Background The steam engine, also known as an external combustion engine, is a heat engine for converting heat energy to work. The conversion is performed by a cycle of processes. Heat created externally is transferred to water in a steam generating unit or boiler 505 to create steam. The steam carries energy to an expander 510, also known as an engine, were part of the heat energy is converted to mechanical energy, work. The steam leaves the engine 510 and is condensed back to water rejecting some heat energy. The steam is condensed back to water by a condenser 515. The water can be stored in an above-ground water reservoir and fed back to the boiler by a pump 520. Fig. 5 shows a known closed-cycle steam power plant 500.

Further, storing items underwater is known in the art. In particular, an electric energy storage system has been used to store off-peak electric energy. Such a system stores highly compressed air in storage vessels anchored to the ocean floor. Before the compressed air is stored in the storage vessels, heat is extracted during each compression stage of a multistage compressor and stored in a heat storage tank. As a result, most of the input energy can be recovered when the stored heat is returned in successive stages to the expanding compressed air. In addition, systems including flexible, submergible cells have also been used to store fuel underwater and have employed the hydrostatic pressure existing at a depth underwater for the purpose of expelling the fuel from the cells. The fuel is delivered through fuel lines to a point above the surface of the water.

A need exists, however, for a system and method that stores exhaust steam produced by an engine as water in a flexible underwater container without the use of a compressor, whereby the water can be extracted from the flexible container by employing hydrostatic pressure.

There is also a need for a double walled flexible container for storing one or more items underwater.

Summary Of The Invention An aspect of the present application provides for a flexible container for storing an item underwater. The flexible container includes an inner flexible wall forming a first cavity for storing the item, and an outer flexible wall surrounding the inner flexible wall, the outer flexible wall forming a second cavity between the inner flexible wall and the outer flexible wall for storing the item or another item.

Another aspect of the present application provide for a flexible container for storing at least soft water and another item underwater. The flexible container includes an inner flexible wall forming a first cavity for storing the soft water, an outer flexible wall surrounding the inner flexible wall, the outer flexible wall forming a second cavity between the inner flexible wall and the outer flexible wall for storing the other item, a first inlet coupled to the inner flexible wall, the first inlet operable to allow the soft water to enter the first cavity, a second inlet coupled to the outer flexible wall, the second inlet operable to allow the other item to enter the second cavity, a first outlet coupled to the inner flexible wall, the first outlet operable to allow the soft water to exit the first cavity, and a second outlet coupled to the outer

flexible wall, the second outlet operable to allow the other item to exit the second cavity, wherein at least the soft water is extracted from the first cavity by employing hydrostatic pressure.

A further aspect of the present application provides for a flexible container for storing at least soft water and another item underwater. The flexible container including an inner flexible wall forming a first cavity for storing the soft water, an outer flexible wall surrounding the inner flexible wall, the outer flexible wall forming a second cavity between the inner flexible wall and the outer flexible wall for storing the other item, a first valve coupled to the inner flexible wall, the first valve operable to allow the soft water to enter the first cavity and to exit the first cavity, and a second valve coupled to the outer flexible wall, the second inlet operable to allow the other item to enter the second cavity and to exit the second cavity, wherein at least the soft water is extracted from the first cavity by employing hydrostatic pressure.

A still further aspect of the present application provides for a flexible container for storing at least two items underwater. The flexible container includes an inner flexible wall forming a first cavity for

storing the at least two items, and an outer flexible wall surrounding the inner flexible wall, the outer flexible wall forming a second cavity between the inner flexible wall and the outer flexible wall for storing at least one of the at least two items or at least one other item.

An aspect of the present application provides for a power generating system, including a boiler for generating steam, an engine coupled to the boiler for using the generated steam, the engine producing exhaust steam, a pipe coupled to the engine, the pipe being operable to convert the exhaust steam to water as the exhaust steam travels underwater through the pipe, and an underwater flexible container coupled to the pipe for storing the water.

