PNNL

Abstract

Marine renewable energy (MRE) is under development in many coastal nations, adding to the portfolio of low carbon energy sources that power national electricity grids as well as off grid uses in isolated areas and at sea. Progress in establishing the MRE industry, largely wave and tidal energy, has been slowed in part due to uncertainty about environmental risks of these devices including harm to marine animals and habitats, and the associated concerns of regulators and stakeholders. A process for risk retirement has been developed to organize and apply knowledge in a strategic manner that considers whether specific environmental effects are likely to cause harm. The risk retirement process is tested against two key MRE stressors: effects of underwater noise from operational MRE devices on marine animals, and effects of electromagnetic fields from MRE electrical export cables on marine animals. Applying the risk retirement process could decrease the need for costly investigations of each potential effect at every new MRE project site and help move the industry beyond current barriers.