IEA Ocean Energy Systems: Steady Progress Reported in 2025

The International Energy Agency's Ocean Energy Systems (OES) initiative has released its 2025 Annual Report, offering a comprehensive overview of developments across tidal stream, wave energy, ocean thermal, and salinity gradient technologies. According to the report, the sector continues to demonstrate 'steady progress,' with multiple prototype and pre-commercial projects advancing globally.

While ocean energy currently represents a small fraction of global renewable capacity compared to solar PV or wind, its potential for coastal and island communities is significant. Several IEA member countries are actively funding demonstration projects aimed at proving commercial viability and reducing the levelised cost of energy (LCOE) from marine sources.

The report comes at a time when the broader energy transition is accelerating, with governments and private investors seeking to diversify clean energy portfolios beyond established technologies. Ocean energy's predictability — particularly tidal power, which follows known lunar cycles — is seen as a key advantage over intermittent sources like solar and wind.

EU-level support through programmes such as Horizon Europe and the Ocean Energy Forum continues to play a crucial role in funding research and development. Analysts expect that with sustained investment and regulatory support, ocean energy could become a meaningful contributor to European grid resilience by the mid-2030s.