Ever think of the benefits of EVs? Aside from the more obvious ones associated with not burning quite as much oil, zero tailpipe emissions and ease of driving many will cite the lack of engine noise.  That last point however, may not be such a benefit to all and may even prove dangerous to those with limited or no sight. To address this issue, Nissan plans to program two audible sounds into its 2011 Leaf to make its ultra-quiet EVs less so.

But with blind activists unhappy with the solution Nissan has engineered to alert pedestrians to the Leaf's presence and many EV advocates unhappy with the concept of making a quiet vehicle loud, what really is the best solution?

2011 Nissan LEAF prototype

2011 Nissan LEAF prototype

Nissan have been working for three years to develop an audio system to alert pedestrians that the Leaf is approaching. The work, with the Detroit Institute of Ophthalmology, resulted in two distinct soundtracks being designed for the Leaf. One to announce a low-speed approach of less than 20 mph, and one to be played when the car reverses.

Somewhat reminiscent of an old-school dial-up modem, or discarded sound effects from the 1980s classic Sci-Fi movie Tron, the Leaf's VSP (Vehicle Sound for Pedestrians) alerts are certainly different.

Nissan claims the engineered noises are distinctive enough to alert the listener that a car is approaching, but to be non-intrusive enough to be used in residential areas.

But advocates at the National Federation of the Blind are unhappy with both the reversing noise from the Leaf, an intermittent beep, and the driver enabled nature of the sound system.  Unless law is passed requiring all EVs to make a noise, it is likely a driver operated mute will be present in the initial Leaf models to disengage the system.

The whole issue of audio warnings has caused many hours of conversation among industry professionals, journalists and EV advocates.

In examining the need for sound generators in EVs, many EV advocates cite the naturally occurring noises associated with EVs, such as motor whine at low speed and tire noise at high speed, as being more than enough to alert most pedestrians to the existence of an EV.

Perhaps a good tactic would be to examine areas of the world where EVs are already high in numbers. The streets of London have been full of small low-speed G-Wizzes for many years now and there are no recorded examples of a G-Wiz hitting a pedestrian.

nissan leaf ev 007

nissan leaf ev 007

Similarly, with previous EV generations such as the GM EV1 and Toyota RAV4 EV there appear to be no increased casualty numbers from pedestrians walking in front of an EV.

While it is imperative vulnerable pedestrians and road users are protected from being road casualties of quiet car accidents perhaps car companies should look elsewhere first and be reminded that it is the driver who is responsible for the safety of those around them. In addition, silent vehicles have been on the roads for decades without too many issues; bicycles.

Or Nissan could simply do what GM did with the EV1; use a muted horn for warning pedestrians as and when needed that there is an electric car approaching.

Take a listen to this YouTube VSP video and decide for yourself. We've been told that the actual noise is much quieter than the one in the video.

[download]

[NYtimes]