Cooling demand constitutes a large portion of total electrical demand for office buildings during peak hours. Ice storage technology can help shift this peak cooling demand to off-peak periods. This research analyzes the chiller energy consumption of conventional non-storage and ice storage cooling systems for large and medium-sized office buildings in diverse climate zones. Demand Response Quick Assessment Tool (DRQAT) has been used to model and simulate large and medium-sized office buildings. The construction and weather files in DRQAT have been modified to incorporate construction standard and weather data for the cities representing the diverse climate zones. Results indicate that the chiller energy consumption for non-storage and ice storage systems depends highly on climatic conditions. Climate zones with hot summers as well as small day and night temperature variations show higher chiller energy consumptions. The marine climate zone has the lowest chiller energy consumption. The cold/humid climate zone has higher chiller energy consumption than the cold/dry and very cold climate zones. The cold/dry and very cold climate zones have comparable chiller energy consumption. Research findings as presented in this paper will help utilities and building owners to quantify the benefits of installing ice storage systems in office buildings located in different climatic conditions. (C) 2012 Elsevier B.V. All rights reserved.