment (Safety) Regulations 2016 and carried a fire risk¹⁷, is a reminder that uncertified equipment in this space is dangerous even when it only charges. Equipment that exports as well is covered by the same discipline, and the wider framework is explained on our page on EV charge point safety, standards and certification.

V2G and self sufficiency: the reality

For a household's energy independence, V2H is the more interesting half of the family, because it is the half that works when the grid does not. A car battery is large by domestic standards: the average battery electric car now drives almost 300 miles on a single charge, which implies a store that can run a house for days rather than hours. With V2H, that store can power the home during an expensive peak period, or hold a household over a supply interruption. Whether an EV can genuinely act as whole-house backup, and for how long, is covered in detail on our page can an electric car power my house.

Paired with solar, the loop closes further. Cenex found that storing generation from a 4 kWp domestic solar PV system in an EV battery over a weekend with 6 hours of sun per day could save over 600 kgCO2e per year⁵. In the V2GB modelling, the strongest case, £278 net annual revenue per BEV, was customers with solar and high plug-in rates in a constrained area²⁰. Toyota's expansion of its charging ecosystem across the UK, announced in December 2025, will allow EVs to not only draw energy from the grid but also return it when needed, with more advanced solutions including V2G integration planned as collaborations expand to additional countries²⁷.

The limits deserve equal weight. V2G in the strict sense increases a household's engagement with the grid rather than reducing it: the earnings come from selling to the network, through a supplier or aggregator, on terms that company sets. The household remains dependent on that intermediary, on the tariff structure, and on the charger manufacturer's platform. V2G is still not widely available¹¹, and Cenex's assessment is that the technology is only likely to achieve commercial readiness and mass rollout in the UK between 2030 and 2035²⁸. The UK and France are currently the lead markets for V2G, with strong emerging opportunities in Germany, Japan, Canada, the USA and China⁶.

There is also a resilience argument that sits above any single household. Cenex has set out how V2G could mitigate future winter blackouts, noting that up to 450 kg of emitted carbon dioxide or £400 could be saved per vehicle each year with careful managing of charging and discharging²⁸. The system operator's 2050 estimate, that V2G could offset as much as 85% of residual peak EV demand²², means a household that participates is helping the national system absorb EV growth without building as much new generation. Energy Saving Trust's summary holds at both scales: having electric vehicles as battery storage will allow us to better manage the UK's energy¹.

The honest position for a householder today is this: two-way charging is proven, safe when certified equipment is properly installed, and capable of meaningful earnings and genuine backup power, but it is still an early-adopter purchase at a premium of thousands of pounds. The trajectory of the costs, the standards and the market all point one way, and the pages on V2G earnings, V2G charger cost and EV charging and household energy independence carry the detail.