Desertec Dreams Can Saharan Solar Power Save Europe?

Is it a mirage? Some experts think so, others say it will become a reality.
AP

Is it a mirage? Some experts think so, others say it will become a reality.

Part 4: Can We Make Solar Power Cheaper?


One kilowatt hour of solar thermal energy costs about 20 euro cents and is therefore still more expensive than an hour of conventional power, which costs around six cents. But according to some experts, if a solar power plant is built in a sun-rich area, then the prices could fall to 18 or even 14 cents an hour.

Many experts believe prices will fall, including Nikolaus Benz from Schott Solar CSP. "By the year 2020, a kilowatt hour of solar energy will cost less than 10 cents," he predicts. If you add to that climbing oil prices, as well as the costs of CO2 emissions, solar power starts to look more and more competitive.

The first solar thermal power plants were built in the 1980s in the Mojave Desert, and they are still going. "And we are expecting operating lives of around 40 years," Benz says. "It is astounding that we can reach these kinds of values already with the first generation."

Coal power plants have been around for over 150 years and, when they started, their efficiency was around 5 percent. Which means solar thermal power has more than a few chances to become equally, if not more, efficient.

So what does a solar thermal power plant cost? "A 250-megawatt parabolic dish power pant with a salt storage facility can be built for €1 billion ($1.5 billion)," Benz says. Coal-fired power plants or nuclear plants, which have 45 and 35 percent efficiency respectively, are therefore less expensive. It is possible to build a coal-fired power plant that performs almost four times better for around €1.2 billion. However the latter requires a constant supply of fuel, which obviously incurs costs. Sunlight, on the other hand, is free.

Additionally, in the six cents that it costs to produce that one kilowatt hour of conventional energy, there are a variety of factors unaccounted for. Coal and uranium must be produced, which costs money as well as damaging the environment and creating more CO2 emissions. In addition, spent fuel rods need to be disposed of, and CO2 emissions must be dealt with.

From 2013 onwards, coal-fired power plants will have to pay for every ton of CO2 that they produce. And the underground CO2 storage that is currently being researched will also reduce the efficiency of coal-fired power plants by around 10 percent. On the other hand, a solar thermal power plant runs without emissions, has made back the energy that it took to build it within a few months of operation and will have recouped its construction costs within 20 years, Schnatbaum-Laumann enthuses.

Werner Platzer, a senior scientist at Europe's largest solar energy institute, the Fraunhofer Institute for Solar Energy Systems, points out that there are other critical points that will determine the price of solar energy. These include the fact that parabolic dishes have yet to be mass-produced -- when they are, they will be cheaper -- and the fact that only small solar thermal power plants have been built so far. It stands to reason that the bigger the plant, the cheaper the power coming out of it. Platzer also notes that the more plants that are built, the more experience we will have with solar power and the cheaper (and faster) future planning processes can be. Additionally, the technology going into solar power will only improve.

Article...

© SPIEGEL ONLINE 2009
All Rights Reserved
Reproduction only allowed with permission


TOP
Die Homepage wurde aktualisiert. Jetzt aufrufen.
Hinweis nicht mehr anzeigen.