Fluid power plant

Abstract

A flow power plant (1) for installation in flowing waters, comprising a housing (2) having an inlet opening (3) and an outlet opening (4), wherein a turbine (5) connected to a generator (6) is arranged between the inlet opening (3) and the outlet opening (4), and an inlet guard (7) arranged upstream of the inlet opening (3), which has a holding device (8) connected to the housing (2) and protective elements (9) attached thereto, which are rods (9a) oriented downstream at an acute angle (α) to a longitudinal axis (A) of the housing (2), with a fastening end (10) stably mounted on the holding device (8) and a free end (11) arranged outside the housing (2), wherein a distance (D1) from the fastening end (10) to the free end (11) is greater than a distance (D2) from the fastening end (10) to an outer edge (12) surrounding the inlet opening (3). Housing (2),wherein the rods (9a) are arranged at an angle (α) between 30° and 80° to the longitudinal axis (A) of the housing (2) and the housing (2) has a diffuser (14) between the inlet opening (3) and the outlet opening (4).

Description

[0001] The invention relates to a flow power plant for installation in flowing waters, comprising a housing which has an inlet opening and an outlet opening downstream of the inlet opening, wherein a turbine is arranged in the housing between the inlet opening and the outlet opening, which is connected to a generator, and with an inlet guard arranged upstream of the inlet opening, which has a holding device connected to the housing and protective elements attached to the holding device, wherein the protective elements are rods oriented downstream at an acute angle to a longitudinal axis of the housing, with a fastening end stably mounted on the holding device and a free end arranged outside the housing, wherein a distance from the fastening end to the free end is greater than a distance from the fastening end to an outer edge of the housing surrounding the inlet opening.

[0002] Run-of-river power plants utilize the flow of water to generate electricity. For this purpose, the power plants are placed in the flowing water, for example, a river, and anchored in the riverbed. The flowing water drives a turbine within the power plant and an associated electric generator, which produces electricity. The generated electricity can be transmitted via power lines to a location outside the water.

[0003] To protect the turbine and generator from debris carried by the water, an inlet guard is known to be provided, which prevents the debris from entering the hydroelectric power plant. The inlet guard is generally formed by grids or bars connected to a housing of the hydroelectric power plant.

[0004] EP 1 747 373 B1 discloses a device for generating electrical energy in free-flowing waters. An inlet screen extends from a vertically positioned float on the upstream side of the device to the lateral inlet edges of a housing of the device. The inlet screen is composed of V-shaped profiles that extend horizontally one above the other from the float to the inlet edges.

[0005] EP 3 312 412 B1 relates to a free-flow turbine with a tubular turbine casing, which has an inlet opening bounded by an inlet edge. Upstream of the inlet opening, a guide vane assembly is provided, consisting of several guide vanes. The leading edges of the guide vanes extend essentially along a conical surface from a tip to the inlet edge in order to deflect debris over the guide vanes.

[0006] CH 684430 A5 relates to an arrangement with a water turbine for generating electrical energy. The turbine is housed in a casing with a water inlet and an outlet. To protect against stones and debris, the water inlet is covered by a grid. The grid can be located in a plane perpendicular to the turbine's axis of rotation or, to deflect rolling debris, have a conical shape and consist of horizontally arranged bars.

[0007] DE 10 2008 054 361 A1 discloses an energy generation unit standing on the bottom of a body of water or floating in the water, comprising an inlet housing upstream of which a collection device is arranged to prevent the ingress of foreign objects. The collection device can be a rake or consist of pyramidally arranged struts attached to the inlet housing.

[0008] EP 4 123 159 A1 discloses a flow power plant comprising a flow generator and a screen device. The screen device is arranged upstream of a flow inlet of the flow generator and protects the flow generator from solid foreign bodies. The screen device can have several grid elements extending along the flow direction from a first body to a second body. In particular, the several grid elements can each be attached at a first end to the first body and at a second end to the second body. Together with the first and second bodies, the grid elements can surround a cavity.

[0009] AT 527327 B1 discloses a free-flow turbine system with a flow-through casing having an inlet opening and an outlet opening. Turbine impellers connected to a generator are arranged within the flow-through casing. Upstream of the flow-through casing, a support with a main arm is provided and is rigidly connected to the casing. Several deflector bars of a screen are attached along the main arm and on both sides thereof. These deflector bars all extend exclusively downstream from their attachment point on the support towards the flow-through casing. The deflector bars all extend radially outwards and, starting from the support, pass outside the inlet opening, maintaining a distance from the flow-through casing.

