Towards to sustainable energy-efficient city: A case study of Macau

The dependence of cities on intensive energy consumption is a major cause of climate disruption, and there is increasing interest in the potential for many cities to facilitate a transition to sustainable energy utilization. This study, taking Macau as a case study, reviewed its energy consumption and the efforts that have been made to promote the building of a sustainable energy-efficient city. The results revealed that energy consumption in Macau has increased steadily over the past twenty-five years from 16,295 TJ in 1990 to 34,612 TJ in 2015. In order to improve energy efficiency, the Macau government enacted some effective policies and guidance, and also launched some energy-saving publicity campaigns. Survey results showed that both Macau residents and the commercial sector had good energy-saving awareness, and that energy-saving behaviors were very common. There has been a consequent reduction in unit energy consumption in Macau: the energy consumption per capita declined from a peak value 67.20 GJ in 2005 to 53.23 GJ in 2015. The two keys for achieving a sustainable energy-efficient city-energy efficiency in buildings and in the transportation system-have also been greatly improved. The unit energy consumption of office buildings decreased from 56.7 MJ/m2/year in 2005 to 36.3 MJ/m2/year in 2013. Improving and promoting public transit has been the main approach to attaining transportation energy efficiency in Macau. In addition, electricity generation from waste incineration has become an important electricity source in Macau, accounting for 17.4% of the local electricity generation in 2015. Macau has chosen roof-top solar technology as the most effective way to utilize solar energy, as a 1-m2 solar panel can generate about 167 kWh of electricity annually. It is hoped that this study can provide useful information to help Macau, as well as other cities, to become a sustainable energy-efficient city.