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Powering your home from your electric car
Can you power your home from an electric car in a power cut? V2L, V2H and V2G explained, with costs and what UK set-ups allow.
By Slightly Anxious
7 October 2026 14 minute read
IN SHORT
For most households, a power station topped up from the car gives most of the benefit for a fraction of the cost. A car that can run your whole house is still a few years away.
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They can (in theory!). The technology is called bidirectional charging, and all it means is that electricity can flow out of the car as well as into it. In practice, in Britain, at the time of writing, it is a good deal fiddlier than the brochures suggest, and quite a lot more expensive. So in this article we look at what is real today, what it costs, what paperwork stands between you and a car that runs your house, and what we would do ourselves.
V2L, V2H and V2G explained
The first is V2L, which stands for vehicle to load. This simply means the car has ordinary three-pin sockets, either inside the cabin or via an adapter that plugs into the charging port, and you plug appliances into it with a lead. It works in a power cut, and plenty of cars on sale now have it, including the Hyundai IONIQ 5 and 6, the Kia EV6 and EV9, the MG4, the BYD Dolphin and Atto 3, the Renault 5 and the Volvo EX30.
What each option costs
Option
What you need
Guide Cost
V2L
A car with V2L sockets
About nothing extra
One-way home charger
Charges the car only
c.£800-£1,200
V2H charger
Bidirectional charger and installation
c.£4,000-£7,000
Island mode
Changeover switch and backup consumer unit
Add c.£1,000-£2,000
Home battery, for comparison
e.g. Tesla Powerwall 3
From about £6,000
The second is V2H, vehicle to home. Here the car feeds your house wiring directly through a special charger, so the lights, sockets and (with the right set-up) the boiler all run off the car. This is the one everybody wants. It only works in a power cut if extra isolation equipment is fitted, which installers call island mode, and at the time of writing very few combinations of car and charger are supported in the UK.
The third is V2G, vehicle to grid, where the car sells electricity back to the National Grid when it is needed and you get paid for it. The only UK household offer at the time of writing is the Octopus Power Pack, which bundles a leased BYD Dolphin with a Zaptec Pro charger and a special tariff.
The numbers
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A typical home uses about 7 kWh of electricity a day (Ofgem: 2,500 kWh a year)
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A mid-sized electric car holds about 60 kWh, with 40-45 kWh to spare for the house
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A power station charged from the car can be refilled about 40 times over
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V2L: plug appliances into the car. V2H: the car powers the house. V2G: the car sells power to the grid
The catch: island mode
Here is the bit that catches people out. A V2G set-up does nothing at all in a power cut.
Anything that feeds electricity into the network has to switch itself off the moment the network goes dead, so that an engineer mending a cable down the road is not electrocuted by your car. It is a very good rule! It does mean a V2G system will happily earn you money on an ordinary Tuesday and then sit there doing nothing in a blackout. To keep your own house running, the system first has to cut your home off from the grid and then power it on its own, and that takes extra hardware. Tesla owners, we are sorry to say that Teslas do not currently support V2H or V2G through third-party chargers in the UK.
How long could a car run a house?
So how long could a car run a house? Longer than you might think. Ofgem's figure for a typical household is now 2,500 kWh of electricity a year (it was cut from 2,700 kWh on 1 July 2026, as we are all using a bit less), which works out at roughly 7 kWh a day. A mid-sized electric car carries something like 60 kWh. Keep a fifth of that back so you can still drive somewhere if you need to, allow for a little lost in the conversion, and you have perhaps 40 to 45 kWh to spend on the house. That is about six days of normal life, and comfortably more than a week if you leave the tumble dryer alone, which lines up rather nicely with our seven-day rule. These are our own sums, not a manufacturer's promise, and your car, your house and the weather will all move the answer.
There are two big caveats. The first is heating. Our sums assume you have gas central heating. If your heating is electric, whether a heat pump or storage heaters, a cold day can use several times the average and the six days shrinks to a couple. The second is that V2L sockets are limited to roughly 2.3 to 3.6 kW at any one time. That will run a fridge, a freezer, the router, a few lamps and everybody's phone chargers together without complaint. It will run the kettle if you switch something else off first. It will not run an electric shower or an oven, so please do not try.
