This work investigates wave reflection and loading on a generalised Oscillating Water Column (OWC) wave energy converter by means of large scale (approximately 1:5-1:9) experiments in the Grosse Wellenkanal (GWK), in which variation of both still water depth and orifice (PTO) dimension are investigated under random waves. The model set-up, calibration methodology, reflection analyses and loadings acting on the OWC are reported.On the basis of wave reflection analysis, the optimum orifice is defined as that restriction which causes the smallest reflection coefficient and thus the greatest wave energy extraction. Pressures on the front wall, rear wall and chamber ceiling are measured. Maximum pressures on the vertical walls, and resulting integrated forces, are compared with available formulations for impulsive loading prediction, which showed significant underestimation for The present study demonstrates that a OWC structure can serve as a wave absorber for reducing wave reflection. Thus it can be integrated in vertical wall breakwaters, in place of other perforated low reflection alternatives. The possibility to convert air kinetic into electric energy, by means of a turbine, may give an additional benefit. Thus the installation of such kind of energy converters becomes interesting also in low energy seas.

A feasibility study for installing Wave Energy Converters (WECs) in a Mediterranean port is presented here. The final aim is to evaluate the possibility of building a green touristic infrastructure in a site having ordinary wave energy. In particular, the site of interest is Giardini Naxos, which is located in the northern Ionian coast of the island of Sicily (Italy). A preliminary estimation of the available energy has been carried out. The chosen type of WEC device is the Oscillating Water Column (OWC) system, which is found here to allow for good integration with the vertical breakwater needed for the extension of the existing port. Its feasibility is evaluated from the structural and economic point of view. Towards this aim, the system is tested in the laboratory for estimating the reflection coefficients and the pressures on the structure, which allow us to carry out the optimization of the OWC breakwater. Furthermore, the air turbine noise is estimated and an attenuation chamber is designed to reduce such noise to within acceptable levels. The economic feasibility study allows for an evaluation of the recuperation period of the investment, which is slightly less than the service life of the WEC device.

Physical modelling is extensively applied in the study of Oscillating Water Column (OWC) devices since it furnishes a reliable evaluation of nonlinear effects, as those induced by the interaction between surface waves and air inside the pneumatic chamber. In this paper, a small scale generalized device

This paper presents the feasibility study for a green touristic infrastructure by the installation of a WEC system in the port of Giardini Naxos, in the Mediterranean Sea. The area is characterized by a low amount of annual wave energy. The WEC system chosen is the OWC and its geometry has been tested by means of a small scale physical model. The surface elevation and the pressure on the structure have been recorder in such tests in order to evaluate, respectively, loadings and reflection at the front wall. The eigenperiod of the water column inside the device is also obtained. Finally, the economic return is estimated.

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