Patent Publication Number: US-2015061293-A1

Title: Hydro-electric system and device for producing energy

Description:
FIELD OF THE INVENTION 
     This invention generally relates to an apparatus and system for producing energy. More specifically, to apparatuses and systems that utilize a falling volume of water to produce energy. 
     BACKGROUND OF THE INVENTION 
     Energy has been traditionally derived from the burning of fossil fuels, such as coal, oil and gas. However, an increasing demand for energy has resulted in the depletion of natural resources and increased cost for energy. Environmental concerns have also been raised over the release of harmful pollutants from using energy stored in fossil fuels. Nuclear power is another energy source, but there are concerns about safety and disposal of nuclear waste byproducts. Alternative sources of energy such as wind power and solar power are not presently believed to provide a cost effective and base load energy source on demand. 
     Hydro-electric energy is a safe, cost effective and renewable base load energy source. Hydro-electric power generation typically involves the use of falling water (either naturally occurring or dammed) to drive turbines which in turn drive generators to generate energy. However, the available sites in the world to utilize this resource have almost all been developed over the years. 
     Artificial falls of water may be created to mimic the capture of kinetic energy from falling water. Fallen water collected in artificial basins must be dispersed. However, energy is typically used to disperse the fallen water, which is inefficient. Water dispersion methods have been suggested such as the use of a pump, vacuum or water vaporization to remove the fallen water. 
     It would be desirable to provide an energy producing unit which requires less energy to disperse fallen water than that captured by the kinetic energy of the fallen water. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention, an energy producing unit is provided. A host structure is immersed in a main body of fluid. The host structure has at least one side wall open to the main body of fluid at a lower portion, and a horizontal wall having a horizontal wall valve. A chamber, having a bottom wall and at least one side wall, is fixed relative to the host structure. A moveable member has a first horizontal member disposed within the chamber, a second horizontal member disposed below the horizontal wall in the main body of fluid and at least one support connecting the horizontal members and passing through the horizontal wall. The moveable member is independently vertically movable relative to the host structure between a risen position and a lowered position. The moveable member is buoyantly biased to the risen position. The first horizontal member has a first horizontal member valve. The first horizontal member is disposed within the chamber to divide the chamber into an upper reservoir and a lower reservoir. When the first horizontal member valve is open, fluid may pass between the upper and lower reservoirs and when closed, prevents fluid communication between such reservoirs. An expandable compartment is formed between the at least one side wall of the host structure, the horizontal wall disposed at an upper portion of the expandable compartment and the second horizontal member of the moveable member. The expandable compartment expands and retracts when the second horizontal member of moveable member is vertically moved between the risen position and the lowered position. At least one side wall opening is disposed on the side wall of the host structure for permitting fluid located in the expandable compartment to flow into the main body of fluid. The side wall opening has a side wall opening valve for controlling the flow of the fluid into the main body of fluid. When the side wall opening valve is open, fluid may flow from the expandable compartment to the main body of fluid and when closed, the side wall opening valve prevents fluid communication. An inlet conduit has a lower end and an upper end. The inlet conduit passes through the at least one side wall of the host structure, and is open to the expandable compartment at the lower end and open to the exterior of the host structure at the upper end. The inlet conduit permits fluid located outside the host structure to flow into the expandable compartment. The inlet conduit has at least one inlet conduit valve for controlling the flow of the fluid into the expandable compartment. An energy extraction device is disposed within the inlet conduit to extract kinetic energy as fluid flows through the inlet conduit into the expandable compartment. An outlet conduit has a lower end and an upper end. The outlet conduit is in fluid communication with the lower reservoir at the lower end and in fluid communication to the upper reservoir at the upper end. The outlet conduit permits fluid located in the lower reservoir to flow into the upper reservoir. 
     When the moveable member is in the risen position, by opening the inlet conduit valve and horizontal wall valve, the expandable compartment fills with fluid. The moveable member sinks to the lowered position due to increased volume of the fluid in the expandable compartment and fluid in the lower reservoir flows into the upper reservoir via the outlet conduit. When the moveable member is in the lowered position, by closing the inlet conduit valve and horizontal wall valve, fluid flows from the expandable compartment to the main body of fluid by opening the side wall opening valve, and fluid flows from the upper reservoir to the lower reservoir by opening the first horizontal member valve, and the moveable member rises due to buoyant forces to the risen position. 
     The first horizontal member of the moveable member may have a first horizontal member fluid seal disposed between the first horizontal member and the chamber. 
     The second horizontal member of the moveable member may have a second horizontal member fluid seal disposed between the second horizontal member and the at least one side wall of the host structure. 
     The second horizontal member of the moveable member may have a second horizontal member valve to permit fluid located in the expandable compartment to flow into the main body of fluid, and control the flow of the fluid into the main body of fluid. When the second horizontal member valve is open, fluid may flow from the expandable compartment to the main body of fluid and when closed, prevents fluid communication. 
     A side conduit may be positioned in the side wall of the chamber in fluid communication with the lower reservoir at a lower end and in fluid communication to the upper reservoir at an upper end to permit fluid located in the upper reservoir to flow into the lower reservoir. The side conduit may have at least one side conduit valve to control the flow of the fluid into the lower reservoir. When the side conduit valve is open, fluid may flow from the upper reservoir to the lower reservoir and when closed, prevents fluid communication. 
     The moveable member may have at least one vertical wall disposed above the first horizontal member. 
     The outlet conduit may have at least one outlet conduit valve for controlling the flow of fluid into the upper reservoir. 
     A crane may be attached to the moveable member for controlling vertical movement of the moveable member in the risen position. 
     The energy producing unit may have a latch attached to the host structure for controlling vertical movement of the moveable member in the risen position. 
     The energy producing unit may have a counterweight attached to the moveable member to assist movement of the moveable member to the risen position. 
     The energy producing unit may have a motorized lift attached to the moveable member for controlling vertical movement of the moveable member. 
     The energy extraction device may be connected to a generator for generating electrical energy. 
     The side wall of the host structure may have at least one chamber wall duct to permit fluid communication between the chamber and the main body of fluid. The at least one chamber wall duct has a chamber wall duct valve to control fluid communication between the chamber into the main body of fluid. When the chamber wall duct valve is open, fluid is allowed and when closed, the chamber wall duct valve prevents fluid communication. 
