the thomsen telegraph

A concentrating solar power (CSP) plant in Spain that uses panels to reflect light on to a central tower to produce electricity. Similar plants are proposed for north Africa. Photograph: AP

A tiny rectangle superimposed on the vast expanse of the Sahara captures the seductive appeal of the audacious plan to cut Europe’s carbon emissions by harnessing the fierce power of the desert sun.

Dwarfed by any of the north African nations, it represents an area slightly smaller than Wales but scientists claim it could one day generate enough solar energy to supply all of Europe with clean electricity.

The scientists are calling for the creation of a series of huge solar farms – producing electricity either through photovoltaic cells, or by concentrating the sun’s heat to boil water and drive turbines – as part of a plan to share Europe’s renewable energy resources across the continent.

A new supergrid, transmitting electricity along high voltage direct current cables would allow countries such as the UK and Denmark ultimately to export wind energy at times of surplus supply, as well as import from other green sources such as geothermal power in Iceland.

Energy losses on DC lines are far lower than on the traditional AC ones, which make transmission of energy over long distances uneconomic.

Scientists argue that harnessing the Sahara would be particularly effective because the sunlight in this area is more intense: solar photovoltaic (PV) panels in northern Africa could generate up to three times the electricity compared with similar panels in northern Europe.

Backstory

High voltage direct current (HVDC) transmission lines are seen as the most efficient way to move electricity over long distances without incurring the losses experienced in alternating current (AC) power lines. HVDC cables can carry more power for the same thickness of cable compared with AC lines but are only suited to long distance transmission as they require expensive devices to convert the electricity, usually generated as AC, into DC. Modern HVDC cables can keep energy losses down to around 3% per 1,000km. HVDC can also be used to transfer electricity between different countries that might use AC at differing frequencies. HVDC cables can also be used to synchronise AC produced by renewable energy sources.

Source: The Guardian

EC Company Solar Panels Originally uploaded by necaibew48

Wind and solar power grew at a blistering pace in recent years, and that growth seemed likely to accelerate, especially in the United States under the green-minded administration of the new president, Barack Obama.

But because of the credit crisis and the broader economic downturn, the opposite is happening: Except in isolated markets, like China, installation of wind and solar power is slowing, and in some cases plummeting.

Factories building parts for these industries in the United States have announced a wave of layoffs in recent weeks, and trade groups are projecting 30 percent to 50 percent declines this year in the installation of new equipment, a decrease that bars more help from the government.

Prices for turbines and solar panels, which soared when the boom began a few years ago, are falling. Communities that were patting themselves on the back just last year for attracting a wind or solar plant are now coping with cutbacks.

”I thought if there was any industry that was bulletproof, it was that industry,” said Rich Mattern, the mayor of West Fargo, North Dakota, where DMI Industries of Fargo operated a plant that makes towers for wind turbines. Even though the flat Dakotas are among the best places in the world for wind farms, DMI recently announced a cut of about 20 percent of its work force because of falling sales.

Much of the problem stems from the credit crisis that has left Wall Street banks reeling. Once, as many as 18 big banks and financial institutions were willing to help finance installation of wind turbines and solar arrays, taking advantage of generous government tax incentives. But with the banks in so much trouble, that number has dropped to four, according to Keith Martin, a tax and project finance specialist with the law firm Chadbourne & Parke.

Wind and solar developers have been left hunting for capital.

”It’s absolutely frozen,” said Craig Mataczynski, president of Renewable Energy Systems Americas, a wind developer. He projected his company would build just under half as much this year as it did last year.

The effects of the banking crisis were also being felt in Europe, although industry groups said it was too soon to tell what effect the credit freeze would have on the fast-growing sector.

”There are examples of smaller developers and independent power producers, relying on banking finance, that are affected by the general reluctance of banks to provide liquidity,” Christian Kjaer, chief executive of the European Wind Energy Association, wrote in an e-mail message. ”This may postpone some of these projects.”

He added that big utilities, which have large cash reserves to tide them over during the crisis, could emerge with more projects. ”We may see some of the smaller projects, which have turbine delivery contracts but are struck by the banking liquidity freeze, being taken over by the larger power companies,” he said.

Solar experts also report that demand in Europe has softened, a combination of a seasonal slowdown for winter and a recent cap on solar installations in Spain.

”A large amount of product, much of it Chinese, remains unsold,” and prices are dropping, Ray Noble, a photovoltaic specialist with the Britain-based Renewable Energy Association, wrote in an e-mail message.

China, a fast-growing wind market, has so far shown no signs of a slowdown, according to Steve Sawyer, secretary general of the Global Wind Energy Council.

”The government stimulus package targeted investment in grid infrastructure, which is an important part of maintaining the rapid growth of the Chinese industry,” he wrote in an e-mail message. ”We are expecting another year of rapid growth in the Chinese wind market in 2009. In India, the picture is more complex, and varies state by state. It is too early to tell with the minor markets in Asia yet.”

Source: ENN