For energy saving and CO(2) reduction during idling stops, this study focused on the exhaust gas and exhaust heat of running refrigeration/freezing vehicles. We proposed a novel system which stores the waste heat by means of a chemical heat pump and recycles it as coldness for air conditioning during an idling stop, and performed fundamental experiments of the system. As it is desirable for the reaction system to store heat at the final exhaust temperature of 423 K after passage over the exhaust gas catalyst, we used the calcium sulphate (CaSO(4)) gas-solid chemical heat pump. In the heat storing step, it was found possible to store exhaust heat in the temperature range around 393 K, and the effects of heat storing temperature on heat storing rates were clarified. In the heat releasing step, it was found that cold-heat of less than 278 K was recovered in an evaporator, while hot-heat was generated in the reactor.