PNNL

Abstract

Industry-specific tools for analyzing and optimizing the design of wave energy converters (WECs) and associated power systems are essential to advancing marine renewable energy. This study aims to quantify the influence of phase information on the device power output of a virtual WEC array. We run the phase-resolving wave model FUNWAVE-TVD to generate directional waves at the PacWave South site offshore from Newport, Oregon, where future WECs are expected to be installed for testing. Two broad cases are presented corresponding to mean wave climates during warm months (March–August) and cold months (September–February). FUNWAVE-TVD time-series of sea surface elevation are then used in WEC-Sim, a time-domain numerical model, to simulate the hydrodynamic response and estimate the power output of each device in the array. For comparison, WEC-Sim is additionally run with wave energy spectra calculated from the FUNWAVE-TVD simulations, which do not retain phase information, and with wave spectra computed using the phase-averaged model SWAN. The use of spectral data in WEC-Sim requires a conversion from frequency to time domain by means of random superposition of wave components, which are not necessarily consistent because of to the linear assumption implicit in this method. Thus, power response is characterized from multiple realizations of the wave climates.