Companhia de Electricidade de Macau - CEM, S.A. (CEM) is a public utility company with the sole concession to transmit, distribute and sell high, medium and low-voltage electricity in Macau. CEM also owns power generation facilities.
The Macau electricity transmission network comprises 25 primary substations, 8 customer high-voltage switching stations and 953 kilometres of 66kV, 110kV and 220kV high-voltage cables. The Macau electricity network is connected with China Southern Power Grid via two 110kV cables and two 220kV cables. The two 110kV cables are connected to Gongbei Substation and Nanping Substation, while the two 220kV cables are connected to Zhuhai Substations and Qinyun Substation.
The 11kV medium-voltage electricity transmission network comprises 41 customer switching stations and 1,502 customer substations (11kV/400V) connected by cables with a total length of 2,294 kilometres. The low-voltage transmission network is made up of 906 kilometres of cable, while the street lighting network comprises 571 kilometres of cable and about 11,105 streetlights. The power network of CEM is almost entirely comprised of underground cables.