For over ten years WaveSurfer projects underwent an extensive environmental assessment with the assistance from The Marine Hydrophysical Institute of the Academy of Sciences of Ukraine. The study featured evaluation of potential impacts on: the seabed, fish and benthic organisms, mammals, vegetation, and water quality. The project study resulted in a finding of no significant impact (FONSI), which is the highest such environmental rating.
The project team considered the following environmental issues:
- Withdrawal of wave energy
- Interactions with marine life and seabirds
- Atmospheric and oceanic emissions
- Visual impact
- Conflicts with other uses of sea space
- Installation and decommissioning
Withdrawal of Wave Energy
WaveSurfer power plants do not present an impervious barrier to waves traveling shoreward. Gaps between units and less than 100% absorption efficiency allow considerable wave energy to pass through the plant. Lowering of wave energy levels reaching the coast may reduce erosion in the site's wave shadow.
WaveSurfer power plants operate in waterS deeper than 25 meters (80 feet) in areas where there are no breaking waves.
Interactions with Marine Life and Seabirds
9 years of operations in different parts of the World show WaveSurfer power plants attract marine life and seabirds. The unit's floating device provide hauling-out space for marine pinnipeds and colonization space for seabirds. As marine pinnipeds and seabird populations become adapted to this artificial space, care must be taken in the decommissioning schedule to mitigate potential impacts to these populations. Submerged components such as anchors and cables may provide substrates for colonization by benthic organisms such as corals creating “artificial reefs.”
There is an expected level of disturbance to the seabed and benthos during installation, but this impact can be minimized by careful site selection and advanced installation techniques.
Atmospheric and Oceanic Emissions
WaveSurfer devices do not use hydraulics, therefore no working fluid spills or leakage are of any concern. No oils, lubricants or any other potentially harmful chemicals are used in WaveSurfer devices.
- Noise: localized, intermittent and short duration noise during installation.
- Electromagnetic Emission (EE): minor and temporary impact from EE on marine organisms in the vicinity of the submarine hub, transformer and cables.
- Electrical Leakage: Mild and temporary discomfort for marine organisms and divers could occur in the unlikely event of submarine cable damage.
WaveSurfer devices due to their low-freeboard design are not visually intrusive on the seascape as viewed from the shore, even from elevated shoreline positions. The units are installed at least several hundred yards (meters) from the shore, beyond the reef, where present.
Because of the fishing activity in offshore shelf waters, WaveSurfer floating devices will have to be appropriately marked as a navigation hazard. In addition to lights, highly contrasting day-markers will be required. Day-markers that meet the US Coast Guard requirement of being visible within one nautical mile (1.8 km) at sea are expected to have negligible visual impact when viewed from shore.
Conflicts with Other Users of Sea Space
Although the potential for conflict with other users of sea space exists, it is not an environmental issue and must be addressed early in the siting of offshore wave power plants.
Installation and Decommissioning
Wave power plant installation issues to be addressed include mooring as well as routing and shore crossing of submarine power cables. Decommissioning issues include disposition of fixed structures on the sea floor, gradual removal of floating platforms in stages e.g. if there is evidence of use as haul-out space by pinnipeds or colonization by seabirds.
The conclusions that we have drawn can be summarized in three statements:
- All energy producing technologies, and for that matter, all human endeavors in general, and ocean energy conversion in specific, have the potential to produce environmental impact.
- Given proper care in siting, installation, operation and decommissioning, ocean energy technology is one of the more environmentally benign electricity generation technologies. Most known negative environmental effects can be minimized and in some cases eliminated by diligent attention to the environmental effects.
- WaveSurfer technology has insignificant environmental impact.