Another aspect of the present application provides for a power generating system. The system includes a boiler for generating steam, an engine coupled to the boiler for using the generated steam, the engine producing exhaust steam, a first pipe coupled to the engine, the first pipe being operable to convert the exhaust steam to water as the exhaust steam travels underwater through the first pipe, an underwater flexible container coupled to the first pipe for storing the water, the underwater flexible container including a

cavity for storing the water, and at least one valve operable to allow the water to enter the cavity and operable to allow the water to exit the cavity, and a second pipe coupling the flexible container to the boiler, the second pipe providing the boiler with the stored'water, wherein the stored water is extracted from the flexible container by employing hydrostatic pressure.

A further aspect of the present application provides for a power generating system, including a boiler for generating steam, an engine coupled to the boiler for using the generated steam, the engine producing exhaust steam, a first pipe coupled to the engine, the first pipe being operable to convert the exhaust steam to water as the exhaust steam travels underwater through the first pipe, an underwater flexible container coupled to the first pipe for storing the water, the underwater flexible container including an inner flexible wall forming a first cavity for storing the water, an outer flexible wall surrounding the inner flexible wall, the outer flexible wall forming a second cavity between the inner flexible wall and the outer flexible wall for storing another item, a first valve coupled to the inner flexible wall, the first valve operable to allow the water to enter the first

cavity and to exit the first cavity, and a second valve coupled to the outer flexible wall, the second inlet operable to allow the other item to enter the second cavity and to exit the second cavity, and a second pipe coupling the flexible container to the boiler, the second pipe providing the boiler with the stored water via the second valve, wherein the stored water is extracted from the first cavity of the flexible container by employing hydrostatic pressure.

A still further aspect of the present application provides for a method for storing treated water in a flexible container underwater. The method includes capturing steam, feeding the captured steam through at least one pipe located underwater, the captured steam converting to the treated water as the captured steam travels though the at least one pipe, and storing the treated water in the flexible container coupled to the at least one pipe.

An additional aspect of the present application provides for a method for insulating treated water while stored underwater in a flexible container. The method includes storing the treated water in an inner cavity of the flexible container located underwater, the flexible container also including an outer cavity surrounding the inner cavity, and filling the outer cavity with an

insulator, the insulator operable to keep the treated water at a temperature higher than a temperature of water surrounding the flexible container.

An aspect of the present application provides for a method for insulating treated water while stored underwater in a flexible container, the method including constructing an outer cavity of the flexible container from at least an insulator, submerging the flexible container underwater, the flexible container also including an inner cavity surrounded by the outer cavity, and storing the treated water in the inner cavity of the flexible container, wherein the insulator is operable to keep the treated water at a temperature higher than a temperature of water surrounding the flexible container.

A further aspect of the present application provides for a hydroelectric system. The system includes a hydroelectric power plant including a turbine for generating power, a flexible container secured underwater, the flexible container including at least an upper portion for storing air and a lower portion for storing water, a first pipe coupling the hydroelectric power plant to the upper portion, the first pipe providing air to and removing air from the upper portion, and a second pipe coupling the hydroelectric

power plant to the lower portion, the second pipe providing water to and removing water from the lower portion, wherein at least the water removed from the lower portion causes the turbine to generate power.

A further aspect of the present application provides for a method for powering a turbine using an underwater flexible container having an upper portion and a lower portion, the method including (a) filling the upper portion with air, the upper portion and a weighted platform located between the upper portion and the lower portion rising as the upper portion is filled with air, thereby suctioning water into the lower portion through a pipe coupled to the turbine, (b) removing air from the upper portion, the upper portion and the weighted platform located collapsing on the lower portion causing the water to exit the lower portion through the pipe coupled to the turbine, and (c) repeating (a) and (b), wherein the water powers the turbine.

Brief Description of the Drawings Fig. 1 illustrates an exemplary system including an underwater flexible storage container of the present application; Fig. 2a illustrates an exemplary underwater flexible storage container of the present application;

Fig. 2b illustrates another exemplary underwater flexible storage container of the present application; Fig. 3a illustrates an exemplary system including several underwater storage containers of the present application; Fig. 3b illustrates exemplary components utilizing the underwater storage containers shown in Fig. 3a; Fig. 4 illustrates a further exemplary underwater flexible container; and Fig. 5 shows a known closed-cycle steam power plant.

