How a 94% Reduction in Car Emissions Is Possible Within 15 Years

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Picture the typical taxi trip. A driver pulls up in a Camry or C-Max and a lone passenger gets in, calling out a destination. There are two to three empty seats in the car, gasoline burning, and a driver with a debatable degree of skill behind the wheel — three different types of waste, by any estimation.

According to a study by Berkeley Lab researchers published in Nature Climate Change, you could eliminate all three of the wasteful elements and, along with improvements in traffic patterns, create an autonomous taxi fleet that would cut auto emissions by 87% to 94% by 2030.

The process begins with a concept called “right-sizing.” According to a Berkeley Lab release, scientists Jeffery Greenblatt and Samveg Saxena found that by matching the number of passengers to the vehicle traveling, emissions from transportation would immediately cut in half. Imagine those two or three empty taxi seats out of the equation since only one person hired the ride. Furthermore, imagine the car is self-driving and purely electric, operated by a computer that maximizes energy through driving patterns that may include traveling in packs to cut down on wind drag.

Of course, these autonomous EVs of the near future would be operating on a power grid that is substantially cleaner than the one in place in U.S. cities today. Greenblatt and Saxena concluded these taxis could emit 82% less greenhouse gases than the average hybrid in operation today. Compared to a gasoline vehicle, the self-driving taxi could cut 94% emissions out of the equation. (Without the need for motor oil, the improvement on that front would be a full 100% over today’s gas cars.)

It would take several developments in autonomous car technology and battery efficiencies to make this improvement a reality, but the researchers actually punched in the cost of a self-driving taxi now (estimated at $180,000) to see how it would stack up against your typical New York cab.


Today’s taxis have multiple disadvantages compared to an autonomous cab, and the researchers concluded the self-driving model would return more value than a standard cab, even with a premium of $150,000 added. You would not have to pay a driver, and no human would operate the vehicle. The EVs on auto-pilot would run constantly, pausing only to charge the vehicle’s batteries, making them a cash cow for the operator.

Compared to the average of 12,000 miles driven by a private car, taxis travel somewhere between 40,000 and 70,000 miles. This scale gives them a better chance to make expensive technology pay for itself. As the costs of both autonomous cars and electric vehicle batteries fall due to larger scales, these numbers will only look better for firms running robo-taxis and the people breathing the air of congested cities. Of course, travel is much faster with so many four-seat cars off the road.

Now to the drawbacks. Do you interact with your taxi driver much? Are you ever frustrated by the route he or she takes? Does a lead foot on the gas and brakes rattle you on the way to work when you hoped to check a few emails in peace? These robo-taxis smoothly cruising to your destination seem to be a much better solution, which is a side of autonomous driving that does not get the same press.

As Ford Futurist Sheryl Connelly noted in an interview, autonomous driving is not meant to replace the feeling you get tearing down the road with the top down in your new Mustang. Rather, it can do you a favor on your way to work by picking the best route and giving you a smooth, safe drive while you prep for a busy work day. Commute driving is never fun, and most people would happily give that away in exchange for a robo-chauffeur. (On the way home, feel free to take the back roads and unwind while hugging the curves.)

Meanwhile, a city where 94% of auto emissions disappeared sounds like a nice place to live. All things considered, there are worse things that can happen to the world than autonomous driving — like keeping the current system in place.

Source: Lawrence Berkeley National Laboratory

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