Tuesday 21 July 2009

Desertec: African solar power for Europe

www.upi.com
July 17, 2009

BERLIN, July 17 (UPI) - - If it makes it beyond the drawing broad, Desertec Foundation would be the world's largest, most ambitious and expensive green energy project ever: a series of solar thermal power plants across the Sahara desert connecting Africa under the Mediterranean Sea to Europe's power grid.

Desertec Foundation - - with an estimated investment cost of some 400 billion euros, should be capable, by some estimates, of supplying up to 20% of European needs by the middle of the 21st century. While it has the backing of some of Germany's largest high-tech companies and energy utilities, some of Europe's keenest backers of green energy regard it as an ill-conceived pipe dream.

Twelve major European companies have signed a declaration of intent to form a consortium by this fall to be set up in Munich under the name Desertec Foundation Investment Initiative. Within three years the consortium hopes to draw up a project design and master plan for its realization. The companies involved are insurance giant Munchener Ruck, Siemens, Deutsche Bank, German utilities RWE and E.ON, MAN Solar Millennium, HSH Nordbank, ABB, Abengoa Solar, Algerian industrial and food group Cevital, plant construction group MW Zander and international solar specialists Schott Solar.

Siemens Chief Executive Officer Peter Loescher says the project is no more far-fetched than the trans-Atlantic telegraphic cable laid by Siemens in 1876. The technology for solar thermal plants is well established, with plants already feeding power into the grid in California and in southern Spain.

Unlike solar panels, which produce a maximum heat output of 200 centigrade, a solar thermal power plant typically uses hundreds of mirrors to concentrate sunlight for boiling some type of liquid for producing steam via a heat exchanger to drive turbines that generate electricity. One big advantage, say its backers, is that solar thermal heat can be stored at night or when the sun is not shining to continue producing power 24/7.

One strong critic is Hermann Scheer, an acknowledged expert on renewable energy and a member of Parliament for the Social Democrats. With no details yet published about which countries in North Africa might be involved, Scheer describes the project as a "fata morgana" - - a desert mirage - - which is politically as well as economically untested. He believes the costs are incalculable and likely to soar ahead of any projections.

The Desertec Foundation consortium explicitly acknowledge that local communities in the countries where solar energy plants would have to be - - in either electricity or in money - - for the right of construction. Neither the German government nor the EU is willing to fund the project beyond some small amounts of seed money. Scheer points out that the desert is a harsh environment for energy plants and it is unclear where the large amounts of water needed for such plants would come from.

There are also objections that the transmission of power across long distances would lead to huge energy losses, though backers of the idea say transmission via High voltage Direct Current cables would maximize transmission efficiency.

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