Introduction

In 2026, the IEA-OES marks its 25th anniversary, offering an opportunity to reflect on how the collaboration has grown from its early beginnings into a recognised international platform for cooperation and knowledge sharing in ocean energy.

Launched in 2001 under the framework of the International EnergyvAgency, IEA-OES was established by its inaugural signatories — Denmark, Portugal and the United Kingdom — with Ireland and Japan joining soon afterwards. Over the years, the collaboration has continued to expand most recently with Brazil formally joining on 13 April 2026, further strengthening the programme’s international reach in its anniversary year. The collaboration now has a total of 22 member countries and the European Commission.

Created to advance the research, development and demonstration of ocean energy technologies, IEA-OES has evolved alongside the sector itself, adapting to new challenges and opportunities over time. Today, it brings countries together to share knowledge, develop joint studies and guidance, support policy and regulatory dialogue, strengthen environmental understanding, and accelerate the viability, uptake and acceptance of ocean energy in an environmentally responsible manner. In doing so, IEA-OES continues to play an important role in supporting the global clean energy transition and in shaping the long-term development of ocean energy worldwide.