CNOOC (formerly Nexen)
Photo of CNOOC Headquarters,

The China National Offshore Oil Corporation Ltd. (CNOOC) is one of the largest oil and gas corporations in the world. CNOOC’s Canadian operations, formerly known as Nexen Inc, include assets in oil sands, fracked gas and offshore oil drilling throughout the country. The following case study emphasizes CNOOC’s Canadian operations only.

Why the top 50?

With stated plans to expand its operations in some of the most dangerous, emissions-laden energy sources, including shale gas, oil sands oil and deepwater oil, CNOOC has firmly established its role in the Top 50 as one of Canada’s major emitters.

Key Stats

Head office: Beijing, China

Locations of operation: North, Central and South America, Europe, Middle East and Africa, Asia Pacific22

Revenues: RMB 186.4 billion, the equivalent of C$36.1 billion23

Assets: RMB 617.2 billion, the equivalent of C$119.6 billion24

Reserves:4.96 billion boe25

Production: 1.288 million BOE (net oil and gas output)26

Memberships: Canada’s Oil Sands Innovation Alliance, Canadian Association of Petroleum Producers, Canadian Council for Aboriginal Business, International Association of Oil and Gas Producers, IPIECA, Petroleum Technology Alliance Canada


In Depth

CNOOC’s former Canadian brand, Nexen, grew out of a 1971 Canadian subsidiary of US-based Occidental Petroleum that operated under the name CanOxy for nearly three decades until changing to Nexen Energy in 2000.1 During this time Nexen’s holdings grew to include exploration and development sites in the North Sea, the Americas and Africa. Nexen was acquired by CNOOC in 2013 for C$15.1 billion,2 and in 2019 CNOOC removed the Canadian name, Nexen, from its subsidiary, rolling it under its own namesake.3 CNOOC is one of China’s three largest national oil companies and its largest producer of offshore crude oil and natural gas.4 CNOOC Ltd. is a listed subsidiary of CNOOC Group, which is a wholly state-owned enterprise.

Canadian Operations

CNOOC owns over 300,000 acres in the Athabasca region of Alberta where it mines for oil sands oil. One of its most significant oil sands operations is the Long Lake facility. In production since 2008, the Long Lake site produces synthetic crude oil through a multi-stage process, beginning with SAGD extraction. A 20 km pipeline connects the Long Lake facility to the Athabasca pipeline system, linking CNOOC’s crude to refineries across North America.5 CNOOC’s investment in Canadian shale gas began in 2006, making it an early entrant into BC’s shale gas industry. It has since accumulated a landholding of over 300,000 acres in the Horn River, Cordova and Liard basins of northeastern BC.6



Through its four-decade tenure as an oil sands producer, CNOOC has positioned itself as a key player in the lucrative development of energy resources in Canada. As a founding member of Canada’s Oil Sands Innovation Alliance—an industry association comprising the country’s top oil sands firms—and an early investor in BC’s shale gas industry, CNOOC (under its former name, Nexen) described itself as part of Canada’s energy “success story using technology, innovation and collaboration to grow Canadian oil and gas production and help supply the energy that fuels people’s lives.”7 This success includes ongoing investments—in both operations and public relations—in Canada’s carbon energy industries. Under the Nexen name, CNOOC marketed its investments in technology to reduce the amount of emissions released per unit of fuel produced as evidence that it is carrying out due diligence on climate action, Yet the company’s increasing total amounts of fuel produced negate such initiatives.8

CNOOC’s extended involvement in shale gas in BC and abroad also informs its attempts to market its position as an “ethical” oil company: like many companies involved in shale gas development, CNOOC specific language to “greenwash” shale gas as an “clean, safe and efficient energy system”9—rhetoric usually reserved for comparisons to other conventional sources like crude oil, and used to distract from the actual high carbon emissions derived from natural gas.10 Therefore, considering its extensive domestic and international holdings of conventional carbon energy, Nexen is well positioned to capitalize on both environmentally motivated and traditional consumer demand.

