Wave energy potential in the north-west of Sardinia (Italy)

Abstract

Abstract Sardinia (Italy) is the second largest island in the Mediterranean Sea and its economy is penalized by high costs of electricity, which is double compared to the continental Italian regions, and triple compared to the EU average. In this research, the wave energy potential of the north-west of Sardinia has been studied by an analysis of wave measurements carried out in a 20-year period by the Italian Wave Buoys Network (1989–2009) and the corresponding hindcast data by the European Centre for Medium-Range Weather Forecasts (ECMWF). The annual offshore wave power was found to range between 8.91 kW/m and 10.29 kW/m, the bulk of which is provided by north-westerly waves. The nearshore energetic patterns have been studied by means of a numerical coastal propagation model (Mike21 NSW). The analyses highlight two “hot spots” where the wave power is respectively 9.95 and 10.91 kW/m. For these locations, a Wave Energy Converter with maximum efficiency in the ranges of significant wave heights between 3.5 and 4.5 m (energy periods 9.5–11 s) and 4–6 m (energy periods 9.5–11.5 s) respectively should be selected. In order to find a concrete solution to the problem of harvesting wave energy in this area, the characterization of waves providing energy is considered along with additional considerations, such as installation and operational costs, institutional factors, environmental sensitivity and interferences with others human activities. On the basis of the information available and the identified circumstances, the site of Bosa Marina has been proposed as a prospective wave farm location. For this site in particular, multifunctional structures like harbour or coastal protection breakwaters equipped with a WEC are recommended.