Italy has around 8,000 kilometres of coastline. The sea could therefore become, in addition to an economic and tourist resource, an energy source that is renewable and low-impact. By 2020, according to the National Renewable Energy Plan and as reported by Gianmaria Sannino, head of the Enea laboratory for climate modelling and impacts, we will need to install the first 3 MW of electricity produced from wave motion.

The Pewec system, in scale and on display in Rome.

It is for this reason that Enea (the National Agency for New Technologies, Energy and Sustainable Economic Development) has presented a new low-cost system for producing energy from waves. Called Pewec (Pendulum wave energy converter), it was developed in collaboration with the Politecnico di Torino and designed specifically for our coastlines, where waves are mostly small in height and high in frequency.

Once completed, the device will have a rated power of 400 kW and will be capable of producing electricity by harnessing the oscillation of the hull caused by wave motion. Sannino confirms that: "This low-cost system for producing energy from the sea is particularly interesting for Italy's many islands, where the energy supply is guaranteed by costly and polluting diesel power plants." By installing around ten of these devices, the researcher notes, it would be possible to produce electricity for a town of 3,000 inhabitants. Lampedusa has a population of around 6,000.

By developing and installing these devices, we could harness a constant energy source — far more so than wind and sun — that has already been tested in other countries "blessed" by the sea. From the southern hemisphere to the northern. "Italy possesses significant potential energy associated with wave motion, comparable to that found on the eastern coasts of the North Sea. The western coast of Sardinia, for example, has an average annual energy flux value of around 13 kW/metre, while that of north-west Sicily is around 10 kW/metre." Beyond this, the technology can also: "contribute significantly to countering erosion phenomena by reducing the energy of waves breaking on the coast, without significantly impacting marine flora and fauna."

This is precisely what is being done off the coast of Marina di Pisa (the most recent project in chronological order), where on 22 July last a similar system was presented: the Marina di Pisa Wave Energy Park, a technology resting 3 metres above the seabed, approximately 200 metres from the shore, with a capacity of 25 kW. "Marine energy represents a real opportunity to foster economic growth and employment, improve energy supply security and — Sannino concludes — increase competitiveness through technological innovation."