Buoyancy device

Description

TECHNICAL AREA

[0001] The invention relates to a device for converting kinetic buoyancy energy and / or potential energy into electrical and / or mechanical energy. STATE OF THE ART

[0002] A variety of devices are known in the prior art that are intended to utilize the buoyancy energy of at least one, usually hollow, buoyant body. Such a device is also known as a buoyancy power plant.

[0003] German patent DE 8510493U1 discloses a device in which spherical buoyancy bodies move alternately from a water-filled container to an air-filled container. The spherical buoyancy bodies are connected to each other by a chain. This movement drives wheels connected to a generator. A disadvantage of this device is that losses inevitably occur because the sealing elements cannot prevent water from escaping.

[0004] A similar principle is disclosed in DE2557746A1. Here, buoyancy bodies are arranged on a conveyor belt, which drives a generator via wheels. To enable the buoyancy bodies to enter the water-filled container against the hydrostatic pressure, the device includes a pumping system that pumps water from a water collection tank at increased pressure into a pressurized water chamber. A disadvantage of this is that the pumping system consumes energy, which minimizes the efficiency of the device.

[0005] The DE102016010718A1 , DE9300674U1 , DE202010011168U1 , DE102016009649A1, DE102009037452A1 , DE4029150A1 , DE0022693A1 ,DE2606160A1 describes further, similar devices that follow the same operating principle. All these devices have in common that the buoyancy elements are mechanically coupled to each other via an element (chain, cord, etc.). This results in the frictional / inertial forces of the buoyancy elements located further back on the connecting element (chain, rope, conveyor belt, etc.) being transferred to buoyancy elements located further forward, thus reducing efficiency.

[0006] WO2003058058A1 / DE202004009597U1 discloses a device for utilizing the buoyancy energy of floating bodies. The floating bodies are attached to a rotatably mounted transport device and orbit an upper and lower turning point. The device also includes a lock mechanism in the lower section, which connects two basins with different liquid levels. The floating bodies travel along a chain, but it is unclear how the chain is to be guided through the lock to ensure a sufficient seal. Furthermore, energy is required to operate the locks, which reduces the efficiency of the system.

[0007] German patent DE102017007471A1 discloses a device for generating energy using the buoyancy force in a liquid-filled container, wherein the buoyancy elements are connected to each other by a chain and guided through two locks. Here too, it is unclear how the chains are to be guided through the locks, and the operation of the locks reduces the efficiency of the device.

[0008] US Patent 20150267677A1 describes an apparatus for continuous energy generation that utilizes buoyancy and gravity. This device uses interconnected, gas-filled buoyancy chambers. These chambers enter a liquid-filled space from below through an airlock, where they experience buoyancy. The interconnected nature of the gas-filled buoyancy chambers also results in additional frictional losses, reducing the apparatus's efficiency.

[0009] German patent DE 9404819U1 discloses a gravity motor that uses buoyancy and gravity to generate energy. A piston circulates within a tube system, passing through two airlocks designed to prevent the mixing of the media (air and water). In one embodiment, the piston moves along guide rails, which are interrupted in the airlock area. In addition to actuating the airlocks, energy must also be expended to move pivoting guide elements to close the guide rails in the airlock area. A further disadvantage is that the additional mechanical components, such as the pivoting guide elements, increase the device's susceptibility to mechanical failure.

[0010] German patent DE102014000866A1 discloses a controlled buoyancy system for energy generation in which volume-variable, gas-tight hollow bodies (balloons) are continuously guided through a liquid container by an endless traction element. The balloons are fluidly connected via a hose, so that the gaseous contents of the balloon are forced into the following balloons when a section is passed that compresses the preceding balloon. A disadvantage here, too, is that the buoyancy bodies are interconnected. Furthermore, the buoyancy bodies must be mechanically compressed, which drastically reduces efficiency.

[0011] Devices are also known in which the buoyancy bodies are not mechanically coupled to each other. For example, DE102010015667A1 discloses , DE102013009842A1 , DE102011003099A1 ,DE102010051596A1 Devices in which the buoyancy elements are guided within a pipe or chamber system. A disadvantage of this design, however, is that due to the lack of mechanical coupling, the buoyancy elements must be guided individually through a lock system, which in turn reduces efficiency.

[0012] DE102006007738A1 discloses a method for converting the kinetic energy of materials (buoyancy bodies) into rotational energy for driving generators. Here too, unconnected buoyancy bodies are guided through a lock system, which must be controlled accordingly, thus reducing efficiency.

[0013] KR1020020030848A discloses a device for generating energy using buoyancy and gravity. Unconnected buoyancy bodies are alternately guided through fluids of different densities. The denser, and therefore heavier, fluid is intended to push against the lighter fluid due to its gravity, allowing the latter to have a higher fluid level than the heavier fluid. The buoyancy bodies sinking due to gravity push the leading buoyancy bodies into the heavier fluid and then into the lighter fluid, where they rise due to buoyancy. A disadvantage is that the movement of the buoyancy bodies inevitably leads to mixing of the fluids, which reduces efficiency.

[0014] WO 2014 / 014425 A1 describes a device for converting thermal energy into electrical energy, wherein the device has a liquid storage unit divided into two parts: a first part containing a high-temperature liquid and a second part containing a low-temperature liquid. Buoyancy elements, which change in volume and thus experience different buoyancy depending on the temperature of the first and second parts, drive a structure connected to a generator for electricity production. A disadvantage is that, because the buoyancy elements are not connected to each other, they move randomly through the first and second parts.

[0015] US Patent 5,125,233 A describes an energy conversion device that converts heat into mechanical energy. A fluid is heated or cooled in a first and second line using heating and cooling lines. A multitude of balloons, connected by a continuous belt, are alternately passed through the first and second lines. In the heated line, the fluid inside the balloon evaporates, causing it to rise. Within the second line and in a cooling bath, the gas condenses back into the fluid, and the process begins again. A disadvantage, however, is that heat transfer in both the heating and cooling lines occurs via a gaseous medium (air), which is a poorer conductor of heat than a liquid such as water.

[0016] Prior art documents also exist that propose utilizing capillary rise for generating electrical energy. For example, AT520053A1 and JPS5813172A each describe a system of interconnected basins and capillary tube elements, in which a liquid is to be transported from a lower basin to a higher basin by means of capillary rise. However, both systems suffer from the disadvantage that the capillary flow is interrupted and thus ceases in the upper basin.

