Study on Energy Consumption Ration for Office Buildings

Abstract

Energy management of public buildings is the key point for energy efficiency in China. Energy consumption ration (ECR) serving as an energy benchmark is one of the useful baselines to promote building energy efficiency diagnosis, and how to determine reasonable ECRs is an issue of the utmost importance. In this paper, the mean value method, the factor normalization method and the cumulative frequency distribution method were proposed firstly to determine ECR. In the factor normalization method, ECR is defined as the maximum value of energy use intensity by regulating the value of each explanatory factor within its scope. Twenty office buildings in Shanghai were selected for case study. Detailed energy audits and on-site surveys were conducted to obtain building information, operation and energy use data. Based on the survey data, the ECRs under the proposed three methods were compared, and the ECR determined by the factor normalization method is approved to be reasonable and practicable. In addition, it is found that three dependent variables, i.e. gross floor area, building usage rate and having data center or not, play a big role in the office building energy consumption. The ECR for office buildings in Shanghai is determined to be 60.3 kgce/(m2.a), and only 20% of the samples have higher energy use intensities than the fixed ration. It is suggested to use the factor normalization method as an efficient method to determine ECR, which can also shed some lights on the determination of ECRs for other buildings.