Abstract:
A solar heater comprises one or more portable panels for collecting heat from the sun and providing it to a space to be heated. The panels include collector plates within a double glazed frame. The collector plate is formed of black corrugated steel, and heats up quickly in the sun. A blower blows air into an input manifold and across the collector plate, perpendicular to the corrugations, and the heated air exits via an output manifold. A sensor controls when the blower operates.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to portable panels for heating forced air with solar radiation. 
         [0003]    2. Description of the Related Art 
         [0004]    Solar energy is very effective for heating living and working spaces. Passive solar heating, such as sun falling on a roof or window, will heat the space inside. But to effectively heat the inside space, at selected times, apparatus is required. 
         [0005]    Active solar heating systems use electrical or mechanical equipment to increase the amount of usable solar heat provided to the space to be heated (generally called living space, although it includes garages and offices and the like). For example, fans might deliver heated air to the living space. 
         [0006]    Photovoltaic array may also be used for heating, but converting sunlight into electricity and then back to heat is inefficient. However, the ability to store the energy in a battery is an advantage. 
         [0007]    A need remains in the art for improved active solar heating panels for providing heat to a living space. 
       SUMMARY 
       [0008]    An object of the present invention is to provide active solar heating panels for providing heat to a living space. Individual solar heating panels according to the present invention are generally portable, and are configurable into arrays. 
         [0009]    Each solar panel includes a frame with a panel backing for retaining a collector sheet and glazing to allow the sun to reach the top surface of the collector. The collector sheet is generally parallel to the backing and the top layer, and spaced apart from each. 
         [0010]    The frame includes side walls. An input side wall includes air holes for air to enter the panel, and an output side wall includes air holes for air to exit the panel. The collector plate bisects the input and output air holes such that air travels over both the top surface and the bottom surface of the collector plate. 
         [0011]    As a feature, the collector plate may be textured to increase turbulent airflow. The collector plate is generally black and may comprise corrugated steel. 
         [0012]    The glazing may include an acrylic glass (such as Plexiglas®) outer layer and a regular window glass inner layer (e.g. silicate glass). The acrylic glass protects the glass from the elements, while the window glass is cheaper and stands up to the high internal temperatures of the panel better. Alternatively, the outer layer could comprise safety glass or tempered glass or the like. 
         [0013]    The frame may be composed of composite and include grooves for holding the collector sheet and glazing layers in place. 
         [0014]    The solar panels are designed to be configured into arrays. Straight-through panels have air holes on opposing sides, while corner panels have air holes on adjacent sides. 
         [0015]    Air is forced into air holes in an entrance panel on one side of the array, travels through each panel in turn, and exits through air holes in an exit panel. 
         [0016]    Equipment for forcing air through the array may include a fan, input and output air manifolds, and tubing. A temperature sensor monitors air leaving a panel or array and provides data to a control unit, which controls the fan according to the data. Power to the fan might be provided via an electrical outlet, a battery, a photovoltaic cell, or the like. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is an isometric view of a solar panel according to the present invention. 
           [0018]      FIG. 2  is a magnified section view of the panel of  FIG. 1 . 
           [0019]      FIG. 3  is a side view of an end of the panel of  FIG. 1 . 
           [0020]      FIG. 4  is an exploded isometric view of the panel of  FIG. 1 . 
           [0021]      FIG. 5  is plan view of a solar heater formed from multiple solar panels according to the present invention. 
           [0022]      FIG. 6  is a block diagram showing the present invention in use. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    The following reference numbers are used in the figures: 
         [0000]    
       
         
               
               
             
           
               
                   
               
             
             
               
                 100 
                 Solar panel - straight-through 
               
               
                 102 
                 Panel frame 
               
               
                 104 
                 Air holes 
               
               
                 106 
                 Acrylic glass panel 
               
               
                 108 
                 Glass panel 
               
               
                 110 
                 Collector sheet 
               
               
                 112 
                 Panel backing 
               
               
                 114 
                 Acrylic glass panel groove 
               
               
                 116 
                 Glass panel groove 
               
               
                 118 
                 Collector sheet groove 
               
               
                 119 
                 Recess for backing 
               
               
                 120 
                 Panel sides with air holes 
               
               
                 122 
                 Panel sides without air holes 
               
               
                 130 
                 Multipanel heating unit 
               
               
                 132 
                 Input air manifold 
               
               
                 134 
                 Output air manifold 
               
               
                 136 
                 Gasket 
               
               
                 140 
                 Solar panel - corner 
               
               
                 150 
                 Fan 
               
               
                 152 
                 Input tubing from fan 
               
               
                 158 
                 Input air from fan 
               
               
                 160 
                 Output heated air from unit 
               
               
                 162 
                 Air path 
               
               
                 170 
                 Heater 
               
               
                 172 
                 Temperature sensor 
               
               
                 174 
                 Control signal from heating unit 
               
               
                 176 
                 Control signal from heated space 
               
               
                   
               
             
          
         
       
     
