REWEC3 wave energy converter is oscillating water columns (OWC) type of device that uses the oscillatory motion of mass of water induced by a wave in a chamber to compress air to drive the air turbine.
Wavenergy.it, an Italian ocean energy developer, has developed REWEC3, a reinforced concrete caisson that can be built in dry docks.
The caisson has, on the wave-beaten side, a vertical duct that is connected both to the sea through an upper opening, and to an inner room through a lower opening.
The inner room contains a water mass in its lower part and an air pocket in its upper part.
An air-duct, which connects the air pocket to the atmosphere, contains a self-rectifying turbine.
When waves produce a pressure fluctuation at the outer opening, water oscillates up and down in the duct, and the air pocket alternately is compressed and expanded. Then, an alternate air flow is obtained in the air duct which drives the self-rectifying turbine.
The water column acts as a piston on the air volume, pushing it through the turbine as the waves increase the water level in the chamber, and drawing it as the water level decreases.
A coaxial generator produces electrical energy.
The estimated REWEC3’s average electricity production during 1 year period from a REWEC plant with total lenght of 1 km is 6 – 9 GW/h in the central Mediterranean Sea, 66 GW/h in the California region, and 40 GW/h for the Atlantic EU coast.
Wavenergy.it is currently building the first REWEC3 caisson Civitavecchia, near Rome, Italy.
Take a look at the animated video of REWEC3 wave energy converter in operation.
Source/Image: Wavenergy.it