An air-conditioning system and method of climate control for a fuel cell vehicle are provided herein. The system and method include a vacuum enclosure having an adsorber and an evaporator/condenser assembly. A conduit and valve system operates the air-conditioning system in two modes of operation to provide uninterrupted cooling to a passenger cabin, among other things. In one mode of operation, the adsorber is regenerated using waste heat from a fuel cell stack.