The feasibility of a proposed system that combines a magnesium oxide/water chemical heat pump and a diesel engine as a cogeneration system is discussed based on experimental results. The combined system is intended to utilize the waste heat discharge from the engine by means of the chemical heat pump and to level the heat supply load of the engine, allowing enhanced energy utilization. The thermal performance of the chemical heat pump in the cogeneration system is estimated:based on the results of a packed-bed experiment. The estimation indicates that by storing the waste heat from the engine during low demand periods, the cogeneration system can produce more than several times the standard thermal output of the diesel engine during peak demand periods. Copyright (C) 2001 John Wiley & Sons, Ltd.