         [0024]      FIG. 1  is an isometric view of an exemplary single straight-through solar panel  100  according to the present invention. Panel  100  includes a frame  102  having air holes  104  through which air will enter and leave the panel. Frame  102  includes sides  120  with air holes and sides  122  without air holes. Panel  100  is preferably double glazed with a layer of acrylic glass  106  and a layer of glass  108 . The top panel  106  is acrylic glass to resist hail and other damage. Acrylic glass is 10 times stronger than glass. The interior glazing layer  108  is glass to resist heat better and because it is cheaper. Beneath the glazing  106 ,  108  is a collector sheet  110  of black corrugated steel for collecting heat from the sun. Beneath sheet  110  and attached to frame  102  is backing  112 . 
         [0025]    Corrugated sheet  110  is preferably generally centered with respect to air holes  104 , so that air flows over and under sheet  110 . The corrugations run perpendicular to the airflow to cause turbulent airflow and increase heat transfer. 
         [0026]      FIG. 2  is a magnified section view of a side  122  of panel  100 . Side  122  forms grooves  114 ,  116 ,  118  for holding glazing  106 ,  108  and corrugated sheet  110  respectively. Backing  112  is affixed to the bottom of panel  102  in recess  119 . 
         [0027]      FIG. 3  is a side view of frame  102  side  120 . Side  120  includes air holes  104  and grooves  114 ,  116  and  118 . Preferably, a recess  119  is formed in the bottom of side  120  for insertion of backing  112 . 
         [0028]      FIG. 4  is an exploded isometric view of panel  100 . Frame  102  is formed of sides  120  having air holes and sides  122  without air holes. In the straight-through panel  100 , two sides  120  with air holes are positioned opposite to each other. Ambient air  158  will enter one side  120  via air holes  104 , pass over corrugated sheet  110  perpendicular to the direction of the corrugations, and exit panel  100  through the second side  120  through its air holes  104 .  FIG. 4  also shows how panel  100  might be assembled. Glazing  106  and  108  is fitted into grooves  114  and  116 . Corrugated sheet  110  is fitted into groove  118 . Sides  120 ,  122  are then fastened together, for example with glue or nails, forming frame  102 . Then, backing  112  is affixed to the bottom of frame  102 . 
         [0029]    In a preferred embodiment, each panel  100  is portable, i.e. compact and light enough to be carried and installed by a single person. For example, Panel  100  is two feet square and 3 inches thick. It weighs about 20 pounds. Frame  102  is formed of a light tough material such as the weatherproof composite used for decking. The frame is ¾ inch thick. Air holes  104  are 1¼ inch in diameter. Collector plate  110  is corrugated steel with 1¼ inch corrugations, and is painted black on the top surface (facing the glazing). Backing  112  is tempered masonite, ⅛ inch thick. 
         [0030]    Panels  100  are tough and portable. Panels manufactured as described above have been tested to temperatures above real world conditions, intense rain and snow, and direct sunlight without failures. Panels dropped from heights of less than 6 feet generally have unharmed frames, though the window glass layer breaks around 25% of the time (the broken glass was contained within the panel structure in these cases). 
         [0031]      FIG. 5  is plan view of a solar heater formed from multiple solar panels  100 ,  140 . Corner panels  140  are similar to straight-through panels  100 , except that sides  120  with air holes  104  are adjacent to each other instead of across from each other. Hence input air  158  enters manifold  132 , follows path  162  through heater  130  and exits manifold  134  as heated airflow  160 . A thin rubber gasket  136  between each connected panel  100 ,  140  seals airflow within heater  130 . 
         [0032]    Those skilled in the art will appreciate that panels  100 ,  140  may be connected in various combinations as heating requirements dictate and space allows. For example, several straight-through panels  100  may be connected in a row where a long narrow space is available. A heater may be formed of a single panel (see  FIG. 6 ) or two or several. A four-panel array has been observed to raise air temperature 35 degrees at 120 CFM. An array of six panels provides about half of the heat needed for a 400 ft 2  room or garage, if no heat storage system is used. As an option, a heat storage system for storing heat during the day for use at night might comprise storage modules, for example 2 foot cubes made of weatherproof composite boxes filled with recycled concrete broken into first sized chunks. The boxes connect together with short pieces of flex duct and are ducted back to the blower box, where dampers control the flow of air to charge them up with heat during the daytime and recover the heat at night. 
         [0033]    The storage modules could be stacked in a basement, assembled outside along a wall, or even placed on the uneven ground under a mobile home. 
         [0034]    Panel arrays may be mounted on any sunny wall or roof or on a rack. Panels may be arrayed around a window or along the skirting of a mobile home. Each array includes an input manifold  132 , connected to blower  150 , and an exit manifold  134  for providing heated air  160  to the space to be heated, for example via a flexible duct (not shown). Panels  100 ,  130  may be adjacent to each other as shown in  FIG. 5 , or they may be connected via tubing. In the latter case each panel includes manifolds  132 ,  134 . 
         [0035]      FIG. 6  is a block diagram showing the present invention in use. A blower  150  provides input airflow  158  to heater  170 , comprising a single straight-through panel  100 , via tubing  152  and input manifold  132 . Heated exit airflow  160  exiting heater  170  is available for use in heating. 
         [0036]    Blower  150  may be mounted in a box designed to insert into a window much like a standard window air conditioner. It could mount horizontally on the sill of a double or single hung window, or vertically in a slider. It could also be installed in an opening cut into the exterior wall if the user so desires. If the user wants to cut openings in the roof to run the ducts through, blower  150  could even be mounted on an interior wall anywhere in the building. Blower  150  might comprise a 120 volt squirrel cage model which plugs into any interior outlet. An optional 12 volt DC model is powered by a photovoltaic panel (not shown). This would allow use of the system anywhere in the world and when a power outage occurs as long as it is exposed to sunlight. The blower moves up to 250 CFM of air and is controlled by a variable speed switch. Sensor  172  near or within discharge manifold  134  of heater  100  prevents heated air  160  from entering the space to be heated when the temperature  174  in heater  100  is lower than the current temperature  176  of that space. In one embodiment, sensor  172  prevents fan  150  from running if the temperature of the air in heater  100  falls below 95° F. As a feature, a bypass switch may be provided so the owner can draw cooler air if desired. 
         [0037]    It will be appreciated by one skilled in the art that there are many possible variations on these designs that fall within the scope of the present invention.