Meanwhile, CNOOC continues to make investments in its most carbon-heavy Canadian assets: in 2018, the company committed C$400 million to build a 26,000 barrel-per-day expansion to a steam-assisted gravity drainage (SAGD) facility at its Long Lake oil sands project in northern Alberta.11


In 2015, one of CNOOC’s pipelines at its Long Lake facility spilled 5 million litres of emulsion—a toxic mix of bitumen, wastewater and sand—36 km southeast of Fort McMurray, Alberta. The spill was one of the worst in Alberta’s history. After determining that the spill was caused by a design failure in the company’s pipes, the Alberta Energy Regulator charged CNOOC with five offences under the Environmental Protection and Enhancement Act and Public Lands Act.12 The double-walled pipeline that ruptured had been installed in 2014.13 The company pleaded guilty to the charges and was fined $750,000 in 2018 for damages.14

A month after the charges for its Long Lake spill, CNOOC reported another incident at its Long Lake facility. The Alberta Energy Regulator confirmed that 270,000 litres of produced water—a byproduct of oil and gas extraction—had spilled from a different pipeline.15

An explosion at CNOOC’s Long Lake facility caused the deaths of two Canadian employees on January 15, 2016. The employees were doing maintenance work on one of the company’s facilities when an on-site explosion occurred, killing one of the workers immediately and the other in hospital following the incident. CNOOC attempted to claim that the accident was the fault of the employees for doing work outside the scope of their approved tasks.16 CNOOC was charged for the deaths in late 2017, and it pled not guilty to both charges in March 2018.17 A verdict on the case has yet to be reached at the time of writing.

In September 2017, CNOOC and Japanese partner INPEX withdrew their proposal for a liquefied natural gas (LNG) facility on BC’s north coast. The C$28 billion project,18 first proposed in 2013,19 was one of nine LNG facilities slated to be built in order to accommodate the province’s burgeoning gas industry. The location of the proposed facility—Digby Island—is near Lelu Island, the site of a multi-year occupation by Indigenous peoples and allies who opposed the now-cancelled PETRONAS-backed Pacific NorthWest LNG facility.20 CNOOC cited the “macro-economic environment” associated with LNG development in BC as the cause of the cancellation.21

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  1. Globe and Mail, “Canadian Occidental Changing Name to Nexen Inc.,” Globe and Mail, September 28, 2000,
  2. “History,” Nexen, Internet Archive Wayback Machine, March 23, 2018,
  3. Jaremko, Deborah. “Nexen Name to Disappear as Subsidiary Absorbed into CNOOC International.” JWN Energy (blog), January 16, 2019.
  4. “Company Profile,” CNOOC Limited, accessedJune 14, 2019,
  5. “SAGD at Long Lake: How Long Lake Works,” CNOOC International, accessed March 18, 2019,
  6. “Assets,” Nexen, Internet Archive Wayback Machine, March 16, 2018,
  7. “Sustainability Report,” Nexen, Internet Archive Machine, March 23, 2018,
  8. “Climate Change” Nexen, Internet Archive Wayback Machine, August 18, 2018,
  9. “Gas and Power,” CNOOc, accessed June 14, 2019,
  10. James Wilt, “Canada Is Replacing Coal with Natural Gas—And That’s a Huge Problem,” The Narwhal, February 17, 2018,
  11. Canadian Press, “Nexen Announces $400M Expansion of Alberta Oilsands Project,” Global News, June 20, 2018,
  12. Emily Mertz, “5 Charges Laid against Nexen for Massive July 2015 Long Lake Pipeline Spill,” Global News, July 6, 2017,
  13. Mertz, “5 Charges Laid.”
  14. CBC News, “Nexen Fined $750,000 over Huge Long Lake Pipeline Spill near Fort McMurray,” CBC News, July 13, 2018,
  15. Canadian Press, “Nexen Reports 270,000-Litre Pipeline Spill of Produced Water in Northern Alberta,” Globe and Mail, August 15, 2018,
  16. CBC News, “A Year Later, No Answers after Nexen Explosion That Killed Two Workers,” CBC News, February 1, 2017,
  17. Canadian Press, “Nexen Energy Pleads Not Guilty in Oilsands Explosion That Killed Two Workers,” CBC News, March 14, 2018,
  18. Canadian Press, “Partners Pull Plug on Aurora LNG Project near Prince Rupert for Economic Reasons,” National Observer, September 14, 2017,
  19. Brent Jang, “CNOOC Heads Group Seeking to Export B.C. Liquefied Natural Gas,” Globe and Mail, November 29, 2013,
  20. Canadian Press, “Petronas-Backed Pacific Northwest LNG Megaproject in B.C. Cancelled,” National Observer, July 25, 2017,
  21. Canadian Press, “Partners Pull Plug.”
  22. “World Class Assets”, CNOOC, accessed June 18, 2019,
  23. CNOOC Limited, Annual Report 2017,
  24. CNOOC Limited, “Annual Report 2017
  25. “Company Profile,” CNOOC Limited.
  26. CNOOC Limited, “Annual Report 2017”