PHOTOVOLTAIC UNIT FOR WATERS

Description

[0001] The invention relates to a photovoltaic unit for use on water bodies, in particular at sea.

[0002] Photovoltaics (hereinafter abbreviated to "PV") has experienced dramatic development worldwide in the two decades since 2000. There is also a trend toward the construction of PV power plants on inland waterways and in the maritime sector.

[0003] EP 3 845 826 A1, for example, describes a floating structure with solar modules that can be adjusted in azimuth to optimize solar radiation, with the solar modules being submerged below the water surface. Furthermore, WO 2010 / 026542 A1 discloses the placement of solar modules on inland waterways just below the water surface to increase their efficiency.

[0004] Against this background, the object of the present invention was to provide means for the efficient and safe operation of photovoltaic units, particularly on maritime waters.

[0005] This object is achieved by a PV unit according to claim 1 and by a method according to claim 12. Advantageous embodiments are contained in the subclaims.

[0006] Where numerical values ​​for parameters are mentioned in the following description, these are generally to be understood as approximate values, so that numerical values ​​within a range of ± 25% are typically also included. When gradations of preferred parameter values ​​are mentioned, all intermediate values ​​are also implicitly included.

[0007] The PV unit according to the invention is intended to be particularly suitable for use on bodies of water such as inland lakes or, above all, the sea. It is used to generate electrical energy from incident sunlight, which energy is typically used or stored by a local consumer or a remote consumer, particularly on land. The PV unit contains the following two components: A module array with at least one PV module. A field holder designed to move the module array between an operating position at the water surface and (at least) one submerged position below the water surface.

[0008] As usual, the term "PV module" refers to the smallest structurally coherent unit with means for converting incident light energy into electrical energy. The geometric shape of the PV module is essentially arbitrary. Typically, a PV module is essentially flat with a flat or curved (e.g., outwardly curved) surface and has an area of ​​one to several square meters.

[0009] In the simplest case, the "module array" can consist of a single PV module. Typically, however, it contains multiple PV modules connected together via rigid or flexible mechanical and typically also electrical connections. The module array preferably consists of flexibly coupled rigid PV modules (or PV units composed of multiple PV modules), which are essentially spaced at fixed distances from each other. Furthermore, the module array typically includes a connection or interface through which the electrical energy generated by the PV modules can be extracted. For example, a rechargeable battery and / or other electrical energy consumers and / or a cable leading to the shore can be connected to this interface.

[0010] In the "operating position," the module array should be at the water surface, which, by definition, means that at least one PV module is in a position where it can generate electrical energy when exposed to sunlight. Typically, the sensitive surface of the PV module is located above the water surface. However, it can also be located slightly below the water surface if this does not significantly impair light absorption.

[0011] The "submerged position" is located at a depth below the water surface determined depending on the application. In one important application, the submerged position serves as a "protective position" and is characterized by the fact that a module array located there is so far removed from the influences of wind and / or waves that no damage is to be feared. Typically, the submerged position or the protective position is located at a depth that corresponds to one or more times the prevailing wave height. Additionally or alternatively, the submerged position or the protective position can also be characterized by the wavelength, i.e., the horizontal distance between two wave crests. For example, the protective position can be assumed to be at a depth of approximately 10%, approximately 20%, approximately 30%, approximately 40%, approximately 50%, approximately 60%, approximately 70%, approximately 80%, approximately 90%, approximately 100%, approximately 120%, approximately 150%, approximately 200%, or more of the prevailing wavelength.Furthermore, additionally or alternatively, the diving position or the protection position can be located at a depth at which the average or maximum flow velocity of the surrounding water is less than approximately 10 m / s, less than approximately 5 m / s, less than approximately 2 m / s, less than approximately 1 m / s, less than approximately 0.5 m / s, less than approximately 0.25 m / s, less than approximately 0.1 m / s, or less than approximately 0.05 m / s. Typical absolute numerical values ​​for the protection position are approximately 5 m, approximately 10 m, approximately 15 m, approximately 20 m, approximately 30 m, approximately 40 m, approximately 50 m, approximately 60 m, approximately 70 m, approximately 80 m, approximately 100 m, approximately 150 m, approximately 200 m or more than 200 m below the water surface.

[0012] In another application, the submerged position serves as a "cleaning position," characterized by the fact that the surface of the PV modules is washed and cleaned by water in this position. The cleaning position is usually located relatively close to the water surface, for example, in an area up to 1 m below the level of the troughs of the prevailing wave swell. In particular, it can be located above the depths mentioned above as examples for the protection position, for example, at approximately 0%, approximately 5%, approximately 10%, approximately 30%, approximately 50%, or approximately 75% of the protection position (measured from the water surface).

[0013] Another conceivable application could be that power production is to be interrupted or reduced by incoming sunlight, and the PV modules are lowered into a submerged position, in which a correspondingly high proportion of the sunlight is absorbed by the water. Furthermore, lowering into a submerged position can also be used for cooling purposes, maintenance purposes, traffic reasons (ship passage), or similar.

