Abstract:
A low head power generating system is disclosed including a wall pivotably attachable to a structure for moving between a generally upright position and a generally flat position. In the upright position, the structure or wall impounds water, and has a power generating cell connected to the wall, which rotates by movement of water there-through and is operably connectable to a generator for generating power. A support braces the wall in the upright position. The support is adjustable with a first end connected to the wall and a second end extended against a structure, and can be an inflatable bladder, a pressurized piston or other mechanism to move the wall. The cell can be mounted on the surface of the wall or integrated within the wall.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 61/482,256 filed May 4, 2011, which is incorporated as if fully set forth herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to low head hydropower facilities, and more particularly to a moveable element and power generation system for low head facilities. 
     2. Description of Related Art 
     Of the approximately 80,000 dams in the United States, about 2,500 of them produce some electricity. There is, therefore, a large inventory of non-hydropower producing dams. At these dams, water is released either continuously, or on an intermittent to regular basis for, among other things, flood control or irrigation purposes. Usually, governments and municipalities do not want anything to interfere with releasing water from the dams or reservoirs, or interfere with water movement downstream. Accordingly, anything fixed in the flow path of the water that might interfere with downstream water movement is undesirable to them. Previous solutions to increasing gross head pressure, which increases the potential for power generation, have involved moveable walls or flashboards that are deployed on the top of an existing dam structure to increase the gross head on a temporary basis. 
     Wicket-type gates have been utilized for navigation dams for over 100 years. These gates are often considered for navigable dam spillways, but they also function as non-navigable spillways. The gates can be lifted into position with a hydraulic or pneumatic cylinder applying force to the downstream side or with a gearbox. The wickets are generally held in an up position with a prop or strut that slides in a track on the lower pool side of the wicket. This allows the cylinder piston to be retracted, or extended during operating cycles. 
     These systems, however, are not intended for power generation, but to increase the height of the blocked water in the upper pool, thereby creating a larger gross head pressure. In some cases, the top of the existing dam is raised by these temporary walls and existing turbines positioned at the base of the dam receive increased head pressure which results in higher power production than without the higher gross head. However, none of these systems allow for the situational use of hydropower in a deployable system that may be placed in virtually any environment where low head is available while at the same time having the ability to let water pass over the turbine powerhouse during flooding events so that the turbine powerhouse does not reduce the flow of flood waters on the dam or dam spillway. Nor do any of these systems allow for a variety of combinations of turbines and movable walls to create interchangeable power generating cells and enhancements. 
     BRIEF SUMMARY OF THE INVENTION 
     An advantage of the present invention is to provide a system for converting low head dams into hydropower facilities, while still allowing near maximum discharge during flood events of the dam. 
     Another advantage of the present invention is to provide a system for converting low head dams into hydropower facilities while providing minimal interference with water flow during floods. 
     A further advantage of the present invention is to use a wicket gate type dam with integrated and interchangeable cells to convert moving water to electricity, and a variety of mechanical methods to raise and lower moveable elements. 
     Another advantage of the present invention is to provide a system that uses a hydropower turbine attached to a movable element that increases available gross head pressure. 
     In accordance with a preferred embodiment of the present invention, there is shown a low head power generating system having a wall pivotably attachable to a structure for moving between a generally upright position and a generally flat position wherein the structure impounds water, and a power generating cell connected to the wall rotatable by movement of water there-through and operably connectable to a generator. 
     In accordance with another embodiment of the invention, there is shown a low head power generating system having a pivotable wall that pivots between an operable position and an inoperable position movably attached to the top of a structure that impounds water when in the operable position, a turbine disposed in the wall rotatable by the impounded water as it moves across the turbine wherein the turbine is operably connectable to a generator, and a supporting member for bracing the wall when in the operable position. 
     In accordance with another embodiment of the invention, there is shown a low head power generating system having a pivotable wall fixedly attachable to the top of a structure that pivots between a generally upright position and a generally flat position wherein the structure impounds water creating an upper pool side, a power generating cell operably connected to the wall through movement of water and operably connectable to a generator, and a supporting member for bracing the wall when in the upright position. 
