It’s a concept that’s been slowly building momentum for about 20 years: not only can electrified vehicles draw power from the grid, but they can also be used to supply power in return.

Vehicle to grid technology (V2G), as it’s known, is based on the premise that any vehicle with an electrified powertrain – including battery electric, plug-in hybrid and fuel cell vehicle – has the ability to generate power internally. By connecting to the grid via a plug, these vehicles can send the self-generated power back to the utility company.

electrified vehicles

With vehicle to grid integration, different types of electrified vehicles can generate power and send it back to the grid. Image source: University of Delaware.

“It opens up that in the future the utility could dispatch these connected vehicles as a distributed energy source,” said Michael Liu, North America regional manager for energy storage with energy manufacturer BYD America Corp.

Recently, the Los Angeles Air Force Base (LA AFB) put V2G to the test with its 42-vehicle fleet of plug-in electrified vehicles (PEVs).

“When plugged in,” wrote Scientific American, “the electric vehicles at LA AFB produce more than 700 kilowatts of electricity, or enough to power about 140 American households during a hot summer day. At this scale, the LA AFB pilot is the largest demonstration of V2G in the world.”

And potential V2G sources are being added all the time. By the end of the year, approximately 400,000 PEVs will be on U.S. roads. Carbon emission restrictions and purchase incentives for zero emission vehicles (ZEVs) and PEVs continue to be developed, which will drive the count upwards.

nissan-leaf-chargingIn an executive order signed earlier this year, President Barack Obama mandated that 20 percent of the federal government’s fleet must be made up of ZEVs and PHEVs by the end of the decade. Before 2025, this must increase to 50 percent. Similarly, California Governor Jerry Brown set a goal of 1.5 million ZEVs for the state by 2025.

As PEVS become more commonplace, and opportunities for vehicles to supply grid power grow, Navigant estimates that V2G technologies will become part of a $20.7 million industry built around vehicle charging management.

In a recent report, the research firm calculated that – with the proper setups in place – PEVs could supply about 4.2 gigawatts of power worldwide to the grid. Not only is that almost four times the power Doc Brown needed for his time-traveling DeLorean in “Back to the Future,” but it’s enough energy to power 385 homes for a year (based on the U.S. Energy Information Administration‘s average of 10,908 kilowatt-hours per U.S. home each year).

BYD America’s Liu estimates an even higher potential. According to his calculations, when the U.S. reaches 1 million PEVs, they have the potential to supply 10 GW of power.

SEE ALSO: Report: Vehicle-Grid Integration Industry Will Reach $21 Million By 2024

“Some utilities see this is unpredictable power to the grid, I see this is a resource,” said Liu. “At the most, we have a couple of years to recognize this distributed resource.”

Several obstacles will still need to be traversed before V2G becomes a reality in the U.S. For consumers, measures to educate the public on how and when to connect to the grid will be essential. Utility companies will also need to figure out how to manage and use the energy of up to 1 million PEVs.

The University of Delaware has created a dedicated Grid-Integrated Vehicle group to study and understand many of these issues. The pilot project, headed by Professor Willett Kempton, currently brings in about $110 each month per PEV. Separate teams within the group are developing legislative policy, building and testing V2G equipment and analyzing the industry’s market potential.

“There is momentum behind this idea,” said Kempton. “These batteries are a huge resource, and we are going to need them.”