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U.S. Says EVs Must Make Noise to Warn Pedestrians

And Tesla wants to use robocar smarts to transmit the noise selectively

1 min read
A Tesla car with blank speech bubbles around it
Photo: Tesla; Icons: iStockphoto

Electric vehicles must make noise to warn pedestrians of their coming by 2019, U.S. road safety regulators said this week. And the measure is grist for our mill here at “Cars That Think” because Tesla Motors appears to be developing a robotic solution to the problem.

The National Highway Transportation Safety Administration announced on Monday that noisemakers would be needed in pure electric and hybrid vehicles operating at speeds under 30 kilometers per hour (19 mph). At higher speeds they evidently make their own noise, thanks to resistance from wind and road.

The first clue to Tesla’s plans, Electrotek reports, is the statement Tesla’s Elon Musk made at a press conference back in 2013. “I think the sensible and ideal thing long-term is to have proximity sensors that direct a pleasant sound in the direction of where somebody is walking,” Musk said. The second clue came earlier this year in the form of blueprints apparently leaked from Tesla. Clearly visible are structures labeled “pedestrian speakers.”

It’s unclear whether regulators will accept Musk’s proposal to beam noise with laser-like focus to spare the ears of the unthreatened. On the other hand, just broadcasting the noise takes away a key EV marketing advantage: silence. (Except for the motorcycle market. Some fans of Harley Davidson’s iconic bikes have disparaged that company’s planned electric version for its un-Harley-like purr.)

Many EV motorsports events already require the noisemakers to protect onlookers, photographers and pit crew. At this summer’s motor race at Pikes Peak, Colo., local stores sold modified car alarms to racing teams for just this purpose. The price: $8.

Toyota, which inaugurated modern EV technology with its Prius hybrid, has supplied optional noisemakers for years. So has Nissan, whose Leaf was the first mass-market all-electric car. 

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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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