Robot Taxis Could Cut Greenhouse Gas Emissions 82%

Photo: Getty Images

The next time you’re flailing your arm out to a sea of taxi cabs during rush hour, imagine an automated car swinging right up to the curb to pick you up. With Google, Uber, Nissan, and robo-taxi start-up Zoox planning to infiltrate the taxi industry with the self-driving cars, cab driver may become a career of the past. 

In addition to the obvious incentives of automated cars, new data predicts that such a taxi system would put only the most cost-effective vehicles on the road and cut greenhouse gas emissions.

Based off of a forecast of U.S. car emissions and gasoline prices in 2030, sustainable energy researchers at Lawrence Berkeley National Laboratory, in California, found that the emissions of a self-driving taxi would be 63 to 82 percent lower than those of a privately owned hybrid electric car, and 90 percent lower than today’s privately owned gasoline cars.

If just five percent—or 800,000—vehicles in 2030, were converted to robo-taxis, it would save 7 million barrels of oil per year and reduce up to 2.4 million metric tons of CO2 emissions per year.

Automated car systems may cause an increase in the number of vehicles on the road. But, according to the study’s lead scientist, Jeff Greenblatt, the emission cuts are so dramatic that the amount saved would negate impact of those extra cars.

“Electric technology and small vehicle size can make autonomous driving so efficient that we can tolerate increased mobility and still come out way ahead when it comes to efficiency and carbon emissions,” says Greenblatt.

Greenblatt and his team modeled their data on heavily driven taxis that would make dozens of trips per day and churn through batteries fast. Energy savings per trip increased by a factor of two when one- and two-person rides  were handled by a vehicle sized to carry only those passengers.

Today, even partly-automated cars aren’t cheap. But, according to Greenblatt, by 2030 automation technology could add as little as US $1,000 to $1,500. But the researchers used a generous estimated cost of $5,000 in their calculations.

At these costs, things aren’t looking too optimistic for traditional cab drivers who are already getting competition from web-enabled alternate cab services such as Uber and Lyft. However, it is going to take many years for major automated car systems to be rolled out, and there are many challenges that city planners need to consider first.

Greenblatt believes we are going to see an environmental benefit. “Once people start trusting the technology, maybe we can breathe a little easier about using automated vehicles.”

The tonnage of carbon dioxide savings in this post was corrected on 7 July.


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