[0017] German patent DE10257375A1 describes a system that also utilizes capillary forces, but in this case, the element containing the capillaries is heated to evaporate the water within them. Furthermore, the water is heated before entering the capillaries. A disadvantage of this system is that gas formation occurs within the capillaries, which in turn interrupts the capillary flow. Moreover, it is not described how the energy required for heating and evaporation is supplied. TASK

[0018] It is therefore an object of the present invention to provide a buoyancy energy utilization device that dispenses with a mechanical coupling of the buoyancy bodies and simultaneously with a lock system with movable mechanical elements (e.g., flaps, doors). The device should have a higher efficiency than the buoyancy power plants known from the prior art. Furthermore, it is an object of the present invention to guide buoyancy bodies safely and stably along a desired path of movement. SOLUTION

[0019] The problem is solved by the buoyancy force utilization device according to claim 1. Further advantageous embodiments can be found in the dependent claims, the description, and the exemplary embodiments. GENERAL BENEFITS

[0020] Since the buoyancy bodies according to the invention are not mechanically coupled to each other, frictional / inertial forces occurring in downstream connecting elements and downstream buoyancy bodies cannot be transferred to upstream connecting elements and buoyancy bodies, thereby increasing the efficiency.

[0021] Furthermore, due to the lock system according to the invention, no connecting elements are necessary. This results in fewer components overall, which leads to weight savings and reduced wear.

[0022] The surface of the buoyancy body facing the first medium and / or second medium has a profile, which ensures that the movement of the buoyancy body is safe and stable and prevents rotation of the buoyancy body around its longitudinal axis.

[0023] Further advantages can be found in the description and the examples of implementation. DESCRIPTION OF THE INVENTION

[0024] The invention comprises a buoyancy force utilization device with which kinetic buoyancy energy as well as potential energy are to be utilized.

[0025] Energy is generally understood as the capacity to do work, release heat, or emit light. Energy is required when something is to be set in motion, accelerated, lifted, heated, or illuminated. Mechanical work (W) is the product of force (F) and the distance (s) traveled by the body performing the work.

[0026] According to the invention, kinetic buoyancy energy is understood to be the ability to perform mechanical work by means of the static buoyancy force exerted on a body. Static buoyancy is a force acting on a body in liquids or gases that opposes gravity. Static buoyancy is caused by the displacement of the surrounding medium. The buoyancy force arises because hydrostatic pressure depends on the height of the location in question. A higher pressure acts on the underside of the body than on its upper side. The static buoyancy corresponds to the weight of the corresponding deformation of the fluid. This relationship is known as Archimedes' principle. A body immersed in a fluid with a density (ρ) is thus subjected to a buoyant force (FA). This force is calculated as the product of the volume (V) of fluid displaced by the body, its density (ρ), and the acceleration due to gravity (g).The weight force (FG) of the displaced fluid and the buoyant force (FA) can therefore be calculated using FA / G = g * p * V. This formula shows that the buoyant force is greater the denser the fluid and the larger the volume displaced by the body. However, the weight force of the body opposes the buoyant force, so for maximum buoyancy, a substantially hollow body is preferred, resulting in a body with a lower average density than the fluid.

[0027] Potential energy, or gravitational potential energy, enables work to be done in the direction of gravity. In Earth's gravitational field, potential energy is the energy a body possesses due to its height. A body falling from a height of 20 meters can do twice as much work as a body falling from a height of 10 meters. During the fall, the potential energy is converted into kinetic energy or other forms of energy and decreases. In hydroelectric power plants, the potential energy of the water in a reservoir can be converted into electrical energy.

[0028] According to the invention, the potential energy and / or the kinetic buoyancy energy of a body can be converted into electrical energy and / or mechanical energy. For example, the buoyancy or downward movement of the buoyant body can be used to set another body in motion via a mechanical coupling. Accordingly, the device according to the invention comprises a converter configured to convert the kinetic buoyancy energy into mechanical and / or electrical energy. The converter can be designed as a generator to provide electrical energy. Various embodiments of coupling mechanical elements with generators are known to those skilled in the art.

[0029] According to the invention, a body comprises at least one buoyancy element which is movable in a fluid. A fluid can be a liquid (e.g., water, oil) or a gas (e.g., air, hydrogen, helium).

[0030] In this context, a space is understood to be an area encompassing a medium defined below. A space can be a delimited area (e.g., a container). A space can also be an undelimited area (e.g., a marine or limnic system such as a sea or a lake).

[0031] The device according to the invention comprises at least one first chamber filled with a first medium, wherein the first medium comprises a fluid, and at least one second chamber filled with a second medium, wherein the second medium comprises a fluid. In a preferred embodiment of the invention, the first medium has a higher average density than the second medium, and the second medium has a lower average density than the buoyancy body.

[0032] According to one embodiment of the buoyancy-utilizing device, the device serves to utilize and convert kinetic buoyancy energy and potential energy into mechanical and / or electrical energy, wherein the device comprises as components a first chamber filled with a first medium, a second chamber filled with a second medium, at least one buoyancy body, and a circumferential guide, wherein at least one buoyancy body moves along the circumferential guide, wherein the average density of the first medium is greater than that of the second medium, wherein the circumferential guide extends through the first chamber and the second chamber, wherein the circumferential guide comprises an endless rail system, wherein the first chamber and the second chamber are separated from each other at at least one point by a lock system, wherein the lock system has a permanent opening.the opening of the lock system is precisely designed to fit the smallest lateral cross-section of the buoyancy body.

[0033] In particular, the invention relates to a buoyancy-utilizing device for utilizing and converting kinetic buoyancy energy and / or potential energy into mechanical and / or electrical energy, wherein the device comprises as components a first chamber filled with a first medium, a second chamber filled with a second medium, at least one buoyancy body, and a circumferential guide, wherein at least one buoyancy body moves along the circumferential guide, wherein the circumferential guide extends through the first chamber and the second chamber, wherein the circumferential guide preferably comprises an endless rail system, wherein the first chamber and the second chamber are separated from each other at at least one point by a lock system, wherein the lock system has a permanent opening, and wherein the buoyancy body is configured such thatthat its mean density and buoyancy as described herein depend on a temperature, wherein the temperature of the first medium and the second medium differs, wherein the device is arranged such that an external energy source induces the temperature change in the first and / or second space, wherein the first medium is located in the first space and the second medium is located in the second space.

[0034] In one embodiment, the temperature of the first medium differs from the second medium by at least 5 K, preferably by at least 10 K, particularly preferably by at least 15 K, very preferably by at least 20 K, further preferably by at least 25 K and further particularly preferably by 30 K.

