Feasibility of lowering the condenser's inlet water temperature of a chiller using thermal water storage

A novel approach is proposed for applying cool thermal storage to reduce th e on-peak demand of a water-cooled chiller. By charging the store at night via a cooling tower, and using this water to supply the condenser of a chil ler during on-peak hours, cooler than normal water is supplied to the chill er. A feasibility study of this system was conducted using TRNSYS - a trans ient simulation modeling program examining varying capacities of cooling to wer and thermal store volumes. These systems were tested using geographic w eather data that demonstrated conducive diurnal changes in wet-bulb tempera ture (T-wet). Results suggest that the use of cool water thermal storage in this way can reduce both on-peak energy demand and on-peak power use by as much as 35%, System optimization is dependent on the thermal storage effic iency, the capacity of the cooling tower, and the diurnal change in T-wet,. (C) 2000 Elsevier Science Ltd. All rights reserved.