Companhia de Electricidade de Macau
Corporate brand
UnclaimedMacau's electricity utility, holding the territory's concession to transmit, distribute and sell electricity across high-, medium- and low-voltage networks.
Last updated August 31, 2026
AI crawler reads
No AI crawler has read this profile since Oct 28, 2026.
Overview
Companhia de Electricidade de Macau, commonly known as CEM, is a private public utility responsible for the transmission, distribution and sale of electricity in Macau. Its concession covers electricity supplied at high, medium and low voltage, making the company a central operator of Macau's power system rather than a conventional consumer-facing product brand. CEM also owns generation assets with an installed capacity reported at 408 megawatts. The company's role emerged from a change in Macau's electricity administration. From 1906 until 1972, electricity supply was managed by the Macao Electric Lighting Company Ltd., a business headquartered in British Hong Kong and now associated with Melco International Development. Following the former Portuguese administration's determination that the incumbent had not fulfilled its concession obligations, CEM replaced it in 1972. The company was subsequently restructured with the support of the Portuguese administration in 1982 and signed a 25-year concession contract in 1985. CEM's business combines power generation, grid operation, network dispatch, customer service and regulated utility administration. Its generation portfolio is based on two stations on Coloane Island: Coloane Power Station A, using low-speed diesel generation, and Coloane Power Station B, using combined-cycle gas-turbine technology. The Macau Power Station, an older facility with a history extending back more than a century, was officially decommissioned in 2016. The company operates a predominantly underground electricity network. The high-voltage system includes primary substations, customer high-voltage switching stations and hundreds of kilometres of 66 kV, 110 kV and 220 kV cables. Macau is interconnected with China Southern Power Grid through 110 kV and 220 kV cable links to substations in the neighbouring Zhuhai area. CEM also operates medium-voltage customer substations, low-voltage cables and a large street-lighting network. In November 2010, the Macau government and CEM agreed to extend the power supply contract by 15 years, with the revised terms taking effect on 1 December 2010. The extension reinforced CEM's long-term concession-based role in Macau's electricity sector. In 2014, Nam Kwong Group acquired a 90 percent interest in Sino-French Energy Development, an investment vehicle connected to CEM, and became the utility's largest shareholder through Nam Kwong Development (H.K.) Limited. The reported shareholder structure also includes Energy Asia Consultancy, Polytech Industrial, Asiainvest, the Macau government, China Power International Holding and other investors. CEM reports a strong reliability record. Its 2018 annual-report figures included an Average Service Availability Index of 99.9998 percent and a Customer Average Interruption Duration Index of 6.56 minutes, below the stated target of 20 minutes. The company has also adopted environmental, occupational-safety, quality, greenhouse-gas and information-technology management standards, including ISO 14001, OHSAS 18001, ISO 9001, ISO 14064 and ISO 20000 certifications reported in the reference material. CEM's activities remain focused on maintaining Macau's electricity infrastructure, integrating external power imports with local generation, and providing reliable utility service under its concession framework.
History
Macau's electricity supply was managed from 1906 to 1972 by the Macao Electric Lighting Company Ltd., which was headquartered in British Hong Kong. That company is identified in the reference material as the predecessor associated with what is now Melco International Development. In 1972, the former Portuguese administration replaced the operator after concluding that it had failed to meet the terms of its concession. Companhia de Electricidade de Macau emerged as the successor utility and assumed responsibility for Macau's electricity supply. CEM was restructured in 1982 with support from the Portuguese administration. Three years later, in 1985, it signed a 25-year concession contract. The concession gave the company a long-term institutional role in Macau's electricity sector and provided the framework for the development of its generation, transmission, distribution and customer-service capabilities. The reference material associates the period after the concession with improvements in cost-effectiveness and technology. A major contractual turning point came in November 2010, when CEM and the Macau government signed a 15-year extension to the power supply contract. The extension took effect on 1 December 2010 and continued the company's concession-based responsibility for supplying electricity in the territory. CEM's ownership structure has changed over time. Before 1987, the Macau government was the company's largest shareholder. The government subsequently reduced its holding, with the reference material reporting an 8 percent stake in the later shareholder structure. In 2014, Nam Kwong Group acquired 90 percent of Sino-French Energy Development from Sino-French Holdings (Hong Kong) and became CEM's largest shareholder through Nam Kwong Development (H.K.) Limited. The remaining interest in Sino-French Energy Development was associated with Stanley Ho at that time. Sino-French Energy Development was later merged with its direct parent, Nam Kwong Development, in 2019. The shareholder base reported in the reference material also includes Energy Asia Consultancy, Polytech Industrial, Asiainvest, the Macau government, China Power International Holding and other investors. China Power International Holding was associated with State Power Investment Corporation, formerly China Power Investment Corporation. CEM is not presented as a publicly listed company. Operationally, CEM developed a mainly underground network serving Macau's high-, medium- and low-voltage requirements. The high-voltage system includes 25 primary substations, eight customer high-voltage switching stations and approximately 953 kilometres of 66 kV, 110 kV and 220 kV cables. Interconnection with China Southern Power Grid is provided through two 110 kV and two 220 kV cable connections linked with substations in the Zhuhai area. The medium-voltage system includes 41 customer switching stations and 1,502 customer substations connected by roughly 2,294 kilometres of cable. The low-voltage network and street-lighting system add further extensive cable infrastructure, including approximately 11,105 streetlights. CEM's local generation assets are located on Coloane Island. Coloane Power Station A uses low-speed diesel generators, while Coloane Power Station B uses combined-cycle gas-turbine technology. The older Macau Power Station was officially decommissioned in 2016 after more than a century of operational history. The resulting system combines local generation with electricity imported through connections to the mainland grid. The company's reported 2018 reliability indicators included an Average Service Availability Index of 99.9998 percent and a Customer Average Interruption Duration Index of 6.56 minutes, compared with a stated target of less than 20 minutes. CEM has also reported adoption of international management systems covering environmental management, occupational health and safety, quality, greenhouse-gas management and information-technology service management. These certifications and reliability measures form part of the utility's stated emphasis on operational performance and sustainability.
