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Will We Prove That Autonomous Cars Are Safe Before They Go on Sale?

It will take hundreds of billions of kilometers of testing to confirm the safety of self-driving vehicles, say analysts

2 min read
Will We Prove That Autonomous Cars Are Safe Before They Go on Sale?

It could take hundreds of billions of kilometers of driving before autonomous cars are pronounced safe, according to a new report. Logging that many kilometers, in order to generate a large enough cache of safety data, could take decades. To put those hundreds of billions of kilometers in context, Google’s self-driving cars have driven 2.4 million kilometers since 2009.

Analysts from the nonprofit RAND Corporation in Santa Monica, Calif., who authored the report say that proving self-driving cars to be as safe as human-controlled ones will require robocar developers and testers to employ test methods—virtual testing and simulators, mathematical modeling, and scenario testing among them—that don’t require the rubber to meet the road.

The U.S. National Highway Traffic Safety Administration says that more than 90 percent of car crashes are caused by human errors such as speeding, drunk-driving, distraction, and fatigue. Besides remaining ever alert and being incapable of failing a breathalyzer test, self-driving cars’ ability to communicate with each other and fixed infrastructure like traffic lights could make driving pretty efficient.

But the statistics will never stack up enough for us to be completely certain that accidents won’t happen, the analysts say.

That’s because human error is a critical benchmark with which to compare self-driving cars. And though we tend not to view it that way, the rate of road injuries and deaths because of human error is pretty low compared to the total distance traveled. Americans drive roughly 4.9 trillion kilometers every year, according to the Bureau of Transportation Statistics, and for every 160 million miles driven, there are about 77 injuries and about 1 death. To prove that autonomous cars are safe—that they have similar or lower injury and death rates—they would have to log comparable travel distances, the anslysts contend. And that will be impossible before self-driving cars are sold to the public.

Google seems to be aware of these limitations and the safety concerns related to robotic cars. The company’s Chris Urmson recently outlined plans for an incremental roll-out of the cars, with vehicles meant for sunny weather and wide-open roads coming out before models designed for places where it snows and traffic is regularly snarled.

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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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