Abstract:
A concentrator-driven, photovoltaic power generator system and method for capturing and transmitting electromagnetic radiation utilizing a reflector having a concave reflecting surface for concentrating electromagnetic radiation to a focal point.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a novel and useful solar energy collector system, more particularly a concentrator-driven, photovoltaic power generator for conversion of solar electromagnetic energy to electrical energy. 
       BACKGROUND OF THE INVENTION 
       [0002]    Solar energy has served as a means for generating electricity and heat at an accelerated pace. Although solar energy comprises a very abundant source, conversion to useable forms of energy is expensive. 
         [0003]    In the past, many systems have been devised to capture solar radiation. For example, solar panels have been employed in fixed arrays to directly convert solar radiation to electricity. In addition, circulation membranes have been employed to heat water for use within buildings and for use in swimming pools and spas. Other systems employ concave reflectors that concentrate solar radiation substantially at a point, where it is then employed to heat materials or is transferred as light to secondary conversion apparatuses. 
         [0004]    For example, U.S. Pat. Nos. 4,841,946 and 5,540,216 show concave solar power collectors which track movement of the sun and convert the solar radiation into heat. 
         [0005]    U.S. Pat. No. 5,877,874 shows a holographic planar concentrator which collects optical radiation from the sun for conversion through photovoltaic cells into electrical energy. Also, fiber optic light guides transfer collected light to an interior of a building for illumination or for the purpose of producing hot water. 
         [0006]    U.S. Pat. No. 5,581,447 shows a solar skylight apparatus in which light is collected from the sun and transmitted to the inside of a building through a fiber optic cable. The light is then dispersed within a room to provide illumination. 
         [0007]    U.S. Pat. Nos. 4,943,125 and 5,575,860 show solar collectors that employ fiber optic fibers for use as energy sources. 
         [0008]    A solar collection device which is efficient, powerful, and simple in construction would be a notable advance in the field of solar energy production. 
       SUMMARY OF INVENTION 
       [0009]    The present invention is a novel and useful collection device for capturing and transmitting electromagnetic radiation received from the sun. The present invention incorporates a solar collector, lens(es), an infrared (IR) filter, and photovoltaic cell. Incoming solar radiation striking the face of the parabolic solar collector is reflected and concentrated at the focal point. As the radiation begins to diverge from the focal point, it enters a concave plano lens, from which it exits as a concentrated beam. This beam then passes through an infrared filter, which screens out the infrared portion of the solar spectrum, thus preventing heat damage to, and loss of efficiency of, the photovoltaic cell. The concentrated photon rich visible light portion of the spectrum then strikes and activates the photovoltaic cell, thus generating a flow of electrical energy. 
         [0010]    The device of the present invention utilizes a reflector having a concave reflecting surface. The parabolic reflector is in general known to those skilled in the art. In such reflectors, essentially parallel rays of solar radiation are focused and concentrated at the focal point, thus, intensifying the radiation captured. The reflector is mounted on an existing-type tracking system which is also known in the art; or a novel, custom tracking system, to keep the reflecting surface in direct alignment with the sun from dawn to dusk, as the sun moves across the sky, thereby maximizing power output. 
         [0011]    An intermediary concave-plano lens is disposed at approximately the focal point of the parabolic reflector. The curvature of the concave side of the lens is the same as the curvature of the parabolic curved concave reflector. The concave side of the lens faces the reflector and the plano side of the lens faces the IR filter and the photovoltaic cell. The plano-concave lens converts the converging electromagnetic radiation into a concentrated, parallel-beam of visible-wavelength, electromagnetic radiation. 
         [0012]    In order to eliminate heat from infrared radiation, an infrared (IR) filter is placed between the plano-concave lens and the photovoltaic cell. 
         [0013]    It may be apparent that a novel and useful collection device for capturing and converting electromagnetic radiation described avoce. 
         [0014]    It is therefore an object of the present invention to provide a collection device for capturing and converting visible-wavelength, electromagnetic radiation radiating from the sun into electrical energy that is simple to manufacture and to operate. 
         [0015]    Another object of the present invention is to provide a device for capturing and converting electromagnetic radiation from the sun into electrical energy in an efficient manner. 
         [0016]    A further object of the present invention is to provide a collection device for capturing and converting electromagnetic radiation that is suitable for congested or urban areas. 
         [0017]    A further object of the present invention is to avoid overheating or otherwise damaging the photovoltaic cell during transmission of focused electromagnetic radiation into electrical energy by using an infrared (IR) filter. 
