Monday, 4 July 2011

Renewable Energy from the Mediterranean

The sea provides waves, marine currents and tides, all of which could produce energy. The saline gradient and the thermal gradient of the sea could also be used. These technologies are still at the experimental stage, although some countries like the UK, Norway, the US, Portugal, Canada and Japan are investing in research in them. Italian researchers have achieved a great deal in these fields and are well known internationally.

ENEA, Ente per le Nuove tecnologie, l'Energia e l'Ambiente (National Agency for New Technologies, Energy and the Environment) is the Italian Government sponsored research and development agency, originally set up to research atomic energy. Ever since the referendum 25 years ago, in which an overwhelming majority of Italians voted to shut down all nuclear power stations, ENEA has focussed on renewables. However, when Berlusconi announced a few years ago that he wanted to build a new fleet of nuclear power stations, ENEA funding was once again diverted away from renewables.

But Berlusconi did not get his own way. More than a million signatures were collected, enough for the people to demand a referendum on new nuclear. Despite all Berlusconi’s efforts to block the referendum, 57% of the Italian people voted and 97% of these voted against any form of new nuclear power.

As soon as the results of the referendum were made public, Vincenzo Artale, physicist and oceanographer for ENEA, called all the main Italian experts in the field of marine energy to come to a workshop in Rome, to discuss the prospects for the development of this energy sector.

“There are problems”, he said, “but 20 years ago the problems for wind turbines looked insurmountable”.

“We’re mapping the coast and the Italian seas with a grant of 500,000 euros from the Ministry of Economic Development. It’s not enough. The government should be investing a lot more,” he said. “Using wave and tidal power, countries like Scotland could produce enough energy for all their needs. In fact Scotland is working on under-sea barriers.”

Interviewer: “And in Italy Professor Artale?”

“The Mediterranean doesn’t have the same tidal energy as the north seas but there are optimum areas for exploiting tidal energy (which, unlike wind, is regular and energetically quantifiable. And waves. The Strait of Messina is a good place. There’s already a prototype turbine with vertical blades. It’s called Kobold (Italian technology, similar to wind turbine blades but planted horizontally deep in the sea, a good place to exploit tidal energy.)”

“A wind turbine blade 10 metres diameter produces the same energy as a sea turbine blade one metre diameter. The Strait of Boniface (between Sardinia and Corsica), the area of sea south of Sicily, a good part of the Terrenian sea, (between Italy, Sardinia and Sicily) the Ligurian sea (between Italy, Corsica and France) and the Strait of Gibraltar, where the Spanish government is installing an Italian prototype, are all good places to exploit marine energy.”

“To transform wave energy into electricity on the other hand, there is now a system called REWEC3 (resonant wave energy converter), a caisson breakwater that protects a port and, at the same time, converts wave energy into electrical power. Otherwise floating snakes that use the undulating oscillations of the sea could be used.”

Interviewer: “Where is this research being carried out in Italy?”

Artale “We at ENEA are providing all our know how, just like the CRN researchers, free to anyone who wants to use it. Then there are proactive universities like the ones in Messina, Reggio Calabria and Naples, but the University of Bologna, Milano and Torino are all involved in this research too. They developed the Kobold prototype, but worldwide there are lots of marine energy patents. Indonesia is developing marine energy.”

“But since our nuclear scientists now have time on their hands and marine energy research is in its infancy, we could really intensify our renewable technology research efforts, focussing on integrated forms of production, with platforms that exploit wind, sun and sea together. Meanwhile the European Community is already announcing funding specifically for marine energy.”

Interviewer “What impact do these technologies have on the environment?”

“The sites need to be assessed very carefully, just as they do for wind turbines and solar voltaics. Obviously we can’t start planting deep sea turbines right near to beaches. But as far as wildlife is concerned these types of technology have very low impact, far less than wind turbines. The REWEC3 caisson breakwaters are places where fish collect.

Eleonora Martini. Onde e Maree: Dal Mediterraneo l’energia rinnovabile del futuro.

Il Manifesto 17 June

translated by Angela Paine