Int. J. Exergy, Vol. x, No. x, xxxx 1 Copyright © 200x Inderscience Enterprises Ltd. Energy and exergy analyses of a residential cold thermal energy storage system Canan Acar* and Ibrahim Dincer Faculty of Engineering and Applied Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario, Canada, L1H 7K4 Email: Canan.Acar@uoit.ca Email: Ibrahim.Dincer@uoit.ca *Corresponding author Abstract: In this study, a practical ice – slurry thermal energy system is considered to meet a building’s cooling demands. Hourly system analyses are conducted, including total work and heat loads, rate of exergy destruction, exergy efficiency and COP. The effects of varying ambient conditions on the charging, storage, and discharging periods are also investigated. Exergy destruction and exergy efficiency concepts are studied to consider irreversibilities to address the consequences of non-conservation of exergy. Focusing at different times, cooling demands, and identifying the exergy efficiency and destructions at charging at discharging periods and the system’s exergetic performance give an idea about ‘the availability of work’ lost in different subunits and at different ambient temperatures. The results show that during the peak cooling demand of the residential unit, the rate of exergy destruction is about 64 kW, the exergy efficiency is about 47%, and the highest COP becomes about 2.45, respectively. Keywords: CTES; cold thermal energy storage; off-peak cooling; energy; exergy; environment; efficiency. Reference to this paper should be made as follows: Acar, C. and Dincer, I. (xxxx) ‘Energy and exergy analyses of a residential cold thermal energy storage system’, Int. J. Exergy, Vol. x, No. x, pp.xxx–xxx. Biographical notes: Canan Acar is a PhD Candidate at UOIT and a member of Dr. Dincer’s group, where she conducts research on photoelectrochemical hydrogen production since September 2012. For her Master’s, as a research assistant at Illinois Institute of Technology in Chicago, she developed and tested complex metal hydride based hydrogen storage systems. After her Masters, she worked as a sustainability consultant in Chicago where she focused on waste management/material conservation. Ibrahim Dincer is a Full Professor in the Faculty of Engineering and Applied Science at the University of Ontario Institute of Technology in Oshawa, Canada. He has chaired many national and international conferences, symposia, workshops and technical meetings. He has delivered many keynote and invited lectures. He is an active member of various international scientific organisations and serves as Editor-in-Chief, Associate Editor, Regional Editor and Editorial Board Member on various prestigious international journals. He is a recipient of several research, teaching and service awards.