Legislation Should Consider the Environmental Impacts of Self-Driving Cars

Google's self-driving cars line up outside the Computer History Museum in Mountain View, California.

Many stakeholders believe that autonomous vehicles (AVs) are the future of personal transportation. AVs are cars that lie somewhere on a spectrum of having self-driving capabilities, from cars with intelligent assists, such as automatic braking, to fully autonomous vehicles. Cars that are fully autonomous can function completely without a driver, while those on the lower end of the spectrum offer technological assistance for drivers.

In recent years, automakers have invested heavily in AVs, and as a result, this technology is quickly evolving. Most automakers have integrated automated features, such as parking assist, into their fleets, and some have committed to making fully autonomous cars available for commercial sale within the next decade. Some ride-sharing companies are already incorporating AVs into their service model.

On the regulatory side, Congress and the previous and current administrations have been working to catch up with this quickly developing technology. Congress, for example, has drafted legislation related to safety, cybersecurity, and oversight of AV deployment. Yet while the government is right to focus on vehicle safety and cybersecurity, an important topic is missing from the discussion about AVs, that is, how their deployment will affect carbon emissions from vehicle tailpipes.

AVs and transportation sector emissions

Reducing carbon emissions from the transportation sector is an important part of fighting climate change. Transportation carbon emissions now account for more than one-quarter of all greenhouse gas emissions in the United States—primarily from burning fossil fuels as gasoline and diesel. In 2016, carbon emissions from transportation exceeded those from the power sector. This trend has remained consistent since last year for the first time since the 1970s. Of these transportation emissions, more than half come from light-duty trucks and passenger vehicles.

Some experts suggest that AVs will make driving less environmentally harmful by decreasing congestion and increasing fuel efficiency—decreasing emissions in the process. However, existing research does not draw clear conclusions about the impact that these vehicles will have on the environment. In particular, the research shows that three main factors will determine how AVs affect emissions: their effect on the total vehicle miles traveled (VMT) in the United States, their impact on roadway congestion, and their fuel efficiency.

These three factors are still uncertain. Research suggests that VMT could increase as automation lowers the opportunity cost of drivers, allowing them to do other things while traveling. Alternatively, VMT could decrease if AV technology is used mainly by ride-sharing services that encourage carpooling and efficient driving routes.

While widespread in cars, AV technology is evolving rapidly, and AV emissions are and will continue to be a very real environmental concern for the foreseeable future. If electric technology were to be implemented in AVs, however, automakers could ultimately offer AVs that produced zero emissions, regardless of how many miles are driven. As the electric grid shifts toward cleaner renewable energy, electric vehicles (EVs) are becoming one of the least carbon-intensive transportation options. Electric buses and other electric forms of public transportation are on the rise, exemplifying EVs’ potential to meet most people’s personal travel needs. There has also been significant progress in EV technology as batteries have become cheaper and last longer, and major automakers have touted their shift toward electric fleets in the coming decades.

State-level and congressional action on AVs

Most states are currently considering AV legislation. In 2011, Nevada became the first state to authorize AVs. Since then, 17 states as well as the District of Columbia have passed legislation pertaining to AVs, and governors from four other states have issued related executive orders. In 2017, 33 states introduced AV-related legislation.

This state-level progress has prompted Congress to act. The U.S. House of Representatives is currently debating a bill on AVs. The text of the bill addresses vehicle safety standards as well as cybersecurity and regulatory consistency concerns surrounding AV technology. The bill also establishes an advisory council to make recommendations on a series of topics, including “the impact of the development and deployment of highly automated vehicles on the environment.”

While including environmental concerns in the role of an advisory committee is a good first step, states and the federal government are focused primarily on safety and cybersecurity when it comes to crafting AV regulations. This makes sense, as both are significant concerns that companies should address as they test AV technology on public roads and eventually with human passengers. However, emissions have largely been left out of the conversation. Hearings that led to the legislation moving through the House in June and July 2017 addressed concerns from policymakers, the auto industry, and consumer safety advocates about cybersecurity and safety and congruency across the nation. As Congress moves forward with comprehensive AV legislation, it should use such hearings to dig into the impacts that AVs will have on emissions and the environment. It should then examine how to deploy AVs in the most environmentally and climate-friendly way possible.

A call to action

The current legislation being debated in the House is one step that lawmakers have taken to address important issues surrounding AV technology. Moving forward, Congress has the opportunity to use future legislation to address environmental concerns. Doing so in the beginning of rule-making, as Congress crafts the laws that will govern the future of self-driving cars, is crucial.

Congress should hold hearings and examine key questions about AVs and emissions, including how AV deployment will affect overall travel patterns and the number of miles driven by cars, as well as how fuel efficient new AVs will be. After considering these questions, Congress should develop legislation that ensures that the deployment of AVs is part of the solution to transportation emissions, not a contributor to climate change. To further mitigate AVs’ impact on the environment, Congress should also promote the use of EV technology in AVs, which would make the technology both environment and consumer friendly.

This is not to say that Congress needs to act alone to bring emissions to the forefront of the discussion. Nonprofit organizations, automakers, safety experts, and government leaders at the state and local levels also have a role to play in considering the impact of AVs in every sphere, including the environment. Even in the early stages of AV regulatory policymaking, vehicle emissions should not be ignored or treated as an afterthought.

Myriam Alexander-Kearns is a policy analyst for Energy and Environment Policy at the Center for American Progress.