CASCADE UTILIZATION OF SUNLIGHT ENERGY

Abstract: The invention relates to a device for supporting and protecting solar cells, preferably of the thin film variety, for application in various types of buildings. The solar cells (3) are mounted directly on elongated beams (2), parallelly orientated at a predetermined distance from each other and placed on their edge, in said beams (2) there are channels (4) for cooling and removal of produced heat by means of a circulating gas, liquid or a solar heated vaporizeable medium, which later is condensed in a heat storage space, said beams (2) with attached solar cells (3) being protected by at least one transparent, outer cover (1) of plastic or glass, arranged over them, at the time as the lower parts of the beams (2) by means of hinges (5) support up-and-down movable panels (6, 7).

Description: Cascade utilisation of sunlight energy. The present invention refers to a device to support; and protect solar cells preferably of the thin film variety for application in various types of buildings thereby permitting a cascade utilization of solar energy. Increased efficiency of solar cells of the thin film variety and improved possibilities for large scale production both of CIS- and Gratzelcells , brings up the question of how such cells can best be integrated with the climatizing- , illumination- and recycling systems in differnt types of buildings . A natural starting point is then not only to protect those delicate cells agains rain, snow, ice and dust, but also to prevent a heating which could reduce the efficiency of the cells. The object of the present invention is now to effect an efficient protection of those delicate cells against rain, snow, ice and dust and also to prevent a heating which reduces their efficiency. In this connection it is characteristic for the invention that the solar cells are mounted directly on beams included in the device, said beams are longitudinal and placed on their edge and parallelly orientated at a predetermined distance from each other, in said beams are channels for cooling and for removal of produced heat by means of a circulating gas, liquid or a solar heated vaporizeable medium, which later is condensed in a heat storage space. The beams with attached solar cells are protected between a transparent, outer cover of plastic or glass and and an under- roof also of a transparent material, said under-roof constitutes the upper limit of a space, the floor of which serves as a heat storage at the same time as the lower parts of the beams by means of hinges support up-and-down movable panels. In a preferred embodiment form of the invention the movable panels have a height which corresponds to half the distance between the beams. In addition the panels can be manufactured from reflecting and insulating material and be positioned by means of a special guide-program . The invention is described below in more detail by means of a preferred embodiment example, which refers to the attached drawing, which shows a schematic partial cross section of the device according to the invention. In accordance with the invention the drawing shows a preferred embodiment example of a shelter for solar cells 3 formed such as a transparent outer shell 1, preferably of plastic or glass, over hollow, vertical beams 2, for instance made of black anmodized aluminium, on which solar cells 3 have been attached, and an under-roof 8 arranged under the beams 2 preferably a plastic foil. By this arrangement the solar cells 3 can efficiently be cooled by means of a gas or non-freezing liquid medium, which circulates through channels 4 in the beams 2, from which any medium selected for evaporation by solar heat can reach a heat storage space for condensation and subsequent recycling. In this way not only electricity but also heat can be stored, which makes it possible to balance the needs for electricity, heating/cooling and illumination under a so-called "climate shell". This can be achieved by heat pump technology and elongated, movable panels 6, 7, which are mounted on hinges along the lower edge of the vertical beams 2. The panels 6, 7, which can be elongated, movable shiny screens, are intended to reflect sunlight towards the solar cells 3. They are manufactured from a heat insulating material and their positioning 9 is guided according to an earlier known principle which is described in detail in United States patent 4,733,506. The lower edges of the beams 2 provide a hold for said under-roof 8 formed by a plastic foil, which protects the space below from downdraft, at the same time as said under-roof 8 acts as a shield against dust and represents the ceiling of a space, the floor of which acts as a heat storage space. The panels 6, 7 with their reflecting surfaces, which during the night are intended to prevent heat losses, are caused to assume positions 9 during the daytime, giving an optimal distribution between el-heatstorage, indoor illumination and comfort This creates new conditions for climate shells, which for instance make it possible to control a local water management and various organic waste cycles. The positions 9 of the panels 6, 7 can be determined by a guide- program, which continuously optimizes the balance between electricityy production, climatizing and illumination - by integrating object-specific data (the geographic locationt : lat . - long, the compass direction of the transparent surfaces, the basic building geometry, the annual climate profile and the costs for external energy inputs) with the time, date and other local and momentary conditions such as the difference between the outdoor and indoor temperatures and remaining heat storage capacity. The optimizing problems are of different types namely technical and economical and their solution provides good opportunities to penetrate different markets, where good illumination can be combined with enclosed modularized units suitable for industrial production. The latter can be very simple and flexible since they need not involve considerations of snowloads, windpressures and barrier needs, which normal buildings require.

Claims: Claims 1. A device for supporting and protecting solar cells, preferably of the thin- film variety, for use in various types of buildings, characterized in that the solar cells (3) are mounted directly on elongated beams (2) , parallelly orientated at a predetermined distance from each other and placed on their edge, in said beams (2) there are channels (4) for cooling and removal of produced heat by means of a circulating gas, liquid or a solar heated vaporizeable medium, which later is condensed in a heat storage space, said beams (2) having the solar cells (3) being protected by at least one transparent, outer cover (1) of plastic and/or glass, arranged over them, at the same time as the lower parts of the beams (2) by means of hinges (5) support up-and-down movable panels (6,7) . 2. A device according to claim 1 , characterised in that the beams (2) with attached solar cells (3) are protected between the transparent outer cover (1) and an under-roof (8) also of a transparent material . 3. A device according to claim 1, characterized in that the movable panels (6,7) have a heigh corresponding to half the distance between the beams (2) . 4. A device according to claim 1, characterized in that the panels (6,7) are manufactured from a reflecting and heat insulating material . 5. A device according to claim 1, characterized in that the position of the panels (6,7) is adjustable by means of a guide- program . 6. A device according to claim 1, characterized in that the circulating medium is resistant to freezing.

Inventors: HEDEN CARL-GOERAN, HEDEN, CARL-GOERAN
Applicants: EKVITEC AB, HEDEN CARL GOERAN, HEDEN, CARL-GOERAN
Application year: 2000
Main classification: F24J2
IPC codes: F24J2, H01L31