With electric vehicles poised to dominate roadways in a few years, industry players are preparing to harness their batteries as a massive, distributed clean power plant to meet grid shortfalls during peak times and outages.

The United States Department of Energy (DOE) has launched a collaboration with automakers, charging companies, regulators, and utilities to test the large-scale viability of “vehicle-to-everything” (V2X) bidirectional charging that could make an EV-owner’s car their home’s source of backup power while adding resiliency benefits to the grid, Canary Media reports.

Vehicle charging is already designed to limit peak demand and maximize use of less expensive off-peak power, known as “smart charging”. What’s new, at least beyond numerous pilot projects, is two-way charging technologies and associated financial incentives and other arrangements, known as V2G, that will connect this valuable resource to the grid.

V2G is expected to be a green alternative to load-following peak generation, which in Ontario, for example, is provided by carbon emitting fossil gas plants. Since peak generation is the most expensive power in the system, V2G will also save money.

To secure participation by individual vehicle owners, these savings will be shared. A 2021 study found that V2G revenue could rise as high as US$2,850 per vehicle a year, significantly offsetting the up-front purchase price of EVs, and promoting uptake. In comparison, one-way smart charging only saves owners about US$87 per vehicle per year.

One of the barriers to V2G gaining prominence in the electricity mix is on track to be overcome, Canary Media writes. Limitations in the number of battery-powered vehicles will disappear shortly with government mandates, incentives, and new offerings from the automotive industry. In California, EVs are expected to account for up to 16% of the state’s current electricity demand by 2030, according to the state energy commission.

Other obstacles include a shortage of bidirectional chargers, including software, and the regulatory and incentive framework needed to get vehicle owners to participate. The DOE collaboration and other industry initiatives are under way to address those issues.

For EV owners who may be concerned about reduced battery life due to frequent charging and discharging, software has been developed to prevent damaging discharge cycles.

Utilities worry that power supply from private EVs is beyond their control and unpredictable, as individual owners can decide when and where to make their power available to the grid. Presumably, real world experience at scale, using effective price signals, will determine whether this concern can be overcome. 

Meanwhile, some utilities are focusing on stationary batteries, from building-scale to utility-scale, as a more reliable power supply. However, this option requires an incremental investment in batteries, rather than harnessing the batteries already available in every vehicle. 

Another option is to enter into agreements with the owner-operators of vehicle fleets. School buses are an attractive option, because they can be charged and discharged on a predictable schedule, subject to agreement, and are generally not used during summer peak demand.