Understanding potential environmental impacts is a key issue in gaining acceptance of new technologies. Primary concerns relating to tidal stream turbine installations are interference with the local ecosystem during installation activities, the potential of the rotating blades to injure fish, diving birds and sea mammals and the loss of amenity, fishing areas and navigation space for other users of the sea area.
As Evopod™ is a floating tethered device it imposes less disturbance on sensitive seabed ecosystems that bottom mounted structures and its unducted turbines coupled to a geared drive rotate at such low tip speeds that they are unlikely to be a threat to marine wild life. Nevertheless Oceanflow’s Sanda Sound project embodies an extensive pre and post installation environmental monitoring program in order to better add to the body of environmental impact knowledge and de-risk future projects.
Evopod’s spread mooring solution employs a tight envelope to reduce the size of the exclusion zone for shipping. Single Evopod units pose a navigation risk not dissimilar to vessels passing a tethered navigation buoy. Farms of device would involve creating an exclusion zone where typically a one square kilometre of seabed in an area such as the Pentland Firth could deliver enough energy to support 40,000 homes. This would reduce carbon dioxide emissions by 140,000 tonnes per annum, if replacing power from a coal-fired power station.