The Subwave system will be manufactured from different polymer plastics (polyeten and polyurethane) and stainless steel. There will be no emissions of any kind to the sea.
We lack experience about how a large-scale developement may affect the marine environment. The biggest concern will perhaps be related to sound effects that could disturb migratory patterns of marine mammals and fish.
Vertical movements of buoys and turbines will be maximum 6 meters per second and the rotational speed will be maximum a little over 100 rpm. Whales, seals, sharks, fish and sea birds will probably have the ability to stay away from the wings as the speed is relatively low and predictable.
On the other hand, both fisheries and other maritime traffic have to keep off. The entire water column and seabed below will thus become a protected sanctuary that can benefit a lot of species.