Power Enhancement of Wave Energy Converter Array via Wave Runup in Channel

Abstract

When waves pass through a channel, wave elevation is observed to increase, a phenomenon known as wave runup. Attempts are made to utilize the wave runup along a channel supported on a floating platform to enhance the energy generation from the array of point absorber wave energy converters (PA-WECs). Such floating platforms could be integrated into the floating breakwater, floating pier, or other floating platforms utilized as floating cities for efficient ocean space utilization. The channel is created by modeling two vertical walls supported on a floating platform with wave energy converters deployed in the channel. The performance of the wave farm in terms of energy generation (i.e., power) and interaction factor (i.e., q-factor) are assessed. The paper investigates the effect of channel widths and depths on the power absorption of the arrays. A three-stepped floating platform with varying depths along the channel is then studied to obtain optimal depths along the channel where the highest energy is harvested. Thereafter, three arrays of WECs deployed in a larger three-stepped channel (TSC) floating platform are considered and the effectiveness of such configuration in harvesting energy is assessed. The wave elevation surrounding the wave farm is presented to show the effect the wave runup has on energy generation. The results show that the energy generation of wave energy converters when the arrays are placed in three-stepped channel floating platform could be increased significantly. A q-factor above 1.0 could be achieved for wave period greater than 6 s and the array can generate greater energy for omnidirectional waves.