     The host structure may have a bottom horizontal member forming a lower cavity below the moveable member. The bottom horizontal member has a bottom horizontal member valve to control the flow of fluid from the lower cavity into the main body of fluid. When the bottom horizontal member valve is open, fluid may pass between the lower cavity and the main body of fluid and when closed, prevents fluid communication. 
     The host structure may have a chamber horizontal member above the upper reservoir for permitting fluid located above the chamber horizontal member to flow into the upper reservoir, the chamber horizontal member having a chamber horizontal member valve for releasing fluid into the upper reservoir, such that when the chamber horizontal member valve is open, fluid may drain into the upper reservoir and when closed, the chamber horizontal member valve prevents fluid communication. 
     According to another aspect of the invention, an energy producing unit is provided. A host structure is immersed in a main body of fluid. The host structure has at least one side wall having openings to permit the main body of fluid to pass through the host structure, a bottom wall and a horizontal wall having a horizontal wall valve. A closed chamber containing chamber fluid is fixed relative to the host structure and disposed within the host structure. The chamber has a top wall, bottom wall and at least one side wall. A moveable member has first horizontal member disposed below the horizontal wall, a second horizontal member disposed within the closed chamber and at least one support connecting the members and passing through a scaled opening in the top wall of the chamber. The moveable member is independently vertically movable relative to the host structure between a risen position and a lowered position. The moveable member buoyantly biased to the risen position. The second horizontal member of the moveable member has a second horizontal member valve. The second horizontal member is disposed within the closed chamber to divide the closed chamber into an upper reservoir and a lower reservoir. When the second horizontal member valve is open, chamber fluid may pass between the lower and upper reservoirs and when closed, prevents fluid communication between such reservoirs. At least one latch located on the side wall of the host structure holds the moveable member in the risen position. An expandable compartment is formed within the host structure by the at least one side wall of the host structure, the horizontal wall and the first horizontal member of the moveable member. The expandable compartment expands and retracts when the first horizontal member of moveable member is vertically moved between the risen position and the lowered position. The first horizontal member of the moveable member has a first horizontal member valve for controlling fluid located in the expandable compartment to flow into the main body of fluid. When the first horizontal member valve is open, fluid may flow from the expandable compartment to the main body of fluid and when closed, the first horizontal member valve prevents fluid communication. An inlet conduit has a lower end and an upper end. The inlet conduit passes through the at least one side wall of the host structure, and is open to the upper portion of the expandable compartment at the lower end and open to the exterior of the host structure at the upper end. The inlet conduit permits fluid located outside the host structure to flow into the expandable compartment. The inlet conduit has at least one inlet conduit valve for controlling the flow of the fluid into the expandable compartment. An energy extraction device is disposed within the inlet conduit to extract kinetic energy as fluid flows through the inlet conduit into the expandable compartment. An outlet conduit has a lower end and an upper end. The outlet conduit is in fluid communication with the lower reservoir at the lower end and in fluid communication to the upper reservoir at the upper end. The outlet conduit permits fluid located in the lower reservoir to flow into the upper reservoir, and has at least one outlet conduit valve for controlling the flow of the fluid into the upper reservoir. 
     When the moveable member is in the risen position, by opening horizontal wall valve, the outlet conduit valve and the inlet conduit valve, the expandable compartment fills with fluid. The moveable member sinks to the lowered position due to increased weight of the fluid on the first horizontal member of the moveable member, and fluid in the lower reservoir flows into the upper reservoir. When the moveable member is in the lowered position, by closing the inlet conduit valve, horizontal wall valve and outlet conduit valve, and opening the first horizontal member valve and the second horizontal member valve, fluid flows from the expandable compartment to the main body of fluid via the first horizontal member valve, fluid flows from the upper reservoir to the lower reservoir, and the moveable member rises due to buoyant forces to the risen position. 
     The first horizontal member of the moveable member may have a first horizontal member fluid seal disposed between the first horizontal member and the at least one side wall of the host structure. 
     The second horizontal member valve of the moveable member may have a second horizontal member fluid seal disposed between the second horizontal member and the side of the chamber. 
     The energy producing unit may further comprise a counterweight attached to the moveable member to assist movement of the moveable member to the risen position. 
     According to another aspect of the invention, an energy producing structure is provided. The energy producing structure has at least two energy producing units. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional side view of an energy producing unit at a first stage of an energy production cycle, in accordance with a first embodiment of the present invention. 
         FIG. 2  is a cross-sectional side view of an energy producing unit at a second stage of an energy production cycle, in accordance with a first embodiment of the present invention. 
         FIGS. 3A-3B  are cross-sectional side views of an energy producing unit at a third stage of an energy production cycle, in accordance with a first embodiment of the present invention. 
         FIG. 4  is a cross-sectional side view of an energy producing unit at a fourth stage of an energy production cycle, in accordance with a first embodiment of the present invention. 
         FIG. 5  is a cross-sectional side view of an energy producing unit, in accordance with a first embodiment of the present invention. 
         FIG. 6  is a cross-sectional side view of an energy producing unit, in accordance with a first embodiment of the present invention. 
         FIG. 7  is a cross-sectional side view of an energy producing unit at a first stage of an energy production cycle, in accordance with a second embodiment of the present invention. 
         FIG. 8  is a cross-sectional side view of an energy producing unit at a second stage of an energy production cycle, in accordance with a second embodiment of the present invention. 
         FIGS. 9A-9B  are cross-sectional side views of an energy producing unit at a third stage of an energy production cycle, in accordance with a second embodiment of the present invention. 
         FIG. 10  is a cross-sectional side view of an energy producing unit at a fourth stage of an energy production cycle, in accordance with a second embodiment of the present invention. 
         FIG. 11  is a cross-sectional side view of an energy producing unit, in accordance with a third embodiment of the present invention. 
         FIG. 12  is a top plan view of an energy producing system, in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An energy producing unit is provided to capture kinetic energy of falling fluid into an empty chamber. The fallen fluid is dispersed efficiently by using less energy than that captured by the extraction device. The extracted energy may be connected to a generator to produce electricity or serve as an energy source. 
       FIGS. 1 to 4  illustrate a cross-sectional view of an energy producing unit  102  at various stages of an energy production cycle according to one embodiment of the present invention. The energy producing unit  102  has a host structure  104  comprised of at least one sidewall and a horizontal wall  110 . The host structure  104  is immersed in a fluid  106 . The at least one side wall is open to the fluid at a lower portion. A chamber  108  comprised of a bottom wall and at least one side wall is fixed relative to the host structure  104 . 
