Preliminary measurements of thermal and visual conditions in shopping malls in Hong Kong

We present electricity use in the commercial sector in Hong Kong during the 30-year period from 1970 to 1999. The average annual growth rate was 9.1% during the past three decades. Commercial buildings, especially shopping centres, are major electricity end-users. A survey often fully air-conditioned shopping centres built during the 1980s and 1990s was conducted to establish the typical indoor thermal and visual conditions. The measured conditions were compared with established international thermal comfort and lighting standards. Two aspects were found to have energy saving potential, namely inside air temperature and daylighting. Although about 90% of the measured thermal conditions complied with the ASHRAE comfort zones, it was found that the summer conditions tended to be 1-2°C lower that the 25.5°C/55% relative humidity recommended for local air-conditioned commercial premises. This paper presents the findings and discusses the energy implications.