A study of residential energy use in Hong Kong by decomposition analysis, 1990–2007

Energy end-use for all sectors (commercial, residential, transport, industrial) in Hong Kong shows that the residential share increased from 14.2% in 1990 to 18.1% in 2007, such share increase has prompted the authors to analyze the issue. The Divisia decomposition analysis is used to evaluate the respective contributions of changes in (1) the number of households, (2) share of different types of residential households, (3) efficiency gains, and (4) climate condition to the energy use increase. The analysis reveals that the major contributor was the increase of the number of households, and the second major contributor was the intensity effect. As expected, the segment of the private housing (apartments) was becoming less energy efficient. In addition, it is interesting to note that the energy end-use per household in the segment of government rental subsidized housing (apartments) was decreasing. The decrease of the household income in this segment may be one of the reasons while statistics showing that the number of low-income household was increasing and leaning towards the lowest income classes. On the other hand, it is believed that people tend to consume more energy to obtain a quality life characterized with comfortable living with the growth of economy and improvement of living standard. However, Hong Kong becomes a counterexample since 2004. Therefore, changing the residents’ behavior may not be an effective tactic for reducing energy consumption.