A case study on existing building HVAC system optimization of a five-star hotel in Shanghai

Abstract

Due to the complex interaction of components and the improper O and M in existing building HVAC system, a large amount of HVAC systems is not able to operate as their design condition. In order to improve the HVAC energy performance, the common methods are renovation and commissioning, and these days, commission is getting attention due to its efficiency and low cost. This paper aims to illustrate the existing building optimal method and its effects. A five-star hotel is used as example, and after field study, several optimal methods were applied, including improving performance of main chiller by applying a boost pump to the inlet pipe of evaporator, adjusting chilled water hydraulic balance and shutting down the chilled water bypass, adding free-cooling system, adjusting the pump frequency and air-conditioning terminal. The result shows that after the whole optimization, from the theoretical analyzation, the system can save about 319,200 kWh per year, according to the energy bill, the final energy saving is 359,000 kWh per year, and performance of building system and indoor thermal comfort are significantly improved.