Report of a group set up to review wavemakers and wavemaking technology in OCRE facilities

This report presents the results of a review of the wavemakers and wavemaking technology at OCRE. The review was carried out between April 2013 and February 2014 by a group of eight people with different responsibilities who shared an interest in waves and wave generation. Issues addressed by the Group included what needed to be done to ensure the wavemakers will continue to operate reliably and to meet the needs of clients in the future. The review considered wavemaking hardware, control systems and software for wave generation and analysis of the results. The need for expertise in the field was also included. Problems or limitations to capabilities in these areas were identified, together with the impact or importance of the problem, options for solutions and pros and cons for each option. The steps required to resolve outstanding issues were documented and where possible the preferred option identified The review led to the following recommendations: Replace the wavemaker in the Towing Tank; Address the rustout issues in the MWB; Replace the actuator rod end bearings in the drive system in the OEB; Replace the hydraulic drives with electric drives and simplify the linkages in the OEB; Bring the control systems for all OCRE wave generation facilities to the same high level; Acquire software for wave generation to include 2nd order waves and active wave absorption; Fit wave probes to each segment in the OEB to enable active wave absorption; Create a new position (or re-assign an existing staff member) to provide direct support to the operation of wavemakers in the facilities.NRC publication: Ye

Supplementary material from "Wave energy absorption by a submerged air bag connected to a rigid float"

A new wave energy device features a submerged ballasted air bag connected at the top to a rigid float. Under wave action, the bag expands and contracts, creating a reciprocating air flow through a turbine between the bag and another volume housed within the float. Laboratory measurements are generally in good agreement with numerical predictions. Both show that the trajectory of possible combinations of pressure and elevation at which the device is in static equilibrium takes the shape of an S. This means that statically the device can have three different draughts, and correspondingly three different bag shapes, for the same pressure. The behaviour in waves depends on where the mean pressure-elevation condition is on the static trajectory. The captured power is highest for a mean condition on the middle section

Database of costs for wave energy projects

The database of costs is a list of costs related to the commercialisation of a wave energy farm. The costs are collected in an Excel sheet divided into categories. This collection of costs is intended to be used in LCoE calculations. The data has been gathered through a thorough literature review

SparBOFWEC Spar Buoy for Offshore Floating Wind Energy Conversion - Data Storage Report

The present work describes the experiences gained from the design methodology and operation of a 3D physical model experiment aimed to investigate the dynamic behaviour of a spar buoy (SB) off-shore floating wind turbine (WT) under different wind and wave conditions. The physical model tests have been performed at Danish Hydraulic Institute (DHI) off-shore wave basin within the European Union-Hydralab+ Initiative, in April 2019. The floating WT model has been subjected to a combination of regular and irregular wave attacks and wind loads