Tidal turbines come in a variety of shapes and sizes, including 2 or 3 blades attached to a rotor (similar to a wind turbine) or subsea ‘kites’. Some devices float, others sit on the seabed or in a seawall.
For wave energy converters, different designs cater for different sites and different wave strengths. Among common concepts are: large buoys that absorb the vertical movement of the waves; flaps anchored close to shore, which are pushed backwards and forward; floating hulls inside which air is compressed by wave movement; and floating rafts connected by a hinge.
SWAC and salinity gradient plants are typically buildings located on the shore that house a heat pump system including pipework, membrane, pumps, tanks etc.