BMW AG may join the group of automakers creating sounds for electric vehicles to make them safer for pedestrians.
Spokesman Tobias Hahn said the BMW and Mini prototype electric cars are not equipped with systems that create noise at low speeds, but added:
"We have been looking into possible technical solutions for a while, and we would be able to add such a feature to our vehicles should this turn out to be a real problem."
Audi and Mercedes-Benz say they have started developing brand-specific sounds, and Nissan and Infiniti have announced the steps they're taking to make EVs audible at low speeds.
BMW's Mini E EV prototype is undergoing trials in Europe, China and the United States. It will begin trials of its ActiveE EV prototype, based on its 1 series, this year. BMW plans to sell its first EV in 2013.
Mercedes wants components in its EVs tuned to deliver a sound that warns pedestrians but does not mimic the noise created by a gasoline engine. Audi is working to create a futuristic engine note for its EV.
Nissan's Leaf EV emits a noise that's a cross between a tiny jet plane and a monorail. The sound was developed with input from the U.S.-based National Federation for the Blind and the Detroit Institute of Ophthalmology.
The M35h gasoline-electric hybrid from Nissan's Infiniti brand has a system that links an in-car sound synthesizer with a speaker built into the front bumper. The system works from start-up to about 19 mph by emitting a range of high and low sounds.