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Self-driving Cars: Saving Lives AND Energy

Robocars driving together in platoons will use half the fuel that today’s vehicles do

2 min read
Self-driving Cars: Saving Lives AND Energy
Photo: Getty Images

If you follow this blog, you’re definitely aware that the main benefit of self-driving cars is their unwavering vigilance. Someday soon, autonomous vehicle developers hope, you’ll be able to hop in your car, tell it where to go, and turn your attention elsewhere. So will end the tens of thousands of avoidable deaths that occur each year because humans get behind the wheel when they’re drunk or sleepy, decide to text and drive, or otherwise lose focus.

But a Rocky Mountain Institute (RMI) article highlights another important way that robocars will benefit us that we’ve previously mentioned. The environmental impact of driving, says RMI, will be radically altered. Once we reach a critical mass of self-driving cars on the world’s roads, these vehicles will be able to move through highway networks like schools of fish, communicating with each other so they can travel together at close distances without concern for collisions or even traffic jams.

But that’s just the start, says RMI. Make those cars lightweight (because they no longer have to be armored with structural elements meant to protect occupants in the event of a collision) and outfit them with electric powertrains, and you can “reduce vehicle CO2 emissions by up to 95 percent, even when considering the CO2 emitted from the electricity generation,”RMI predicts.

According to the article’s vision of the future, “The city looks and feels different than it used to. Many parking lots and parking spaces are gone, replaced by parks, small businesses, and additional housing…Your car drops you off at work and then engages with the electrical grid to charge and offer services like load balancing, frequency regulation, and energy storage.”

These things, taken together, will change how our driving habits affect our overall energy usage. The Rocky Mountain Institute says its studies indicate that today’s gasoline-fueled vehicles could more than double their fuel economy if they operated within autonomous-vehicle-only zones, because starting, stopping, and idling would be minimized, and gone would be the days of cruising around to find a parking space. And at highway speeds, where most of the energy in fuel is used to overcome drag, platoons of cars spaced closely together would dramatically reduce drag.

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We Need More Than Just Electric Vehicles

To decarbonize road transport we need to complement EVs with bikes, rail, city planning, and alternative energy

11 min read
A worker works on the frame of a car on an assembly line.

China has more EVs than any other country—but it also gets most of its electricity from coal.

VCG/Getty Images

EVs have finally come of age. The total cost of purchasing and driving one—the cost of ownership—has fallen nearly to parity with a typical gasoline-fueled car. Scientists and engineers have extended the range of EVs by cramming ever more energy into their batteries, and vehicle-charging networks have expanded in many countries. In the United States, for example, there are more than 49,000 public charging stations, and it is now possible to drive an EV from New York to California using public charging networks.

With all this, consumers and policymakers alike are hopeful that society will soon greatly reduce its carbon emissions by replacing today’s cars with electric vehicles. Indeed, adopting electric vehicles will go a long way in helping to improve environmental outcomes. But EVs come with important weaknesses, and so people shouldn’t count on them alone to do the job, even for the transportation sector.

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