[0010] A disadvantage of the known screen or grid devices is that debris can become trapped between the grid bars and at the inlet edge, thereby obstructing the water flow through the turbine. This debris then has to be removed manually, which is time-consuming.

[0011] The object of the invention is to create a flow power plant of the type mentioned above, which avoids or at least reduces the disadvantages known from the prior art. The flow power plant should reliably prevent the accumulation of debris at the inlet guard or inlet opening, which would impede the flow of water over the turbine and thus reduce the efficiency of the flow power plant. Furthermore, the flow power plant should be designed to be as reliable, low-maintenance, and cost-effective as possible.

[0012] For this purpose, the invention provides a flow power plant as defined in claim 1. Advantageous embodiments and further developments are specified in the dependent claims.

[0013] The problem is solved by arranging the rods at an angle between 30° and 80° to the longitudinal axis of the housing and by having a diffuser in the housing between the inlet and outlet openings. The flow power plant is thus designed for installation in flowing water to generate electricity driven by the flowing water. The water body can be of natural origin and, in particular, be a free-flowing body of water such as a river or an artificially generated liquid stream. The flow power plant has a housing with an inlet opening and an outlet opening downstream of the inlet opening. The flowing water enters the housing through the inlet opening and exits the housing through the outlet opening. Preferably, the inlet opening and / or the outlet opening are round, in particular circular.A turbine, connected to a generator, is arranged in the housing between the inlet and outlet openings. The turbine preferably has turbine blades against which the flowing water acts, causing an output shaft connected to the turbine blades to rotate. The turbine drives the generator, particularly via the output shaft, which produces electricity. For efficient power generation, the turbine, and preferably also the inlet opening, is positioned as completely as possible within the flowing water, i.e., below the water surface, when the run-of-river power plant is in operation. The run-of-river power plant also features an inlet guard located upstream of the inlet opening. The inlet guard protects the inlet opening from debris that meets minimum dimensions specified by the guard.For example, the inlet guard can prevent debris such as tree trunks, branches, or plant parts in general, as well as waste like plastic parts, plastic films, packaging material, etc., from passing through the inlet opening. Such debris would not only impede the flow of water into the housing, but could also become entangled in the turbine or generator and hinder its rotation. The inlet guard comprises a mounting device connected to the housing and protective elements attached to the mounting device. The mounting device is preferably designed to be sufficiently robust and break-resistant to withstand impacts from debris with minimal damage. The protective elements attached to the mounting device also prevent large debris from entering the housing.

[0014] To prevent debris from accumulating on the inlet guard or the edge of the inlet opening, the protective elements are designed as rods oriented at an acute angle to a longitudinal axis of the housing when viewed downstream. This longitudinal axis runs essentially through the center point of the inlet opening and the center point of the outlet opening. The rods have a fixed end securely mounted to the holding device and a free end located outside the housing. Thus, the rods extend downstream from the holding device located upstream of the inlet opening towards the housing. The securely mounted end is rigidly connected to the holding device, ensuring a particularly reliable and low-maintenance connection.The free end, positioned outside the housing and not connected to it, allows debris adhering to or caught in the rods to be brushed off by the water flow. Because the free end is located outside the housing, the debris can be guided past the inlet opening after being brushed off. To further prevent brushed debris from entering the housing through the inlet opening, the distance from the mounting end to the free end is greater than the distance from the mounting end to an outer edge of the housing surrounding the inlet opening. Thus, the rods extend beyond the outer edge of the housing surrounding the inlet opening, meaning they extend downstream to beyond the inlet opening.

[0015] The flow power plant can be manufactured with particularly low maintenance due to the stable, i.e., rigid, mounting of the attachment end and the free end being located outside the casing. The extension of the rods beyond the inlet opening provides additional protection for the turbine and generator against debris.

[0016] According to the invention, the rods are arranged at an angle between 30° and 80° to the longitudinal axis of the housing. This angle can vary during operation of the flow power plant due to the elastic properties of the rods. Therefore, the angle value is preferably defined when the rods are unloaded, for example, outside of the water. A large value within this angle range allows for a short design of the flow power plant but also increases resistance when debris impacts the rods. Conversely, a small value within this angle range allows debris to slide off the rods with minimal resistance.

[0017] To increase the efficiency of the tidal power plant, the casing features a diffuser between the inlet and outlet openings. The diffuser is designed to increase the flow velocity at the turbine level, thereby enhancing energy yield, and to guide the water efficiently (ideally without turbulence, backflow, or flow separation) through the power plant. The diffuser must be designed to withstand the resulting pressures without damage.

