Quick Facts About Vehicle-to-Home Bidirectional Charging
- Bidirectional charging capability can replace a gas generator for powering your home during a power outage.
- An electric vehicle’s (EV’s) battery can be a tool in managing your home’s electricity costs.
- Only a handful of EVs currently have vehicle-to-home bidirectional capability.
A sometimes overlooked benefit of buying certain electric vehicles (EVs) is their vehicle-to-home (V2H) charging capability. In other words, in power-outage situations, EVs with the V2H function can supply power to a home’s electrical system.
Furthermore, they can also enable renewable energy storage, such as electricity generated by a solar panel array. However, their capability has limits, and they require some additional gear and setup.
Pro Tip: V2H charging capability is not to be confused with vehicle-to-load (V2L) capability, which can power items like electric appliances and devices. V2L doesn’t require any special infrastructure because its power delivery is via 115V outlets built into the vehicle. We provide the details of V2L in a separate article.
Here we’ll learn what is required to take advantage of an EV’s vehicle-to-home capability, highlight its benefits, and discover some of the EVs with the aptitude.
- Unidirectional Charging vs. Bidirectional Charging: What Is the Difference?
- What Are the Benefits of V2H Bidirectional Charging?
- What Are the Drawbacks of V2H Bidirectional Charging?
- What Equipment Is Required for Bidirectional Charging?
- What Vehicles Offer Vehicle-to-Home Bidirectional Charging?
- Our Take
Unidirectional Charging vs. Bidirectional Charging: What is the Difference?
Unidirectional charging has been around as long as electric vehicles. It’s the transference of AC (alternating current) from a source (the grid), converting it to DC (direct current), and use of that DC to charge an EV’s battery.
In other words, you draw power from the electrical grid to store in the EV battery. An inverter located in the EV translates the incoming AC to DC before it enters the battery. All electric cars and plug-in hybrids (PHEVs) have this capability.
Bidirectional charging simply means the current can travel from a home’s grid to the EV battery and from the EV battery back to the home’s grid. That is, the electricity can flow both ways. However, as it flows from the battery back to the grid, it must be converted from DC back to AC.
What are the Types of Bidirectional Charging?
You may hear of four types of bidirectional charging, in which energy from the EV battery streams to an external recipient. They are
- Vehicle-to-Home (V2H): As already noted, this is the path between the EV and a house or other structure, and it is the focus of this article.
- Vehicle-to-Grid (V2G): This is the path between the EV and the greater electrical grid. Primarily an energy management tool, this allows the consumer to employ the EV battery as an energy storage facility, selling energy back to the grid during peak usage hours. For example, during non-peak overnight hours, the energy is downloaded into the EV’s battery, and then that energy is fed back into the system during higher-cost daytime hours.
- Vehicle-to-Load (V2L): This is when you use energy stored in the EV battery to stream power to an electrical appliance, tool, or device. For example, illuminating lights at a campsite or powering a circular saw at a construction site.
- Vehicle-to-All (V2X): This refers to the entire bundle of V2H, V2G, and V2L schemes.
What are the Pros of Vehicle-to-Home Bidirectional Charging
There are three primary advantages of V2H bidirectional charging.
- Emergency power: Your home can lose electrical power at any time, be it wind damage, lightning striking a transformer, or some other calamity. In fact, loss of power can also result from the local power company simply being unable to supply electricity to all areas during periods of peak usage. In any event, an EV can supply enough electricity to power the average home for several hours or even days. The duration of this benefit depends on the vehicle’s battery size and the level of battery charge. V2H charging capability has the added benefit of minimizing or even eliminating gas generator use.
- Energy cost savings: Your EV’s battery can serve as a holding vessel for electricity, charging during cheaper off-peak hours and then supplying the home’s power during expensive peak hours.
- Maximizing renewable energy: Excess solar energy captured with solar panels during daylight hours can be stored in the EV’s battery and then distributed during the night when sunlight is unavailable.
RELATED: How Much Does It Cost to Charge an Electric Car?
What are the Cons of Vehicle-to-Home Bidirectional Charging?
There are two primary drawbacks of V2H charging, neither pertains to the efficiency or effectiveness of bidirectional charging.
- Cost: Introducing bidirectional charging to your home is quite expensive even before any related installation costs. For example, the required General Motors package runs more than $7,000 before installation costs and any available government tax credits.
- Availability of V2H capability: Only a handful of vehicle models currently provide V2H bidirectional charging capability. See the list below.
What Equipment is Required for Bidirectional Charging?
Taking advantage of an EV’s bidirectional charging capabilities calls for a specialized charger and other hardware requiring installation.
- Bidirectional Level 2 charger: A traditional Level 2 charger is adequate for the unidirectional charging every EV requires. However, EVs featuring bidirectional charging require a Level 2 charger engineered for streaming the current in both directions.
- Inverter: If the inverter isn’t housed inside the bidirectional Level 2 charger or the vehicle itself, a stand-alone inverter is needed to transition the DC flowing from the EV’s battery to the home into household AC.
- Transfer switch: When supplying a home with energy from an EV battery, the home system must be cut off from the external power grid. This is known as “islanding” because it creates a power island separate from the external grid. This prevents unintentional “backfeeding” current back into the external grid, which can be dangerous to workers repairing electric lines during a power outage.
- Bidirectional charging management software: When the vehicle is plugged into the bidirectional charger, the flow of current from the house to the vehicle can be automatically reversed to flow from the vehicle battery to the house. This seamless transition includes throwing the transfer switch isolating the vehicle-to-home operation from the external grid.
What Vehicles Offer Vehicle-to-Home Bidirectional Charging?
As we publish this, these are most of the common make and model 2025 electric vehicles currently offering vehicle-to-home capability.
| Make | Model |
| Cadillac | Lyriq |
| Chevrolet | |
| Ford | F-150 Lightning |
| GMC | Sierra EV |
| Mitsubishi | Outlander PHEV |
| Nissan | Leaf |
| Tesla | Cybertruck |
| Volkswagen | ID.4 |
Pro tip: More EVs featuring V2H capability are in the pipeline. Some, like the Rivian R1T and R1S, will receive the necessary technology through a software update that is in the works. It appears even models in the hands of consumers will receive the V2H capability through an over-the-air (OTA) update. Furthermore, Kia and Hyundai are working on the technology but are not ready to roll it out.
Our Take
Well-heeled tech early adopters are the most likely to go out of their way to hop on the vehicle-to-home bidirectional charging wagon. Because of the extra expense, buyers who are already jittery about going fully electric in their personal vehicle are less likely to make their buying decision based on V2H bidirectional charging.
However, for those buyers who demand the very latest technology and can afford to pay for it, V2H charging will come in handy during those rolling brownouts or occasional power outages due to storms.
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