Driverless cars won’t be good for the environment if they lead to more auto use

By Giovanni Circella, Director, 3 Revolutions Future Mobility Program, University of California, Davis, Scott Hardman, Professional Researcher, Plug-in Hybrid & Electric Vehicle Research Center, University of California, Davis | The Conversation

For years, self-driving car technology has remained tantalizingly just beyond the horizon. Bold predictions notwithstanding, fully automated vehicles still haven’t appeared in showrooms. But the technology appears poised for a leap forward in 2022.

Companies including Mercedes-Benz, BMW and Honda are bringing so-called Level 3 AVs to market that will let drivers take their hands off the wheel under specific conditions, and virtually every major auto manufacturer is testing self-driving systems.

Automated vehicles hold tremendous promise. Cars that handle most or all of the driving tasks could be safer than human drivers, operate more efficiently and open up new opportunities for seniors, people with disabilities and others who can’t drive themselves. But while attention has understandably focused on safety, the potential environmental impacts of automated vehicles have largely taken a back seat.

We study automated vehicle technologies and how consumers are likely to use them. In two recent studies, our research teams found two creative ways to assess the real-life impacts that automated vehicles could have on the environment.

By analyzing drivers’ use of partially automated vehicles and simulating the expected impact of future driverless vehicles, we found that both automated vehicle types will encourage a lot more driving. This will increase transportation-related pollution and traffic congestion, unless regulators take steps to make car travel less appealing.

More miles, more carbon emissions

Research has previously suggested that automated vehicles could cause people to drive more than they currently do, leading to more congestion, energy consumption and pollution. Riding in a car as a passenger is much less stressful than driving, so people might be willing to sit through longer trips and battle more traffic if they can relax and do other things during the journey. The promise of a relaxed, comfortable commute to work could even make some people move farther away from their workplaces and accelerate suburban sprawl trends.

People would also have the ability to send their cars on “zero-occupancy” trips, or errands without passengers. For example, if you don’t want to pay for parking downtown, at some point you may be able to send your car back home while you’re at work and summon it when you need it. Convenient, but also twice the driving.

This could be a big problem. The transportation sector is already the leading contributor to U.S. greenhouse gas emissions. States like California with aggressive plans to combat climate change have recognized that reducing the number of vehicles miles that people travel is a critical strategy. What if automated vehicle technology makes it harder to achieve these goals?