Electric vehicle-to-home energy supply could cut EV charging costs by up to 90%

Electric vehicle (EV) batteries could save homeowners thousands of dollars on utility bills while helping cut emissions from the power grid, a new study reveals.

The researchers, from the University of Michigan and Ford Motor Company, tested several scenarios related to vehicle-to-home charging (V2H). They found that V2H could save drivers money, reduce emissions, and encourage people to switch from traditional internal combustion engine vehicles.

Leveraging V2H charging

V2H leverages bidirectional charging to allow drivers to use the power stored in their electric vehicles, similar to a generator—except without burning gasoline. The team emphasized the flexibility V2H allows.

“Putting vehicle batteries between the electricity grid and homes makes it possible for homes to buy electricity for all household uses when it is cheap and clean—for example, in the afternoon, when there is a lot of solar power—and to store it in the car’s battery for later use,” said Parth Vaishnav, an assistant professor in the U-M School for Environment and Sustainability, or SEAS.

“If you’re buying an EV because you want to cut greenhouse gas emissions—or if you’re making an EV because you want to cut greenhouse gas emissions—this tells you that, in addition to reducing greenhouse gas emissions from transport, the EV could also help cut building sector greenhouse gas emissions.”

V2H could also reduce a homeowner’s lifecycle greenhouse gas emissions by 70 to 250 percent, or by 24 to 57 tons of carbon dioxide, on average. According to a press statement, that would be equivalent to 80 to 190 one-way flights between New York and Los Angeles.

A comprehensive outlook on V2H

Though scientists and companies have been touting the potential of bidirectional charging and V2H for a while now, Vaishnav and his team claim they have provided the most comprehensive investigation to date on the benefits for homeowners and the environment.

For their research, the team used a mid-sized SUV and considered a variety of factors that vary by location. These included grid energy costs, emissions, and outdoor temperatures, which affect efficiency.

The team broke the US into 432 regions, defining them based on shared climate and grid conditions. Overall, their study showed that V2H charging offers significant economic benefits that could encourage drivers to adopt it.

“When people think of EV charging, it’s usually thought of as a burden, a cost that is added to your electric bill,” Jiahui Chen, lead author of the study, explained. “But, with this kind of technology integration, we can make charging an asset.”

The scientists also stated that V2H technologies are still in the early stages of development. This means it may take EV owners a while to fully reap the benefits. However, the new study highlights the potential of the technology, providing a stronger incentive for its development.

The findings were published in a new paper in the journal Nature Energy,