         [0018]    The invention possesses other objects and advantages especially as concerns particular characteristics and features thereof which will become apparent as the specification continues. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a representative side view of the concentrator-driven, photovoltaic power generator  100  of the present invention. 
           [0020]      FIG. 2  is a representative sectional view of the concentrator-driven, photovoltaic power generator  100  of the present invention. 
           [0021]      FIG. 3  is a schematic view of the mechanism of energy conversion/storage sub-system  200  of the present invention. 
           [0022]      FIG. 4  is a schematic view representing transduction of solar energy into electricity. 
       
    
    
       [0023]    For a better understanding of the invention reference is made to the following detailed description of the preferred embodiments thereof which should be taken in conjunction with the prior described drawings. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0024]    The description that follows is presented to enable one skilled in the art to make and use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principals discussed below may be applied to other embodiments and applications without departing from the scope and spirit of the invention. Therefore, the invention is not intended to be limited to the embodiments disclosed, but the invention is to be given the largest possible scope which is consistent with the principals and features described herein. 
         [0025]    Various aspects of the present invention will evolve from the following detailed description of the preferred embodiments thereof which should be taken in conjunction with the hereinabove delineated drawings. 
         [0026]    The present invention as a whole is shown in the drawings by reference character  100 , and any upper case letter to represent various embodiments thereof. With respect to  FIG. 1 , concentrator-driven, photovoltaic power generator  100  consists of a parabolic-shaped reflector  12  and a mobile stand  102 . Specifically, reflector  12  takes the form of a parabolic mirror having an inner reflecting surface  14  and an outer surface  16  which is generally non-reflective. In essence, reflecting surface  14  captures or gathers incoming parallel rays  18  from the sun. Reflecting surface  14  then reflects and focuses converging reflected rays  22  to the focal point  20 . Reflected rays  22  indicate such concentration of electromagnetic radiation to focal point  20 . As shown in  FIGS. 1 and 2 , a twice-bent hollow support tubing  150  or equivalent extends from the center of reflector  12  and provides anchor points for the electromagnetic radiation collection/storage system  200 . 
         [0027]    As shown in  FIG. 1 , reflector  12  is supported and elevated by mobile stand  102 . In one embodiment, mobile stand  102  may be of a conventional configuration to provide a sturdy and stable base for reflector  12  in the outdoor environment. Reflector  12  is anchored, fixed, and pivots mechanically, flexibly and adjustably on mobile stand  102 . Mechanical coupling device  105  such as a hinge, ball-and-socket joint, universal joint, etc., permits reflector  12  to rotate and move about its center point. This allows a controllable range of two-dimensional motion such that it is capable of tracking the sun as it travels across the sky on a daily orbital basis. Mechanical device  105  can be manually operated or controlled with an electrical/electronic motor. Support stand  102  can be mobile with wheels or other means such as wheels-and-track system  130  so the entire power generator  100  can be moved or relocated to locations that are most receptive to strong sun exposure. Since such two-axis tracking system supports are known in the art, mobile stand  102  is only partially shown in the drawings. In one embodiment, physical locations of the present invention  100  in the wheels-and-track system  130  and titling angles of reflector  12  can both be pre-programmed according to locations of the sun during the day/year. 
         [0028]      FIG. 2  is a representative sectional view of the concentrator-driven, photovoltaic power generator  100  of the present invention.  FIG. 3  is a schematic view of the mechanism of concentrator-driven, photovoltaic power generator  200  of the present invention. Referring to  FIG. 3 , the concentrator-driven, photovoltaic power generator  200  consists one or more intermediary lens assembly  106 , infrared filter device  108  and photovoltaic cell  112 . The three elements of the concentrator-driven, photovoltaic power generator  200  are installed and supported securely by each of its support stands  152 ,  154  and  156  on the twice-bent hollow support tubing  150  which extends from the center of reflector  12 . In one embodiment, the three elements are disposed in a straight line sequence of intermediary lens assembly  106 →infrared filter device  108 →photovoltaic cell  112  with the intermediary lens assembly positioned closest to reflector  12 . The intermediary lens assembly is positioned at the focal point  20  where all converging reflected rays  22  from reflector  12  are gathered. In one embodiment, support tubing  150  is a hollow tubing that has a squarish cross-section and is made of steel, plastic, silicon or other sturdy and yet strong materials. It will be understood by those skilled in the art that support tubing can be substituted with equivalent structural components for achieving the same function. 