Detailed Description Figure 1 illustrates an exemplary power generating system 100 of the present application. Power generating system 100 includes boiler 110 and engine 115 coupled to boiler 110. In an exemplary embodiment, boiler 110 is a steam boiler for generating steam and engine 115 is a turbine powered by the generated steam. Boiler 110 and engine 115, however, are not limited to a steam boiler and a turbine. Rather, other power sources, including other types of steam generating units, can be used in place of boiler 110. For example, hot water boilers can be included in power generating system 100. In boiler 110, water is heated to the saturated liquid state,

vaporized to the saturated vapor state, and superheated to produce steam.

As can be seen in Fig. 1, power generating system 100 also includes underwater flexible container 185, described below in more detail with reference to Fig.

2a. Flexible container 185 can be anchored to floor 145, for example, an ocean floor, by anchoring system 140 and connected to buoy 120 by cable 130. Inlet 180 is coupled to engine 115 by pipe 150 and outlet 165 of flexible container 185 is coupled to boiler 110 by pipe 160. Many items, such as steam, water, gas, compressed air or oil, can be stored in flexible container 185.

These items travel to flexible container 185 through pipe 150 to be stored therein and are extracted from flexible container 185 via pipe 160. Pipe 150 and pipe 160 can be flexible or rigid, can be constructed of various materials that are appropriate for residing below water level 125 and are not limited to any particular diameter. In an exemplary embodiment, pipe 150 has a spiral configuration along at least a portion of the distance between engine 115 and flexible container 185, as shown in Fig. 1. More or less spirals can be included in pipe 150 to achieve a desired result such as cooling. Pipe 150 and pipe 160 can also have other configurations. The length of pipe used for pipe

150, the diameter of pipe 150 and the material of pipe 150 contribute to converting the exhaust steam from engine 115 to soft water 170 as the exhaust steam travels down pipe 150 to flexible container 185.

Figure 2a depicts the exemplary underwater flexible container 185 shown in Fig. 1 having soft water 170 stored therein. Soft water 170 is water at least devoid of impurities such as oxygen and silica. The flexible containers shown in the drawings of the present application are merely exemplary and, therefore, are not meant to limit the flexible containers to any particular shapes or sizes. Further, more than one item can be stored in flexible container 185, besides soft water 170. For example, any combination of water, oil, gas, compressed air or other item can be stored in flexible container 185. If contamination is a concern, a membrane, not shown in the drawings, could be used within flexible container 185 to separate the two items during storage. In addition, the densities of the items should be considered if one item is located on top of the other item within flexible container 185, for example, so that the denser item is placed on top of the less dense item.

Flexible container 185 includes wall 135, air pocket 175, inlet 180, outlet 165 and cavity 195 for

storing soft water 170. Wall 135 can be comprised of a woven fabric, such as polyester, nylon or Kevlar. The woven fabric can be coated with neoprene, PVC, urethane, Teflon and/or natural rubber. Other fabrics and coatings can obviously be used, as well materials other than coated woven fabrics, for example, rubber. Soft water 170 enters cavity 195 through pipe 150 and inlet 180. Soft water 170 is extracted from cavity 195 through pipe 160 and outlet 165, as described below.

More or less pipes can be used to fill and to empty cavity 195, and can be attached to flexible container 185 in a variety of locations. In an exemplary embodiment, inlet 180 and outlet 165 are remotely controlled, for example, by sonar. Outlet 165 or a component coupled thereto, not shown in the drawings, can receive a transmitted signal causing outlet 165 to open and, thus, allow soft water 170 to be extracted from cavity 195 using at least the hydrostatic pressure below water level 125. In an alternative embodiment, a multiple-way valve can be used in place of or in conjunction with an inlet and an outlet. Such a valve would be operable to allow an item to travel in a particular direction and along one path out of a plurality of paths and could also be remotely controllable.

Air pocket 175 may not exist if flexible container 185 is completely filled with soft water 170. On the other hand, air pocket 175 will exist, as shown in Figs.

1,2a and 2b, if flexible container 185 is not completely filled, less than all of soft water 170 is extracted from flexible container 185 or air entered cavity 195 when soft water 170 entered cavity 195. The air in air pocket 175 can be bled out of cavity 195, for example, through a valve, not shown in the drawings.