     A moveable member  120  is located within the host structure  104  and is independently vertically moveable relative to the host structure through a scaled opening in the horizontal wall  110 . The moveable member  120  comprises a first horizontal member  122  positioned within the chamber  108 , a second horizontal member  124  positioned below the horizontal wall  110 . The first and second horizontal members are connected by at least one support. The first horizontal member  122  divides the chamber  108  into an upper reservoir  132  and a lower reservoir  134 . The first horizontal member  122  includes a first horizontal member valve  126  to allow the fluid to flow from the upper reservoir  132  to the lower reservoir  134  when open, and prevent fluid communication when closed. Since the moveable member  120  is vertically movable, the size of the upper reservoir  132  and the lower reservoir  134  will vary with the vertical movement of the first horizontal member  122 . 
     The vertically moveable first horizontal member  122  which is located within chamber  108  may include a first horizontal member seal therebetween extending around the perimeter of the first horizontal member  122 . The first horizontal member  122  is adapted to prevent the seepage of fluid between the first horizontal member seal and the chamber  108 , while the first horizontal member  122  remains vertically moveable. The first horizontal member seal may be constructed of any suitable material, such that the coefficient of friction between the first horizontal member seal and the chamber  108  is just sufficient to prevent fluid passage between the upper reservoir  132  and the lower reservoir  134  of the chamber but permit an almost unhindered vertical movement of the first horizontal member. 
     An expandable compartment  130  is formed between the at least one side wall of the host structure, the horizontal wall  110  and the second horizontal member  124  of the moveable member  120 . The expandable compartment  130  expands and retracts when the moveable member  120  is vertically moved. 
     An inlet conduit  136  passes through a side wall of the host structure  104  connecting the expandable compartment  130  at a first end and with the main body of fluid at a second end to allow fluid to flow into the expandable compartment  130 . A conduit valve  138  is attached to the inlet conduit  136  to control the flow of the fluid into the expandable compartment  130 . The conduit valve  138  may be placed anywhere within the conduit  136 . To improve control of fluid, a second conduit valve may be positioned at the mouth of the conduit. 
     In order to seal the fluid in the expandable compartment  130 , the horizontal wall  110  which is fixed to the host structure includes a horizontal wall valve  112 . The side wall of the host structure includes at least one side wall opening  118  to allow the fluid to flow from the expandable compartment to the main body of fluid, when open, and to trap fallen fluid in the expandable compartment  130  when closed. The second horizontal member of the moveable member may also include a second horizontal member valve for permitting fluid located in the expandable compartment to flow into the main body of fluid when open, and to trap fallen fluid in the expandable compartment  130  when closed. 
     The vertically moveable second horizontal member  124  located within the host structure may include a second horizontal member seal therebetween extending around the perimeter of the second horizontal member  124 . The second horizontal member  124  is adapted to prevent the seepage of fluid between the second horizontal member seal and the side wall of the host structure, while the second horizontal member  124  remains vertically moveable. The second horizontal member seal may be constructed of any suitable material, such that the coefficient of friction between the second horizontal member seal and the side wall of the host structure is just sufficient to prevent fluid passage from the expandable compartment  130  to the main body of fluid but permit an almost unhindered vertical movement of the second horizontal member. 
     An outlet conduit  150  is in fluid communication with the lower reservoir  134  at a lower end and the upper reservoir  132  at an upper end. The outlet conduit  150  allows fluid to flow from the lower reservoir  134  to the upper reservoir  132 . The outlet conduit  150  may include an outlet conduit valve to control the flow of fluid into the upper reservoir. The outlet conduit  150  may have a tapered or conical shape such that the top end of the outlet conduit is narrower than the bottom end. This may increase the pressure at which the water moves from the lower reservoir to the upper reservoir. 
     An energy extraction device  140  is positioned within the inlet conduit  136  to extract kinetic energy as the fluid flows through the inlet conduit  136  into the expandable compartment  130 . The energy extraction device  140  may be a turbine or device for capturing kinetic energy. The energy extraction device  140  may be placed anywhere within the inlet conduit  136 . 
     The energy extraction device  140  may be connected to a generator  142  for generating electricity. The energy extraction device  140  may also be connected to a device for direct energy consumption. 
     As shown in  FIG. 1 , when the expandable compartment  130  is empty, the moveable member  120  is buoyantly biased to a risen position and the second horizontal member  124  is immersed in the fluid.  FIG. 1  illustrates a first stage of an energy production cycle. The inlet conduit valve  138  is closed which prevents fluid from entering the expandable compartment  130 . The horizontal wall valve  112  is open and the first horizontal member valve  126  and side wall opening  118  is closed. The expandable compartment  130  is empty, the moveable member  120  is buoyantly biased to a risen position and the second horizontal member  124  is immersed in the fluid. By buoyantly biased, it is meant that the moveable member  120  is positively buoyant such that the upward buoyant force on the moveable member  120  is greater than the weight of fluid displaced by the moveable member  120 . The density of the moveable member  120  may be adjusted by utilizing hollow construction of components of the moveable member  120 . 
     The upper reservoir  132  containing fluid applies downward gravitational force on the moveable member  120  to permit the moveable member  120  to be positioned below the surface of the fluid. 
     For example, the downward gravitational force of the moveable member is approximately 16,000,000 N (assuming that the moveable member has 0.02 m thick steel walls, the first horizontal member has a width of 30 m, length of 30 m and height of 1 m, the second horizontal member has a width of 30 m, length of 30 m and height of 5 m, and the support has a width of 0.5 m, length of 75 m and height of 0.5 m). 
     To calculate the depth where the moveable member is neutrally buoyant, assume the surface area of the bottom of the moveable member is 900 m 2  (30 m×30 m), as follows: 
       Pressure=Force/Area 
       Pressure=16,000,000 N/900 m 2    
       Pressure=17.7 kPa 
     Thus, the downward pressure exerted by the bottom wall of the moveable member is 17.7 kPa. 
     To calculate the equilibrium displacement depth of the moveable member when it is neutrally buoyant, it is known that at 100 m depth, the pressure of water is 1000 kPa, as follows: 
       Displacement Depth=(100 m/1000 kPa)*17.7 kPa 
       Displacement Depth=1.77 m 
     Thus, if the gravitational pressure of the bottom wall of the moveable member is 17.7 kPa, the upward buoyant pressure of 17.7 kPa is at 1.77 meters depth from the surface. The moveable member is displaced at a depth of 1.77 m. 
     To calculate the gravitational force required to keep the second horizontal member  124  of the moveable member downwardly displaced at 30 m depth below the surface of the main body of fluid, it is known at that depth, the upward buoyant pressure of water is 300 kPa. Assuming the surface area of the bottom of the moveable member is 900 m 2  (30 m×30 m), the downward gravitational force needed to create 300 kPa is as follows: 
       Force=Pressure×Area
 
