Conference article

This paper presents a developing concept of a low cost “point absorber” Wave Energy Converter (WEC). The WEC is unique in that instead of operating with one buoy; two are used to optimize the hydrodynamic response and energy output. This makes the design a three-part system: the surface buoy provides the vertical translation and hosts the primary interface for energy absorption; the power take-off (PTO) device which is a direct drive permanent magnet AC generator; and lastly the tension buoy that feeds through the PTO to the surface buoy. The total cost of the 2 KW WEC is less than $2000 USD including the PMAC generator; power converter and cable to charge the batteries for electric vehicles. The integrated dynamics of the WEC and the PTO are presented using a simplified model of a heaving buoy. The wave energy resource of a test location is analyzed and presented based on data from a global Wave Watch III model surrounding Oahu. The characteristics and distributions of the movement patterns of individual vehicles are measured. It was shown that regenerative braking power has the major role in reducing the total energy consumption and decreasing the size of the required battery to be charged externally by the WEC. In addition the power used by vehicle follows the Rayleigh distribution. Thus; the batteries for individual driver are customizable. This significantly reduces the amount of energy required by distributed WEC generators.

Wave energy conversion; point absorber; electric vehicle