Establishing energy consumption benchmarks for commercial complexes in Hong Kong

It is difficult to properly assess whether energy has been used efficiently and effectively in a commercial building that is equipped with a central air-conditioning system and houses a mix of premises of largely different energy characteristics. Due to the inter-relationship between the energy use of individual tenants and of the central air-conditioning system, a building that consumes a large amount of energy may not be inefficient if a substantial portion of its area is occupied by premises that have intensive cooling requirements. The paper describes a proposed method for establishing energy consumption benchmarks for assessing the energy performance of this type of buildings, which are the dominant energy consumers in Hong Kong. The key feature of the method is that the benchmarks to be established would be specific to each individual building, dependent on the mix of premises in the building and an those characteristics of the building and its air-conditioning system that are unlikely to be changeable in the interest of reducing energy use. The energy consumption benchmarks would need to be established from an energy end-use database for commercial buildings, including energy end-uses of the central services systems and in various types of premises in commercial buildings.