If energy and transportation planners stop seeing their sectors as separate markets for batteries—a World Resources Institute researcher argued last week—there will be more than enough energy storage to go around.

“An electric vehicle, because of the battery, is really both a mobility asset and an energy asset,” said Camron Gorguinpour, WRI’s global senior manager for electric vehicles, “and so we really want to start looking at the duality of electric vehicles rather than really just trying to focus on one thing.”

Vehicle-to-grid technology is not a new idea—China jumped on it early—but it looks like an increasingly promising idea as electric-vehicle adoption takes off.

The International Energy Agency’s most conservative estimate puts 130 million electric vehicles on the road by 2030, and Gorguinpour said those vehicles will contain almost ten times the amount of energy storage needed by the grid.

The IEA’s most aggressive estimate, 250 million EVs, would mean 6 percent of the batteries in the automotive fleet could meet all of the grid’s energy-storage needs.

“When we talk about the dual nature of electric vehicles as energy and mobility assets this is really what we're talking about,” he said.