- 2019
Sino-French Energy Development is merged into Nam Kwong Development
[1]Sino-French Energy Development is merged with its direct parent, Nam Kwong Development.
- 2016
Macau Power Station is decommissioned
[1]The historic Macau Power Station is officially decommissioned.
- 2014
Nam Kwong acquires the controlling interest in Sino-French Energy Development
[1]Nam Kwong acquires 90 percent of Sino-French Energy Development and becomes CEM's largest shareholder through its Hong Kong subsidiary.
- 2010
Fifteen-year concession extension
[1]The Macau government and CEM agree to extend the power supply contract by 15 years, effective 1 December.
- 1985
Twenty-five-year concession contract
[1]CEM signs a 25-year electricity concession contract.
- 1982
Corporate restructuring
[1]CEM is restructured with support from Macau's former Portuguese administration.
- 1972
CEM replaces the former concessionaire
[1]Companhia de Electricidade de Macau takes over Macau's electricity supply after the former operator is deemed not to have fulfilled its concession obligations.
- 1906
Macao Electric Lighting Company begins managing electricity supply
[1]The predecessor electricity operator begins managing Macau's electricity supply, a role it retains until 1972.
Products and positioning
Macau's concession-based electricity utility and principal operator of the territory's power transmission, distribution and supply infrastructure.
Utility network service
Electricity transmission
CEM operates Macau's high-voltage transmission infrastructure, including 66 kV, 110 kV and 220 kV cable systems and primary substations. The network is connected to China Southern Power Grid through links with substations in the Zhuhai area, allowing Macau's electricity system to combine local generation with imported power.
Utility customer service · 1972
Electricity distribution and supply
CEM distributes and sells electricity to customers at high, medium and low voltage. Its distribution assets include customer switching stations, medium-voltage substations, low-voltage cables and connections serving residential, commercial and industrial users throughout Macau.
Electricity generation
Coloane Power Station A
Coloane Power Station A is one of CEM's two reported active generation facilities on Coloane Island. It uses low-speed diesel generator technology and forms part of the local generation capacity supporting Macau's electricity system.
Electricity generation
Coloane Power Station B
Coloane Power Station B is a CEM generation facility on Coloane Island using combined-cycle gas-turbine technology. It contributes to the company's reported installed generation capacity and complements electricity imported through the mainland interconnection.
Public utility infrastructure
Street-lighting electricity service
CEM operates Macau's street-lighting network as part of its broader electricity infrastructure responsibilities. The reported system includes approximately 571 kilometres of cable and about 11,105 streetlights.
Brand decisions
2016
Retire the Macau Power StationGeneration changeBackground
The Macau Power Station had a history of more than 110 years and was part of the territory's older generation infrastructure.
Action taken
CEM officially decommissioned the Macau Power Station.
Aftermath
CEM's reported active generation portfolio centered on the two Coloane Island stations, while mainland interconnections supported the wider system.
2014
Change in the largest shareholderM&ABackground
CEM's investment structure included Sino-French Energy Development, whose majority ownership was held through Sino-French Holdings.
Action taken
Nam Kwong acquired a 90 percent stake in Sino-French Energy Development through Nam Kwong Development (H.K.) Limited.
Aftermath
Nam Kwong became CEM's largest shareholder. Sino-French Energy Development was subsequently merged into Nam Kwong Development in 2019.
2010
Extend the Macau power supply concessionStrategyBackground
CEM's existing concession-based role required a long-term contractual framework to continue supplying Macau.
Action taken
CEM and the Macau government signed a 15-year extension to the power supply contract in November 2010, with the new terms taking effect on 1 December 2010.
Aftermath
The extension continued CEM's role as Macau's principal electricity transmission, distribution and supply utility.
Sources1 sources
Cite this profile: Cite the canonical profile. /brand-wiki/companhia-de-electricidade-de-macau · Editorial policy · How profiles are compiled