Konstruktion und Deutung - Jörg Schlaich, Rudolf Bergermann und Partner, Stuttgart
Aedes presents Jörg Schlaich’s and Rudolf Bergermann’s solar chimney power plant, which already functions as a prototype in Manzanares, Spain. Jörg Schlaich and Rudolf Bergermann are among the best-known contemporary civil engineers and are active worldwide. With this project, they pursue a vision of a world made better by improved energy provision, in particular for poorer countries.
For many developing nations, which outdo the industrial North only in their abundant sunshine and desert sands, the utilization of solar power represents a feasible path toward adequate energy provision. The precondition is a large-scale solar power plant run by high levels of solar radiation. The plant must be simply and dependably constructed, and must run virtually maintenance-free for a period of many years. It cannot produce waste heat, and cannot require coolants. It must be constructed to a large extent from environmentally neutral and renewable raw materials, and moreover by local labor and with resources that are available locally in such materially poor countries. If surplus production going beyond local needs allows the export of solar energy, than the global climate and humanity as a whole benefit.
The solar chimney power plant fulfills all of these conditions: Beneath a large, circular glass roof, air is heated via solar radiation. This in turn streams into a circular chimney pipe at the center of the roof and is then drawn upward. By means of turbines, this updraft is converted into electricity at the foot of the chimney.
In technological terms, then, the solar chimney power plant is very similar to a hydroelectric power plant - the sole truly successful source of renewable energy to date.
The scheme combines three familiar technologies in the new manner:
- The glass roof warm air collector is not restricted to utilizing direct sunlight, but can also exploit diffuse solar radiation under overcast conditions, an advantage for countries with frequent cloud cover.
Water-filled tubes laid out below the glass roof store solar energy during the day, releasing it at night, so that performance remains constant over a 24 hour period. The roof diameter of several kilometers was determined by the anticipated capacity, together with storage in the region of 100 to 400 MW (a contemporary nuclear power plants has an output of 1200 MW). In dusty regions, the roof is cleaned by large vacuum cleaners.
Because nearly one half of the total costs flow into the labor-intensive collector roof, energy from solar chimney power plants is reasonably-priced and economically competitive in low-wage countries.
- The reinforced concrete uptake duct: The taller this duct is, the stronger the updraft, which means higher performance, but higher costs as well. The optimal ratio between the diameter of the glass roof and the height of the duct must be calculated for each specific location. Today, reinforced concrete ducts 1000m in height can be constructed without difficulty. Glass for the roof and cement for the duct are made of sand, that is to say, from an inexhaustible raw material.
Once a single glass and cement factory has been built in the desert, and supplied with energy from an initial solar chimney power plant, then it can "propagate” itself in an environmentally neutral manner. Since a solar chimney power plant requires 2.5 years in order to reproduce itself energetically, a single plant can produce 30 "offspring” over a period of 75 years.
- The wind turbines with generators: At the foot of the duct, a large turbine with a vertical axis and a generator converts the air stream - which travels at circa 45 km/h - into electricity. Alternatively, 24 to 36 turbines with horizontal axes can be arranged in a circular configuration at the transition from roof to duct.
In contrast to conventional thermal power plants, solar chimney power plants require no coolant, and in contrast to wind turbines run on naturally gusty wind (which, given the same diameter and wind stream, have only approximately 1/10 of the output of these sheathed turbines), they run on an airstreams with uniform velocity, which means that they are exposed to less stress and can run indefinitely with minimal maintenance.
A prototype in Manzanares, Spain has been producing energy without problems for seven years, thereby demonstrating the operational reliability and dependability of this novel type of solar power plant. Solar chimney power plants will make it possible for us to take the decisive step toward a global solar energy economy. From the technological point of view, large-scale solar chimney power plants with capacities between 200 and 400 MW are feasible today without difficulty.
The exhibition presents the solar chimney power plant through models and images. Visitors are invited to wander through the desert sands.
The exhibition featuring Jörg Schlaich and Rudolf Bergermann runs parallel to the exhibition devoted to Volkwin Marg, Hamburg.
Speaking at the opening will be
Kristin Feireiss AedesBerlin
Diese Ausstellung wurde ermöglicht mit der großzügigen Unterstützung von:
