Vehicle-to-grid charging could prevent three-quarters of electrical transformer overloads by 2050 compared with uncontrolled EV charging, according to a dedicated report on V2G technology published by the International Energy Agency on May 20, 2026. The finding, drawn from a study of San Francisco’s distribution network, underscores how bidirectional charging is shifting from a research concept to a tool utilities will need as EV adoption drives electricity demand higher across every major grid.
The grid-load problem V2G is designed to solve
The rollout of EVs is a major driver of global electricity demand growth, and residential EV charging can draw more power than any other single household load, including heating, cooling, lighting, and appliances.
That concentration of demand at the household level is what makes distribution equipment, particularly neighborhood transformers, vulnerable to overload as EV penetration rises.
A study on the impacts of EV deployment on the distribution network of San Francisco found that V2G charging could avoid three-quarters of transformer overloads by 2050 compared to uncontrolled charging, and half compared to unidirectional smart charging. That comparison matters because unidirectional smart charging, which simply delays when an EV draws power, is already widely promoted as a grid-management tool.
V2G’s additional benefit comes from its ability to push stored energy back into the local distribution network during high-demand periods. Through V2G technologies, EV owners can engage in energy arbitrage, charging the vehicle battery when electricity prices are low and discharging energy back into the grid when prices are high.
Through participation in ancillary services, EV owners are remunerated for flexibly adjusting charging or discharging to assist grid operators in maintaining frequency stability.
Early commercial deployments take shape
Pilots and pre-commercial deployment of V2G are gathering pace across many regions. The first commercial offers for V2G for private EV owners appeared in 2025, although there are few V2G-capable models available, the regulatory landscape for V2G remains fragmented, and standards are not yet clear.
In 2026, the National Electric Energy Agency (ANEEL) in Brazil authorized a V2G pilot project, enabling the use of V2G billing through aggregation with the use of EVs, solar power generation, and energy storage systems. In Korea, Hyundai Motor Group is leading an AC V2G pilot project aligning with a recent grid-code update proposal by the Korean Electric Power Corporation (KEPCO).
One of Australia’s largest utility providers, Origin Energy, is trialing a V2G subscription bundle including a BYD Atto 3, a bidirectional StarCharge V2G Halo charger, and a dedicated energy tariff.
In China, while aggregation and parts of the communication protocols are still under development, the government has set ambitious V2G deployment targets aimed at expanding bidirectional charging facilities in the coming years.
Standards gap slows commercial scale-up
Despite the momentum, inconsistent technical standards remain the central obstacle to widespread V2G deployment. The international communication standard enabling bidirectional power transfer between EVs and chargers with CCS connectors, ISO 15118-20, was published only in 2022, amended in the following years, and has not yet been implemented consistently and universally.
A barrier to full commercialization of V2G in China is that bidirectional charging protocols for the GB/T standard have not yet been fully standardized. Similarly, higher-level communication protocols between the charger, aggregator, and grid are today proprietary or altogether absent.
That fragmentation forces utilities and charge-point operators to build bespoke integrations for each deployment rather than using a common platform, raising costs and slowing rollout.
For US utilities already grappling with the cost of grid upgrades, the V2G trajectory carries direct financial relevance. Load shifting and V2G capabilities provide substantial electricity system benefits, helping reduce peak demand and potentially limiting the need for future grid investment. Utilities that are already planning major distribution spending, as seen in recent rate cases such as a Washington utility’s three-year rate plan carrying more than $529 million in federal tax credits, could find V2G a lever that reduces how much new infrastructure they need to build.
What comes next for US grid planning
Under current policies, full EV deployment would increase total global electricity demand in 2035 by only about 4 percent overall, but the impacts vary sharply by region. Across Europe, EV deployment in road transport increases total electricity demand by more than 10 percent in 2035, compared with an increase of under 6 percent in China.
With the rollout of smart and bidirectional charging, EV owners can reduce charging costs and, in some cases, generate revenue by participating in grid services such as frequency regulation.
The IEA’s V2G technology report arrives as US utilities are already investing heavily in planning tools for the EV charging load wave. A DOE-supported EV load forecasting guide released earlier this year set 20 best practices for utilities undertaking exactly that kind of forward planning. The IEA analysis adds a new dimension: the grid investments those utilities are sizing today could shrink materially if V2G reaches commercial scale before transformer replacement cycles are complete.