[0035] A temperature change can be achieved by adding or removing heat from the first and / or second space. Preferably, the temperature change is induced by an external energy source. This external energy source can be a device that removes heat energy (e.g., a combustion plant, solar collector). A geothermal process can also be integrated with an energy source.

[0036] In particular, the average density of the first medium can also be lower than the average density of the second medium, with the density being induced by a heat exchanger described below. Thus, the density of the first medium decreases relative to the second medium if the media have the same chemical structure as described below and the heat exchanger causes a temperature change in the first medium but not in the second. Specifically, the temperature change in the first and / or second chamber, due to the design of the buoyancy body, causes a change in the density and buoyancy of the buoyancy body, depending on the chamber in which the buoyancy body is located. The average density and buoyancy of the buoyancy body depend on the chamber through which the buoyancy body moves. This is described in more detail below.

[0037] According to a particularly preferred embodiment, the mean density of the buoyancy body decreases or increases with increasing temperature. Preferably, the mean density of the buoyancy body decreases as described herein.

[0038] In a particularly preferred embodiment, both spaces include a circumferential guide. This guide is understood to be a boundary that restricts the movement of the buoyancy body in two of its three dimensions. Particularly preferred is the movement of the buoyancy body as well as its lateral extension along the continuous rail system being limited by a continuous rail system.

[0039] Essentially, the buoyant body can be moved away from the Earth's center by buoyancy and towards the Earth's center by falling. To allow a change from upward movement to downward movement (i.e., towards the Earth's center) and vice versa, at least two reversal points are necessary, with the invention comprising an upper reversal point and a lower reversal point. According to the invention, the change from an upward movement of the buoyant body to a downward movement of the buoyant body occurs at the upper reversal point. The change from a downward movement to an upward movement of the buoyant body occurs at the lower reversal point.

[0040] According to one embodiment, the continuous rail system comprises a lower reversal point and an upper reversal point. In particular, at least one of the reversal points, preferably the upper reversal point, is designed such that the continuous rail system can be interrupted or opened at this point. This advantageously allows the buoyancy elements to be removed from or inserted into the continuous rail system.

[0041] The orientation of the device can be described within a Cartesian coordinate system. The negative z-axis points towards the Earth's center, and the positive z-axis points away from it. The terms "below" and "above" refer to the spatial position of an object within the Cartesian coordinate system, with a lower position being closer to the Earth's center than an upper position.

[0042] The continuous guide runs through the first and second chambers and comprises an endless rail system designed to guide at least one buoyancy body. The endless rail system can be configured such that at least two parallel guide rails extend parallel to the z-axis through the first and second chambers. At the transitions between the first and second chambers, as well as between the second and first chambers, the guide rails must curve, meaning they are not parallel to the z-axis in these areas. The curvature of the guide rails must be designed to allow the buoyancy body to move with minimal friction. The advantage of using an endless rail system is that the buoyancy body can move continuously through it. Furthermore, the endless rail system is wear-free, as it contains no moving parts.

[0043] In particular, the continuous rail system is designed such that the lateral movement of the buoyancy element along the continuous rail system is limited. This advantageously allows the buoyancy element to move along a defined path through the first and second chambers. The continuous rail system can be designed so that the buoyancy element does not move in a straight line through the first and / or second chamber, but rather, for example, in a wave-like pattern. This advantageously increases the residence time of the buoyancy element in the first and / or second chamber, thereby extending the time during which the buoyancy element absorbs and / or releases heat to or from the first and / or second medium.

[0044] To enable the smoothest possible movement of a buoyancy element within the continuous rail system, the system can incorporate friction-reducing elements. For example, a friction-reducing element can be made of a low-friction plastic such as polytetrafluoroethylene (PTFE). This element contacts the guide rail, advantageously allowing the buoyancy element to glide smoothly through the continuous rail system. Furthermore, the continuous rail system can also include wheel or roller elements, which create a distance between the hollow body and the continuous rail system, thereby reducing friction.

[0045] The first and second chambers can be separated from each other by at least one further third chamber (also: transition area), wherein the third chamber comprises an airlock system. Preferably, the airlock system is arranged at the lower reversal point. In one embodiment of the invention, the opening of the airlock system is precisely shaped to fit the smallest lateral cross-section of the buoyancy body.

[0046] According to a preferred embodiment, the airlock system is arranged at the lower reversal point between the first and second chambers. It can also be arranged at the upper reversal point or at both the upper and lower reversal points. This advantageously ensures that the temperature barrier described below is formed at both the upper and lower reversal points, thus preventing temperature equalization of the medium in the first and second chambers and improving the efficiency of the device.

[0047] According to a preferred embodiment, the buoyancy body moves alternately from the first space to the second space and moves, at least in a transition area between the first space and the second space, through the lock system and in particular through an opening encompassed by the lock system as described herein.

[0048] According to one embodiment, the lock system is designed such that the buoyancy body can be moved continuously through it. This continuous movement advantageously allows for uninterrupted movement of the buoyancy body through the lock system without the use of moving parts such as lock doors.

[0049] In a further embodiment of the invention, the lock system comprises at least one sealing element, which can, for example, be designed as a lip seal. According to the invention, the sealing element is precisely shaped to fit the smallest lateral cross-section of the buoyancy body, so that the latter can be guided through it with a precise fit. In the case of a cylindrical buoyancy body, the smallest lateral cross-section is perpendicular to the cylindrical surface. In the case of a spherical buoyancy body, the smallest lateral cross-section corresponds to the largest diameter (or great circle) of the spherical shape.

[0050] "Precisely fitting" means that the buoyancy body can move freely through the lock and that, advantageously, the buoyancy body does not become jammed inside the lock.

[0051] Several sealing elements can also be connected in series. The person skilled in the art will select the number of sealing elements, their dimensions, and their material in such a way as to allow low-friction movement of the buoyancy bodies through them.

[0052] According to the invention, the continuous rail system is interrupted in the physical sense by at least one sealing element. However, since guide rails are also arranged between the sealing elements and the buoyancy body moves continuously through them, the system will continue to be referred to as a continuous rail system, although the term "discontinuous rail system" would be more appropriate.

[0053] In contrast to systems described in the prior art, the airlock system has a permanent opening, meaning that the first and second chambers are not separated by an airlock system with gates or flaps. A permanent opening and the absence of an airlock system with moving mechanical parts advantageously allow for low-wear operation of the device according to the invention. Furthermore, no energy is required to open or close the airlock.

