Environmental Effects of Marine Renewable Energy: Final State of Science Posted

Submitted by Nikki Sather on Apr 25, 2016

The 2016 final report on environmental effects of marine renewable energy (MRE) around the world has been released by the Annex IV initiative. The 2016 State of the Science report was developed under the auspices of the 13 nations collaborating on Annex IV, an initiative under the Ocean Energy Systems.  Led by the US, the 13 Annex IV nations came together to assess the potential environmental effects of MRE development, collaboratively identify ways to address potential effects that hamper siting and consenting/permitting of devices, and facilitate the establishment of the MRE industry.

The extensive 200+ page report was released April 25th 2016, is available for download at http://tethys.pnnl.gov/publications/state-of-the-science-2016. An eight page executive summary of the report can be found at the same site. The executive summary has been translated into six additional languages: Swedish, Norwegian, Chinese, Japanese, Portuguese, and Spanish; these translations are also available on the site.

Topics addressed in the State of the Science report include:

  • Collision risk for animals around tidal turbines
  • Risk to marine animals from underwater sound
  • Changes in physical systems: energy removal and changes in flow
  • Effects of EMF on marine animals from electrical cables and MRE devices
  • Changes in benthic habitats and reefing
  • Marine spatial planning
  • Cases Studies that examine siting and permitting/consenting

Two of these topics are summarized here:

Collision Risk

The potential for marine animals to collide with the moving parts of tidal devices continues to be the most challenging issue for consenting/permitting and licensing of tidal develop­ments. Where proposed tidal energy projects overlap with the habitat of protected species there are concerns that collisions could lead to injury and mortality of indi­viduals, and possibly affect the long-term status of the population. Approaches for observing collisions and animal behavior around turbines requires additional development of specialized instruments and techniques. Research to date has focused on single devices; extrapolating to commercial arrays will probably require additional studies. It is possible to predict rates of collision using numerical models, but these models have not been validated and are not particularly accurate. Collisions with tidal turbines have examined collision for individual marine mammals and some groups of fish; however, the results must be scaled to include considerations of risks to populations.

Case Studies

To provide insight into the complexities associated with siting and consenting/permitting MRE projects, four case studies were reviewed: two tidal devices (ORPC TidGen® Power System, installed in the United States; MCT SeaGen technology installed in Northern Ireland); one WEC (WaveRoller, installed in Portugal); and one designated test site (BIMEP, in the Basque Country, Spain). The lack of dedicated policies to streamline development of wave and tidal projects presents some challenges. Nonetheless, existing projects provide opportunities to inform future development activities. Lessons learned from each of the studies highlighted approaches that have led to project success and reduced consenting timelines, including: 1) strong stakeholder outreach and inclusion of community concerns into project planning; 2) integration of robust monitoring plans and adaptive management strategies to optimize monitoring and mitigation measures; 3) involvement of subject matter experts in project planning to provide guidance on monitoring and mitigation; and 4) development of a sound Environmental Impact Assessment and stakeholder communication throughout the process.

The information gathered and analyzed for the 2016 State of the Science report can help inform regulatory and research investigations of potential risks to marine animals and habitats from tidal and wave installations and assist MRE devel­opers in developing approaches to min­imize potential effects on marine animals. Used in conjunc­tion with site-specific knowledge, this information may also simplify and shorten the time to permit (consent) deployment of single and multiple device arrays. This report has brought together and analyzed the publicly available reliable information about environmental interactions with MRE devices. The analysis and conclusions drawn are not meant to take the place of site-specific analyses and studies, or to direct permitting (consenting) actions or siting consid­erations in specific locations.

The Annex IV nations collaborating on this project include: Canada, China, Ireland, Japan, New Zealand, Nigeria, Norway, Portugal, South Africa, Spain, Sweden, the United Kingdom, and the United States.


Annex IV
Marine Renewable Energy