       Force=300 kPa×900 m 2  
 
       Force=270,000,000 N 
     Thus, the downward gravitational force required to keep the moveable member displaced at a depth of 30 m is 270,000,000 N. 
     To calculate the mass of 270,000,000 N assume gravity is 9.81 m/s 2 , as follows: 
       Mass=Force/Gravity 
       Mass=270,000,000 N/9.81 m/s 2    
       Mass=27,500,000 kg 
     Thus, the mass required to downwardly displace the moveable member at a depth of 30 meters of fluid is 27,500,000 kg. 
     Since the force required to downwardly displace the moveable member at a depth of 30 meters of fluid is 270,000,000 N and the force of the moveable member is 16,000,000 N, then an additional downward force of 254,000,000 N is necessary. 
     Assuming that the water is used to provide the additional mass to downwardly displace the moveable member at 30 meters, then the mass of water is 26,000,000 kg (254,000,000 N/9.81 m/s 2 ) which is approximately 26,000 meters cubed volume of water (26,000,000 kg/density of water 1000 kg/m 3 ) 
     In a second stage of the energy production cycle, the inlet conduit valve  138  is opened allowing fluid to pass through the horizontal wall valve  112 , and enter the expandable compartment  130 . As fluid flows through the inlet conduit  136 , the energy extraction device  140  captures the kinetic energy of the falling fluid. For example, the moving fluid may spin a turbine. As illustrated in  FIG. 2 , the fallen fluid enters and is trapped in the expandable compartment  130 . The horizontal wall valve  112  remains open and the first horizontal member valve  126  and side wall opening  118  remain closed. As the weight of the moveable member  120  increases due to the fallen fluid, the moveable member  120  will sink deeper in the main body of fluid due to the forces of gravity. As the moveable member sinks to the lowered position, fluid in the lower reservoir  134  flows into the upper reservoir  132  via the outlet conduit  150  which increases the downward force of the moveable member to assist in the downward displacement of the moveable member  120 . The moveable member  120  continues to sink until it reaches the lowered position, as illustrated in  FIG. 3A . 
     For example, the fallen fluid is water having a volume of 27,000 m 3  (30 m*30 m*30 m). To calculate the mass of the fallen water, assume that the density of water is 1000 kg/m 3  and the volume of water is 27,000 m 3 , as follows: 
       Mass=Density×Volume
 