[0054] For the buoyancy aid to rise within a fluid, its average specific density must be lower than that of the surrounding fluid. The buoyancy aid is preferably designed as a hollow body, the material of which comprises a metal (e.g., aluminum, stainless steel), a preferably thermoplastic polymer such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), glass, an organic material (e.g., wood), or a semi-synthetic plastic. Furthermore, the material of the hollow body can also include glass fiber reinforced plastics (GFRP).

[0055] Preferably, the buoyancy body is designed in such a way that it can easily absorb and release heat energy.

[0056] In one embodiment, the average density of the buoyancy body, and thus its buoyancy, depends on a temperature change. For this purpose, the buoyancy body comprises a temperature-varying medium and / or a technical element whose spatial extent depends on a temperature change. The variability of the spatial extent can influence the volume, the average density, and thus the buoyancy of the buoyancy body. According to the invention, a temperature change is understood to mean a decrease in temperature and, preferably, an increase in temperature.

[0057] The interior of the hollow body can contain a gas and / or a polymer as a temperature-varying medium, the expansion of which influences the average density of the hollow body. For example, a gas can be used that changes its expansion depending on the temperature of the fluid. The hollow body can be designed to be at least partially flexible, so that the expansion of the gas increases the volume of the buoyancy aid and thus increases buoyancy.

[0058] In particular, the average density of the buoyancy body can be influenced by the expansion of the gas and / or the polymer, the expansion of which depends on a temperature change in the first and / or second chamber. This temperature change causes the medium contained in the first or second chamber to become colder or, preferably, warmer. The buoyancy body can therefore absorb heat in the warmer chamber and release it in the colder chamber. A reduced volume of the buoyancy container can reduce the buoyancy, and an increased volume can increase it. It should be understood that the chamber containing the warmer of the two media can also be referred to as the warm chamber.

[0059] In an advantageous embodiment, the buoyant body moves downwards in the warmer space because its volume decreases with heat. Thus, the buoyancy is reduced both by the warmer medium surrounding the buoyant body and by its smaller volume. This results in the downward force of gravity being greater than the buoyant force. Advantageously, this supports the downward movement of the buoyant body. Conversely, the larger volume of the buoyant body in the colder space supports the upward movement.

[0060] A preferred embodiment provides that the buoyancy body expands when heated and performs the upward movement in the warmer space. Preferably, the materials from which the buoyancy body is formed are selected such that the increase in buoyancy due to the larger volume of the buoyancy body outweighs the effect of the reduced buoyancy due to the warmer medium.

[0061] In one embodiment, the buoyancy body is designed as a hollow body with at least one lifting cylinder arranged in its center, encompassing the interior of the hollow body. The lifting cylinder can move back and forth relative to the hollow body in the direction of its longitudinal axis, with this movement being caused by the temperature-dependent expansion of the temperature-varying medium enclosed by the interior. This design of the buoyancy body allows it to move precisely through the airlock system if the opening of the airlock system is precisely matched to the smallest lateral cross-section of the buoyancy body. For example, the hollow body can be cylindrical, with the diameter of the opening of the airlock system corresponding precisely to the outer diameter of the hollow body.This advantageously allows the lifting cylinder to move back and forth without being limited by the dimensions of the lock system's opening. In other words, the lifting cylinder moves parallel to the movement of the buoyancy element through the continuous rail system.

[0062] By precisely designing the opening of the airlock system, it can advantageously be achieved that the airlock system, in conjunction with the buoyancy element, forms a barrier that prevents the media of the first and second chambers from mixing. In particular, this interaction provides a temperature barrier, preventing the temperatures of the media enclosed by the first and second chambers from equalizing. Preferably, the material from which the buoyancy element is at least partially formed comprises a thermally poorly conductive or insulating material (with a thermal conductivity coefficient defined below), such as a plastic or wood as defined herein.

[0063] It goes without saying that if the buoyancy body is to function as an insulating element within the temperature barrier, it must be designed, on the one hand, to prevent heat transfer from the warmer space to the colder space, and on the other hand, to be capable of absorbing or releasing thermal energy within a short period (e.g., within 5 minutes) in order to change its average density as described herein. This can be achieved, for example, by...This can be achieved by designing the buoyancy body in a cylindrical shape, wherein the end faces of the cylinder are made of a thermally poorly conductive material, whereas the outer surface of the cylinder is made of a thermally highly conductive material with a thermal conductivity of at least 20 Wm⁻¹ < K⁻¹, preferably at least 50 Wm⁻¹ < K⁻¹, particularly preferably at least 100 Wm⁻¹ < K⁻¹, and more preferably at least 200 Wm⁻¹ < K⁻¹, and further preferably at least 300 Wm⁻¹ < K⁻¹, and even more preferably at least 400 Wm⁻¹ < K⁻¹. For example, the outer surface of the cylinder can comprise copper as a thermally highly conductive material. The use of copper is particularly advantageous because it is a common and inexpensive metal.

[0064] The temperature barrier thus serves to thermally decouple the first and second chambers from each other, and in particular, to thermally decouple the first and second media from each other. Especially when the first and second media are chemically identical, the airlock system or the temperature barrier can be designed to allow minor leaks, i.e., the transfer of the first to the second or vice versa. It is important to ensure that the leaks are only so large that the efficiency of the device is only negligibly affected or reduced by the transfer of the media, and in particular by heat exchange between the media, so that this preferably results in a temperature change of less than 1 K per hour, more preferably less than 0.5 K per hour, and most preferably less than 0.1 K per hour.The thermal decoupling according to the invention is therefore not to be understood as absolute; rather, the insulation of the first from the second medium achieved by the thermal decoupling depends significantly on the width of the gap between the buoyancy body and the airlock system. Preferably, the area of ​​the gap between the buoyancy body and the airlock system corresponds to a maximum of 5%, more preferably a maximum of 2%, and most preferably a maximum of 1% of the area of ​​the opening of the airlock system. Advantageously, a smaller gap area results in less leakage between the media and better thermal decoupling.

[0065] A transition between the media is further prevented by ensuring that the fill level of the first and second rooms is the same.

[0066] Naturally, the material from which the continuous rail system is formed should, at least in the area around the lock, also comprise a thermally poorly conductive material, preferably with a thermal conductivity coefficient of at most 1 Wm⁻¹ < K⁻¹ < , preferably at most 0.5 Wm⁻¹ < K⁻¹ < , particularly preferably at most 0.01 Wm⁻¹ < K⁻¹ < (e.g. a ceramic, in particular a ceramic coated with a friction-reducing element, or a plastic) in order to prevent heat transfer from the first to the second room or vice versa via the continuous rail system.

