- [The main report can be found in the full conference proceedings. The files here are the conference presentation and an appendix to the main report,] The specific intent of this presentation is to provide a framework to stimulate thought and discussion about the issue of the potential ecological effects of marine renewable energy development, and in particular, to identify knowledge or data gaps that may constrain our ability to move ahead. The complicated relationship between newly introduced technologies and the function of marine ecosystems is deconstructed using stressor-receptor matrices. The matrices are applied to the project phases for wave and wind energy development: siting and construction, operations and maintenance, and decommissioning. There are only few fundamental differences between wind and wave development: 1) wave energy electrical generation is accomplished within the water column; 2) wind development incudes dynamic (i.e., moving) structures only above the water’s surface, and 3) the density of proposed arrays is much higher for wave than for wind development.
There appears to be enough existing information collected for directly applicable or proxy activities that no real information gaps exist about impacts of the siting and construction phase of device deployment. Site-specific gaps exist until specific project sites are proposed, and technology-specific gaps exist largely for wave energy development because the technologies are in a nascent stage of development. Operations and maintenance gaps are generally similar for the wind and wave technologies, and include principally the environmental stressor groups of static device presence; dynamic device presence in the water (for wave energy devices); energy removal (for wave energy devices); noise and vibration; and electromagnetic fields. Uncertainty about effects originates from lack of adequate information about specific stressor signatures, levels and duration of exposure to receptors and sensitivity of specific species, communities, habitats or ecological processes. Gaps in our ability to predict decommissioning effects seem limited to those relating to infrastructure (e.g., anchors, monopiles) that is left in the marine environment. Many of these gaps are potentially related to scaling effects.
Finally, it is important to note that this presentation describes a manuscript that is considered a work in progress. One assignment for the breakout group sessions at this workshop is to improve the existing gap analysis; results of those discussions are included in this conference proceedings.