One of the burning questions facing self-driving carmakers is whether it makes sense to go all-electric. Some companies, like GM-owned Cruise, are all in on battery-electric vehicles, seeing both self-driving and all-electric as the future. Others are keeping one foot in the present, like how Waymo is building a fleet that includes both all-electric Jaguar I-Pace SUVs and gas-burning Chrysler Pacifica minivans.

Argo AI, the Pittsburgh-based self-driving company that’s backed by Ford and Volkswagen, has concerns about an all-electric fleet, especially when it comes to recouping the cost the expensive technology that makes the car autonomous. The company’s CEO, Bryan Salesky, sat down with Verge editor-in-chief Nilay Patel and senior transportation reporter Andrew Hawkins on The Vergecast to explain why.

“The cars need to be on the road earning money,” Salesky said. “The longer it sits at a charger, the more time that goes by that it’s not making money ... And the potential that if you use fast charging, it’s also destroying the battery chemistry, which then has you replacing batteries on a more frequent schedule, which also is not good for the environment.”

Listen here or through a podcast player of your choice to hear the whole discussion.