         [0029]    In one embodiment, intermediary lens assembly  106  which is a type of optical lens fixed at the focal point  20 , where the converging reflected rays or concentration of electromagnetic radiation  22  enter intermediary lens assembly  106 . Intermediary lens assembly  106  can be in the form of a lens or a lens assembly that alters the converging reflected rays or concentration of electromagnetic radiation  22  into a concentrated, uni-directional flow of solar energy  110 . The optical characteristics such as focal length, shape, i.e., concave, convex or combination thereof, etc., of intermediary lens assembly  106  can be adjusted according to the true dimension of the power generator  100 . In one embodiment, parallel rays  18  from the sun are reflected by reflector  12  to become converging rays  22  at focal point  20 . The main purpose of reflector  12  is to concentrate the energy of parallel rays  18  at focal point  20  for effective energy collection. Subsequently, at and around focal point  20 , converging reflected rays  22  pass through intermediary lens assembly  106  and emerge as a concentrated, uni-directional flow of visible-wavelength solar energy  110 . The present invention minimizes energy loss due to internal reflection or other reasons. 
         [0030]    In one embodiment, intermediary lens assembly  106  is movably fixed to support tubing  150  by its support stand  152  such that the position of the intermediary lens assembly  106  can be adjusted in order to be located at or as close to the focal point  20  as possible for maximum efficiency. Since it is possible that a portion of the uni-directional flow of solar energy  110  will contained energy in the infrared wavelength-range, the system could develop overheating problems. Thus, the uni-directional flow of solar energy  110 , i.e., parallel radiation, leaves intermediary lens assembly  106  and enters infrared filter device  108 . 
         [0031]    Infrared filter device  108  is an infrared cut-off filter, sometimes called an IR filter or heat-absorbing filter. In one embodiment, infrared filter device  108  is movably fixed to support tubing  150  by its support stand  154 . The purpose of infrared filter device  108  is to block infrared wavelength-radiation in the uni-directional flow of solar energy  110  while passing uni-directional flow of filtered solar energy  120  to prevent overheating when it enters photovoltaic cell  112 . In alternative embodiments, other types of filters such as UV filter or other wavelength-specific filters can be added or replaced as needed. 
         [0032]    Filtered uni-directional flow of solar energy  120 , i.e., parallel radiation, leaves infrared filter device  108  and enters photovoltaic cell  112 . Photovoltaic cell  112  is a device that converts the photonic energy of incoming filtered visible wavelength, uni-directional flow of solar energy  120  directly into electricity by the photovoltaic effect. In one embodiment, photovoltaic cell  112  has various electrical characteristics e.g. current, voltage, or resistance to suit specific needs of the present invention  100 . Generally, when photovoltaic cell  112  exposed to uni-directional flow of solar energy  120 , it generates and supports an electric current without the need for any external power source. 
         [0033]    In one embodiment, photovoltaic cell  112  is movably fixed to support tubing  150  by its support stand  156 . Photovoltaic cell  112  is also connected to an electric circuit so the electrical energy generated within can be transmitted to remote locations. In one embodiment, the electric circuit can be installed within the hollow support tubing  150  or other configurations. As best shown in  FIG. 4 , in one embodiment, photovoltaic cell  112  converts energy from filtered uni-directional flow of solar energy  120  into electrical energy denoted by electrical potential  402 . Electrical potential  402  can be coupled to a capacitor or used to recharge batteries for storage of the electrical energy generated, as desired. Alternatively, the energy potential  402  can be used to power electrical devices directly. Users can also connect energy potential  402  to a more elaborate electrical circuit with other electrical components such as transducers, transformers, etc. for other purposes, or provide electrical power to the grid, i.e., puts power back into a private or general municipal electrical power system. 
         [0034]    While in the foregoing, embodiments of the present invention have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, it may be apparent to those of skill in the art that numerous changes may be made in such detail without departing from the spirit and principles of the invention. 
         [0035]    Although the invention herein is to be understood as described, these descriptions are merely illustrative of the principles and applications of the present invention. Therefore, it is understood that numerous modifications may be made to the illustrative embodiments and that other modifications maybe devised without departing from the scope and functions of the inventions as defined by the claims to be followed. 
         [0036]    Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications and patent documents referenced in the present invention are incorporated herein by reference. 
         [0037]    While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, with the limits only of the true purview, spirit and scope of the invention.