[0018] When the description refers to locations and directions such as "above," "below," "front," "back," "upstream," "downstream," or "sideways," these refer to the intended operating condition of the run-of-river power plant. In its intended operating condition, the run-of-river power plant is positioned in a predominantly horizontal or slightly downward-sloping water flow, such as in a river. The term "vertical" means in the direction of gravity, from "above" to "below," or vice versa. If the run-of-river power plant is to be used in a different position, the location and direction specifications must be adjusted accordingly.

[0019] If two adjacent poles are arranged at a distance of between 10 cm and 40 cm, preferably between 20 cm and 30 cm, large debris, as well as people in the water, can be kept away from the interior of the housing. Several poles can be arranged at different distances from each other even when unloaded. Furthermore, the distance between two adjacent poles can vary along their length, even when unloaded. Additionally, the distance between the poles can vary over time due to the water flow acting upon them. For example, the distance between two adjacent poles can increase in the direction of the flow so that debris carried along in the direction of the current is not trapped between poles that are increasingly separated.

[0020] To facilitate the detachment of debris from the poles, the poles can be designed with a helical shape. This helical form results in varying angles between the pole surface and the water flow, allowing the water flow to detach the debris more easily and quickly, at least at certain points along the pole. The helical poles can, in particular, have at least one turn.

[0021] The removal of debris from the rods can be further facilitated by making the rods from spring steel or a material with a modulus of elasticity between 170 kN / mm² and 250 kN / mm². Rods designed in this way are sufficiently elastic to oscillate when the hydroelectric power plant is in operation, i.e., in the water flow. In particular, heavy debris such as branches or tree trunks can cause the rods to vibrate upon impact, thereby shaking off debris already adhering to them. The elastic properties of the rods thus enable the inlet guard to self-clean.

[0022] It is particularly advantageous if the rods are designed to oscillate elastically between an unloaded rest position and a loaded position, and if the position on the rods closest to the housing is at least twice as far from the housing in the rest position as in the loaded position. According to this embodiment, the rods can therefore oscillate around a rest position during operation, which they would also assume outside the water flow. The loaded position is assumed by the pressure of the water flow or the floating material on the rods. The greater the amplitude of the oscillation, the more reliably the floating material detaches from the rods. Therefore, it is advantageous if the deflection of the rods is such that the position on the rods closest to the housing is at least twice as far from the housing in the rest position as in the loaded position.The distance between the position on the rod closest to the housing and the housing is referenced to the point on the housing that is closest to the rod.

[0023] Preferably, the rods are designed to be sufficiently elastic and are mounted at a distance from the housing in their rest position such that at least one rod, in the load position, rests against the housing at the point closest to it. In this way, the oscillating rod can strike the housing, which further sets the rod into vibration and shakes off any debris adhering to it.

[0024] The vibration of the rod can also be intensified by positioning the rod at a greater distance from the free end. This allows the free end of the rod to be positioned at an even greater distance under load compared to its resting position, resulting in stronger vibration.

[0025] For the design of the inlet guard, it is advantageous if the retaining device has at least one longitudinal body and at least two mounting ends spaced apart from each other along this longitudinal body. The longitudinal body, which is spaced apart from the inlet opening, can be arranged at least partially symmetrically to the longitudinal axis of the housing. The longitudinal body can be straight or at least partially curved. If a single longitudinal body is provided, it can be positioned at one location on the longitudinal axis of the housing. The longitudinal body is particularly likely to be arranged at an angle to the longitudinal axis of the housing that deviates from 0°, for example, at an angle in the range of 30° to 90°. The longitudinal body can have two ends, and both ends can be connected to the housing.Due to the longitudinal extension of the longitudinal body, the force acting on the rods during operation of the flow power plant can be transferred to the holding device and from there to the housing using weaker and therefore more cost-effective components, compared to a ring-shaped holding device. At least two fastening ends can be arranged at the same or different distances from each other on at least one longitudinal body.

[0026] Regarding the design of the inlet guard, it is advantageous for the rods to have a diameter between 10 mm and 30 mm, preferably between 15 mm and 25 mm, and particularly around 20 mm, and / or a length between 0.5 m and 10 m, preferably between 0.5 m and 2 m. Rods with these dimensions can effectively protect the turbine and generator in the casing even from heavy debris such as tree trunks. In any case, the length of the rods must be sufficiently long so that the inlet opening is completely covered by the rod assembly, apart from the gaps between the rods, when viewed along the longitudinal axis of the casing. If the rods have a rectangular cross-section, their diameter is the diameter of their circumscribed circle. The length of the rods is measured between the fixed end and the free end.