       Mass=1000 kg/m 3 ×27,000 m 3  
 
       Mass=27,000,000 kg 
     The mass of the fallen water is 27,000,000 kg. 
     To calculate the downward gravitational force of the fallen water, assume that gravity is 9.81 m/s 2  and the mass of the fallen water is 27,000,000 kg, as follows: 
       Force=Mass×Gravity
 
       Force=27,000,000 kg×9.81 m/s 2  
 
       Force=270,000,000 N (downward) 
     Thus, the downward gravitational force of the fallen water is 270,000,000 N. 
     The volume of water that flows from the lower reservoir to the upper reservoir as the moveable member sinks to the lowered position is equivalent to the volume of fallen water. To calculate the combined downward gravitational force exerted by the bottom surface of the moveable member at the lowered position, add the gravitational force of each of the moveable member (16,000,000 N), the water in the upper reservoir  132  (254,000,000 N) required to downwardly displace the moveable member at 30 m, the fallen water in the expandable compartment (270,000,000 N) and the water that flows from the lower reservoir to the upper reservoir (270,000,000 N). Thus, a downward force of 810,000,000 N. The pressure exerted by the bottom of the moveable member is as follows: 
     
       
         
           
             
               
                 
                   Pressure 
                   = 
                     
                    
                   
                     Force 
                      
                     
                       / 
                     
                      
                     Area 
                   
                 
               
             
             
               
                 
                   = 
                     
                    
                   
                     810 
                     , 
                     000 
                     , 
                     000 
                      
                     
                       / 
                     
                      
                     900 
                      
                     
                         
                     
                      
                     m 
                      
                     
                         
                     
                      
                     2 
                   
                 
               
             
             
               
                 
                   = 
                     
                    
                   
                     9000 
                     , 
                     000 
                      
                     
                         
                     
                      
                     Pa 
                      
                     
                         
                     
                      
                     or 
                      
                     
                         
                     
                      
                     900 
                      
                     
                         
                     
                      
                     kPa 
                   
                 
               
             
           
         
       
     
     Thus, the moveable member has enough downward force to displace down to a depth of 90 meters which is where the upward buoyant pressure is also 900 kPa. There may be latches, stoppers or other devices to hold the moveable member at 60 meters depth (the lowered position). 
     In a third stage of the energy production cycle, the moveable member  120  reaches the lowered position. As illustrated in  FIG. 3B , once the moveable member  120  sinks to the lowered position, the inlet conduit valve  138  is closed which prevents further fluid from entering the expandable compartment  130 . The horizontal wall valve  112  is closed to trap fluid in the expandable compartment  130  and the side wall opening  118  is opened to permit fluid trapped in the expandable compartment  130  to flow out into the main body of fluid. The first horizontal member valve  126  is opened to permit fluid in the upper reservoir  134  to flow into the lower reservoir  134  which reduces the downward gravitational force of the moveable member  120 . Upward buoyant forces acting on the moveable member  120  assist fluid to flow out of the expandable compartment  130 . The moveable member  120  is pushed upward by the buoyant forces which squeeze the fluid in the expandable compartment  130  between the horizontal wall  110  and the second horizontal member  124 . Thus, the fluid in the expandable compartment  130  flows into the main body of fluid through the side wall opening  118 . The upward buoyant pressure has the capacity to push the moveable member  120  upward to the risen position. 
     The upward buoyant pressure did not have the capacity before to push the moveable member to the risen position because with the side conduit valve and first horizontal member valve closed, the fluid in the expandable compartment and the upper reservoir behaved each as a singular mass bodies with no means for any of the fluid to flow out of their respective encased partitions. With the two valves open, the upward buoyant force will have the capacity to push up just the moveable member; the fluid in the expandable compartment will be forced out into the main body of fluid, and the fluid in upper reservoir will drain into the lower reservoir as the moveable member rises. In the risen position, with the first horizontal member valves closing, the fluid in the upper reservoir will again behave as a single body mass with no means of escape and will have the magnitude to exert enough downward gravitational force on the moveable member, to prevent the buoyant force from pushing higher. 
       FIG. 4  illustrates a fourth stage of the energy production cycle. As the fluid in the expandable compartment  130  flows out, the moveable member  120  rises to the risen position and returns to the first stage. The side wall opening  118 , inlet conduit valve  138 , and first horizontal member valve  126  are closed. The horizontal wall valve  112  is re-opened. The energy producing unit  102  is ready to start another energy production cycle. 
     Controls may be provided to open and close the valves of the present invention. 
     To limit vertical movement of the moveable member  120 , a latch  160  may be provided on the side wall of the host structure. One or more latches  160  are positioned to maintain the second horizontal member  124  immersed in the fluid when the moveable member  120  is in the risen position. A latch may also be useful to limit displacement of the moveable member at the lowered position. 
     Because wind, waves or other forces may hamper vertical movement of the moveable member  120 , a lift may be provided to control vertical movement of the moveable member  120 . A motorized lift may be useful to hold the moveable member  120  in the risen position or to assist the moveable member  120  to vertically move from the lowered position to the risen position. The lift may be useful for maintenance purposes or where unforeseen variables may temporarily hinder the upward movement of the moveable member. The motorized lift may be powered by a power source. 
     The energy producing unit of the present invention may include a counterweight to provide an upward force on the moveable member. A counterweight can be applied to the moveable member to lift the moveable member by either pulling it up or pushing it up. The counterweight derives its upward force using gravity as the source and the direction is converted to an upward direction and applied onto the moveable member. The counterweight&#39;s gravitational pull will be used in conjunction with simple machines such as a pulley, lever, wheel and axel, or any combination of these. The machines may use the counterweight with a mechanical advantage or no mechanical advantage. As well, the counterweight can be used on any hydraulic or pneumatic system, with or without a mechanical advantage, to force the moveable member back up. The counterweight&#39;s upward force is always applied to the moveable member at every stage of the energy creation cycle. 
     A crane may be attached to the moveable member for controlling vertical movement of the moveable member in the risen position. One possible arrangement of a crane  164  is shown in  FIG. 5 . 
     The magnitude of the force created by the counterweight can be used in combination with the upward buoyant force or be large enough to obviate the need for a buoyant force. Any combination in a ratio can be used to offset the downward gravitation force of the moveable member and effectively make the moveable member weightless. Some ratio examples are given: 
     
