Recovery Act - A Variable-Geometry Oscillating Wave Surge Converter Paddle for Maximum Power Output and Survivability

Oscillating Wave Surge Converters (OWSC) have shown great promise as a cost-effective means of harnessing the power of ocean waves, yet very little is known about the effects of different paddle geometries on critical performance factors including energy absorption efficiency, survivability in rough seas, and various environmental impacts. While it is assumed that because OWSC are bottom-mounted devices they are less subject to damage from the destructive forces found at the ocean surface, the precise impact of paddle design on the ability of an OWSC to survive a 100-year storm is unknown. Without this information, we will be deploying devices with unknown operational limits and potentially inadequate protection mechanisms which can create unacceptable risks. In Phase I of this project we will conduct experiments designed to capture baseline data of several paddle geometries starting with the performance of simple shapes in linear wave conditions transitioning to more complex shapes in non-linear wave environments. The Phase I objective is to determine the performance requirements and feasibility of a variable-geometry paddle design that is highly efficient and can respond to a wide range of wave conditions. In Phase II we will develop and test a computational hydrodynamic model and verify its accuracy by conducting tests in controlled environments and in sea trials. At the conclusion of Phase II we will have developed a means of adjusting the shape of an OWSC paddle such that optimal performance within a defined range of site-specific conditions can be achieved. In addition, at the conclusion of Phase II we will have tested and documented a variety of different composite materials and paddle fabrication processes such that commercial OWSC versions can achieve desired performance attributes including, robustness and corrosion and bio-fouling resistance. Commercial Applications and Other Benefits: If Phase II goals are achieved, public benefits will include: a) the establishment of performance, integrity and safety values for OWSC paddles across normal, severe and extreme operating conditions; and b) materials quality benchmarks against which further improvements can be made; leading to; c) more-rapid commercialization of a technology that can reduce U.S. dependence on foreign energy resources, speed compliance with renewable electricity standards (RPS), and reduce risks associated with continued global warming.