42 volt installation

The constantly increasing number of electrical receivers causes, that the demand for electricity in modern cars is constantly growing. More and more electricity is consumed not only by additional equipment, but also modern power units. Direct injection engines require three times as much electrical power as those powered by carburetors.
Today's medium-sized car needs approx. 800 W and a peak power of from 2 do 3 kW. Considering the fact of constant increase in power consumption it is believed, that in the near future the demand for electricity will be approx 4-5 kW and up 14 kW peak power.
To meet this demand, many car companies, m.in. Bosch, Delphi, Siemens, Valeo, Visteon, is developing future-proof electricity supply systems. Together (in this respect, there was a surprising unanimity among competing firms!) established, that the optimal voltage will be in the future 14/42 V, because in the current standard, alternators provide electricity in practice 14 V, a 42 to 14×3, because for safety reasons, a threefold increase in voltage is optimal, which results in a 9-fold decrease in current.
In practice, this means the lowest energy loss, limited load on joints and contacts, possibility of using electric wires with smaller cross-sections, so the benefits themselves!
The 14-volt installation will be used to light the car, radio power supply, sensors and such consumers, which do not tend to peak power consumption. On the other hand, the 42-volt installation will be used to start the engine, fan drive, power steering mechanism, interior and window heating. When timing systems go into production, in which the valves will be controlled by electromagnets, the energy for their launch will be obtained from the 42-volt installation, similar to the start-stop system and the electronically controlled brakes and the steering system.
It is believed, that the 42-volt installation will not become effective from the date jointly agreed by the manufacturers, but it will be established successively, together with equipping the car with modern units and devices. For example. Visteon envisages three phases of its introduction: the first phase is the charging circuit for 4 kW DC converter, second phase – electricity 4+6 kW obtained from a double alternator and third phase – introduction of an integrated starter-alternator system, which will provide peak current from 8 kW upwards.