       
         
           
               
               
               
               
               
             
               
                   
               
               
                 Set up 
                 1 
                 2 
                 3 
                 4 
               
               
                   
               
             
            
               
                 Moveable member  
                 100 N (down) 
                 100 N  
                 100 N  
                 100 N  
               
               
                 gravity 
                   
                 (down) 
                 (down) 
                 (down) 
               
               
                 Buoyant force 
                 100 N (up) 
                 50 N (up) 
                 10 N (up) 
                  0 N 
               
               
                 Counterweight force 
                 0 N 
                 50 N (up) 
                 90 N (up) 
                 100 N (up) 
               
               
                   
               
            
           
         
       
     
     As shown in  FIG. 5 , a chamber wall duct  166  having a chamber wall valve  168  may be positioned in the side wall of the host structure to allow fluid communication between the chamber and the main body of fluid, when open, and to prevent fluid communication when closed. 
     A second horizontal wall  152  having a second horizontal wall valve  154  may be positioned below the expandable compartment  130  to allow the fluid to flow from the expandable compartment to the main body of fluid, when open, and to trap fallen fluid in the expandable compartment  130  when closed. The second horizontal wall  152  is also useful for maintenance or repairs to isolate the main body of fluid from the moveable member and the expandable compartment. 
     Referring to  FIG. 6 , a vertical wall  162  may be positioned in the upper reservoir  132  above the first horizontal member  122 . The vertical wall  162  forms a chamber on top of the moveable member to confine fluid. Thus, fluid may be confined without needing the horizontal member wall to be in contact with the chamber wall as previously shown. 
     A chamber horizontal member  170  having a chamber wall valve  172  may be positioned above the upper reservoir  132  in the chamber  108  to allow the fluid to flow into the upper reservoir, when open, and to prevent communication with the upper reservoir  132  when closed. 
     A side conduit  176  may be positioned outside the chamber in fluid communication with the chamber. The side conduit has at least one side conduit valve  178  to control the flow of fluid between the chamber and the side conduit  176  such that when the side conduit valve  178  is open, allows fluid communication and when closed, prevents fluid communication. 
     The fluid  106  may be water. 
       FIGS. 7 to 10  illustrate two other possible embodiments of the energy producing unit. 
       FIG. 7  shows a cross-sectional view of an energy producing unit  202  according to a second embodiment of the present invention. The energy producing unit  202  has a host structure  204  comprised of at least one sidewall, a bottom wall and a horizontal wall  210 . The host structure  204  is immersed in a fluid  206 . The at least one side wall has openings to permit the fluid to pass through the host structure  204 . A closed chamber  208  comprised of a top wall, a bottom wall and at least one side wall is fixed relative to the host structure  204 . The closed chamber  208  contains chamber fluid  280 . 
     A moveable member  220  is located within the host structure and is independently vertically moveable relative to the host structure. The moveable member  220  comprises a first horizontal member  222  positioned below the horizontal wall  210  and a second horizontal member  224  disposed within the closed chamber  208 . The first and second horizontal members are connected by at least one support. To limit vertical movement of the moveable member  220 , a latch  260  may be provided on the side wall of the host structure. One or more latches  260  are positioned to maintain the moveable member  220  in the risen position. 
     The second horizontal member  224  divides the closed chamber  208  into an upper reservoir  232  and a lower reservoir  234 . The second horizontal member  224  includes a second horizontal member valve  228  to allow the chamber fluid  280  to flow from the upper reservoir  232  to the lower reservoir  234  when open, and prevent fluid communication when closed. 
     The vertically moveable second horizontal member  224  which is located within the closed chamber wall  208  may include a second horizontal member seal therebetween extending around the perimeter of the second horizontal member  224 . The second horizontal member  224  is adapted to prevent the seepage of chamber fluid  280  between the second horizontal member seal and the closed chamber  208 , while the second horizontal member  224  remains vertically moveable. The second horizontal member seal may be constructed of any suitable material, such that the coefficient of friction between the second horizontal member seal and the chamber  208  is just sufficient to prevent chamber fluid  280  passage between the upper reservoir  232  and the lower reservoir  234  of the closed chamber but permit an almost unhindered vertical movement of the second horizontal member. 
     An expandable compartment  230  is formed between the at least one side wall of the host structure, the horizontal wall  210  and the first horizontal member  222  of the moveable member  220 . The expandable compartment  230  expands and retracts when the moveable member  220  is vertically moved. 
     An inlet conduit  236  passes through a side wall of the host structure  204  connecting the expandable compartment  230  at a first end with the main body of fluid at a second end to allow fluid to flow into the expandable compartment  230 . A conduit valve  238  is attached to the inlet conduit  236  to control the flow of the fluid into the expandable compartment  230 . The conduit valve  238  may be placed anywhere within the conduit  236 . To improve control of fluid, a second conduit valve may be positioned at the mouth of the conduit. 
