Mocean Energy, one of the alternate teams to 9 Wave Energy Prize challenge finalists, is moving forward with the design of their 1:20 scale wave energy converter (WEC).
The Mocean WEC is a hinged raft which works as wave forcing and the bodies’ dynamic responses lead to a motion about the hinge, called flex, which drives a power take-off mechanism that converts the kinetic energy into electricity.
The device has seven degrees of freedom, with the design innovation of Mocean WEC being in the shapes of the bodies, which improves its dynamics and thus power absorption, the company states.
The configurations are based around varying the ratio and position of the water-plane area to the submerged volume, where the water-plane area affects the hydrostatic restoring force and the volume affects the mass and added mass.
By changing these values one can induce coupling between the modes and tune the resonant response to improve performance in wavelengths that are significantly longer than the overall length of the machine.
Consequently, although the power take-off is solely in flex around the hinge, there is extensive cross-coupling with other degrees of freedom, Mocean Energy states.
When it is excited by wave action, the device responds not only in flex, but substantially in heave and also pitch and surge. This results in greater cancellation of the incoming wave and a broader bandwidth response than a standard hinged raft, according to Mocean Energy.
This means that if two teams drop out or are eliminated following the next stage gate review, Mocean Energy will have a chance to compete in the finals.
To remind, Mocean Energy, together with the University of Edinburgh, has also been backed by Wave Energy Scotland with approximately £300,000 for the development of its WEC.
Take a look at the video showing Mocean WEC model testing at Stevens University as part of the US DoE Wave Energy Prize.