In an exemplary embodiment, boiler 110 is a steam boiler and power generating system 100 shown in Fig. 1 is utilized to capture exhaust steam from engine 115.

The exhaust steam is stored in flexible container 185 in a liquid state, more particularly, as soft water 170, for later use by boiler 110. Engine 110 can be a turbine or any other type of engine powered at least by steam. The manner of generating steam by a boiler, such as boiler 110, is well known in the art and is, therefore, not explained in the present application, as is an engine's use of the generated steam.

Boiler 110 is fed water from a water treatment unit, not shown in the drawings. The water treatment unit treats water, referred to herein as raw water. Raw water contains numerous impurities including algae, calcium, carbon dioxide, chloride, free acids, hardness,

magnesium, oxygen, silica and solids. These impurities, such as oxygen and silica, manifest as corrosion and scale, respectively. As a result, the raw water is treated by the water treatment unit before feeding the water to boiler 110. The treated water is referred to herein as soft water 170 and can be quite expensive and time consuming to produce. Boiler 110 uses soft water 170 to generate steam. The generated steam is fed to engine 115 which in turn uses the steam to perform a task or series of tasks. Exhaust steam, however, is an unavoidable byproduct of engine 115.

The exhaust steam from engine 115 is captured by an exhaust pipe and fed into pipe 150. The exhaust steam enters pipe 150 at a specific atmosphere (atm), whereby one atmosphere is defined to be the average pressure of the earth's atmosphere at water level. By the time the exhaust steam reaches inlet 180 of flexible container 185, the exhaust steam is converted back to soft water 170 and stored in cavity 195 of flexible container 185.

Specifically, as a result of the temperature differential between the water surrounding pipe 150 and the steam in pipe 150, the exhaust steam is converted back to soft water 170 before soft water 170 reaches inlet 180. The length of pipe 150 extends to such a depth that soft water 170 can be extracted from flexible

container 185 by employing the hydrostatic pressure below water level 125 as described below in more detail.

As a result, a condenser coupled to engine 115 is not needed for converting the exhaust steam from engine 115 back to water before piping the water down to flexible container 185 and a pump is not needed for extracting soft water 170 from flexible container 185, even though a pump can be used to supplement the pressure.

The hydrostatic pressure below water level 125 is used to extract soft water 170 from flexible container 185 and to cause soft water 170 to travel to boiler 110 via pipe 160 upon outlet 165 receiving a signal causing outlet 165 to open. As a result of using hydrostatic pressure, soft water 170 can be extracted without the use of a pump or other device for lifting soft water 170 to a point above water level 125. Specifically, since soft water 170 has a gravity less than the gravity of the water surrounding the immersed flexible container 185, a hydrostatic head is formed and is utilized to forcibly expel soft water 170 to a point above water level 125. During emptying of flexible container 185, soft water 170 is forced upwardly from flexible container 185 and the lower portion of flexible container 185 being under greater pressure gradually collapses by the hydrostatic head. The stored and

extracted soft water 170 is used by boiler 110 to again produce steam.

In an alternative embodiment, steam produced by boiler 110, such as during off-peak hours, can be stored in flexible container 185 as soft water 170 to be later used by boiler 110. For instance, engine 115 may only produce steam during off-peak hours at 10 percent of the capacity during on-peak hours. All of the steam or a portion of the steam can be stored in flexible container 185 so that, for example, if a demand for steam during' on-peak hours is great and additional soft water is needed to create steam, stored soft water 170 can be used by boiler 110 as desired.

By using at least one flexible container 185 for storing one or more items underwater, surface storage units are eliminated or reduced. In addition, flexible container 185 is easier to protect from fire, explosions and terrorist acts. In the present application, a condenser unit is also not needed for converting the exhaust steam to soft water, as the traveling distance via pipe 150 and the temperature differential causes the conversion before the steam reaches inlet 180. When it is desirable to extract the item, for example, soft water 170, from flexible container 185, the hydrostatic pressure pushes the item above water level 125 when

outlet 165 is opened. A pump can obviously be used to raise the item to even a greater height.

