Subsea power cables face unique dangers ranging from physical damage on the ocean floor to complex legal hurdles when passing through different countries’ waters, according to the authors of the newly released report. These massive projects are particularly vulnerable to shortages in specialized ships and technical equipment, which can lead to significant construction delays and soaring costs.
The report states that “operational risks are higher for subsea cables compared to overhead lines” because they can be “damaged by natural events such as seabed movements, underwater landslides, or strong currents, and by third-party activities including anchor drags, fishing trawlers or dredging operations.” The authors also warn that for “lengthy subsea projects, the cable route may pass through territorial waters of a third country, which further increases permitting and political complexity.”
In simple terms, building and maintaining these underwater cables is far more difficult than traditional power lines because they are hidden deep beneath the waves and hard to reach. While a line on land can be fixed in a few days, a damaged subsea cable requires specialized repair ships that are currently in very short supply worldwide, meaning a single accident could shut down power trading for months. Additionally, because the cables often cross international maritime borders, developers must navigate a maze of different environmental rules and political tensions between neighboring nations.
The report “Financing the ASEAN Power Grid” was published by the International Energy Agency in Paris in March 2026. Lead author James Bragg and a team of analysts provide a comprehensive framework for unlocking the capital required to build a more integrated and sustainable energy future for Southeast Asia.
