Embodied energy assessment for Macao's external trade

As a typical heterotrophic city, Macao's economic boom is fueled by external trade, which provides Macao with not only direct energy products in forms of oil, gas and electricity, but also indirect energy embodied in other imports. However, the prevalent studies on Macao's energy issues are confined to direct energy inputs. Based on the most recent trade statistics and embodied energy intensity databases, a comprehensive assessment of energy embodied in Macao's external trade after its sovereignty handover is performed. The results show that Macao's embodied energy consumption is over 2 times as that of direct energy consumption. The net embodied energy transfer via external trade from other regions to Macao increased from 6.31E+7 GJ in 2000 to 8.75E+7 GJ in 2011, while the embodied energy intensity dropped sharply from 1.02E+04 GJ/ million USD to 2.40E+3 GJ/million USD in the same period. Non-energy-products and services rather than energy products play the key role in energy transfer, indicating that indirect energy dominates Macao's embodied energy consumption. The largest energy imbalance happens between Macao and mainland China. Given the nature of Macao's economy and escalating socio-economic development, it is suggested that the invisible but dominant indirect energy consumption by Macao should be addressed by decision makers and included in future development strategies.