Figure 2b illustrates another exemplary flexible container 250 that could be used, for example, with power generating system 100 shown in Fig. 1. Flexible container 250 includes outer flexible wall 255, inner flexible wall 265, inlets 285,290, outlets 275,280, inner cavity 270 and outer cavity 260. Outer cavity 260 is formed between outer flexible wall 255 and inner flexible wall 265 and inner cavity 270 is formed by inner flexible wall 265. An item enters outer cavity 260 through pipe 294 and inlet 285 and exits through pipe 298 via outlet 275. An item, such as soft water 170, enters inner cavity 270 through pipe 292 and inlet 290 and exits inner cavity 270 through pipe 296 and outlet 280. Outer flexible wall 255 and inner flexible wall 265 can be comprised of various materials as described above with reference to Fig. 1. Inlets 285, 290 and outlets 275,280 can be, for example, a valve remotely controlled by sonar, whereby the respective valve, or a component coupled thereto, can receive a transmitted signal either causing the valve to open or close. In an alternative embodiment, multiple-way valves can be used in place of or in conjunction with inlets 285,290 and outlets 275,280. Such valves are

operable to allow items to travel in a particular direction and along one path out of a plurality of paths and could also be remotely controllable.

In an exemplary embodiment of the present application, inner cavity 270 stores soft water 170 and outer cavity 260 is used as an insulator. Specifically, outer cavity 260 can insulate soft water 170 stored in inner cavity 270 from the water temperature surrounding flexible container 250 by filling cavity 270 with a material, either in the liquid, solid or gas state, that acts as an insulator before or after flexible container 250 is secured to a floor below water level. As a result, the temperature of soft water 170 is higher than a temperature of the surrounding water. Ideally, soft water 170 will be stored hot or at least warm while stored in inner cavity 270. For instance, outer cavity 260 functions as an insulator when filled with compressed air. As will be appreciated by a person of ordinary skill in the art, other combinations of items or a single item can be stored in cavities 260,270.

Figures 3a and 3b illustrate an additional exemplary power generating system 300 of the present application having two flexible containers 395a, 395b.

Flexible containers 395a, 395b are the same as flexible

container 250 described above with reference to Fig. 2b and like numerals and parts are not again described.

Power generating system 300 includes water treatment plant 360, steam boiler 370, steam boiler 365, turbine 375, turbine 380, gas source 385 and oil source 390, as shown in Fig. 3b. Power generating system 300 also includes two flexible containers 395a, 395b for storing the same or different items. Flexible containers 395a, 395b are secured to floor 330 below water level 335 by anchoring system 140, described below. Buoy 340 is attached to flexible containers 395a, 395b by cable 315. In an exemplary embodiment, flexible container 395a stores soft water from turbine 380 in inner cavity 270 via pipe 320f and inlet 290, and stores gas from gas source 385 in outer cavity 260 via pipe 320e and inlet 285. Flexible container 395b stores soft water from turbine 375 in inner cavity 270 via pipe 320b and inlet 290, and stores oil from oil source 390 in outer cavity 260 via pipe 320a and inlet 285.

The type of boiler and engine and the items stored in the respective cavities of the flexible containers are meant to be merely illustrative. More or less flexible containers can also be used in power generating system 300 and combinations of flexible containers shown in Figs. 2a and 2b can be included in system 300.

Outlet 280 of flexible container 395a is operable to provide soft water to steam boiler 365 via pipe 320g and outlet 275 is operable to provide gas to steam boiler 365 via pipe 320h. Further, outlet 280 of flexible container 395b is operable to provide soft water to steam boiler 370 via pipe 320c and outlet 275 is operable to provide oil to steam boiler 370 via pipe 320d.

As can be seen in Fig. 3b, pipes 320b, 320f carry exhaust steam and soft water from turbines 375,380 to, for example, flexible containers 395b, 305a, respectively. In addition, pipes 320c, 320g carry the stored soft water from flexible containers 395b, 395a to steam boilers 365,370, respectively, to be used by steam boilers 370,365 to generate steam. Pipe 320e can be coupled from gas source 385 to, for example, flexible container 395a so that gas can be stored in flexible container 395a and later used by steam boiler 365 via pipe 320h. The gas can be used to power steam boiler 365. Further, pipe 320a can be coupled from oil source 390 to, for example, flexible container 395b so that oil can be stored in flexible container 395b and later used by steam boiler 370 via pipe 320d. The oil can be used to power steam boiler 370. The energy stored in the gas

and oil is used to boil water in boilers 365,370 and generate steam under pressure.

