Self-driving cars or the autonomous vehicles have created a great deal of hype. With transportation giants such as Tesla, Ford, and Google backing up the technology and using it to manufacture driverless cars, the future looks very promising. In fact, self-driving vehicles have piqued the interest of people all around the world, and according to an ARM survey conducted with 4,000 consumers worldwide, 5fo5% people said that they would trust an autonomous car if its safety record were proven to be better as compared to a human-driven car.

A survey conducted by Roads and Transport Authority (RTA), Dubai over the course of two months, revealed that 91% of users were satisfied with their driverless transport and 80% believed that these cars could decrease congestion. The survey was based on a strategy that is set to transform 25% of all trips in Dubai to self-driving journeys by 2030.

Even though the primary concern of those working with self-driving cars has always been safety and fewer road accidents, experts are now looking into other factors that affect whether or not these cars will be efficient.

Traffic congestion due to driverless vehicles is one of the elements under close observation. Though this debate has been going on for quite some time now, there are two very conflicting views on the subject.

We’ll look into both these arguments so you can understand the situation a little better. But first, let’s recognize the science behind traffic jams.

What is a Phantom Jam?

We’ve all been in a situation where we had to wait for hours on the highway just to make it in time for the office meetings. Traffic jams are a phenomenon that has existed since the number of cars increased. In layman terms, a traffic jam happens when there are a lot of cars and not enough road to accommodate them all.

Traffic jams not only are annoying for the public, but they have disastrous consequences for businesses, especially trucking firms. Surprisingly trucking firms had to spend an additional $63.4 billion in 2015 as operational costs due to traffic congestion.

Contrary to common belief, these congestions don’t always happen because of an accident, vehicle breakdown, or road maintenance. In fact, most times, this blockage cannot be blamed on anything. Phantom jams are traffic congestions that have no reason behind them. In this type of gridlock, the traffic builds up and then eases on its own within minutes or several hours. Though you may think that there’s not a lot of management involved, the truth is that there is a lot of mathematics behind it.

So, now that you know what phantom jams are let’s dive right into whether or not driverless cars can get rid of these issues.

Evidence That Suggests Self-Driving Cars Will Cut Traffic

In 2008, a group of Japanese researchers conducted a survey that explains why we are often stuck in stop-and-go traffic jams. According to this experiment, the main reason behind the congestion was very simple – inconsistent driving speeds.

When one driver is driving too fast, he has to put his foot down on the brake to avoid hitting the vehicle in front. As a result, the car following this speeding car over-compensates for the sudden braking and the cycle continues. This ripple effect is carried down to other vehicles, and this ultimately results in traffic congestion or a complete stop. This study was particularly helpful in revealing the cause of phantom jams. However, it couldn’t come up with a solution, until now.

Forbes highlighted a new study that suggests that the days of traffic jams may be coming to an end with the advent of self-driving cars. In the survey, 20 cars were put on the track with 20 humans on the driver’s seat. The only instructions that were given to the drivers were to drive as they would in a rush-hour jam, follow the vehicle in front of them without falling behind, don’t hit the car and don’t pass the car ahead. Though they were instructed to catch up if a gap started opening up, they weren’t allowed to tailgate.

You can view the experiment in the following video.

19 of the drivers in the vehicles didn’t know that there was one autonomous car amongst them and that it took control after 126 seconds because a jam had started to unfold at just 79 seconds. The car’s target speed was set to 23.4 km/h in the beginning and was increased gradually to 27 km/h.

The researchers concluded that controlling just one car can improve the congestion situation or even get rid of it entirely – at least in the absence of another blockage. Surprisingly, the research also found that the fuel consumption of the cars was reduced by a whopping 40% just because the speeds of the vehicles were adequately controlled.

On the Flipside

However, not everyone agrees that self-driving cars can improve traffic conditions. In fact, an interesting article on Business Insider interviewed an expert who suggests otherwise. According to this article, Lew Fulton, co-director of the STEPS program at UC Davis Institute of Transportation Studies (ITP) thinks that congestion issues won’t be solved unless a zero-occupancy pricing system is put in place. Fulton said that with driverless cars on the road, owners wouldn’t be bound to run errands on their own and this will result in an influx of traffic.

Other than zero-occupancy, Fulton also predicts that congestion could worsen because when manufacturers such as Lucid Motors explore comfort in self-driving cars, people wouldn’t need to stop and rest on longer commutes because they would be relaxed in the car.

The verdict is still out on whether or not the driverless car can reduce traffic congestion but the good news is that work is being done continually.