[0027] If the poles are round in cross-section, especially circular, i.e., the poles are essentially free of edges, the flotsam is less likely to adhere to the poles and any flotsam already adhering to them can be more easily detached by the water flow.

[0028] Furthermore, the rods may be bent in the region of their free end. The free end may extend, for example, along a maximum of 20%, and in particular along a maximum of 10%, of the rod's longitudinal extent from the free end. Specifically, the rods may be bent outwards, i.e., away from the housing. Additionally, the diameter of the rods may decrease continuously in the region of their free end, for example by at least 30%, and in particular by at least 50%, until reaching the free end.

[0029] According to a further embodiment, the housing can be connected to a float. The float is preferably located in an upper region of the hydroelectric power plant and provides buoyancy to the power plant in the water. In particular, the float can be designed as a gas-filled hollow body. The float can be connected to an adjustment device to allow the buoyancy in the water to be adjusted.

[0030] The invention will be further explained below with reference to preferred, non-limiting embodiments and the drawings. The drawings show: Fig. 1 a flow power plant according to the invention in a perspective view; Fig. 2 the flow power plant made of Fig. 1 in a top view; Fig. 3 the flow power plant made of Fig. 1 in a side view; Fig. 4 the flow power plant made of Fig. 1in a view in the direction of flow; Fig. 5 a helically shaped rod of the inlet guard of the flow power plant made of Fig. 1 ; and Fig. 6 a curved rod of the inlet guard of the flow power plant made of Fig. 1 .

[0031] It should be noted that the Figures 1 to 6 The figures are not necessarily drawn to scale. Furthermore, for the sake of simplicity, not all components of the hydroelectric power plant are shown in all figures.

[0032] Fig. 1Figure 1 shows a run-of-river power plant 1 for installation in flowing waters G. In the illustrated example, the water body G has a flow direction S. The run-of-river power plant 1 has a casing 2, which has an inlet opening 3 and, downstream of the inlet opening 3, i.e., in the flow direction S after the inlet opening 3, an outlet opening 4. A turbine 5 is arranged in the casing 2 between the inlet opening 3 and the outlet opening 4, which is connected to a generator 6. The generator 6 can be arranged between the inlet opening 3 and the outlet opening 4 or as shown in Figure 2. Fig. 1The turbine 5 is mounted in the direction of flow S upstream of the inlet opening 3 and, in particular, attached to the housing 2. Thus, the flowing water, or another flowing liquid, can enter the interior of the flow power plant 1, which is enclosed by the housing 2, through the inlet opening 3, set the turbine 5 located in this interior in motion, and exit the flow power plant 1 again through the outlet opening 4. The rotating turbine 5 drives the electric generator 6, which generates electricity. The generated electricity can be transmitted via electrical conductors connected to the generator 6 (not shown in the figures). The housing 2 has a diffuser 14 between the inlet opening 3 and the outlet opening 4. The housing 2 can also be connected to a float 15.To protect the turbine 5 from debris and to prevent injury to people from the rotating turbine 5, the hydroelectric power plant 1 has an inlet guard 7 upstream of the inlet opening 3. The inlet guard 7 has a retaining device 8 connected to the housing 2 and protective elements 9 attached to the retaining device 8. The retaining device 8 is preferably rigidly connected to the housing 2. The protective elements 9 are designed to protect debris, people, and larger animals from entering the housing 2.