In operation, water treatment unit 360 supplies water devoid of at least oxygen and silica, referred to in the present application as soft water, to steam boilers 365,370, as shown in, Fig. 3b. Using the soft water, steam boilers 365,370 generate steam. Steam boiler 365 and steam boiler 370 are powered by, for example, gas and oil, respectively. The gas and oil are stored in and extracted from flexible container 395b and flexible container 395a, respectively, in the same manner as storing and extracting soft water as described above with reference to Fig. 1. The generated steam is provided to turbine 375 and turbine 380 which in turn use the steam to perform a task or series of tasks.

Exhaust steam, however, is an unavoidable byproduct of turbine 375 and turbine 380 using the steam. The exhaust steam is captured by exhaust pipes and fed into pipes 320b and 320f, respectively. As described above with reference to Fig. 1, the exhaust steam changes to soft water as the steam travels down to flexible containers 395a, 395b through the respective pipes.

Anchoring system 140 secures at least one flexible container to a floor below water level, such as floor 145. Any system or method for anchoring underwater one

or more flexible containers to a floor or manmade structure can be used with the exemplary embodiments of the present application. For example, chains, cables and/or ropes can be used. As will be appreciated by a person having ordinary skill in the art, the manner chosen to secure at least one flexible container to an underwater floor or manmade structure should take into account the conditions the anchoring system will have to function in, for example, corrosion, currents, temperature and living organisms.

Further, the flexible containers described in the present application can be used to store rain water that collects, for example, in a pool on land. The rain water can be stored in the respective flexible container after pumping the water out of the pool with a pumping device and transporting the rain water through a pipe to the flexible container. The rain water can be extracted from the flexible container as described above with reference to soft water.

In alternative embodiments of the present application, one or more pipes can be coupled to a flexible container having a single wall or multiple walls, whereby the pipe (s) allow a floating vessel to fill the flexible container with an item (s) and/or remove the item (s) from the flexible container.

Figure 4 depicts a still further exemplary underwater flexible container 425 coupled to hydroelectric power station 405. Flexible container 425 includes upper portion 430, lower portion 435 and platform 470 separating upper portion 430 and lower portion 435. Flexible container 425 can be secured to a floor and/or manmade structures, such as a platform, cement blocks and iron blocks. In Fig. 4, flexible container 425 is secured to floor 410 and manmade structures 450a, 450b of anchoring system 445. As described above, any system or method for anchoring underwater one or more flexible containers to a floor or manmade structure can be used with the exemplary embodiments of the present application. For example, line 455 of anchoring system 445 can be made of one or more chains, cables and/or ropes. Buoys 460a, 460b are also connected to manmade structures 450a, 450b by lines 465a, 465b, respectively. Flexible container 425 is coupled to hydroelectric power station 405 by pipe 420 and pipe 415. Pipe 420 supplies air to and removes air from upper portion 430, and pipe, 415 supplies water to and removes water from lower portion 435.

By using flexible container 425 with hydroelectric power station 405, a turbine, not shown in Fig. 4 can be powered. Specifically, when lower portion 435 is filled

with water and upper portion 430 is empty, the weight of platform 470 causes the water in lower portion 435 to be pushed through pipe 415. Once the water reached power station 405, the water can be used to power the turbine.

After the water has been removed from lower portion 435, air is supplied from power station 405 to upper portion 430 via pipe 420. As upper portion 430 is filled with air, upper portion 430 and platform 470 rise causing a vacuum effect to occur in lower portion 435.

Accordingly, water is again supplied to lower portion 435 via pipe 425. Thereafter, the air in upper portion 430 is removed through pipe 420. Thus, a turbine can be powered by simply cycling water and air in and out of lower portion 435 and upper portion 430, respectively.

The embodiments described above are illustrative examples of the present invention and it should not be construed that the present invention is limited to these particular embodiments. Various changes and modifications may be effected by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.