New cars may eventually use 42V system
By Michael Seaforth
For many people, their cars are almost as important as their homes. They spend an increasing amount of time on the road and expect their vehicles to be equipped with as many gadgets and extra features as space would allow. However, these items can place a severe burden on the electrical system and manufacturers have been forced to explore better ways of meeting a car’s future electrical requirements. Unlike older cars, newer models are often equipped with many items that draw substantial electric current.This has led to proposals for a higher voltage to replace the current 12V system.

The conversion from a 6V to a 12V electrical system took place in 1955. However, the ability of the current 12V system to satisfy consumer demand for more features and to accommodate upcoming advances in technology is in doubt. Systems in use or under consideration such as electric power steering, electric brakes, electronic traction control and active suspensions are all part of the reason for the drive to this new system. In addition the auto air conditioner and engine valves could some day be electrically operated for better flexibility and efficiency.

To accommodate these new loads, a dual voltage, 14V/42V, system has been proposed as the standard for cars in the future. This 14V/42V system is really a 12V/36V system under a different name since a 12V/36V system would typically operate at 14 and 42V respectively. This system is expected to be introduced initially in luxury cars and as prices decrease lower priced cars will also benefit. Smaller loads like lamps and low power electronics would continue to operate at 12V while those demanding more power would utilize the higher voltage. This could mean that some cars may be equipped with two batteries , 12 volt and 24 volt, or that a single battery may be supplied to provide both voltages.

Electrically operated devices can be optimized to suit the load by being operated at exactly the speed needed for maximum efficiency or turned off when not needed. By giving manufacturers the flexibility to replace many belt driven and other inefficient mechanically operated devices with their more efficient electrical counterparts which can be located wherever space is available, better fuel economy and space utilization would be realized.

For more information, visit:
http://auto.mit.edu/consortium

Copyright 1999 - 2001 Innovationhouse.com. All rights reserved.