The balance of power

Intelligent management of electrical loads and innovative power-saving technologies allow current 14-V electrical architectures to accommodate features and capabilities once thought to be exclusive to 42-V architectures.

Costs for the new electronic features that consumers want in their future cars are measured in more than just dollars; watts are also important. The increasing demand for power and the limits of today's 14-V systems have been apparent to vehicle manufacturers for well over a decade. Recent data show an increase of about 150 W occurring each year. With several new electrical loads identified that are in the kilowatt range, the industry has initiated plans for the next vehicle power-supply system. However, the cost of the transition to that 42-V configuration has brought alternatives and is delaying its introduction.

What is occurring now is a case of supply and demand. Suppliers know how to provide higher power with inline or belt-driven 42-V starter/alternators. If automakers need 5 kW (2 kW at idle) of power, they even have choices from various suppliers. These same techniques can be applied to 14-V systems, delaying the need for 42 V on the highest-power-consumption vehicles. These techniques will also prolong the use of 14 V on intermediate vehicles, making the supplier's investment well worthwhile.