About Annex IV

Annex IV is a collaborative project among member nations of the IEA Ocean Energy Systems (OES) to examine environmental effects of ocean energy devices and projects. There is currently a wide range of ocean energy technologies and devices in development around the world; the few data that exist on environmental effects of these technologies are dispersed amongst different countries and developers. The U.S. led the Annex IV effort; the Department of Energy (DOE) was the Operating Agent for Annex IV, working with federal partners the Bureau of Ocean Energy Management (BOEM) and the National Oceanic and Atmospheric Administration (NOAA). The Annex IV program includes the following activities:


Phase 1: 2010-2012

Annex IV member countries collaborated to create a searchable, publically available database of research and monitoring information to evaluate environmental effects. The database includes data from ocean energy projects and research studies and case study reports compiled as part of this effort. Annex IV addresses wave, tidal and ocean current energy development, but not ocean thermal energy conversion (OTEC) or offshore wind. Two international scientific workshops were held to provide input for the database and to inform the Final Annex IV Report, a worldwide focus on monitoring and mitigation methods including case studies from the database and lessons learned from the project.


Phase 2: 2013-2016

The success of the Annex IV program warranted a second phase to continue and expand efforts. Phase 2 will primarily focus on updating and expanding the database of metadata forms, writing a state of the science report in 2016, and creating a community of experts intent on collaboration for the advancement of the industry. This community will be encouraged with several workshops, quarterly webinars, hosting an international conference, ability to comment and rate documents on Tethys, and Tethys social media.


Countries Currently Involved in Annex IV (13)

For More Information:


Annex IV Metadata

The Tethys Knowledge Base page allows users to view, filter, and further explore all the existing Annex IV sites and associated documents. The Tethys map shows Annex IV activities from around the world and allows you to view information about International MHK development activities and research studies, as obtained from the Annex IV survey forms. Note that the Tethys Map and Knowledge Base contain both Tethys and Annex IV data. If you would like to ONLY view Annex IV entries, please click on Annex IV in the Collection facet box on the right had side of the screen.


Contributing to the Annex IV Effort

This collection of international metadata requires collaboration with technology developers, utilities, project developers, researchers, and others. To notify us of any international ongoing research studies:


Please download an Annex IV Research Study Metadata Form, fill it in, save it and email it back to us.

Note: Returning this form implies your willingness to have the work posted on Tethys.


To notify us of any international project sites:


Please download an Annex IV Project Site Metadata Form, fill it in, save it and email it back to us.

Note: Returning this form implies your willingness to have the work posted on Tethys.


List of OES Annexes

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