Power of 42

This article discusses that higher automotive voltages may one day empower a car full of drive-by-wire applications and amenities. This move could save gas, too. For starters—literally-42 volts supply sufficient oomph to turn over a stopped engine at a traffic light with a touch of the gas pedal (or a release of the brake), and so move a driver briskly away from a standstill. Such stop-start, or idle-stop, systems deliver gas mileage improvements and emissions reduction, especially in city traffic. Toyota has already introduced the first production version of these so-called mild hybrids. Besides improving efficiency and decreasing emissions, 42-volt systems make implementing electromechanical valve trains easier. For vehicle control, 42-volts might speed the adoption of brake- and steer-by-wire systems. Toyota’s mild hybrid system uses a belt-operated motor generator to restart a stopped engine, move the vehicle while starting, operate auxiliary equipment when the engine is stopped, generate power while motoring, and recapture energy from braking.