# Bidirectional charging: your car as a home battery > What V2L, V2H and V2G mean, what you can do with them today, a worked example with made-up prices and what to check before you spend any money on it. Published: 2026-05-26 · Language: en · Source: https://laadpaalvinden.be/en/blog/bidirectional-charging-v2h/ With bidirectional charging, your car takes in electricity and can also give it back out. Part of that already works. The rest depends on your car, your charger and your energy supplier. ## The variants - V2L (vehicle to load): the car powers a device through an adapter, for example a power tool, a coffee machine on a campsite or a lamp in the garden. - V2H (vehicle to home): the car supplies electricity to your house. - V2G (vehicle to grid): the car feeds electricity back into the public grid. ## What is possible today? V2L is the simplest. Some models have it built in, others need an adapter. The power is limited, though. A drill or a lamp works, a large compressor or an electric heater does not always. V2H and V2G ask for a lot more. You need a car that supports it, a compatible charger and permission or agreements with your grid operator and energy supplier. In Belgium the rules and the offering are still changing. Always check the current terms, even when a salesperson says it will be possible soon. ## A worked example All the figures below are assumptions to calculate with, not measurements from a real model. Say your car has a usable battery of 60 kWh and you set it never to drop below 50% for the house. That leaves 30 kWh at most. If your household uses 10 kWh in the evening and overnight combined, that gets you through three evenings. But you cannot use the same kWh twice. At 17 kWh per 100 km, 30 kWh is worth about 175 km. Take the electricity out of the car and there is less left to drive with. Some energy is also lost when charging and discharging. Assume you lose 10%. Of 12 kWh of surplus solar power that you put into the car during the day, you get 10.8 kWh back in the evening. The real loss depends on the equipment. ## Does it pay off? With a dynamic contract you buy electricity cheaply and use it when the price is high. Take made-up prices: 10 cents per kWh at night and 30 cents per kWh in the evening. With 10% loss, 1 kWh from the car costs you 0.10 / 0.9 = about 11 cents. So you save around 19 cents per kWh. At 10 kWh an evening, that is almost 2 euros. If you have solar panels, you compare two other prices: what you get for electricity you put on the grid and what you pay in the evening to take electricity from it. If the gap is big, the car is a way to make use of it. If it is small, you gain little. Those prices change with your contract and with the rules, so calculate with your own figures. There is also a cost that does not show up on your bill. If you take 10 kWh out of a 60 kWh battery every evening, after six days that is as much electricity as one extra full charge going through the battery. How much wear that causes, and what the warranty says about it, is something to ask the manufacturer. ## Getting through a power cut Say your home draws 0.5 kW on average during a power cut for the fridge, lights and router. With 30 kWh available, that lasts 60 hours in theory. Switch on the hob or the heat pump and it drops far faster. This only works if the system can explicitly run in backup mode. Many setups simply switch off during an outage, for safety reasons. Ask about it before you buy. ## What to do beforehand 1. Ask the manufacturer whether your exact model and trim supports V2H or V2G, and with which charger and software. 2. Ask in writing whether the warranty covers this use. 3. Ask your grid operator and supplier whether feeding back to your home or the grid is allowed and how it is paid. 4. Have an installer quote for the compatible charger, including inspection. 5. Set a lower limit in the software so the car never drains itself before you need to leave. ## Common mistakes - Buying a car for V2H while the charger, contract or regulations are not ready yet. - Forgetting that the car may be away during the day. If it is parked at the office, it does not take in solar power at home. - Assuming the lights stay on automatically in a power cut. See above. - Setting off on a long drive with a battery you drained overnight. ## Who is it not for? If you have no parking space or driveway of your own, V2H is off the table. If you drive a lot, the car has little electricity left over for the house. And if you simply want to store your solar power, a home battery is often simpler, because it stays at home and does not drive off. You can read about the difference in [home battery and EV](/en/blog/home-battery-and-ev-combo/). Want to use solar power without bidirectional charging? Read [charging with solar panels](/en/blog/charge-ev-with-solar-panels/).