Development of a novel wave tidal energy converter (WATEC) to lower renewable electricity generation costs.

Objective

"WATEC project deals with the design, fabrication, ""on-field"" testing and commercialization of an innovative hydro-turbine able to convert into electricity the kinetic and potential energy of waves and the kinetic energy of tidal streams. The technology works in three ways: 1- it converts the kinetic energy of tidal streams by applying an undershoot waterwheel principle utilising a flow diverter to accelerate and redirect flow under the rotor; 2- this deflector also redirects waves onto the upper platform where an overtopping principle converts wave potential energy as flow drains past the side of the rotor; 3- a similar approach and flow path is used to capture wave kinetic energy. Thanks to the simultaneous exploitation of both potential and kinetic waves and kinetic tidal hydro-energy in a compact plant and to the technology design optimization, WATEC leads to a industry leading LCOE of 71 €/MWh, much lower than the competing solution for low-head hydropower conversion (100÷270 €/kWh ). The HP plant floating structure is semi-submersible utilising a taut mooring principle and anchor cable shock absorbers to minimise wave impact forces. This approach also eliminates the need for: -) voltage limiting ‘wet mate’ inductive couplings; -) expensive subsea interventions for maintenance and defouling; -) expensive subsea construction techniques. The technology has a low environmental impact (no piling for the deployment of the deadweight anchors and limited seabed trenching are required), an easy installation, a low visual impact in comparison to industry alternatives (it protrudes 10 meters above water level), a full material recovery during the decommissioning process. By WATEC, low-head hydropower sector will be revolutionized as it will be possible to apply a technology able to make competitive damless HP, thus dramatically enlarging the HP application potentialities. "