Air-conditioning system for vehicles with on-board hydrogen

Abstract Electric vehicles with on-board hydrogen store not only the corresponding chemical energy of the H 2 , but also a significant amount of potential energy in the pressurized gas. This energy is provided by a compressor at the fueling station and so far, it is wasted by throttling the H 2 to the fuel cell supply pressure. An “open” metal hydride cooling system can convert part of this potential energy into cooling power. In this publication, results for an experimental lab-scale setup of such a cooling system are presented and discussed in the vehicle context. The lab-scale system consists of two plate heat exchanger based reactors filled with 335 g and 353 g of Hydralloy® C5 hydride material. At 10 °C an average cooling power of −532 W or −586 W could be determined for cycling times of 100 s or 75 s, respectively. Due to the small lab-scale reactors used in this study, this value is reduced to −76 W, when the efficient cooling power between 30 °C and 10 °C is determined. To conclude the results, scale-up effects and the relation of hydrogen flow and cooling power are discussed as well as a possible integration into a vehicle.