Experimental solar power plant

Germany -
  • Insulation of a solar power plant


There is a growing global awareness that sustainable sources of energy are essential. Renewable energy sources are best and for the past 2 years Microtherm has been increasingly active in Concentrated Solar Power (CSP), arguably the most attractive of all available sources because of the unlimited solar energy reserves available in the sunny regions of the world.
As soon as the sun begins to shine, the tower mirrors – also called heliostats – align themselves so that the sunlight reflects onto the tower. This concentrated sunlight is directed to a receiver in the top of the tower. The receiver consists of many individual absorbers made out of a special ceramic, which are heated by the sunlight. Air is sucked into the tower from outside and heated, along with air from the inner circuit, to 700°C by the absorbers. The hot air is used to produce steam, which drives a turbine. Finally, a generator converts the rotational energy from the turbine into electricity, which is then fed into the public mains supply. It is also
possible to direct the heated air into a thermal collector.

This thermal collector consists of an insulated steel housing filled with ceramic chequer bricks. If the sun is not shining, heat can be
taken from the collector to produce steam, and thus electricity. In this way, controlled electricity can be supplied at any time. All functional components, such as the boiler, hot and cool air pipes, receiver, thermal collector, steam turbine and generator, are stored centrally in the tower.

Promat High Temperature Insulation was responsible for supplying and installing the inner lining of the housing for the thermal collector, the hot air pipes and the construction of the radiation shield.

The housing of the thermal collector was constructed modularly from over 24 individual components at a steel plant. The thermal principle and the structure of the wall of the inner lining are similar to those of a common thermal reactor; the temperature is approximately 750°C.

Because of the tight spaces in the tower, separate steel containers could not be used. Heat-resistant plates had to be used to make separate individual chambers. For this purpose, SUPALUX®-V was used. The plates were bolted together with standard Spax screws in staggered levels. Whilst construction was taking place, the ceramic chequer bricks were concurrently inserted. It was not urgently necessary for the chambers to be gas-tight in order to use the thermal collector, as would usually be the case.

PROMALAN® was installed in the bottom of the lower inflow chamber and ceramic ALSIFLEX® fibres were installed on the walls. Due to high wind speeds, a PROMAFLEX® towel was placed on the front side of the chamber and secured with pins and clips. The walls constructed around the supporting grid and the cupola were lined using the PROMACOMB® lightweight construction system.