Offshore reliability approach for floating renewable energy devices

Abstract

The viability and success of Marine Renewable Energy installations is strongly dependent on the reliability of devices as this determines the amount of generated electricity and the cost for operation and maintenance. Reliability testing of critical components could mitigate these difficulties and provide device developers with a possibility to reveal early failures, gain information on lifetime criteria and provide project developers, investors and certification agencies with the required reliability demonstration and evidence of suitable risk control. The application of component reliability testing can reveal design weaknesses prior to deployment and establish necessary reliability and maintenance information. Components tested under service simulated conditions could be evaluated regarding performance, expected lifetime and subsequently be (cost-)optimised. Two test facilities that enable component reliability testing for marine renewable energy converters developed within the Peninsula Research Institute for Marine Renewable Energy (PRIMaRE) group at the University of Exeter are described. Those two facilities will allow measuring loads that are experienced in the field through prototype testing at the South Western Mooring Test Facility (SWMTF) and subsequently replicate those load conditions (or information from device developers) at the DMaC for accelerated reliability testing and design enhancement. The (SWMTF) is a unique mooring load and response test facility, at large scale in real sea condition and has been recently installed. The Dynamic Marine Component Test facility (DMaC) is capable to perform accelerated component testing under simulated in-service field conditions in four degree of freedom. This paper will describe the test facilities developed within the PRIMaRE group and discuss the approach of the group to mitigate risk for marine renewable energy installations. Furthermore load and response data from sea trial will be used to highlight the importance of this research activity.