     In order to seal the fluid in the expandable compartment  230 , the horizontal wall  210  which is fixed within the host structure  204  includes a horizontal wall valve  212 . The first horizontal member  222  includes at least one first horizontal member valve  226  to allow the fluid to flow from the expandable compartment to the main body of fluid, when open, and to trap fallen fluid in the expandable compartment  230  when closed. 
     The vertically moveable first horizontal member  222  located within the host structure may include a first horizontal member seal therebetween extending around the perimeter of the first horizontal member  222 . The first horizontal member  222  is adapted to prevent the seepage of fluid between the first horizontal member seal and the side wall of the host structure, while the first horizontal member  222  remains vertically moveable. The first horizontal member seal may be constructed of any suitable material, such that the coefficient of friction between the second horizontal member seal and the side wall of the host structure is just sufficient to prevent fluid passage from the expandable compartment  230  to the main body of fluid but permit an almost unhindered vertical movement of the first horizontal member. 
     An outlet conduit  250  is in fluid communication with the lower reservoir  234  at a lower end and the upper reservoir  232  at an upper end. The outlet conduit  250  allows fluid to flow from the lower reservoir  234  to the upper reservoir  232 . The outlet conduit  250  may include an outlet conduit valve to control the flow of fluid into the upper reservoir. The outlet conduit  250  may be positioned within the host structure as shown in  FIGS. 7 to 10 , or may be disposed on the moveable member and pass through the second horizontal member. The outlet conduit  250  may have a tapered or conical shape such that the top end of the outlet conduit is narrower than the bottom end. This may increase the pressure at which the water moves from the lower reservoir to the upper reservoir. 
     An energy extraction device  240  is positioned within the inlet conduit  236  to extract kinetic energy as the fluid flows through the inlet conduit  236  into the expandable compartment  230 . The energy extraction device  240  may be a turbine or device for capturing kinetic energy. The energy extraction device  240  may be placed anywhere within the inlet conduit  236 . 
     The energy extraction device  240  may be connected to a generator  242  for generating electricity. The energy extraction device  240  may also be connected to a device for direct energy consumption. 
     As shown in  FIG. 7 , when the expandable compartment  230  is fully contracted, the moveable member  220  is buoyantly biased to a risen position and held in the risen position by at least one latch  260 .  FIG. 7  illustrates a first stage of an energy production cycle. The inlet conduit valve  238  is closed which prevents fluid from entering the expandable compartment  230 . The at least one horizontal wall valve  212  is open and the at least one first horizontal member valve  226 , at least one second horizontal member valve  228  and at least one outlet conduit valve  252  are closed. The expandable compartment  230  is fully contracted and the moveable member  220  is buoyantly biased to a risen position. By buoyantly biased, it is meant that the moveable member  220  is positively buoyant such that the upward buoyant force on the moveable member  220  is greater than the weight of fluid displaced by the moveable member  220 . The density of the moveable member  220  may be adjusted by utilizing hollow construction of components of the moveable member  220 . 
     The upper reservoir  232  containing chamber fluid  280  applies downward gravitational force on the second horizontal member  224  to permit the moveable member  220  to be positioned below the surface of the fluid. 
     In a second stage of the energy production cycle, the inlet conduit valve  238  and horizontal wall valve  212  are opened allowing fluid to enter the expandable compartment  230 . As fluid flows through the inlet conduit  236 , the energy extraction device  240  captures the kinetic energy of the falling fluid. For example, the moving fluid may spin a turbine. As illustrated in  FIG. 8 , the fallen fluid enters the expandable compartment  230  through the horizontal wall valve  212  and is trapped in the expandable compartment  230 . The horizontal wall valve  212  remains open and the first horizontal member valve  226  and second horizontal member valve  228  remain closed. The latch  260  is released to permit vertical movement of the moveable member and the outlet conduit valve  252  is opened. As the weight of the moveable member  220  increases due to the fallen fluid, the moveable member  220  will sink in the fluid due to the forces of gravity. As the moveable member sinks to the lowered position, chamber fluid  280  in the lower reservoir  234  flows into the upper reservoir  232  via the outlet conduit  250  which increases the downward force of the moveable member to assist in the downward displacement of the moveable member  220 . The moveable member  220  continues to sink until it reaches the lowered position, as illustrated in  FIG. 9A . 
     In a third stage of the energy production cycle, the moveable member  220  reaches the lowered position. As illustrated in  FIG. 9B , once the moveable member  220  sinks to the lowered position, the inlet conduit valve  238  is closed which prevents further fluid from entering the expandable compartment  230 . The horizontal wall valve  212  is closed to trap fluid in the expandable compartment  230  and the outlet conduit valve  252  is closed to prevent fluid communication between the lower reservoir  234  and the upper reservoir  232 . The first horizontal member valve  226  is opened to permit fluid trapped in the expandable compartment  230  to flow out into the main body of fluid below. The second horizontal valve member  228  is opened to permit chamber fluid in the upper reservoir  232  to flow into the lower reservoir  234  which reduces the downward gravitational force of the moveable member  220 . Upward buoyant forces acting on the moveable member  220  assist fluid to flow out of the expandable compartment  230 . The moveable member  220  is pushed upward by the buoyant forces which squeeze the fluid in the expandable compartment  230  between the horizontal wall  210  and the first horizontal member  222 . Thus, the fluid in the expandable compartment  230  flows into the main body of fluid through the first horizontal member valve  226 . The upward buoyant pressure has the capacity to push the moveable member  220  upward to the risen position. 
