America’s power grid is heading toward a difficult electricity crunch. Could the answer already be sitting quietly in millions of parking lots?

An electric school bus can spend only a few hours each day doing what it was bought to do. The rest of the time, it sits. That idle period is becoming interesting to power companies. The battery that moves children around town in the morning can also store electricity for later use. In some places, utilities are already testing whether that stored energy can help during periods of high demand.

The idea is called vehicle-to-grid, or V2G. It allows electricity to move in both directions between a vehicle and the power system.

School buses have emerged as an early testing ground because their routines are unusually predictable. They return to the same depots, follow set routes and often remain there for long stretches.

One school district is already treating buses as part of its energy system

At Shawnee Public Schools in Oklahoma, four electric buses have been used in a demand-response program with Oklahoma Gas & Electric.

The buses have 210-kWh batteries. During periods of high electricity demand, the district can send stored electricity back to the grid instead of leaving the buses connected only as electricity consumers.

The arrangement also creates a financial incentive. WRI reported that the district can receive payments for participating in the utility program, turning the buses into a potential source of revenue as well as transportation equipment.

The school district does not need to build a separate battery facility for this particular service. The batteries are already inside vehicles it needs for another reason.

The value of an EV battery may depend on when it is used

A utility can have plenty of generation available at one hour and face a much tighter system several hours later. That difference becomes more important as electricity consumption grows and more variable renewable generation enters the power mix.

EV charging can add to the problem if large numbers of vehicles begin charging at the same time.

Smart charging approaches the problem from the other direction. Instead of charging whenever a vehicle is plugged in, software can shift charging toward periods when electricity is less constrained.

V2G adds another option. A compatible vehicle can potentially return some of its stored electricity when the system needs additional flexibility.

The International Energy Agency says controlled EV charging can help reduce peak demand, while bidirectional charging can provide additional grid services.

Electric fleets could be easier to manage than millions of private cars

The owner may decide to leave for work, take a long trip or suddenly need a fully charged car. A utility cannot assume that every plugged-in vehicle will remain available.

Commercial fleets operate differently. Delivery vans often return to the same depot. School buses follow established schedules. Heavy trucks can spend hours at dedicated charging locations.

That concentration gives utilities and fleet operators a clearer picture of when vehicles are available.

WRI reported that at least 26 utilities across 19 states had committed to electric-school-bus V2G pilots by 2025. By August 2026, it reported 32 utilities across 21 states working with school districts on vehicle-to-everything applications.

Truck charging is creating a different kind of electrical infrastructure

Heavy-duty trucks require much more electricity than ordinary passenger vehicles. Their charging sites can therefore become substantial electrical installations in their own right.

Reuters reported on September 17 that Tesla will operate Megacharging sites at three new Forum Mobility electric-truck depots in California. The sites are expected to add 30 megawatts of charging capacity and will serve heavy-duty electric trucks.

This announcement is about charging, not V2G. Still, the growth of large charging depots is relevant to the broader grid question. Instead of dealing with one vehicle at a time, utilities can eventually work with large groups of vehicles concentrated at specific locations.

UL is trying to solve a problem that drivers rarely see

Getting electricity into an EV is already routine. Sending electricity back toward the grid is more complicated.

Bidirectional equipment has to manage that flow safely. It also has to meet technical requirements before utilities can treat it as part of their electrical infrastructure.

UL Solutions announced a V2G certification program in September designed to address that part of the system. Its program covers bidirectional EV supply equipment and testing under UL 1741 Supplement SC, including requirements related to grid interconnection.

This is not the kind of development most EV owners will notice.

There is no dramatic change to the outside of a vehicle. The important work happens inside the charger, control systems and standards that determine whether electricity can move safely between a vehicle and the grid.

The hardest part may be making the economics work

The technology alone does not decide whether V2G becomes widespread. Someone has to pay for the chargers. Someone has to manage the software. Utilities need rules for buying electricity from vehicles. Fleet operators need assurances that their vehicles will have enough charge when they are needed.

Owners also need a reason to participate.

That is why the early programs are useful. They are testing not just whether electricity can move out of a vehicle, but whether the entire arrangement can work in normal operations.

The IEA identifies vehicle and charger compatibility, communications, regulation and business models among the barriers that still need to be addressed.

Some early school-bus projects have also encountered practical problems, including shortages of trained personnel and resources.