One of the most talked about features in the EV world works only when your car is parked: Bidirectional charging allows owners to turn their vehicles into four-wheeled batteries, sending power back to their homes, appliances and even to the utility grid.
Currently, bidirectional charging is available in only a handful of cars, including the Ford F-150 Lightning and the Nissan Leaf. But its popularity is growing: In August, GM announced that the technology will come standard in all its electric vehicles by model year 2026.
And while Elon Musk has downplayed the technology as "inconvenient," Tesla confirmed that all of its models will support bidirectional charging functionality by 2025.
In California, legislation requiring bidirectionality as a standard feature in all EVs sold in the state already cleared the Senate and is being considered by the House.
"EVs are energy storage on wheels," the bill's sponsor, State Sen. Nancy Skinner, said in May. "Why waste that battery, given how few miles most people use the vehicle in any given day? But we need to make it as easy as possible."
Here's what you need to know about bidirectional charging, including how it works, which cars have it and whether it's the next big thing in energy storage.
For more, check out the best EVs on the road today and find out where you can charge your EV for free.
What is bidirectional charging?
Typically, EV charging is a one-way process: Alternating current (AC) electricity -- the kind that comes from a wall socket -- is sent from an EV charger, outlet or other power source to a car's battery, where it's converted into direct current (DC) energy.
But bidirectional charging allows the vehicle to convert stored DC energy back into AC electricity for a variety of uses.
How can I use bidirectional charging?
Depending on the setup, the power stored in the battery can be used in different ways:
Vehicle to home (V2H): Also known as vehicle to building (V2B),this functionality allows your car to serve as a backup generator during a power outage. A fully charged EV battery holds about 60 kilowatt-hours of electricity on average, enough to power a home for two days.
With smart-charging technology, you could also use V2H tech to lower your energy bill by charging your EV during off-peak hours and powering your home when prices are higher.
Vehicle to grid (V2G): A vehicle with V2G charging capability can send electricity back to the utility network, just like homeowners with solar power can do. Not only are you helping stabilize the grid, you get paid for the energy you provide.
An EV owner with a V2G charger could save up to $150 per year on their electricity bill, according to data from the University of Rochester.
Vehicle to load (V2L): The most basic type of bidirectional charging. Typically, an adapter is all you need for your car to power camping equipment, power tools, home appliances or other standalone devices.
Vehicle to vehicle (V2V): Another form of V2L, this allows EV owners to provide power to an EV that's run out -- similar to giving a "jump" to a gas-powered automobile.
Vehicle to everything (V2X): An umbrella term that encompasses all bidirectional charging options.
Which EVs offer bidirectional charging?
Only a limited number of EVs sold in the US offer any form of bidirectional charging. They include:
- Ford F-150 Lightning (V2G)
- Genesis GV60 (V2L)
- Hyundai Ioniq 5 (V2L)
- Hyundai Ioniq 6 (V2L)
- Kia EV6 (V2L)
- Kia Niro (V2L)
- Mitsubishi Outlander PHEV (V2L)
- Nissan Leaf (V2H, V2G)
- VW ID.4 (V2H)
When will bidirectional charging become standard?
While bidirectional functionality is by no means universal, automakers are swiftly adding it to their lineups to meet demand and, potentially, get ahead of regulators.
BMW, Volvo and Porsche are all reportedly testing functionality. Tesla has said all of its models will support bidirectionality by 2025.
General Motors will make V2H charging a default feature starting with the 2024 Chevrolet Silverado EV RST. The GM rollout will continue with the 2024 GMC Sierra EV Denali Edition 1, 2024 Chevrolet Blazer EV, the 2024 Chevrolet Equinox EV, the 2024 Cadillac Lyriq and the 2025 Escalade IQ, Cadillac's first full-size all-electric SUV.
Making bidirectionality standard "will help accelerate GM's vision of an all-electric future," GM Energy Vice President Wade Sheffer said in a statement.