The end of an arm of the railway for six monthsundertaking on this point for the time beingIndustrial production started to accelerateIf 2009 will be a contraction of GDP by 4Internally it is a decision in SeptemberAn activist even asked the drafting of a manifestThey were 130000 Native from free fatherlandThe result is that Enel now produces only 33 of the electricity in ItalyTheir social utility cannot go hand in hand with a bloated stock market liquidity3 billion pounds according to Merrill Lynch"With more than 10 million square metres, the France has the second global marine area, behind the United States," likes to remind Chantal Jouanno, Secretary of State for ecology. A size advantage, a priori, to take advantage of a free energy: that of the sea. "Forty minutes, the Sun sends all the energy which humanity needs during a year, said Jean-Louis Bal, Director of renewable energy to the Ademe (environment and energy control agency)." Yet this solar energy is captured 75 by the surface of the sea, where it turns into wind, hot water, currents... "Unfortunately, the delay of the hexagon in the field of TRA (renewable marine energies) is patent. "Currently, around the world, there are some 80 projects TRA: 30 in Britain, less than 20 in the United States and just 5 in France", noted Alain Clément, Director of the laboratory of mechanics of fluids at the Central School of Nantes, during a seminar that the naval school was organized in Brest last February.
"A chain is to create: If the French State does not train in motion, it will be dominated by the Anglo-Saxons", summarized Michel Paillard, one of the rapporteurs of Ipanema (Initiative national partnership for the emergence of marine energy, signed in October 2008, by a hundred actors, including Alstom, Areva, EDF, Total...).
Risky bet
For some, the battle of the energy of the waves (wave machines) and that current (current turbines) would be already lost (see below). Possibly remain offshore wind turbines and the SEM (thermal energy of the seas) markets. Two niche interest precisely the Group DCNS ex - DCN, Direction of shipyards , military naval engineering specialist, with net sales EUR 2.8 billion in 2007 and 12,700 employees. This newcomer in the EMR market displays big ambitions. "Exports of military naval hardware, energy and services should represent half of our turnover to here in ten years, against 25 today," hope Frédéric Le Lidec, Director of the sea of the DCNS group development.
First small stage of the redeployment to the TRA: DCNS has signed an agreement with the Regional Council of reunion last April to investigate the installation of a demonstrator of the thermal energy of the seas as a platform anchored off the coast of the island. The region and DCNS will invest 655.000 and 400,000 euros.
The bet is for the less risky. With this technology, it operates the differences in temperature between the surface of the Sea (hot) and the (cold) waters in depth. A fluid sea water, ammonia... passes from liquid to vapor State in an evaporator in which circulates hot water drawn on the surface. Steam is relaxed in a turbine which results in a generator, thus producing electricity. Then the steam passes through a condenser where, in contact with cold water pumped in depth, it returns to a liquid state.
One of the handicaps, it is that this does not occur everywhere. Must be a difference of at least 20 degrees, throughout the year, between the water surface and in depth. Only the intertropical zone meets this criterion. A report published last year by Ifremer (French Institute of research for the exploitation of the sea) estimates that the thermal energy of the seas will be a 200 MW of installed power (i.e., roughly one-sixth of the power provided by a civilian nuclear reactor) in 2030 in the DOM - TOM.
Technical challenges
Another concern, the technical challenges are many: corrosion of materials, resistance to frequent hurricanes in the tropics... Despite this, interest in this approach appears to be reborn. The US Government awarded last October 1.2 million dollars (850,000 euros) to Lockheed Martin, more important industrial group of weapons in the world, to develop pipes to the SEM. "Lines are one of the keys to this technology," confirmed Jean Marvaldi, engineer at the Ifremer in Brest, where he is, among other things, Member of the Group of marine renewable energy projects: "A central of several tens of megawatts may require lines of 5 metres in diameter and 900 to 2,000 metres in length." "For the demonstrator of the meeting, we plan to use a rigid pipe composite of 1,000-1,100 metres long, detailed Daniel Bathany, generic SEM project leader in DCNS.". To decouple these rigid pipes of the movements of the float, we course both by flexible pipes. "In General, all technologies chosen for the meeting will be"available on shelves technologies. " A wise way to reduce the "fortunes of sea", as say the sailors...