     Other objects and advantages will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, embodiments of the present invention are disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The novel features believed to be characteristic of the invention are set forth in the appended claims and claims yet to be filed. However, the invention itself, as well as a preferred mode of use and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying Figures wherein: 
         FIG. 1  is a side view schematic of a preferred embodiment of the present invention. 
         FIG. 2  is a side view schematic of another preferred embodiment of the present invention showing a knee brace and deployment of the invention. 
         FIG. 3  is a side view schematic of another preferred embodiment of the present invention showing an inflatable bladder. 
         FIG. 4  is a side view schematic of another preferred embodiment of the Present invention showing a pressurized piston. 
         FIG. 5  is an elevational view of another preferred embodiment of the invention showing a group of modular turbines, inflatable bladders, and raisable walls. 
         FIG. 6  is a side cross sectional view of  FIG. 5  taken along line  6 - 6 . 
         FIG. 7  is an elevational view of another preferred embodiment of the invention showing a series of moveable bladder raisable walls and modular turbine generator cells. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Detailed descriptions of the preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Various aspects of the invention may be inverted, or changed in reference to specific part shape and detail, part location, or part composition. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner. 
     Turning first to  FIG. 1 , there is shown a wall  21  having an integrated, interchangeable turbine and generator combination  25  disposed in wall  21  to create a power generating cell  20 . Cell  20  may be placed on the side of wall  21  or, in some embodiments, disposed completely flush into the wall. As illustrated more closely in the embodiment shown in  FIGS. 1 ,  2  and  3 , one end of wall  21  is connected to pivoting members  27  that permit wall  21  to be raised and lowered from approximately zero (0) degrees to approximately ninety (90) degrees. In some environments it may be preferable to raise wall  21  to more or less than ninety (90) degrees relative to the water surface of the upper pool  32 . In the illustrated figures, water lever is depicted as  32 . It will be appreciated that when wall  21  is raised, there exists an upper pool  33 , shown to the right of wall  21  in the figures, and a lower pool  34 , shown to the left in the figures. As can be appreciated, this is due to the natural direction of water flow and can be altered as the environment requires. 
     As further illustrated in  FIG. 1 , the lower end of wall  21  may be pivotally attached to a structure such as the top of dam wall  35  already in place, or to the top of the cell as shown in  FIG. 5 . The existing dam structure creates a certain amount of head pressure, which may be enhanced by placement of a series of cells  20  and walls  21  according to the present invention along a line transverse to the flow in the body of water. In other settings with no existing dam, the walls of the present invention may be supported by structures at the bottom of the water channel and deployed as needed to create a low head dam. 
     In one embodiment as shown in  FIG. 1 , where cell  20  is placed on the surface of the wall, there may be a reciprocal depression  30  in the structure or on the bottom of the water channel  37  to receive cell  20  when in a down or non-generating position. In this way wall  21  is protected during floods and does not present any impediment to the flow of water. 
     As appreciated by those of skill in the art, cell  20  is positioned below water lever  32  in the lower pool  34 , and thereby also below the water level  32  in the upper pool  33 . The exact position of cell  20  below the water level in the lower pool can be modified according to the desired result. 
     As will also be appreciated, wall  21  is illustrated in a particular position in the figures, though wall  21  may be raised or lowered according to the particular environment employed. In addition, the water level  32  on either side of wall  21  is illustrated only to show the level above cell  20  and is not depicted in any specific level as is needed for the instant invention. 