     The upward buoyant pressure did not have the capacity before to push the moveable member to the risen position because with the side conduit valve and first horizontal member valve closed, the fluid in the expandable compartment and the upper reservoir behaved each as a singular mass bodies with no means for any of the fluid to flow out of their respective encased partitions. With the two valves open, the upward buoyant force will have the capacity to push up just the moveable member; the fluid in the expandable compartment will be forced out into the main body of fluid, and the fluid in upper reservoir will drain into the lower compartment as the moveable member rises. In the risen position, with the first and second horizontal member valves closing, the fluid in the upper reservoir will again behave as a single body mass with no means of escape and will have the magnitude to exert enough downward gravitational force on the moveable member, to prevent the buoyant force from pushing higher. 
       FIG. 10  illustrates a fourth stage of the energy production cycle. As the fluid in the expandable compartment  230  flows out, the moveable member  220  rises to the risen position and returns to the first stage. The first horizontal member valve, outlet conduit valve and second horizontal member valve are closed. The energy producing unit  202  is ready to start another energy production cycle. 
     Controls may be provided to open and close the valves of the present invention. 
     Because wind, waves or other forces may hamper vertical movement of the moveable member  220 , a motorized lift may be provided to control vertical movement of the moveable member  220 . A motorized lift may be useful to hold the moveable member  220  in the risen position or to assist the moveable member  220  to vertically move from the lowered position to the risen position. The motorized lift may be useful for maintenance purposes or where unforeseen variables may temporarily hinder the upward movement of the moveable member. The motorized lift may be powered by a power source. 
     The energy producing unit of the present invention may include a counterweight may to provide an upward force on the moveable member. A counterweight can be applied to the moveable member to lift the moveable member by either pulling it up or pushing it up. The counterweight derives its upward force using gravity as the source and the direction is converted to an upward direction and applied onto the moveable member. The counterweight&#39;s gravitational pull will be used in conjunction with simple machines such as a pulley, lever, wheel and axel, or any combination of these. The machines may use the counterweight with a mechanical advantage or no mechanical advantage. As well, the counterweight can be used on any hydraulic or pneumatic system, with or without a mechanical advantage, to force the moveable member back up. The counterweight&#39;s upward force is always applied to the moveable member at every stage of the energy creation cycle. One possible arrangement of a pulley counterforce  282  is shown in  FIG. 11 . 
     The magnitude of the force created by the counterweight can be used in combination with the upward buoyant force or be large enough to obviate the need for a buoyant force. Any combination in a ratio can be used to offset the downward gravitation force of the moveable member and effectively make the moveable member weightless. 
     An energy producing structure may be provided comprising two or more energy producing units. The energy producing structure permits continuous energy production by staggering energy production cycles of energy producing units to permit an energy extraction device to continuously extract kinetic energy from falling fluid. As illustrated in  FIG. 12 , a top view of an energy producing structure  300  is shown having two energy producing units  302   a ,  302   b . The energy producing structure  300  permits continuous energy production by staggering energy production cycles of energy producing units  302   a ,  302   b  to permit an energy extraction device  340  to continuously extract kinetic energy from falling fluid  306 . For example, as a first energy producing unit  302   a  rises to a risen position, the other energy producing unit  302   b  sinks to a lowered position. The energy producing structure  300  has two conduits  336   a ,  336   b  in sidewalls of the host structure  304   a ,  304   b , respectively. Two conduit valves  338   a ,  338   b  control the flow of fluid between energy producing units  302   a ,  302   b , respectively. To improve control of fluid, a third conduit valve  344  may be positioned at the mouth of the conduit. A second energy extraction device may be provided such that an energy extraction device is positioned in each of the conduits  336   a ,  336   b.    
     In another example, as soon as the inlet conduit valve is closed in a first energy producing unit which prevents further fluid from entering the expandable compartment, falling fluid could be diverted to a second energy producing unit to provide continuous extraction of kinetic energy. 
     The foregoing description illustrates only certain preferred embodiments of the invention. The invention is not limited to the foregoing examples. That is, persons skilled in the art will appreciate and understand that modifications and variations are, or will be, possible to utilize and carry out the teachings of the invention described herein. Accordingly, all suitable modifications, variations and equivalents may be resorted to, and such modifications, variations and equivalents are intended to fall within the scope of the invention as described and within the scope of the claims.