Electricity sector in Macau is regulated by its electric power utility company Companhia de Electricidade de Macau (CEM), established in 1972 during the Portuguese rule.
CEM's generation facility consists of three power stations. One located in the Macau peninsula: Macau Power Station (CMC). Two on Coloane Island: Coloane A Power Station (CCA) and Coloane B Power Station (CCB). Together, CEM has a total installed capacity of 472 MW.
The predominant types of generation technology deployed are the low speed diesel generator using heavy fuel oil for CCA and the combined cycle gas turbine using natural gas for CCB.
In 2012, CEM produced 376 GWh to supply 8% of Macau's 4,344 GWh gross energy demand, while the remaining 3,968 MW (92%) was imported from Mainland China through Guangdong Power Grid under China Southern Power Grid Company. In 2013, CEM generated 7.2% electricity for Macau, while the electricity import from Mainland China rose to 92.8%.
The Macau electrical transmission network comprises 20 primary substations with a total installed capacity of 1,260 MVA in 220/110 kV, 1,500 MVA in 110/66 kV and 1,752 MVA in 66/11 kV.
As of December 2012, the high voltage transmission network consists of 281 km line made up of 220 kV, 110 kV and 66 kV cables. The 11 kV medium voltage distribution network is composed of 35 switching stations and 1,245 customer substations (11/0.4 kV) connected by cables with a total length of 617 km. The low voltage distribution network is made up of 780 km of cables. Almost all CEM's power network is constituted by underground cables which mainly come from Europe, United States and South Korea.
Electrical grid in Macau has been linked to electrical grid of Guangdong since 1984.
In 2015, CEM announced that over the next three years, CEM will build another five new substations to power up the upcoming Macau Light Rail Transit, hospitals and Ilha Verde.
Macau has also interconnection grids with Mainland China in Guangdong with Guangdong Power Grid of the China Southern Power Grid Company.
The first interconnection commissioned in June 2008 are the three 220 kV circuits connected at the 220/110 kV Canal dos Patos substation, with the importation capacity of 1,050 MVA. The second interconnection commissioned in June 2012 are the two 220 kV circuits connected at the 220/110 kV Lotus substation, with the importation capacity of 700 MVA. These five interconnection circuits give a total of 1,750 MVA importation electric capacity for Macau from Guangdong in Mainland China.
Macau has been experiencing an average 8.5% annual growth rate for their electricity demand. Their maximum daily electricity demand is 756.7 MW. Macau's utility frequency is 50 Hz and at 400 V (three-phase) and 230 V (single-phase).
By the end of 2007, CEM was providing electricity to 211,238 customers, in which 75% of them are in the Macau Peninsula, while the remaining 21.9% are in Taipa and 3.1% in Coloane. Electricity reaches every individual in Macau.
CEM's power supply reliability maintains at world leading performance. The Average System Availability Index (ASAI) reached 99.9998% in 2010. In 2014, the System Average Interruption Duration Index was as low as 1.34 minutes. CEM has five mobile equipment units as contingency measures to deal with electricity blackouts. All of the underground installed cables undergo regular routine inspection and diagnosis every five years.
CEM has established and implemented an Integrated Management System with all three Management System Certifications ISO 9001, ISO 14001 and OHSAS 18001. CEM was the first public utility company in Macau and the first power company in Hong Kong and Macau to obtain the certification ISO 14064-1 Greenhouse Gases Management System by taking systematic and genuine actions against greenhouse gases emissions.
In order to cope with the growing concern on environmental issues, CEM has invested more than MOP 450 million to improve CEM environmental performance, including investment in Selective Catalytic Reduction Systems, Natural Gas Conversion, Air Quality Monitoring Systems, Scrap Yard, Noise Control Facilities etc.
Every year, CEM holds fire alarm and evacuation drills at different locations of its premises to test and evaluate the effectiveness of their contingency plans, further enhance the emergency response abilities of all the participating staffs and ensure the safety of the employees and facilities.