[0067] In particular, the description includes a temperature barrier device for thermally decoupling a first space from a second space or for thermally decoupling a first medium from a second medium, wherein the device comprises a lock system and a buoyancy element, the lock system and the buoyancy element being operatively connected in such a way that the passage of the first medium into the second medium or the passage of the second medium into the first medium is prevented. "Prevention" is not considered an absolute term here. The person skilled in the art will preferably select the gap between the buoyancy element and the lock system such that, on the one hand, only a small amount of medium can pass into the other medium and, on the other hand, the movement of the buoyancy element is not significantly affected.The expert must therefore design the temperature barrier device in such a way as to ensure that the buoyancy body glides through the lock system with as little friction as possible and that the media mix as little as possible.

[0068] The description further includes a temperature barrier device for thermally decoupling a first space from a second space or for thermally decoupling a first medium from a second medium, wherein the device comprises a lock system with at least one opening and a buoyancy body, wherein the lock system and the buoyancy body are designed such that the buoyancy body can be passed through the opening of the lock system, wherein at least one sealing element is arranged at the opening of the lock system, which rests against the buoyancy body in such a way, preferably in such a precise fit against the buoyancy body, that a transfer of the first medium into the second medium or a transfer of the second medium into the first medium and / or a temperature exchange between the first and the second medium is prevented.The buoyancy body is preferably designed to be thermally insulating in the direction from the first to the second or in the direction from the second to the first chamber, as described above, thereby preventing heat transfer from the warmer to the colder medium. In a further embodiment, the buoyancy body is designed to be efficient at absorbing heat in addition to thermally insulating the chambers or media from each other.

[0069] The direction from the first to the second room or from the second to the first room refers to the direction of heat transfer from the warmer to the colder medium.

[0070] The opening of the lock system can be designed as described herein, so that the opening fits precisely against the buoyancy body, or the gap can be designed as described above.

[0071] The mixing of media can be particularly well prevented if the airlock system is designed to fit flexibly against the buoyancy body, for example via flexible lips. Furthermore, the airlock system is preferably designed so that the sealing element is also made, at least partially, of a thermally poorly conductive material (e.g., a plastic).

[0072] It is also conceivable that the interior of the hollow body could contain a thermoresponsive polymer as a technical element, which changes its volume depending on the temperature of the fluid. Shape-memory polymers are also conceivable for influencing the volume of the buoyancy body. Shape-memory polymers (e.g., polylactic acid) that return to their original shape under the influence of temperature are known to those skilled in the art. A buoyancy body could, for example, be designed such that a spring element or a pneumatic element is arranged inside it, positioned between two opposing walls, and pushes these walls and a shape-memory polymer element apart to increase the volume of the buoyancy body.A shape-memory polymer element, which contracts under the influence of temperature, can be arranged lengthwise parallel to the spring and counteract the outward force of the spring to reduce the volume of the buoyancy body and thus the specific buoyancy. Alternatively, the interior of the hollow body can be lined with a foamed shape-memory polymer to change the average density of the buoyancy body depending on the temperature.

[0073] In an alternative embodiment, the buoyancy element comprises at least one element made of a shape-memory metal. The material of a shape-memory metal includes, for example, nitinol. A shape-memory metal can, for example, be designed as a spiral and be operatively connected to a spring element or pneumatic element as described above within the buoyancy element, such that the spiral of the shape-memory metal contracts when the buoyancy element is heated, counteracting the force of the spring element or pneumatic element and consequently reducing the volume of the buoyancy element. Advantageously, the use of a shape-memory metal results in less wear on the buoyancy elements.

[0074] It is also conceivable to use embodiments in which at least one element made of a shape memory metal and at least one element made of a shape memory polymer are combined.

[0075] In another embodiment, a polymer network made of a shape-memory polymer surrounds the buoyancy body. The buoyancy body can contain a gas that pushes the walls of the buoyancy body outwards, either depending on or independent of the temperature. The polymer network can contract with increasing temperature, reducing the volume of the buoyancy body and thus its average density. To separate the polymer network from the surrounding fluid, it can be sealed with another flexible layer or enclosed within a shell. This design offers the advantage of allowing the polymer network to be heated or cooled more quickly.

[0076] Shape-memory polymers that change their shape depending on light are also suitable. For example, light-dependent polymers are known from the prior art that are ionized by light exposure, creating an internal osmotic pressure that causes the polymer to swell. As soon as the light exposure ceases, the gel collapses. Particularly in an embodiment utilizing a light-dependent polymer, it is advantageous if the buoyancy body comprises a glass or other transparent material, allowing light to penetrate the outer wall of the buoyancy body and reach the light-dependent polymer behind it.

[0077] Combinations of all the embodiments described above are also conceivable. For example, in one embodiment, the outer polymer network can be combined with a spring element located inside the buoyancy body, and / or a shape-memory metal element and / or a shape-memory polymer element. In further embodiments, shape-memory polymers that expand when the temperature increases can be used.

[0078] To enable a temperature-dependent change in the volume of the buoyancy body, it is necessary that the buoyancy body be exposed to a different temperature in the first chamber than in the second chamber. Depending on the materials used in the buoyancy body, particularly shape-memory metals or shape-memory polymers, a person skilled in the art can determine the necessary temperature difference and provide it, for example, by means of a heat exchanger or heating element. In this respect, the supplied thermal energy can be converted into buoyancy energy and consequently into mechanical and / or electrical energy. In particular, the heat exchanger can utilize the external energy source to provide the amount of heat necessary to heat the first and / or second chamber.

[0079] Since even small temperature differences between the first and second chambers are sufficient for the function of the shape-memory polymer or shape-memory metal described above, the buoyancy-utilizing device can be operated with low heat energy inputs. This has the advantage that temperature changes from processes that exhibit only low heat output can be utilized. For example, it is conceivable that the waste heat from a biological process (e.g., fermentation in a biogas plant) could be directed into at least the first and / or second chamber to effect a temperature change there. Biogas plants are frequently operated in the mesophilic (20–45°C) or thermophilic (>50°C) range. Alternatively, the waste heat from a combustion process can operate the device according to the invention.

[0080] According to one embodiment, the buoyancy body comprises at least one profile designed to engage with the guide rails in order to stabilize the buoyancy body. The profile may include a friction-reducing element as described above.

