V2G vs V2H vs V2B vs V2X: what is the difference?
Compare V2G, V2H, V2B and V2X by where EV battery energy goes, what each use case can do and what a working bidirectional system requires.
V2G vs V2H vs V2B vs V2X: what is the difference?
The main difference is where energy from the EV battery goes. V2G exports to the public grid, V2H supplies a home and V2B supplies a larger building or site. V2X is the umbrella term covering all of these bidirectional energy uses.
The UK electric vehicle smart charging action plan uses the same distinction: the “X” in V2X can be a home, building or the electricity grid.
What is V2G?
Vehicle-to-grid sends electricity across the site boundary to the public network. An energy supplier, aggregator or flexibility provider normally coordinates when participating vehicles charge and discharge.
V2G can support grid balancing or provide value through an energy or flexibility service, but payment is not automatic. The vehicle owner also needs an eligible service, suitable metering, an export arrangement and any required network approval.
What is V2H?
Vehicle-to-home uses the EV battery behind the meter to supply one household. It can reduce grid imports during expensive periods, increase the use of stored solar energy or provide backup power.
Backup is a separate capability. The installation must be able to disconnect safely from the public network and control which circuits remain powered. A charger described as bidirectional does not necessarily provide whole-home backup.
What is V2B?
Vehicle-to-building applies the same principle to a workplace, depot, apartment building or other commercial site. One vehicle or an aggregated fleet could reduce peak demand, support local solar use or supply selected loads.
V2B usually needs coordination with a building or energy-management system. Vehicle availability and operational schedules remain constraints: a fleet still has to leave with enough charge for its transport work.
What is V2X?
Vehicle-to-everything is the general category for energy exported from a vehicle. Besides V2G, V2H and V2B, it can include vehicle-to-load (V2L) for appliances and vehicle-to-vehicle (V2V) for another EV. These uses do not all require the same hardware, connection or permission.
Bidirectional EV charging explained
What does every bidirectional system require?
- an EV that permits energy to leave its battery;
- two-way power conversion in the charger or vehicle, depending on the AC or DC design;
- compatible communication between the EV and charger;
- a CPMS, energy-management system or aggregator able to control the intended use; and
- appropriate metering, protection, connection approval and commercial arrangements.
ISO 15118-20 defines communication messages and sequences for bidirectional power transfer between the EV and EVSE. It does not provide the inverter, operate the energy market or grant permission to export. OCPP 2.1 can carry related functions between the charger and management system.
Which option fits which use case?
- Choose V2H as the use-case description when the goal is household self-consumption, tariff optimisation or supported backup power.
- Choose V2B when vehicle energy serves a commercial or shared site under local energy control.
- Choose V2G when energy or flexibility is exported to the public grid through an authorised service.
- Use V2X when discussing the whole category or several export destinations.
The same installation may support more than one mode, but one label does not prove the others. Ask which destination, charging mode, vehicles, firmware and operating rules have actually been tested.
How regulation and amina hardware fit
AFIR does not require every charging point to provide V2G. From 1 January 2027, its technical specifications introduce EN ISO 15118-20 requirements for relevant newly installed or renovated Mode 3 and Mode 4 charging points, but a live export service still depends on the rest of the system.
amina C2 and amina M2 are AC charging platforms with hardware prepared for ISO 15118-20 and bidirectional charging. M2 also provides MID-certified metering, Ethernet, Modbus RTU and local load balancing. These features support an upgrade path; they do not by themselves provide an active V2H, V2B or V2G service.
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