Remember that your gas boiler needs electricity too. Most are hard-wired into a fused spur on the wall, not plugged into a socket, so you cannot simply run a lead to it from the car. We come back to this below, and there is much more on keeping warm in our article, What to do when the heating stops.
What it costs
Now to the money. Prices in this corner of the market are moving fast and are often quoted before anyone has picked up a screwdriver, so treat the following as rough bands at the time of writing and always get proper quotes.
If your car already has V2L, the cost is more or less nothing (some cars need an adapter for the charging port, and some include one in the box). An ordinary one-way home charger, fitted, costs c.£800-£1,200, and remember that it only charges the car and sends nothing back. If you rent, or own a flat, the government's chargepoint grant will pay 75% of the cost up to £500, and it is open until 31 March 2027.
A bidirectional V2H charger with a standard installation runs to c.£4,000-£7,000. The island mode equipment that lets it keep your house running in a power cut (a changeover switch and usually a small backup consumer unit for the circuits you care about) adds c.£1,000-£2,000 on top. The best-known DC bidirectional charger, the Wallbox Quasar 2, works with the Kia EV9 and the Cupra Born 77 kWh, and early pricing suggests c.£6,000 before installation, but at the time of writing it is register-your-interest only in the UK. The Octopus Power Pack launched at under £300 a month for the car, the charger and the tariff, with free home charging included, but as we explained above it earns you money rather than keeping your lights on.
For comparison, in our article What to do when the power goes out we price a proper home battery such as a Tesla Powerwall 3 at around £6,000 upwards. A full V2H system with island mode ends up in much the same ballpark, with the small difference that the battery goes to Tesco when you do!
The paperwork
Next, the paperwork. None of this is a plug-and-play job. A bidirectional charger is treated as a small power station attached to your house, and the rules reflect that. The good news is that a decent installer handles nearly all of it for you.
Your network operator has to agree first. This is the company that runs the cables in your street (your DNO), not the company that sends you the bill. Most home V2H kit goes through what is called the G99 fast track, which gives the DNO ten working days to reply. If the system is limited so it can never send more than about 3.68 kW back to the grid, a simpler route called G98 applies and the installer just tells the DNO within 28 days of fitting. Either way, nobody should switch it on before approval comes through.
Building regulations apply too. Adding a new circuit is notifiable work in England and Wales under what is known as Part P. Use an installer registered with one of the competent person schemes (NICEIC, NAPIT, Stroma or ELECSA) and you get the certificate without ever dealing with building control yourself.
The wiring regulations (BS 7671 if you want to look them up) have a whole chapter for homes that make their own electricity. In plain English, there must be an isolating switch that can be locked off, everything must be labelled so the next electrician knows your house has two sources of power, and the earthing has to be arranged so that your safety switches still work when the house is running on the car. That last part is exactly what makes island mode a specialist job, not something any electrician can take on.
Planning permission is usually not needed. In England a wall-mounted charger counts as permitted development as long as it is no bigger than 0.2 cubic metres and is not within the grounds of a listed building or on a scheduled monument. Conservation areas can have their own restrictions, so check with your council if you live in one. The rules differ in Scotland, Wales and Northern Ireland, so check locally there too.
Check your car's warranty. Pushing power in and out of the battery every day counts as use, so get it in writing that your manufacturer is happy for your particular model to be used this way before you sign anything. Be wary of cars sold as bidirectional-ready when the feature is not yet switched on in the UK, as that is a promise, not a product. And tell your home insurer. A short phone call now beats an awkward conversation after a claim.
So what would we do?
If your car already has V2L, you have a perfectly good emergency power supply sitting on the drive today, and it cost you nothing! Find out where the sockets or the adapter are, buy a couple of decent outdoor extension leads, and keep to these rules every time.
Plug appliances into the car, never the car into the house. A lead with a plug on both ends, pushed into a wall socket to feed power back into the house, is dangerous, against the wiring regulations, and can electrocute an engineer working on the line.
Use outdoor-rated leads, unwind them fully so they do not overheat, and never plug one extension lead into another.
Keep the total load below what your car's sockets are rated for (it will be in the handbook).
Run the lead through a window or a cat flap, never trapped in a door, and keep it out of puddles.
