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Innovative modular foldable concentrating solar energy system

By Ruby Rogers,2014-12-13 16:23
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Innovative modular foldable concentrating solar energy system I. Detailed description of the drawings Fig. 1. Typical assembly of reflectors of the Cassegrain type The classical optical concentrating system in the art (typical assembly of reflectors of the Cassegrain type), as shown in Fig. 1, comprises concentrating parabolic surface 1 with a focus (focal line, in cas..

    Innovative modular foldable concentrating solar energy system

    I. Detailed description of the drawings

    Fig. 1. Typical assembly of reflectors of the Cassegrain type

    The classical optical concentrating system in the art (typical assembly of reflectors of the Cassegrain type), as shown in Fig. 1, comprises concentrating parabolic surface 1 with a focus (focal

    line, in case of cylindrical surfaces) F coinciding with the focus

    of the collimating parabola 2. The incident parallel light rays of

    size a in Fig. 1 fall upon the reflective surface of the

    concentrating parabola 1 and are concentrated at the focus (focal

    line) F. The concentrating ratio a/b to the outgoing collimated

    light beam can be changed by varying the parameter of the collimating parabola 2. By rotating the collimating parabolic

    reflective surface 2 around the focus (focal line) F, the outgoing

    light beam changes only its path, without changing the concentration of the collimated light rays. Some of the problems of this widely known system are: the first one is the need of cooling the collimating surface 2, which, as a rule, is much

    smaller than the concentrating one 1. It can be resolved by

    applying forced cooling, by thermally

    coupling the collimating 2 to the

    concentrating 1 parabolic surface as

    well as by ensuring additional cooling

    surface. The problem can also be

    resolved by enlarging the area of the

    collimating surface 2 to allow for

    maintaining the heating within

    permissible limits, as is shown in Fig.

    2. The other problem is the

    overshadowing of a portion of the

    concentrating parabolic surface 1 and

    a portion of useful incident light rays

    is lost while the collimated surface 2

    heats additionally. As it is shown in

    the Fig. 3, this problem can also be

    resolved.

    Fig. 2 is an embodiment of Fig. 1, but the

    collimating parabolic surface 2 has the

    area of size a, commensurate to the

    aperture of the concentrating parabolic

    surface 1. In this case, to realize the same

    concentration of incident light rays, as in

    Fig. 1, the parameter of the collimating

    parabola of the surface 2 should be much

    smaller than that in Fig. 1. In this way the

    heating of the collimating parabolic

    surface 2 is practically commensurate to

    that of the concentrating parabolic surface

    1 from Fig. 1. If needed, the area of the

    collimating parabolic surface 2 can be

    enlarged depending on the needed

    dissipated heat power. This construction

    allows such positioning of the collimating

    parabolic surface 2 so that it is located at

a sufficient distance from the caustic point (line) F. In case the collimating parabolic surface 2 is located opposite to the

    incident light rays both parabolic surfaces could be manufactured as a module. In this way the preciseness of the mutual location of both