Introduction

Buildings account for about 90 per cent of total electricity consumption in Hong Kong. By improving building energy efficiency, greenhouse gas emissions would be effectively reduced. The Buildings Energy Efficiency Ordinance aiming to improve building energy efficiency has been fully implemented since September 2012. With the development of energy saving technologies, the Electrical and Mechanical Services Department (EMSD) would keep the building energy efficient requirements abreast of the times. The latest 2021 edition of the Building Energy Code (BEC) has improved the overall building energy efficiency by over 23% as compared with the 2012 edition. It is expected the energy efficiency of the BEC could be further increased by 10% before 2035. For example, the energy retrofit of central building services equipment that comply with BEC 2012 edition could achieve up to 23% energy savings according to the latest edition of BEC. Further energy savings could be achieved for retrofitting equipment that comply with older BEC editions. Given the recent rising energy and power generation costs, building energy efficiency retrofit can effectively reduce building energy consumption, which would be one of the most effective means to offset the rising energy costs.