ExxonMobil Pushes to Prolong Output at Angola’s Block 15

Angola’s Block 15, one of the country’s key offshore oil assets, is entering another phase as ExxonMobil looks to keep production going for longer.

ExxonMobil has awarded an engineering, procurement, construction, and installation (EPCI) contract to the Subsea Integration Alliance (SIA), with Subsea7 announcing the deal on April 30. The contract covers the Redevelopment 2.0 Likembe project, aimed at getting more out of a field that has already been heavily produced. SIA—a partnership between SLB OneSubsea and Subsea7—will handle subsea tie-backs, linking new wells to existing infrastructure on Block 15. The contract ranges between $150 million and $300 million, and rather than building new platforms, ExxonMobil is using existing infrastructure to manage costs while maintaining output.

Teams across Subsea7’s offices in Paris, Luanda, Lisbon, and Sutton will manage the project, while SLB OneSubsea will manufacture subsea control systems in Norway, including cables used to power and manage seabed equipment. Subsea7 says the project draws on experience from work in West Africa, Australia, and the United States, with a focus on safety and local skills development in Angola.

Current state of Block 15

ExxonMobil has operated Block 15 since 1994, and it remains one of Angola’s most important offshore assets. The block includes 19 commercial discoveries, with recoverable resources estimated at around 3 billion barrels, of which about 2.5 billion barrels have already been produced since operations began in 2003. The field has moved into a later stage of its life, with key areas such as the Kizomba fields estimated to be around 85% depleted, meaning production now depends more on continued drilling and optimisation than on new discoveries.

At its peak, Block 15 produced over 600,000 barrels per day, supported by four floating production units: Kizomba A, Kizomba B, Mondo, and Saxi-Batuque. In November 2025, ExxonMobil secured an extension of its operating license through 2037 after discussions with the Angolan government.

This investment is part of Angola’s effort to slow declining oil output. Since leaving OPEC in 2023, the government has aimed to keep production above 1 million barrels per day, with oil still central to the economy. According to the IMF, more than three-quarters of economic activity depends on the sector, with crude prices influencing about 83% of GDP.