Though not the main selling point of electric vehicles, their quiet operation has often been cited as a great side benefit. Legislation that would require electric vehicles to make noise, however, is in the works. The technology is available to make cars noisier, but the government is considering mandating it.
The problem with silent vehicles
At low speeds, many hybrids and electric vehicles make very little noise. At speeds above 20 miles per hour, the air resistance against the vehicle does make some noise, but it is usually not as loud as gasoline-powered engines. While this is great news for noise pollution, it is bad news for many of those who rely on vehicles making noise. Pedestrians, cyclists and sight-impaired individuals often cannot identify which direction a hybrid or electric vehicle is coming from until they are very close. Limited studies have shown that hybrids and electrics are twice as likely to collide with pedestrians at intersections and parking lots, where the vehicles are moving at very low speeds.
Vehicle companies addressing the issue
Some vehicle companies, such as Nissan, are already working to address the issue of vehicle noise. The Nissan Leaf is reportedly going to be making a “futuristic buzzing noise” in later models. Separate companies, such as Lotus Engineering, are developing kits that add realistic engine rumbling to hybrid vehicles. One kit makes a Prius sound like a race car. Kits are also available to create 8- and 12-cylinder vehicle sounds, so technology is already available to add noise to quiet hybrids and electric vehicles.
Trying to create international standards
The National Highway Traffic Safety Administration is considering creating requirements for electric vehicle noise. The European Union is also considering similar regulation. Some vehicle makers have considered sounds based on natural noises, but many sight-impaired advocacy groups argue against this option. The Society of Automotive Engineers is working to create what it hopes will be worldwide standards for electric and hybrid noise to ease the transition and prevent a virtual cacophony of varying electronic noise on highways and freeways.