Performance improvements of mooring systems for wave energy converters

In the development of wave energy converters, the mooring system is a key component for a safe station-keeping and an important factor in the cost of the wave energy production. Generally, when designing a mooring system for a wave energy converter, two important conditions must be considered: (i) that the mooring system must be strong enough to limit the drifting motions, even in extreme waves, tidal and wind conditions and (ii) it must be compliant enough so that the impact on wave energy production can be minimised. It is frequently found that these two conditions are contradictory. The existing solutions mainly include the use of heavy chains, which create a catenary shaped mooring configuration, allowing limited flexibility within the mooring system, and hence very large forces may still be present on mooring lines and thus on anchors. This solution is normally quite expensive if the costs of the materials and installation are included. This paper presents a new solution to the mooring system for wave energy converters within the FP7 project, ‘GeoWAVE’, which is a project aiming to develop a new generation of the moorings system for minimising the loads on mooring lines and anchors, the impact on the device motions for power conversion, and the footprint if it is applicable, and meanwhile the new types of anchors are also addressed within the project. However this paper will focus on the new mooring system by presenting the wave tank test results of the Pelamis wave energy converter model and the new developed mooring system. It can be seen that the new generation of mooring system can significantly reduce the loads on mooring lines and anchors, and reduce the device excursions as a result of the new mooring system when compare to the conventional catenary mooring.

A philosophy of performance, politics and composition

This thesis discusses socio-political issues worldwide through philosophical approaches to performance, politics and composition. My research also discuss sound decisions which I regard to be simultaneously an outlet for personal expression, as well as a practical tool to inspire a socio-political change in society. Although the latter is paramount to the methodology of the project, the sound cannot be regarded in isolation as a “political composition”. It can only become truly functional in a political sense through interaction with other art forms, within the context of a specific place and time. My portfolio for this project is of two socio-political projects which are my chief concern. The first project concerns the Israeli-Palestinian conflict. I named this project PATH. PATH aims to foster and expand peaceful thought between Jewish and Palestinian civilians in Israel-Palestine. Through performance art, PATH spreads a message of acceptance, unity and brotherhood between our peoples. Above all, PATH demands and end to intolerance, hatred and violence among all the inhabitants of the State of Israel. The second project concerns women’s rights globally. I have realised that although we have come a long way in our struggle for rights for women, great challenges remain. There is a need to unite women and men against a form of oppression that discriminates against 50% of the world’s population. I called this project, For Utopia.