Performance assessment of district cooling systems for a new development district at planning stage

Abstract

A district cooling system supplies cooling to a group of buildings in a district. It has been widely used for its high energy and economic performance, especially in Asian and European countries. It is supposed that a district cooling system can achieve good performance when used in the subtropical area like Hong Kong, where the cooling is required throughout the year and the building density is very high. This study aims to quantitatively assess the performance of the district cooling system in a new development area in Hong Kong. By modeling the buildings and cooling systems of the new district based on the current plan, the performance of district cooling system is compared with the conventional cooling system, which refers to individual in-building cooling systems. Three cases with different chilled water systems are simulated and analyzed. Results show that the district cooling system is more efficient than the individual cooling system, with less energy consumption and operational cost. Energy consumption of main subsystems is compared and the energy saving potential of district cooling system is analyzed. Sensitivity study of district cooling system performance at partial load is conducted and results show that the district cooling system is more efficient under different load conditions during night time.