Abstract
The need to integrate the air conditioning system of industrial vehicles with an Auxiliary Power
Unit (APU) is becoming more and more important to assure comfort conditions to drivers when the
vehicle doesn´t travel, both due to energy saving and pollutions reduction, and security of the on-road
behaviour of drivers after rest periods.
Presently, on the market, systems are available that rarely meet the requirement of long distance
drivers, particularly during the day stay in hot country climate.
Main problems are: size of devices, weight, cost, produced noise and pollution. Besides, such
devices are often a duplicate of the on board air conditioning system and work only with the engine
switched on. But, due to the reduced available space, and other limits, the performances are far from
being satisfactory. Furthermore these devices can be used only for a limited length of time,
maximum a few hours. On the contrary a long term use (many hours) is strongly required by the
drivers, and this request forces the producers to develop a specific APU for this purpose.
The present paper shows the activity of IVECO, supported by University of Rome Tor Vergata, Fiat
Research Centre (C.R.F.) and WEBASTO, in developing a new system able to meet the driver´s
requirements in the most extreme ambient conditions existing in Europe, and to guarantee comfort
conditions for at least 8 hours.
The use of fuel cells is foreseen to supply power to an electric engine that moves the compressor of
the on board air conditioning system when the engine is switched off. Characteristics and
performances of the new designed system are compared with a traditional APU using a thermal
engine.
On board space required by the new system may be much lower, due to the strong integration with
the existing air conditioning system. The best temperature distribution in the cab can also be
assured. Last but not least, the working time of both APU (fuel cells or thermal engine) is limited
only by the on board fuel storage.
Keywords - Fuel-cells, Auxiliary-Power-Unit, Air-Conditioning, Industrial-Vehicles, Pollution-reduction