Solar concentrators

Reisfeld R, Jorgensen CK (1982) Luminescent Solar Concentrators for Energy Conversion. 49 1-36... 

The state-of-the-art solar concentrators can provide solar flux concentrations in the following ranges, depending on the type of the concentrator [26] ... 

Solar concentrators contract the solar radiation from a relatively large area onto a small area. A parabolic mirror of four feet in diameter covers an area of 4 pi, or 12.57 square feet (1.17 square meters). This surface area is measured on a plane and is slightly less than the surface area of the curved mirror. If the sun is about 20% down from peak strength, its strength should be about 800 watts per square meter. Then the total amount of energy striking the mirror is almost 1,000 watts. 

A proof of concept satellite could use the station s solar panels. These solar panels are 14% efficient, but advances with solar cells and solar concentrators allow panels that are up to 50% efficient. 

Zinc oxide in solid or fine particle form is kept in a reactor cavity that is subjected to irradiation from solar concentrators [92], The dissociation products are zinc (vapor) and oxygen for this first reaction AG=0 at about 2235K [91], The reactor is made of materials like inconel steel, zirconia, silicon carbide or graphite [68,89,92], The graphite is used in special designs to avoid direct contact with chemical species [68], The dissociation products are then cooled rapidly to separate zinc and oxygen, transporting the... 

Figure 17.22 A concept of plant growth chamber covered with surface regolith for radiation shielding. Light could be collected with solar concentrators and piped into the plant chamber (source Sadler and Giacomelli, 2002).

Polymers are used as solar concentrators, support of reaction catalysts, and electrodes for organic batteries. 

Ultra-high temp (1000-3000 C) using solar concentrator... 

Thermal solar collectors are also available in so-called central concentrator or solar concentrator designs. In these configurations, a large number of independently movable flat mirrors (heliostats) are used to reflect the solar radiation onto a central receiver on the top of a tower. Each heliostat moves about two axes. The receiver typically is a vertical bundle of tubes in which the heat-transfer fluid (water or oil or molten salt) is heated by the reflected and concentrated insolation. The molten salt technology also provides thermal energy storage. 

A Swiss-designed artificial island is planned near the equator (Figure 1.41) in the Gulf state of Ras Al-Khaimah. A 100-m diameter prototype is under construction. It is one tenth of the size of the planned solar island. The solar concentrators will convert circulating water into steam, which will produce both electricity and H2. The electricity will be used for plant operation, and the H2 will be sold as fuel. The designers feel that the plant will be cost competitive... 

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