Southeast Asia plans five subsea power cables by 2040, Ember says governance is the real hurdle

Southeast Asian countries are planning five subsea power cable projects as part of a broader push to expand regional grid interconnection by 2040. Energy think tank Ember says the main challenge is not the cable technology itself but the lack of cross-border planning, cost-sharing standards, and marine governance frameworks. The ASEAN Interconnection Masterplan Study III calls for 18 new and existing interconnectors to more than double regional capacity from 7.7 GW. Ember identifies three core tasks: setting up a regional joint planning system, agreeing on cost-sharing rules, and creating a marine governance framework to handle overlapping territorial seas, EEZs, shipping routes, and fishing grounds. The Philippines already uses HVDC technology for domestic island links. Analysts say success depends on building cooperation systems, not just laying cables.