Red buses go green

An environmentally friendly fan drive system recently developed by Bosch has already been installed by a number of manufacturers in, amongst other high emission vehicles, buses.

The hydrostatic fan drive, which is compatible with the planned Euro 3 emission levels (due to be introduced in 2005), requires less energy than traditional fans by operating only when required. In the past, fans have usually operated at a speed which reflects that of the engine. In this case the speed of the fan is limited irrespective of the speed of the engine.