[0033] To allow the water body G to flow over the turbine 5 as freely as possible and to divert debris impacting the hydroelectric power plant 1 without damaging it, the protective elements 9 are rods 9a oriented downstream at an acute angle α to a longitudinal axis A of the casing 2. The rods 9a can have a round cross-section, particularly a circular one. A design for the hydroelectric power plant 1 that minimizes damage during operation and reduces maintenance requirements is particularly important, as repairs and maintenance work on the hydroelectric power plant 1 are very costly. Either the work must be carried out in the water, or the hydroelectric power plant 1 must be lifted out of the water and repaired on land.Therefore, it is particularly important that the rods 9a are not only robustly designed to withstand the impact of flotsam, but also mounted as stably and requiring as little maintenance as possible. For this purpose, the rods 9a are provided with a fixed end 10 and a free end 11, with the fixed end 10 being stably mounted to the holding device 8 and the free end 11 being located outside the housing 2. The stable, i.e., rigid, attachment of the fixed end 10 to the holding device 8 is particularly reliable and trouble-free. Maintenance and repair work on a fastening device between the rod 9a and the holding device 8 can thus be avoided or reduced. The rods 9a can be permanently connected to the holding device 8, for example, by welding.Alternatively, the rods 9a can be detachably connected to the holding device 8 to facilitate the replacement of damaged rods 9a with undamaged ones. For example, the rods 9a can be screwed to the holding device 8, and / or clamped, and / or inserted into a receiving device of the holding device 8. Essentially, a free space without components of the flow power plant 1 remains between the free end 11 and the housing 2. The free end 11 facilitates the removal of debris adhering to the rods 9a by the water flow. Thus, the inlet guard 7 is self-cleaning.

[0034] The rods 9a can have a diameter D (see Figs. 5 and 6) in the range between 10 mm and 30 mm, preferably between 15 mm and 25 mm, in particular of about 20 mm, and / or have a length L in the range between 0.5 m and 10 m, preferably between 0.5 m and 2 m. For example, the inlet guard 7 can have at least 5 bars 9a, in particular between 10 and 50 bars 9a.

[0035] In the Figs. 1 and 2It is further clearly evident that the distance D1 from the fastening end 10 to the free end 11 is greater than the distance D2 from the fastening end 10 to an outer edge 12 of the housing 2 surrounding the inlet opening 3. For example, the distance D1 from the fastening end 10 to the free end 11 is between 5 cm and 30 cm greater than the distance D2 from the fastening end 10 to the outer edge 12. In this way, the ingress of debris into the interior of the housing 2 can be reliably prevented. In addition, debris stripped or shaken off the rods 9a is reliably guided past the inlet opening 3. By keeping the free end 11 at least temporarily away from the housing, 2,in particular from the outer edge 12 of the housing 2, no debris which is carried along the rods 9a by the water current can become trapped between the rods 9a and the outer edge 12 of the housing 2 and thereby at least partially close the inlet opening 3.

[0036] In Fig. 2 It is clearly evident that the rods 9a are oriented downstream at an acute angle α to the longitudinal axis A of the housing 2. Thus, viewed in the flow direction S, the free end 11 is positioned further forward than the fastening end 10. The angle α between the rods 9a and the longitudinal axis A of the housing 2 is between 30° and 80°.

[0037] The Fig. 1 , 3 and 4Figure 1 further shows that the rods 9a can be spaced apart from one another. Two adjacent rods 9a can be arranged at a distance of between 10 cm and 40 cm, preferably between 20 cm and 30 cm. In particular, several or all rods 9a can be arranged such that adjacent rods 9a are spaced between 10 cm and 40 cm, preferably between 20 cm and 30 cm. At least two rods 9a can be aligned parallel to each other. At least two other rods 9a can be aligned at an angle other than 0 degrees, i.e., not parallel to each other.

[0038] In Fig. 2It is also apparent that the rods 9a can be designed to oscillate elastically between an unloaded rest position RP and a loaded position LP. Furthermore, it is apparent that a position NP on the rods 9a closest to the housing 2 can be at least twice as far from the housing 2 in the rest position RP as in the loaded position LP. Fig. 2The rod 9a in the load position LP is shown with a dashed line, and the nearest position NP is symbolized by a thickened dot on the rod 9a in the rest position RP. For example, the position NP nearest to the housing 2 on the rods 9a in the rest position RP can be between 5 cm and 15 cm away from the housing 2, in particular from the outer edge 12 of the housing 2 surrounding the inlet opening 3. If the rods 9a are to be designed to oscillate, they are preferably made of spring steel or of a material with a modulus of elasticity in the range between 170 kN / mm² and 250 kN / mm². At least one rod 9a can be designed such that, under the expected or prevailing flow conditions in the load position LP, the position NP nearest to the housing 2 is in contact with the housing 2 at least temporarily. This contact with the housing 2 is described in Fig. 2It is not shown, but can easily be understood by a professional.

[0039] Using the example according to Fig. 2 It is also apparent that the nearest position NP can be spaced from the free end 11, i.e., offset from the free end 11 in the direction of the fastening end 10. For example, the nearest position NP can be spaced between 5 cm and 30 cm from the free end 11. This allows the free end 11 to swing even more freely and shake off debris when the rod 9a strikes the housing 2 at the position NP nearest the housing 2.

