CAPTOW: Control and Power Take-off Optimisation for the WRAM

Project Description

CAPTOW brings together first class expertise and facilities in three European countries in a joint effort to advance an innovative wave energy conversion technology combined with a new and efficient twin rotor air turbine. This combination appears to have excellent prospects of commercial viability. The WRAM ('wave-ram') is an Irish invention, specifically designed for deployment in utility-scale arrays in offshore, deep water, and highly energetic sites. It is based on over 20 years' intense R&D in self-reacting heaving buoy point absorbers. It is a powerful, single-bodied device on compliant moorings with at least two separate air turbine / generator power trains. Unlike other point absorbers, the WRAM is an oscillating system with up to four resonant frequencies, a significant advantage in the changing weather patterns of the North Atlantic. The new twin-rotor air turbine, pioneered in Portugal, follows a steady series of improvements in turbine efficiency, building on experience gained since the initiation of the Pico wave energy converter in 1992. Laboratory tests have confirmed the theoretical predictions, it is exceptionally efficient. This OCEANERA-NET project has three basic strands, - numerical modelling and computer simulation (TCD Dublin and Cruz-Atcheson in Lisbon), true-scale model testing in the IH Cantabria wave tank , and developing the power train with real-sea trials in the Mutriku breakwater. The project will include important developments in powerful simulation tools, and their evaluation against empirical results from the physical tests. The WRAM is now at Technology Readiness Level (TRL) 4 and this project aims to bring the power take-off (PTO) and control systems to TRL 5, validation of main components in a relevant environment. Along with parallel R&D on loads and structures, this project will provide a solid base from which to start the engineering design of a working prototype for deployment on a test site, i.e. TRL 6, technology demonstrated in relevant environment.