On the role of building use and operational strategy in integrating ice storage systems: an economic perspective

Abstract

Ice thermal energy storage has been widely used in different types of building to manage cooling peak loads. In the present study, technical and economic feasibility studies have been performed to evaluate the effect of building use and storage strategy on integrating ice storage. Four different building uses, namely residential, office, educational, and commercial; and nine storage strategies are investigated. For each building type and storage strategy, the hourly cooling load is simulated for a typical day in each month. The appropriate cooling system is then selected and analyzed in terms of energy consumption. The additional capital required to install ice storage and the potential savings obtained by shifting the cooling load from peak to off-peak hours using this installation are estimated to assess the economic feasibility of integrating the storage system. The results show that although the energy consumption in systems with ice storage is generally higher than that in a conventional system, the annual energy costs can be up to about 50 % lower with appropriate storage strategies, albeit at the expense of a higher initial investment. It is also shown that building use and storage strategy significantly impact the economic feasibility of integrating ice storage into building cooling systems. Comparing four building types, the use of an ice storage system in residential buildings is much less economical due to the presence of 24-h cooling loads, so the payback period assuming an electricity tariff of 20¢ and considering the best storage strategy is more than 7 years, which is 62, 66 and 73 months more than the payback period for the office, commercial and educational buildings, respectively. Therefore, implementing different policies for residential and non-residential buildings is recommended to encourage the use of cold storage systems in the building sector.