Effects of projected wave climate changes on the sizing and performance of OWCs: a focus on the Atlantic North African and European coastal waters

Accurate estimates of the annual energy production achievable by a given wave energy converter are essential for a robust assessment of the associated levelized cost of energy, a key factor in investment decision-making. Inaccurate productivity estimates can arise - among other factors - from uncertainties in evaluating the available wave energy resource. The Climate Data Store of the Copernicus Climate Change Service delivers projections of the wave climate along the 20 m bathymetric contours of the whole European coastlines, covering the period 2040-2100, under two Representative Concentration Pathway scenarios(RCP4.5 and RCP8.5). This work addresses the effect of such long-term wave climate changes on the optimal sizing and performances of an Oscillating Water Column wave energy converter intended for installation along the North African and European Atlantic coastline. The capture width ratio of the device under different wave conditions is computed using an empirical model capable of predicting the device performance with acceptable accuracy and limited computational time. The results show that the optimal geometry of the OWC varies significantly in the different geographical locations and that the long-term changes in the wave energy resource could cause a slight modification of the optimal geometry in each potential installation site.