Power consumption modeling and energy saving practices of hotel chillers

Hotel buildings consume a significant amount of energy, especially their chiller systems. This study aims to create a model of the power consumption of the hotel chillers, and to identify the practical means to reduce the power usage of chillers. The examined parameters include air-conditioned floor area, guest floor area, gross floor area, number of employees, room occupancy, food cover, outdoor air temperature, window velocity, service type and relative humidity. It is anticipated that the developed modeling equation may provide a reference for hotel engineers to forecast any diagnostic problems and form a benchmarking indicator for comparing chillers’ energy efficiency. A survey of hotels in Shanghai was carried out to collect energy consumption data of chillers during air-conditioned cooling months. Regression analysis indicates that number of staff was a major and statistically accepted factor in explaining the electricity consumption of chiller in hotels. In addition, the paper discusses some means and suggestions in reducing chillers’ power consumption.

► The number of hotel employees and outdoor temperature are the statistically significant and strongly correlated variables that affected the energy consumption of chillers.
► A generic modeling equation was established to create a benchmark for comparing the electricity consumption of chillers in hotels.
► We identified four approaches in lowering the electricity consumption of chillers, namely, condensing temperature control, optimal loading computation, unequally sized chillers, and variable speed control.