Why Self Driving Cars Could Actually Make Traffic Nightmarish: Analysis

The fully autonomous cars that big-name tech companies like Tesla and Waymo are striving to make a reality have been the subject of some pretty bold claims. Even the presence of a few self-driving cars on the road, some have alleged, could drastically reduce the prevalence of traffic jams. But new analysis published Thursday in the journal Transport Policy suggests not only that the traffic jam-alleviating prowess of self-driving cars has been over-sold, the presence of these cars on the road might actually wind up making traffic worse. Like, a lot worse.

The problem? Existing models underestimated the potential for robot-fueled gridlock brought about by all those autonomous vehicles aimlessly cruising through cities to avoid parking fees. Instead of posting up in a parking garage while you’re shopping, AVs will be incentivized to slowly circle around the block to dodge payments. This will result in excruciating road congestion even if only a couple thousand autonomous cars are introduced.

“Parking prices are what get people out of their cars and on to public transit, but autonomous vehicles have no need to park at all. They can get around paying for parking by cruising,” he said in a statement. “They will have every incentive to create havoc.”

Self driving cars could solve a lot of safety issues but it could introduce other annoying ones. 

The paper’s author, Adam Millard-Ball, a professor of environmental and urban studies at the University of California, Santa Cruz, estimates that self-driving cars will become widely available within the next five to 20 years. But in addition to in-car entertainment centers and lounge seating, they’ll also bring with them a hefty dose of road rage.

Millard-Ball isn’t just shooting from the hip here. Using data from downtown San Francisco, he generated a simulation of 2,000 autonomous cars in the sprawling California metropolis and his findings were not reassuring. The AVs slowed down traffic to less than 2 miles per hour, which understandably would bring anyone to the brink of insanity. But this is also thanks to steep parking prices which make cruising around indefinitely too economical.

Parking at San Francisco’s famous Fisherman’s Wharf costs $9 per hour on weekdays. That’s compared to the 50 cents per hour Millard-Ball estimated it could cost all-electric cars to wander around. The savings are less drastic for fossil-fuel burning cars. But there’s a play that the United States could take from Europe and Asia’s playbook to solve this impending issue: congestion pricing.

waymo self driving car
Imagine this van driving at 5 miles per hour in downtown San Francisco.

Drivers in London pay a fee of about $15 to enter the city center and cities like Singapore and Stockholm use similar rules. New York State is also debating implementing them. That might be a tough sell for drivers right now, but Millard-Ball sees it as a way to future-proof roads for the self-driving cars to come.

“The public never wants to pay for something they’ve historically gotten for free,” he said. “But no one owns an autonomous vehicle now, so there’s no constituency organized to oppose charging for the use of public streets. This is the time to establish the principle and use it to avoid the nightmarish scenario of total gridlock.”

In fact, people have been using semi-autonomous car features to already dodge parking tickets. A Tesla owner in Wisconsin used his vehicle’s “Summon” feature to move his car to another parking spot because of the Janeville, Wisconsin’s two-hour parking limit.

Of course, this is no reason to keep self driving cars from being developed. The accidents avoided by taking drunk drivers and texting drivers off the road, alone, will save thousands of lives on their own. But autonomous autos will also have their draw-backs, too. The time to start preparing for them is now.