Preparing Our Towns & Cities for a Fleet of Self-Driving Vehicles
A substantial shift in transportation options is emerging, with various technologies advancing to market for connected and highly automated vehicles (C/AVs). Our nation’s $1,000 per capita annual crash costs may plummet – as technologists and manufacturers work hard to publicly deliver communicating and self-driving vehicles.
Connected vehicles communicate basic safety information – including their position, speed, and direction, in order to avoid crashes, improve traffic signal timing plans, and receive valuable feedback from roadside devices that alert vehicles or their drivers to downstream issues (like tight, icy bends in the road).
These dedicated short-range communications (DSRC), which cost less than $100 per vehicle, will probably be required on new passenger vehicles by 2020. Although adding such radio-signal technology to existing vehicles will be rather easy, it will require that drivers react to the resulting audible alerts, rather than rely on embedded automated systems that exist on many newer vehicles (like emergency braking and lane-keeping assistance).
Autonomous Vehicles (AVs) will transform personal and freight transport patterns by providing travel alternatives that compete favorably with existing mainstays. While human driving may disappear, our road-use demands, or vehicle-miles traveled (VMT), will rise. As consumers opt to purchase or rent AVs, demand will fall for flights to nearby regions, intra-regional bus use, and inter-regional goods shipments by train.
Our research results suggest that 70 to 87 percent of our light-duty vehicle fleet will be fully self-driving by 2045. However, this is without any proactive policies such as requiring only self-driving mode in a city’s downtown or along certain freeway lanes. Falling technology prices and increases in households’ willingness to pay for such technologies, much like we have seen with smartphones and other devices, should help Americans embrace connected and self-driving vehicles.
In our research to determine the present feasibility of implementing these technologies, we found that Americans would be willing to pay $67 for DSRC connectivity and $5,857 for fully self-driving cars. As expected, readiness to invest in such advances rises as one’s friends and neighbors acquire the technologies. Moreover, almost 60 percent of all individuals indicated wanting to use self-driving features soon, for at least some of their current trips, but affordability and equipment failure are top concerns.
The value of safer journeys, with lower operator burden and possibly avoided parking costs, is substantial. We estimate AVs’ social benefits to be roughly $3,000 per year per vehicle initially, rising to nearly $5,000. Moreover, shared AV fleets suggest an important opportunity to improve fuel economy (thanks to smaller vehicles), reduce emissions (thanks to keeping engines warm and avoiding cold starts), reduce parking needs (as households reduce their own vehicle holdings), lower travel costs (for those who drive their vehicles less than 5,000 miles per year), connect to major existing transit lines (as a first-mile, last-mile service), and improve mobility and access for those without vehicles or unable to drive (including tens of millions of elderly Americans who regularly avoid night-time driving and other endeavors).
All told, AVs may save the United States’ economy roughly $430 billion annually. However, we must plan for the added travel demands and VMT that our networks will be asked to support. Congestion-based tolls and vehicle-type tolls are helpful in managing added demands. Congestion pricing is designed to keep traffic moving, and is especially valuable at regional bottlenecks, like bridges.
Credit-based congestion pricing (CBCP) comes with travel credits or budgets for each traveler, so that everyone in a region owns a share of the network and will pay out of pocket only after exceeding their monthly budget. Our research shows how CBCP policies can improve the welfare of most travelers, while better reflecting the true costs that each of us is imposing on others (those behind us in the traffic stream) when we enter a congested roadway.
Additionally, as we move toward 100 percent C/AV use, traffic signal systems can be replaced by roadside monitors that send instructions to individual vehicles and mini-platoons of vehicles to make maximal use of an intersection. By taking advantage of the information collected, traffic signals can safely offer pedestrian and bicyclist phases – especially as non-motorized travelers add connected technologies to their phones, backpacks and bikes in order to help smart vehicles anticipate their presence. This will lower the thousands of pedestrian and cyclists deaths this country experiences every year.
Our simulations also suggest that every shared AV can replace about 5 to 10 privately held vehicles, which provides many benefits. With a fleet of shared smart vehicles, we can promote dynamic ride-sharing, where neighbors, colleagues, and complete strangers opt to share their vehicles, saving on travel costs, congestion, and emissions. Such systems may be critical in most cities to counteract the added VMT that comes with easier motorized travel.
Together, connected and automated technologies offer tremendous opportunities for improved access, mobility, and safety across the country. But it is important that we promote the most effective features of these new technologies, helping to avoid more serious congestion and ensure more sustainable systems.