The primary objective of this paper is to propose the integration of a hot water cooling system with a desiccant-assisted evaporative cooling system for air conditioning a data center. The feasibility of the integrated system is analyzed by a detailed energy simulation for a model data center by using TRNSYS (transient system simulation) 16 with a commercial equation solver program. The energy saving potential of the proposed system is evaluated by comparing it to a conventional air handling system with an air-side economizer serving the model data center. The results show that the proposed system saves more than 95% of the peak power demand and 84% of annual operating energy consumption with respect to the conventional air conditioning system for the data center. This advantage in energy savings is primarily obtained by the use of water-side free cooling in the hot water cooling system and the evaporative cooling effect enhanced by the liquid desiccant system in the air-side supply. Fan energy savings caused by reduced air flow in the proposed system also contributes to the reduction in operating energy. (C) 2014 Elsevier Ltd. All rights reserved.