The total useful wave resource around the world is estimated to be larger than 2 TW. Harvesting a small portion of the available wave energy resource could contribute significantly to meet the urgent energy demand. Therefore, a lot of wave energy converters have been developed in the past decades. Traditionally, air turbine, hydroelectric motor and linear electromagnetic motor are used in wave energy converters as the power takeoff system. Although these power takeoffs have their own advantages, power takeoffs are still recognized as the most important challenge in ocean wave energy technology. In this paper, a mechanical motion rectifier (MMR) based power takeoff system is proposed and prototyped for wave energy converter. This power takeoff system can convert the bi-directional wave motion into unidirectional rotation of the generator by integrating two one-way clutches into a rack pinion system. A 500W prototype which contains a heaving buoy and MMR-based power takeoff system was designed and fabricated. The models of power takeoff system and the corresponding single-buoy wave energy converter are built and analyzed. Lab testing of power takeoff mechanism and ocean testing of the overall ocean wave converter system are also conducted.
Mapping and Assessment of the United States Ocean Wave Energy Resource
