ANALYSIS OF MARINE CURRENTS AS RENEWABLE SOURCES

The world is going towards the decarbonization of the production of energy, developing new technologies for a better exploitation of the existing sources. It leads to explore the renewable ones, such as solar, thermal, wind and even the ocean; first ones have been developed for years, earning a lot of achievements, but the main drawback is their unpredictability and irregularity. The exploitation of the ocean’s kinetic energy partially resolves these problems since tidal are much more predictable over long time scales because they follow the Moon cycle, being caused by gravitational interactions between the Moon itself, the Sun and the Earth. Furthermore, to harness tidal power it is used the same technology as wind turbines, but with the main advantage of the high-water density compared to the air, which leads to a significant reduction of the blades’ size. The Thesis, after a general introduction about ocean energy, just focus on marine currents, in particular on the state-of-art of technologies that use this source: types of devices and existing machines, operational, maintenance, and economical aspects, with the addition of a model for a tidal current turbine system. Mediterranean Sea case is then analyzed, to understand the real possibilities of exploiting this resource, with a detailed study of Italian coast. In this regard, a reference mapping is outlined, the energy production of a potential site in suitably chosen location (Strait of Messina) is estimated and a generating machine with predetermined characteristics is analyzed. The goal is to describe and apply a procedure for assessing the energy potential of marine currents in order to obtain, based on actual marine-weather data available, a replicable methodology that could contribute to further studies.