Decide in advance what gets plugged in. Freezer and fridge first, router and lamps next, and everything else takes turns.
If you want the car to run the boiler or a few house circuits properly, ask an electrician to fit an inlet socket and a changeover switch, the same arrangement people use for generators. It disconnects the house from the grid before the car is connected, so nothing can ever reach the street.
The halfway house: a power station charged from the car
Until V2H catches up, there is a halfway house that we rather like, and it uses kit you may already own. Use the car to keep a portable power station topped up, and use the power station to run things indoors.
It works like this. The car stays on the drive and the power station does the travelling. Carry it out to the car, plug it into the V2L socket exactly as you would plug it into the wall at home, let it fill up, then carry it back inside and plug the fridge, the lamps and the router into that. When it runs low, out it goes again. Most of the larger power stations will refill from a mains-type socket in one to two hours, well within what a V2L socket can supply, so a top-up can fit around making breakfast or the evening meal.
There are several reasons to do it this way round. There is no lead trailing through a window or a cat flap all night, and nothing to trip over in the dark. The house keeps running when the car is somewhere else, so you can still drive to the shops, collect a relative, or go and find a public charger in a town that still has power. A power station gives a steady supply all night without anybody needing to go outside. And you choose when to dip into the car's battery, a little at a time, rather than letting the fridge nibble away at it around the clock.
The sums are encouraging. If we take the Jackery Explorer 1000 Plus from our article What to do when the power goes out, at about 1 kWh, a mid-sized electric car could fill it something like forty times over. You do lose a little more power doing it this way, as the electricity is converted in the car and then again in the power station (we would allow for perhaps a fifth going missing), but with a battery that size on the drive it hardly matters. A typical fridge freezer, using about 1 kWh a day, needs a top-up roughly once a day from a 1 kWh power station, or every other day from a 2 kWh one such as the EcoFlow DELTA 3 Max. Two smaller power stations work even better, as one charges at the car while the other is in use in the kitchen. The smaller units we suggest for phones and laptops, like the Anker Solix C300, can be topped up from the car in the same way.
Doing it safely
Set your car's discharge limit first. Most cars with V2L let you choose the battery level at which the sockets switch themselves off, so pick a figure that leaves you enough charge to drive somewhere useful, and leave it there.
Charge outside or in an open garage, keep the power station off wet ground, and bring it in once it is full, not left out in the rain. Check the handbook for whether the car needs to be switched on for the sockets to work, and lock it if it can be left locked while charging.
If your power station lets you choose how fast it charges, start at a lower setting. If the car's sockets cut out, that is usually the reason.
Know what you can lift. The bigger power stations weigh about as much as a full suitcase, so if carrying one to the car twice a day is a struggle, buy a smaller one, or two smaller ones, or put it on a trolley.
Do not rely on this for medical equipment. Car makers tell you not to plug equipment that needs a continuous supply into V2L, and a power station is only as good as its last top-up. If anyone in your house depends on powered medical equipment, talk to the equipment supplier about backup, and sign up for your network operator's free Priority Services Register so they know to look out for you in a power cut.
Your to do list is:
1. Check whether your car has V2L
2. Plug appliances into the car, never the car into the house
3. Use outdoor-rated leads, fully unwound
4. Decide in advance what gets plugged in: fridge and freezer first
5. Consider a power station charged from the car
6. Keep the car charged when a storm is forecast
Our verdict
If you are choosing your next car, put V2L on the must-have list. It costs little or nothing extra, and it is the only version of this technology that works in a power cut today. If V2H matters to you, check the manufacturer's own UK list of supported chargers before you buy, and do not pay extra for features that are only promised.
If you are tempted by full V2H with island mode right now, you will be an early adopter, with all that implies about price, choice of car and waiting for installers. For most households a power station topped up from the car, as we described above, gets you most of the benefit for a fraction of the cost. We would wait a year or two and let other people find the bugs.
Whatever you drive, keep it charged when a storm is forecast. A power cut takes out the public chargers along with everything else (and the petrol pumps too, for that matter), which we cover in our article Using the car in an emergency.
A car that can run your fridge is a lovely thing to have. A car that can run your whole house is still, for most of us, a few years away.