[0081] According to the invention, the surface of the buoyancy body facing the first and / or second medium comprises a profile. In particular, the surface of the buoyancy body facing the first and / or second medium is designed as a profile that allows the continuous rail system to be guided uninterrupted through the opening of the lock system, thus avoiding the need to interrupt the continuous rail system.

[0082] The shape of the buoyancy body can be essentially cylindrical, elliptical, conical, spherical, pyriform, and / or streamlined, with combinations thereof also being conceivable. Since the buoyancy body moves in at least a first and / or second chamber within a fluid whose average density is greater than that of the buoyancy body, a streamlined shape is preferred. Furthermore, a higher hydrostatic pressure acts on the underside of a buoyancy body than on its upper side, which is the reason for its buoyancy. Therefore, an essentially conical shape is preferred. The exact shape and size of the buoyancy body can be selected by a person skilled in the art depending on the fluids and materials used.

[0083] In one embodiment, the motion of the buoyant body, particularly in the second chamber, is influenced by gravity. This means that in the first chamber, the buoyant body moves upwards against the force of gravity within a fluid contained therein, due to buoyancy. After passing a turning point, the buoyant body enters the second chamber, where the fluid has a lower average density than that of the buoyant body. In the second chamber, the buoyant body can therefore follow the force of gravity (i.e., fall) and perform work along the distance traveled by converting the potential energy into electrical or mechanical energy, as described above.

[0084] In a further embodiment, a buoyancy body comprises at least one magnetic element, wherein at least one coil is arranged around this element along the endless rail system. During both ascent and descent, the buoyancy body thus moves through the coil and can induce an electric current in it, which can be extracted.

[0085] According to a particularly preferred embodiment, the device provides a heat exchanger and / or a heating element to induce a temperature change in at least the first and / or second chamber. Preferably, the heat exchanger causes a temperature change in only one of the chambers, e.g., the first chamber. This temperature change, preferably an increase in temperature, causes an increase in the temperature of the buoyancy body and thereby a decrease in the average density of the buoyancy body, resulting in increased buoyancy compared to an unheated buoyancy body. The heated buoyancy body then rises within the heated chamber until it reaches its upper turning point and enters the second chamber again.In the second chamber, the temperature is preferably lower than in the first chamber, which causes the average density of the buoyant body to change again and it to sink until it reaches the lower turning point, is exposed again to an increased temperature of the first chamber and the process repeats itself.

[0086] The temperature change caused by a heat exchanger or heating element should occur as close as possible to the lower or upper reversal point and / or to the buoyancy body. The positioning and distance of the heat exchanger or heating element from the buoyancy body can be determined by a person skilled in the art. The positioning and distance should be chosen to induce the most efficient possible temperature change in the buoyancy body while simultaneously ensuring that a temperature change in the first or second chamber does not cause, or only minimally causes, a temperature change in the second or first chamber, depending on which chamber contains the heat exchanger. It goes without saying that the first and / or second chamber must contain insulating elements to limit the temperature change to a specific area.

[0087] To induce a temperature change in the first or second chamber, one embodiment of the invention comprises a heat exchanger comprising a primary and a secondary circuit, wherein the two circuits are not fluid-connected. The heat exchanger can be arranged within the first chamber, with the secondary circuit comprising the medium of the first chamber, while the primary circuit of the heat exchanger carries a third medium / fluid, which carries the waste heat from a heat-generating biological process (e.g., fermentation), and / or a physical process (e.g., solar thermal energy), and / or a chemical process (e.g., combustion). In an alternative embodiment, the heat exchanger can also be arranged in the second chamber. Furthermore, it is conceivable that the heat exchanger induces a temperature decrease in the first and / or second chamber by having its primary circuit carry a fluid that is colder than the buoyancy body.

[0088] According to one embodiment, the primary circuit comprises a third medium that has a higher temperature than the first medium of the first chamber, and which is not fluidly comminable with the first medium. The third medium can be a fluid with a boiling point at least twice that of the first or second medium. For example, the third medium can be a liquid salt. The use of a third medium advantageously allows for more effective heating of the first and / or second medium.

[0089] In one embodiment of the invention, a heat exchanger is omitted, with at least one of the chambers being designed such that the first and / or second medium can be exchanged for a medium at a different temperature. For example, instead of a heat exchanger, the first and / or second medium is passed through the first and / or second chamber, preferably the first medium through the first chamber. The first and / or second medium is supplied from outside, i.e., from outside the first and / or second chamber, and is also discharged to the outside. Advantageously, this eliminates the need for a heat exchanger. The first or second medium passed through could, for example, be water from a cooling circuit or water dissipating waste heat.

[0090] In one embodiment, the first medium is heated by geothermal processes and fed into the first chamber to heat the buoyancy elements, while the second medium, which is cooler—preferably at least 20 K cooler, more preferably at least 30 K cooler, and most preferably at least 40 K cooler—than the first medium, is passed through the second chamber to cool the buoyancy elements. In another embodiment, the device is configured such that, after passing through the second chamber, the second medium is fed into a device that serves to heat the second medium, for example, by geothermal processes, and the second medium is then fed into the first chamber, where it transfers the thermal energy to the buoyancy elements.

[0091] In an advantageous embodiment, a heat exchanger also carries a third medium, which is designed as a coolant, to reduce the temperature in the first and / or second chamber. Alternatively, the first and / or second chamber, preferably only one of the two, can be supplied with a coolant so that buoyancy aids located in the chamber are cooled.

[0092] In one embodiment of the invention, the first and second media have the same chemical structure. For example, the first and second spaces can contain water or oil. The buoyancy body can move through both spaces, with the transition zones between the first and second spaces also being fluidically connected. An airlock system can be arranged between the first and second spaces, which prevents or hinders heat diffusion from the first to the second space. The advantage of this is that the buoyancy body is only exposed to a maximum temperature change in the designated space, thus influencing its volume and consequently its buoyancy. In an alternative embodiment, an airlock system can be omitted.

[0093] In another embodiment, the primary circuit, i.e. the third medium, of the heat exchanger carries the waste heat from a solar collector or another waste heat-producing process described above, wherein the temperature of the third medium is variable.

[0094] The description relates to a method for using the buoyancy-utilizing device comprising moving the buoyancy body in a first space by buoyancy, moving the buoyancy body in a second space by gravity, wherein the movement of the buoyancy body takes place along an endless rail system.

