Performance and benefits of distributed energy systems in cooling dominated regions : a case study

Abstract

The distributed energy system (DES) is an innovative energy system with high energy efficiency and economic benefits. However, the application of this energy system in cooling dominated regions is still not well studied yet. This paper aims to investigate the performance and benefits of the DES in Hong Kong. Based on the characteristic of energy demands, a DES, which integrates distributed generations and district cooling systems, is designed. The chilled water distribution networks and the pumps systems are determined by the cooling demand. An optimal design approach is adopted in equipment sizing of the DES. Based on the modeling results, the hourly energy consumptions of the DES and the CES (centralized energy system) are compared. In the DES, the grid load is reduced significantly, and the cooling system operates with a higher efficiency during the most period of the year. The primary energy saving and the cost saving of the DES are analyzed and discussed. Results denote that the DES can achieve a primary energy saving of 9.58%. Even the capital cost becomes higher, the DES is also economically beneficial due to the low operation cost.