Among the possible renewables, is one of the most promising but least valued: transform the motorcycle wavy in electric energy. Around the world there are multiple experiments. And one of these is located in Italy, to be precise a Pantelleria: the first device placed on the seabed 800 meters from the coast was tested and went beyond the study phase, transforming wave motion into energy which was then transported to the shore with a submarine cable to connect with the Sicilian island's grid. The device was developed by Eni in collaboration with the Turin Polytechnicoe from the spin-off of the same university Wave for Energy.
Two years ago Eni launched the project centered on the ISWEC (Inertial Sea Wave Energy Converter) device. After the first studies off the coast of Ravenna, the technicians of the energy company then chose Pantelleria, where the "converter" in this first phase will be able to reach 260 kilowatts of peak electricity production from wave motion. ISWEC technology, which is part of the piano di decarbonization of Eni, has been cited by the European Commission in its strategy for offshore renewable energies as a key example of a wave energy converter.
The submarine hull that transforms wave motion into electricity
ISWEC is a device highly technological designed to supply energy to offshore infrastructure, smaller off-grid islands – for islands far from the mainland that do not have submarine cables to connect them to the mainland – and coastal communities which in this way could save on bills or reduce polluting emissions. Iswec's design is able to adapt to the typical weather and sea conditions of the installation site, through a genetic algorithm that exploits the high computing power available at the Eni Green Data Center (GDC) in Ferrera Erbognone.
The machine consists of one steel hull, 8x15m in size which houses the energy conversion system, consisting of two gyroscopic units of more than 2 meters in diameter each. The device is kept in position, at a depth of 35 metres, by a special self-aligning mooring based on the weather and sea conditions, made up of three mooring lines and a swivel (rotating joint) while the electricity produced is carried landed by an underwater power cable.
Wave motion to produce energy: the advantages
Wave energy has great and numerous potential advantages. Suffice it to say that 70% of the earth's surface is covered by water (of which 97% consists of sea and oceans). In particular, the power that can be developed by sea waves corresponds to around 2 terawatts globally, corresponding to around 18 terawatt hours per year, almost equal to the planet's annual electricity demand. Also, the energy of the sea waves is more predictable, teacher and higher density energy compared to that of the sun and the wind, being available both during the day and at night. A further advantage is the considerable reduction of the landscape impact as the device emerges only for about 1 meter above the water level. Furthermore, ISWEC can be perfectly integrated with other renewable energy production solutions in the offshore sector, such as wind power, in terms of both valorisation of the connection systems to the electricity grid and integration within an area of sea, maximizing the conversion of available energy.