[0095] In particular, the description relates to a method for operating a buoyancy-utilizing device and converting thermal energy into electrical and / or mechanical energy, wherein the method provides a first chamber and a second chamber and at least one buoyancy body, a first medium and a second medium, a heat exchanger, a continuous rail system, and a converter configured to convert the kinetic energy of the buoyancy body into electrical energy. The method includes converting the thermal energy introduced into the first and / or second chamber through the heat exchanger into electrical energy. This is achieved by influencing the average density of the buoyancy body through the thermal energy input as described above.

[0096] Furthermore, the description relates to a method for operating a buoyancy-utilizing device and for converting thermal energy into electrical energy, comprising as steps the provision of a first space and a second space and at least one buoyancy body, a first medium and a second medium, a heat exchanger, an endless rail system and a converter configured to convert the kinetic energy of the buoyancy body, caused by its buoyancy, into electrical energy, wherein the movement of the buoyancy body takes place along an endless rail system, wherein a heat energy input into the first and / or second space occurs via the heat exchanger, and wherein the mean density of the buoyancy body is influenced by the heat energy input as described herein.

[0097] Furthermore, the description relates to a method for converting thermal energy into electrical energy and includes providing a buoyancy-utilizing device defined herein, a converter configured to convert kinetic energy of the buoyancy body, in particular from a movement caused by the buoyancy of the buoyancy body, into electrical energy, wherein the movement, in particular the movement guided by the continuous rail system, of the buoyancy body takes place along the continuous rail system, wherein the heat exchanger induces a temperature difference between the first and the second space, wherein the mean density and the buoyancy of the buoyancy body are increased or decreased by the temperature difference, and wherein the buoyancy body performs a movement in the first and second space depending on its mean density, preferably a movement along the continuous rail system.where the motion is converted into electrical energy by the converter.

[0098] Preferably, heat energy is introduced into the first chamber. However, the heat energy can also be introduced into the second chamber instead of the first. Through the heat energy input of at least one of the media, preferably only one of the media, i.e., the first medium or the second medium, and more preferably the first medium, the buoyancy body is heated and consequently changes its average density, as described herein. The buoyancy body moves alternately from the first to the second chamber, the temperature difference between the chambers, and in particular between the media they contain, being at least greater than 5 K, preferably greater than 10 K, particularly preferably greater than 20 K, most preferably greater than 30 K, and further preferably greater than 40 K. A larger temperature difference advantageously results in more efficient cooling or heating of the buoyancy body.

[0099] In one embodiment of the method, the heat energy input into the first and / or second room is provided by geothermal processes and / or solar thermal energy and / or waste heat producing processes, or other processes described herein.

[0100] Further advantages, features and application possibilities of the present invention will also become apparent from the following description of exemplary embodiments and the drawings. EXAMPLES OF EXECUTION

[0101] The present invention is explained in more detail with reference to the following figures and embodiments, without limiting the invention to these.

[0102] In the different figures, parts that are equivalent in function are always provided with the same reference symbols, so that they are usually only described once.

[0103] The Fig. 1A-CFigure 1 shows an embodiment of the buoyancy-utilizing device (1.0) comprising a first chamber (1.1) filled with a first medium (2.1) (here: water) and a second chamber (1.2) filled with a second medium (2.2) (here: air). The device further comprises buoyancy elements (3.0) which are guided within a circumferential guide (4.0) designed as a continuous rail system. The first chamber (1.1) and the second chamber (1.2) are separated from each other by a sluice gate system (1.3), which is arranged at the lower reversal point (1.4). Fig. 1BThe enlarged lock system (1.3) comprises several lip seals (1.5) connected in series, the inner diameter of which is precisely matched to the cross-section of the buoyancy bodies (3.0). The buoyancy bodies (3.0) are made of polyethylene and coated with polytetrafluoroethylene, so that they can be guided through the continuous rail system (4.0) with minimal friction. Converters (not shown) are arranged along the continuous rail system (4.0) to convert the kinetic energy of the buoyancy bodies (3.0) into electrical energy during their ascent in the first chamber (1.1) and their descent in the second chamber (1.2). Fig. 1C shows the view of the in Fig. 1BThe section plane SS is shown. The circumferential guide (4.0) comprises a first guide rail (4.1), a second guide rail (4.2), and a third guide rail (4.3), the guide rails being arranged at an angle of 120° to each other. The inner diameter of the lip seal (1.5) is precisely matched to the cross-section of the buoyancy body (3.0), so that, advantageously, no first medium (2.1) can penetrate between the buoyancy body (3.0) and the lip seal (1.5). The guide rails (4.1, 4.2, 4.3) stabilize the lip seal and, at the same time, ensure the continuous passage of the buoyancy body (3.0) through the circumferential guide (4.0). Alternatively, only two guide rails arranged at an angle of 180° to each other can be used.

[0104] In the Fig. 2A and Fig. 2B and Fig. 2CEach figure shows an embodiment of a buoyancy body (3.0) which essentially has a circular profile in cross-section. The buoyancy body (3.0) is arranged within three guide rails (4.1, 4.2, 4.3) such that the buoyancy body (3.0) is movable only in the longitudinal direction of the guide rails (4.1, 4.2, 4.3). Fig. 2D shows the in Fig. 2B The buoyancy body (3.0) shown with the guide rails (4.1, 4.2, 4.3) is arranged at an angle of 120° to each other. Fig. 2E Figure 1 shows a modified embodiment, wherein the outer surface of the buoyancy body (3.0) is designed such that it has profiles (5.0) into which the guide rails (4.1, 4.2, 4.3) engage. This profile advantageously prevents rotation of the buoyancy body (3.0) about its longitudinal axis.

[0105] The Fig. 3A and Fig. 3BFigure 3 shows another embodiment of a buoyancy body (3.0) whose mean density, and thus its buoyancy, depends on a temperature change. The buoyancy body (3.0) comprises a centrally arranged pneumatic element (3.1) whose function is to move the molded shells (3.2) apart in order to reduce the mean density of the buoyancy body (3.0), thereby increasing its buoyancy. As soon as the buoyancy body (3.0) heats up, a thermoresponsive polymer shell (3.3) encasing the molded shells (3.2) contracts, the forces exerted by the contraction of the thermoresponsive polymer shell (3.3) opposing those of the pneumatic element. A spring may also be arranged within the pneumatic element (3.1). The maximum force of the pneumatic element (3.1) is set such that the force of the thermoresponsive polymer shell (3.3) counteracts that of the pneumatic element.3) has a larger value once a transition temperature is reached. The average density and thus the buoyancy of the buoyancy body (3.0) decreases due to contraction of the thermoresponsive polymer shell (3.3). If the temperature decreases again, the outward force of the pneumatic element (3.1) predominates, and the buoyancy increases again. The thermoresponsive polymer shell (3.3) is additionally surrounded by a fluid-repellent shell (3.4) made of a stretchable plastic. A fully compressed buoyancy body has the lowest buoyancy. A fully decompressed buoyancy body has the highest buoyancy. The . Fig. 3A This shows the decompressed buoyancy body (3.0) and the Fig. 3B shows a compressing buoyancy body (3.0).

