The annual solar irradiation on the earth provides more than 8,000 times the world’s energy requirements. Mathematically speaking, about 1 % of the surface area of the Sahara Desert is sufficient in order to meet the world’s electricity requirements with solar thermal power plants. A solar thermal power plant was already constructed close to Cairo at the beginning of the 20th century. Using parabolic mirrors, the power plant captured and concentrated solar energy and used it to heat oil for boiling water. This in turn was used to drive steam turbines and produce electricity.

The PS10 solar tower power plant, which is located near Seville in the Andalusia region of Spain, has been providing about 11 MW of power since 2007, as has the Nevada Solar One 64-MW plant in Nevada in the United States. The Andasol I-III complex, which consists of three 50-MW power plants located in the Spanish province of Granada, went on line two years later. The market was developing very rapidly at this time, but has now slowed down considerably in comparison with a few years ago. Although the German research facilities and companies in the field of solar thermal power generation belong to the world’s best, they are currently in a difficult environment. High investment costs, the associated financial restrictions and political instability, such as in the MENA region (Middle East & North Africa), are just some of the reasons for this. Above all there is considerable competition with photovoltaics, since it is the price development that contributes to competitiveness. This means that it often takes considerable time for power plant projects to be implemented.

On the other hand, a positive trend can also be seen, with new markets about to be tapped. 2.5 GW of solar thermal capacity is currently in operation and about 1.5 GW is currently under construction. The export-oriented key components developed in Germany, such as absorbers, collectors and mirrors, are being installed on a large scale in solar thermal power plants throughout the world. In addition, the news from Ouarzazate in Morocco shows that the expansion of solar thermal power plants is well under way. After all, they have long become standard practice. This Themeninfo brochure examines the basics of solar thermal plants, their technical components and their application potential, and shows examples from practice.