Will autonomous cars make traffic worse?

According to the World Economic Forum and the Boston Consulting Group, autonomous cars have a bumpy road ahead.
2 July 2018

Autonomous cars might not help you breeze through traffic says new report. Source: Shutterstock

When we think of driverless, autonomous cars, we think we’ll breeze through traffic and get to our destination quickly, effectively, and safely.

Each of those three metrics plays an important role in the attractiveness of the overall solution and technology.

However, according to a new report by the World Economic Forum and the Boston Consulting Group, the debut of autonomous cars of the streets will not automatically lead to reduced traffic.

The study ran for roughly three years starting January 2015 and was conducted in the city of Boston. Among other things, it extensively studied the impact of autonomous vehicles on traffic.

Here is a summary of relevant findings:

Shared autonomous vehicles will reduce the number of vehicles on the streets and reduce overall travel times across the city.

According to projections, the number of vehicles on the road will decrease by 15 percent while the total number of miles traveled will increase by 16 percent.

However, travel time will improve by just 4 percent on average – not as dramatic as other studies have forecast, but still an improvement.

Introducing shared autonomous vehicles will worsen congestion in the downtown area, mostly because these vehicles will be chosen as substitutes for short public transportation trips.

Surprisingly, the report’s findings claimed that travel time will increase by 5.5 percent in downtown Boston.

In Allston, a neighborhood outside the city’s core, mobility-on-demand will mainly replace the use of personal cars rather than mass transit, and travel time will decrease by 12.1 percent.

With the new modal mix, Boston will require roughly half as many parking spots, including those on streets and in parking structures.

According to the analysts, local governments hold the key to influencing the impact autonomous vehicles make since they have the power to implement the right policies and incentives.

The report suggested that the greatest effects are likely to come from occupancy-based pricing schemes, in which financial incentives discourage single-occupancy rides. This measure could improve citywide travel time by 15 percent.

“Autonomous vehicles will present an opportunity to rethink the overall design of the city’s streets,” concluded the report’s traffic section.