[0106] In the Fig. 3C and Fig. 3DFigure 3 shows another embodiment of a buoyancy body (3.0). Here, the buoyancy body (3.0) comprises a gas-filled pneumatic hollow body (3.5) which is encased by a thermoresponsive polymer network (3.6) and a liquid-repellent shell (3.4). The operating principle corresponds to that described above, wherein the Fig. 3C the decompressed buoyancy body (3.0) and the Fig. 3D shows the compressed buoyancy body (3.0).

[0107] The Fig. 4AFigure 1 shows an embodiment of the buoyancy-utilizing device (1.0), wherein buoyancy bodies (3.0) are depicted whose average density varies with temperature as described above. The continuous rail system is not shown here, but is designed such that the compressed buoyancy bodies (3.7) and the decompressed buoyancy bodies (3.8) are movable within the continuous rail system. There is preferably sufficient clearance between the continuous rail system and the buoyancy body to allow both the decompressed and the compressed buoyancy bodies to move within the continuous rail system. Here, the buoyancy-utilizing device (1.0) comprises a first chamber (1.1) and a second chamber (1.2), separated from each other by an insulating partition (1.6), with both chambers containing the same medium (here: water). A heat exchanger (1.7) is arranged in the second chamber (1.2), which carries the waste heat from a biogas plant. The heat exchanger (1.7) causes a temperature increase in the buoyancy bodies (3.0) passing through it, which are designed as described above and reduce their average density. Upon reaching the lower reversal point (1.4), the buoyancy increases again, causing the buoyancy bodies (3.0) to rise. An air space (2.3) is arranged at the upper end of the first chamber (1.1) and the second chamber (1.2). This serves as an insulator to minimize heat transfer from the second chamber (1.2) to the first chamber (1.1). Converters that convert the kinetic energy of the buoyancy bodies into electrical energy are not shown. In the . Fig. 4B is one of Fig. 4AA slightly modified embodiment is shown, in which there is no air space. Instead, the first chamber (1.1) and the second chamber (1.2) are separated from each other by an insulating partition (1.6), which is designed to prevent heat diffusion from the second chamber (1.2) into the first chamber (1.1), for example by designing the partition openings (1.8) such that as little water as possible can diffuse between the insulating partition (1.6) and the buoyancy body (3.0). The partition openings (1.8) are an embodiment of an airlock system according to the invention.

[0108] The relative sizes of the described components are not shown to scale. Furthermore, the embodiments of the invention shown are to be understood as exemplary and not as limiting. The invention can also be implemented in a different manner. REFERENCE MARK LIST

[0109] 1.0 Buoyancy utilization device 1.1 First chamber 1.2 Second chamber 1.3 Airlock system 1.4 Lower reversal point 1.5 Sealing element / Lip seal 1.6 Insulating partition 1.7 Heat exchanger / Heating element 1.8 Partition openings 1.9 Upper reversal point 2.1 First medium 2.2 Second medium 2.3 Air space 3.0 Buoyancy body 3.1 Pneumatic element 3.2 Molded shells 3.3 Thermoresponsive polymer shell 3.4 Liquid-repellent shell 3.5 Pneumatic hollow body 3.6 Thermoresponsive polymer mesh 3.7 Compressed buoyancy body 3.8 Decompressed buoyancy body 4.0 Circumferential guide / Endless rail system 4.1 First guide rail 4.2 Second guide rail 4.3 Third guide rail 5.0 Profiling

Claims

1. Buoyancy force utilisation device (1.0) for utilising and converting kinetic buoyancy energy and / or potential energy into mechanical and / or electrical energy , comprising the following components: a) a first chamber (1.1) filled with a first medium (2.1), b) a second chamber (1.2) filled with a second medium (2.2), c) at least one buoyancy body (3.0), d) a circumferential guide (4.0), wherein at least one buoyancy body (3.0) moves along the circumferential guide (4.0), wherein the circumferential guide (4.0) runs through the first chamber (1.1) and the second chamber (1.2), wherein the first chamber (1.1) and the second chamber (1.2) are separated from each other at at least one point by a sluice system (1.3), wherein the sluice system (1.3) has a permanent opening, wherein the buoyancy body is designed such that its average density and buoyancy depend on a temperature, wherein the temperature of the first medium (2.1) and the second medium (2.2) differs, wherein the device is arranged such that an external energy source induces a temperature difference between the first (1.1) and second (1.2) chamber, characterised in that the circumferential guide (4.0) comprises an endless rail system, wherein the surface of the buoyancy body (3.0) facing the first medium (2.1) and / or second medium (2.2) comprises a profiling (5.0).

2. Device according to claim 1, wherein the buoyancy body (3.0) is designed as a hollow body, wherein the material of the hollow body comprises a metal, a plastic, a glass, or an organic material.

3. Device according to claim 2, wherein the hollow body comprises a gas and / or a polymer, wherein the average density of the buoyancy body (3.0) can be influenced by the expansion of the gas and / or the polymer, wherein the expansion of the gas and / or the polymer is dependent on a temperature change in the first and / or second chamber.

4. Device according to one of claims 1 to 3, wherein a heat exchanger (1.7) and / or a heating element is provided to induce a temperature change at least in the first and / or second chamber.

5. Device according to claim 4, wherein the heat exchanger or the heating element can induce the temperature change in the immediate vicinity of the lower reversal point (1.4) and / or in the immediate vicinity of the upper reversal point (1.9) and / or in the immediate vicinity of the buoyancy body (3.0).

6. Device according to claim 4 or 5, wherein the heat exchanger comprises a primary and a secondary circuit, wherein both circuits are not fluidically connected to each other.

7. Device according to claim 6, wherein a solar collector and / or a waste heat-producing process is operatively connected to the primary circuit in such a way that the temperature of a third medium can be changed.