Vehicle-to-grid (V2G) technology enables bidirectional energy transfer, allowing electric vehicles not only to draw energy from the grid but also to feed it back into it, effectively turning them into mobile batteries. This concept aligns with the broader trend of vehicle-to-everything (V2X) technology, which encompasses various forms of bidirectional energy exchange.
The rise of bidirectional EVs: EVs with V2X capability
A growing number of battery electric vehicles (BEVs) now offer V2X capabilities, including vehicle-to-grid (V2G), vehicle-to-home (V2H), and vehicle-to-charge (V2L) functions, allowing them to discharge energy for various applications. Notable models with V2G capability include the Nissan Leaf, one of the first to adopt CHAdeMO, and newer models equipped with CCS, such as the Volkswagen ID.4, ID.5, and ID.Buzz, as well as the Polestar 3.
Other EVs, such as the Hyundai Ioniq 5 and Kia EV6, only support V2L, allowing users to power small devices or appliances directly from the vehicle. As more automakers adopt V2X technology, vehicles like Ford’s F-150 Lightning and GM’s Silverado are expanding the potential of EVs beyond transportation, improving grid resilience and offering backup power solutions. IDTechEx compares several V2X-capable EVs by capacity, discharge speed, and charging standard in its report, “Electric Vehicle and Fleet Charging Infrastructure 2025–2035: Markets, Technologies, and Forecasts.”.
DC vs. AC V2G Systems: Knowing the Options
There are two main approaches to V2X that differ depending on the inverter's location relative to the vehicle and the charging point. The inverter can be located internally in the EV, so the vehicle discharges alternating current (AC) to the charger. Or it can be external to the vehicle and located inside the charger, so the vehicle discharges direct current (DC).
V2G DC systems currently offer higher discharge speeds, typically ranging from 15 to 100 kW. These systems are primarily implemented using the CHAdeMO protocol and are characterized by lower vehicle power electronics costs. However, they have a drawback: higher infrastructure costs, as they require specialized DC charging equipment.
SWOT analysis of AC vs. DC V2G systems. Source: IDTechEx - "Charging infrastructure for electric vehicles and fleets 2025-2035: Markets, technologies and forecasts"
Looking to the Future: The Future of V2G Technology
As the number of V2G-capable BEVs increases, the potential impact on the grid could be substantial. IDTechEx forecasts that the annual market share of V2X (bidirectional)-capable light electric vehicles will grow from 5% in 2023 to over 20% in 2028 in the United States. By enabling widespread adoption of V2G, EVs can contribute to a more resilient and flexible energy system. This vision, however, depends on collaboration between the automotive and energy sectors. Energy providers will need to develop dynamic pricing models and infrastructure to support the fluctuating energy demands of V2G, while vehicle manufacturers must continue to develop affordable, V2G-compatible vehicles.
Heavy-duty vehicles, such as buses, coaches, freight vehicles, and construction equipment, which have predictable usage patterns and downtime with high-capacity EV batteries, also offer good V2X potential. The North American market is already successfully testing this strategy with public school buses. IDTechEx's report on the charging infrastructure market analyzes several V2X case studies to provide an overview of global projects.
With continued advancements and a commitment to standardization, V2G technology could soon become a widespread feature that would allow electric vehicle owners to actively participate in the energy ecosystem.
Author: Shazan Siddiqi, Senior Technology and Technical Sales Analyst at IDTechEx