[0040] According to the in the Fig. 1 and 3 In the examples shown, the holding device 8 can have at least one longitudinal body 13, and at least two fastening ends 10 can be spaced apart from each other and mounted along the at least one longitudinal body 13. In the examples according to Fig. 1 and 3Two longitudinal bodies 13 are provided. The longitudinal bodies 13 can, for example, be designed as profile bars or tubes. The holding device 8 can also have a casing 16, in which the generator 6 is preferably received. The longitudinal bodies 13 can be arranged along a line and connected to the casing 16 at their ends facing each other, in particular supported on it. At least one rod 9a can be attached to the casing 16.

[0041] Fig. 4 The graph shows the flow power plant 1 in a view in the direction of flow S.

[0042] Fig. 5 Figure 1 shows an example of a rod 9a which is helically shaped. For this purpose, the rod 9a can be twisted about its longitudinal axis, at least in sections. At least one or all of the rods 9a can be helically shaped.

[0043] Fig. 6Figure 1 shows an example of a rod 9a, which is designed as a bent rod 9b. At least one or all rods 9a can be designed as bent rods 9b.

[0044] For example, a prototype of the flow power plant 1 has a length of 11.3 m, a maximum width at the diffuser 14 of 5.5 m, a maximum height of 3.4 m, and a weight of 9300 kg. The casing 2 can be made of steel.

Claims

1. A flow power plant (1) for installation in flowing waters, comprising a housing (2) which has an inlet opening (3) and downstream of the inlet opening (3) an outlet opening (4), wherein a turbine (5) is arranged in the housing (2) between the inlet opening (3) and the outlet opening (4), which is connected to a generator (6), and with an inlet guard (7) arranged upstream of the inlet opening (3), which has a retaining device (8) connected to the housing (2) and protective elements (9) attached to the retaining device (8), wherein the protective elements (9) are rods (9a) oriented downstream at an acute angle (α) to a longitudinal axis (A) of the housing (2) with a fastening end (10) stably mounted on the retaining device (8) and a free end (11) arranged outside the housing (2),wherein a distance (D1) from the fastening end (10) to the free end (11) is greater than a distance (D2) from the fastening end (10) to an outer edge (12) of the housing (2) surrounding the inlet opening (3), , characterized by the fact that the rods (9a) are arranged at an angle (α) between 30° and 80° to the longitudinal axis (A) of the housing (2) and the housing (2) has a diffuser (14) between the inlet opening (3) and the outlet opening (4).

2. Flow power plant (1) according to claim 1, characterized by the fact that two adjacent rods (9a) are arranged at a distance between 10 cm and 40 cm, preferably between 20 cm and 30 cm, from each other.

3. Flow power plant (1) according to claim 1 or 2, characterized by the fact that the rods (9a) are helically shaped.

4. Flow power plant (1) according to one of claims 1 to 3, characterized by the fact that the rods (9a) made of spring steel or of a material with a modulus of elasticity in the range between 170 kN / mm 2 and 250 kN / mm2 are educated.

5. Flow power plant (1) according to one of claims 1 to 4, characterized by the fact that the rods (9a) are designed to oscillate elastically between an unloaded rest position (RP) and a load position (LP) and a position (NP) on the rods (9a) closest to the housing (2) is at least twice as far from the housing (2) in the rest position (RP) as in the load position (LP).

6. Flow power plant (1) according to claim 5, characterized by the fact that at least one rod (9a) in the load position (LP) is in contact with the housing (2) at the position (NP) closest to the housing (2).

7. Flow power plant (1) according to claim 5 or 6, characterized by the fact that the nearest position (NP) is spaced from the free end (11).

8. Flow power plant (1) according to one of claims 1 to 7, characterized by the fact thatthe holding device (8) has at least one longitudinal body (13) and at least two fastening ends (10) are spaced apart from each other and are mounted along the at least one longitudinal body (13).

9. Flow power plant (1) according to one of claims 1 to 8, characterized by the fact that the rods (9a) have a diameter (D) in the range between 10 mm and 30 mm, preferably between 15 mm and 25 mm, in particular of about 20 mm and / or a length (L) in the range between 0.5 m and 10 m, preferably between 0.5 m and 2 m.

10. Flow power plant (1) according to any one of claims 1 to 9, characterized by the fact that the rods (9a) are round in cross-section, in particular circular.

11. Flow power plant (1) according to one of claims 1 to 10, characterized by the fact that the housing (2) is connected to a float (15).

Images