Southeast Asia is embarking on a new wave of deepwater gas developments aimed at unlocking roughly 28 trillion cubic feet of resources, though fragile project economics and execution risks could test the region's ability to deliver, Wood Mackenzie strategists said in a note on Monday.
Wood Mackenzie said the projects are expected to require more than $20 billion in investment by 2030, as governments and operators seek to offset declining output from maturing shallow-water and onshore fields.
"Southeast Asia's shallow-water and onshore gas fields are maturing rapidly, and this necessitates a focus on deepwater resources that were once considered too risky and expensive," said Munish Kumar, senior research analyst at Wood Mackenzie.
The investment, spanning Indonesia, Malaysia and Brunei, marks what Wood Mackenzie describes as Asia's "Deepwater 2.0" phase, following an earlier wave of projects between 2008 and 2017.
The deepwater projects established commercial viability but failed to sustain momentum due to regulatory, geological and commercial hurdles, the consultancy said.
Wood Mackenzie analysts said the renewed focus comes amid growing energy security concerns.
Indonesia's non-associated offshore gas production has fallen more than 12% from its 2018 peak, while Brunei will need an additional 500 million cubic feet per day of supply after 2030 to maintain liquefied natural gas exports.
Malaysia is also increasing its reliance on offshore developments, with deepwater output projected to account for about 20% of its gas production by 2027.
Wood Mackenzie said major developments include the North Ganal, Rapak, and Ganal projects in Indonesia's Kutei Basin, the South Andaman fields in North Sumatra, Kelidang in Brunei, and the Rosmari-Majoram project in Malaysia.
"These projects will deliver critical gas supply into domestic markets and LNG export plants to replace declining legacy production," said Kumar.
Operators include global energy majors, such as Italy's Eni and Shell, alongside national oil firms like Malaysia's Petronas and Abu Dhabi's Mubadala Energy, which is entering deepwater development in the region.
However, despite most projects' strategic importance, Wood Mackenzie said they offer internal rates of return of about 15% under base-case assumptions, which are lower than those of comparable deepwater developments globally.
Project economics are highly sensitive to cost overruns, pricing and delays. The consultancy said a 20% rise in capital expenditure, or a similar drop in gas prices or output, could wipe out around 150% of the project's value, while a three-year delay could halve returns.
"Without progressive fiscal mechanisms to share risk, there's virtually no cushion for execution failures," Kumar said.