Macao, 5 July 2012
Since CEM’s 220kV Canal dos Patos Substation was put into service in 2008, Macao’s economy has been growing at a rapid pace. With GDP increased by 74% during the period, the total energy consumption in Macao increased by 15% from 3,475 GWh in 2008 to 4,002 GWh in 2011.
Owing to the surge of oil prices and the undersupply of natural gas, Macao still largely depends on importation for the power supply. In 2011, 79% of the total power consumption in Macao was imported from the Guangdong Power Grid Corporation (GPG). To cope with the increase in power demand and improve the reliability of power supply from Guangdong, CEM spent MOP 424 million to build the second 220kV interconnection connected with GPG. Located between Cotai Strip and Heng Qing Island, the interconnection includes a 26km cable backbone, the Lotus Substation and two 350MVA transmission cables. Under the N-1 safety standard, the importation capacity is substantially increased to 900MVA. It will effectively improve the reliability of power supply from the China Southern Power Grid Co. Ltd. and the stability of electricity prices.
At present the new interconnection is undergoing testing. To ensure the smooth operation of the network, the Power and Networks Dispatch Department of CEM, together with Guangdong Power Dispatch Centre of GPG, and Networks Dispatch Center of Zhuhai Power Supply Bureau, conducted a joint emergency drill at the end of June. The objective of the drill is to test the emergency response ability of and the cooperation between the three parties in the case of an accident, and to test their dispatchers’ understanding and familiarity in term of the operation of the network and relevant control measures under the existing operation environment.
The drill simulated a situation that the power supply through all five 220kV cables connecting Macao and Guangdong’s power grid was totally interrupted and could not be restored in a short time, and the power supply of all CEM’s power stations was suspended at the same time. Under such situation, the 110kV stand-by interconnection connecting Guangdong and Macao was initiated, and later CEM’s power stations resumed their operation. When the 220kV interconnection was repaired, the power supply was switched to the 220kV interconnection, and the operation of Macao’s power supply network got back to normal.
The three parties all agreed that the drill tested their dispatch centers’ understanding of and familiarity with the operating environment of existing power supply networks and relevant control measures. They believed the drill achieved their objectives and further enhanced their confidence in providing reliable power supply to Macao.