The conditioning system of a vehicle is a source of polluting emissions due to the consumption induced by use of this and possible leakage of the refrigerant currently used, characterised by a high potential greenhouse effect. According to new European regulations on the reduction of CO2 emissions, facilities are envisaged for vehicles equipped with Energy Saving systems not detectable in the homologation cycle, such as for example the air conditioner. Furthermore, the EU has banned use of the current  R134a refrigerant  from 2011, decreeing that this must be replaced by fluids with a lower greenhouse effect. As part of the TOPMACS European Project, CRF has developed an air conditioning system that operates with heat recovered from engine cooling based on the technology of the adsorption of liquids on solid matrix. Therefore, functioning of the system has no impact on vehicle consumption. Also, water, by definition environment-friendly non toxic and available in nature, is used as refrigerant. Lastly, integration with a solar panel or boiler of the type currently used on certain vehicles as additional heater permits conditioning with the engine off, making it possible to pre-condition the cockpit and in the case of heavy vehicles, to condition the cab during night-time stop-overs. Adsorption technology is the state of the art in certain stationary conditioning and cooling applications but, due to the space required and weight, has never been applied so far in the automotive field. Within the framework of the TOPMACS project, research into advanced materials, the introduction of certain specific technological innovations and optimised design for application on the vehicle, have made it possible to develop adsorption systems with a high cooling power density of up to 45kW/m3 compared with the 5kW/m3 of the systems available on the market and with an energy efficiency (COP) of 0.5, the highest ever obtained for adsorption systems. These important results, with a major reduction in space occupied, now permit use of these system for vehicle conditioning. The prototype applied on a Fiat Grande Punto can be considered one of the few cars in the world with a conditioning system powered by heat recovered from engine cooling. A similar conditioning system has also been installed in an IVECO Stralis cab.