       FIG. 2  shows wall  21  on an embodiment of the present invention in two positions (a) and (b), along with knee brace  41  that may be employed to hold wall  21  in position while in the upright position, or any operable position between the zero (0) degree and ninety (90) degree position. First end  42  of knee brace  41  is connected to the upper portion  22  of wall  21  and second end  44  is moveably attached to the structure on the floor of the water channel  37  (shown in  FIG. 1 ) or the dam structure to which it is attached, similar to the embodiment illustrated in  FIG. 1 . Second end  44  may be connected to a rolling member that permits the second end  44  to move between one position where the wall is flat to a second position where the wall is upright in any of a number of positions from zero (0) degrees to approximately ninety (90) degrees and is shown in  FIG. 2  by the double-arrowed line, illustrating potential movement of second end  44  in both directions allowing movement of wall  21 . Second end  44  may be fixedly attached on the structure or dam to maintain the force on knee brace  41 , which in turn maintains wall  21  in a water blocking position. In the upright position (b) shown in  FIG. 2 , with knee brace  41  omitted for clarity, wall  21  creates a block, thus raising the level of water level  32  to create additional head pressure. This permits water to flow through cell  20 , thus generating power. 
     In an alternate embodiment as shown in  FIG. 3 , inflatable bladder  51  may be deployed on the downstream side of wall  21  to raise and lower wall  21  into an operable position, two potential positions of which are shown as (a) and (b). Bladder  51  may be filled with a pressurized fluid such as water or a hydraulic oil system, but may also include air, for increasing the size of the bladder and in turn raising and lowering wall  21  as desired. Similar to  FIG. 2 , wall  21  may be placed on the top of an existing dam or along the bottom surface of the body of water. Another embodiment includes having the wall  21  connected to the top of the cell  20  with the turbines connected to the existing dam as shown in  FIG. 5 . A series of such walls  21  may be employed to create a kind of moveable dam that creates a low head power generating station. The water that would otherwise be blocked by the wall flows through cells  20 , thereby generating power. 
     In another alternate embodiment shown in  FIG. 4 , second end  44  of knee brace  41  may be attached to a pressurized piston  47  that in turn raises and lowers wall  21  upon activation. 
       FIG. 5  shows a series of modular bladder raisable wall and turbine combinations that may be employed in an existing dam. Bladders are labeled  51 , similar to those illustrated in  FIG. 3 , while turbine and generator combination are labeled  25  similar to those in  FIG. 1 . Also similar to  FIG. 1 , dam wall  35  is shown. Turbine and generator combinations  25  are positioned to receive head power from the existing dam, but have placed on top of them an additional head producing wall  21 . 
       FIG. 6  shows a cross section view of  FIG. 5  taken along line  6 - 6  and illustrates that wall  21  is raisable in this embodiment with bladder  51  as previously described to create additional head. The power generating cell depicted in  FIGS. 5 and 6  may be preexisting within a dam structure or added to an existing dam. 
       FIG. 7  shows a series of bladders  51  and walls  21  that may be moveable and placed in various positions with fixed turbine and generator combinations  25 , or in combination with moveable turbine and generator cells depending on the circumstances. Any combination of power generating cell and raisable wall may be employed depending on the existing dam, the terrain, or flow characteristics of the body of water. As shown in  FIG. 7 , the inflatable bladder module may be inserted in different positions among the turbine generator cells. In alternative embodiments, the turbine and generator cells may also be moveable and configured with moveable walls to achieve the desired power from the body of water. 
     As noted above, the individual cells may be configured as part of the moveable wall as shown in  FIGS. 1-4 , and be designed for modular placement in or alongside an existing dam structure. 
     In any of these embodiments, the wall may be disposed on the bottom surface of the water body, on the top of a turbine cell or on the top of an existing dam structure for the purpose of creating additional head. The turbine and generator cell upon activation of the wall are thus engaged with sufficient gross head to turn the turbine and create power. By deploying a series of these walls across a body of water, power may be generated without interfering with the current flow of the body of water. Further, in the event of a flood or other need to clear the water channel of debris or ice, these walls may be lowered and placed in such a position as to not interfere with navigation or otherwise impede the flow of water. 
     While the invention has been described in connection with preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims, and claims that may issue.