[0014] As explained, the exact location of the diving position can vary widely depending on the application and environmental conditions. Typically, it can be approximately 5 m, approximately 10 m, approximately 15 m, approximately 20 m, approximately 30 m, approximately 40 m, approximately 50 m, approximately 60 m, approximately 70 m, approximately 80 m, approximately 100 m, approximately 150 m, approximately 200 m, or more than 200 m below the water surface. Of course, any intermediate values ​​to the stated depths can be assumed, and there can also be multiple diving positions, which can be assumed depending on the situation (weather, time of day, etc.).

[0015] The PV unit according to the invention has the advantage that it can also be operated safely and efficiently on open waters, since its PV modules can be moved to a suitable submerged position below the water surface, for example for protection or cleaning purposes.

[0016] In principle, the entire PV unit could be a floating structure, which can be dynamically positioned horizontally as desired, for example by drives. According to the invention, the field holder is equipped with fixing means for direct or indirect coupling to the ground and / or to the water surface. The field holder can be coupled to a point or at least a surface (water surface) by the fixing means, so that in this sense it is fixed in a fixed bearing or at least a loose bearing. The ground can be the waterbed or soil on land. The fixing means can couple to the ground directly (e.g. anchors and / or weights and / or piles), but also indirectly, for example via suitable fixed points which are themselves connected to the ground (e.g. artificial islands, offshore structures, fish farms).In this embodiment, the module array is typically coupled to the array holder in a positionally variable manner, allowing it to be moved between the operating position and a submerged position below the water surface. Otherwise, the shape and design of the array holder is freely selectable. In particular, it can be a net-like structure with flexible traction means, such as ropes or chains, and / or with rigid connections, such as rods. Advantageously, the net-like structure can comprise strands running vertically or diagonally from top to bottom (which typically connect to the ground and / or the water surface), which are coupled to one another by substantially horizontal strands on one or more horizontal planes.

[0017] Additionally or alternatively, the fixing means can also be designed to couple to a flying object such as a balloon.

[0018] The field holder can, in particular, be fixed to at least one point on the waterbed or another suitable fixed point. It is preferably fixed to two, three, four, or more points on the waterbed. In particular, fixing points can be arranged along the periphery of the field holder, viewed in a vertical projection, so that the field holder is held between them essentially in a fixed (horizontal) position. The field holder can be fixed to the waterbed, for example, using weights and / or ground anchors and / or piles connected to the field holder. The term "fixation" therefore does not necessarily mean a one-piece connection to the waterbed. Rather, a connection to a point on the waterbed that is fixed under the typically occurring forces is sufficient. Furthermore, as already mentioned, the field holder can be formed internally in a network-like manner, essentially by rigid and / or flexible connections.Preferably, the structure is designed so that the couplings can be formed solely by flexible, yet tensile-resistant elements such as ropes or chains. Furthermore, the field holder can, in particular, contain vertical rigid structures such as piles, along which the module field can be moved, e.g., in the same way as with the cylindrical buoys described later.

[0019] The field holder preferably contains at least one buoyancy body, i.e., a body that generates buoyancy in the water directed toward the water surface. Such a buoyancy body makes it possible to exert forces directed toward the water surface on the field holder in order to hold it in a specific configuration. For example, the field holder can be attached to the water surface using a buoyancy body, acting as a floating bearing. The buoyancy body can be located at the water surface with the installed PV unit and protrude above the water, but it can also be completely submerged in the water.

[0020] The module array is further coupled to the array holder in such a way that it is movable relative to it, at least (or exclusively) in one direction. In the installed PV unit, this direction is typically vertical, so that the module array is only movable relative to the array holder in the vertical direction, for example, but its horizontal position is essentially fixed. The array holder, fixed to the water floor and / or surface, then forms a kind of frame along which the module array can move to switch between the operating position and the submerged position.

[0021] When moving the module array from its operating position to the submerged position, the array holder will typically remain stationary relative to the surroundings (seabed, etc.) while the module array moves. Optionally, however, the array holder can also move (along with) the array, at least partially. Furthermore, it is conceivable that the array holder as a whole is movable and / or changeable in shape, for example, lowerable toward the waterbed.

[0022] In the following, various advantageous further developments of the PV unit are described, which can be implemented individually or in any combination with each other.

[0023] According to a further development, the coupling between the module array and the array holder is designed such that the module array can only move up to a stop position relative to the array holder. Optionally, both directions of movement can each be limited by a stop position. A stop position can be provided in particular for the downward movement of the module array towards the waterbed in order to keep it at a certain water depth and prevent it from sinking completely to the waterbed. For the upward movement towards the water surface, a stop position is also advantageously provided, for example to prevent the array holder from becoming detached from the module array and / or to set defined coupling properties between the array holder and the module array in the area of ​​the water surface, which influence the overall dynamic behavior of the PV unit.

[0024] Preferably, the module array contains (at least) one buoyancy body or is coupled to at least one buoyancy body. This makes it possible to exert a force directed toward the water surface on the module array, for example, to hold it in its operating position at the water surface. Suitable buoyancy bodies include, for example, closed hollow chambers filled with air.

[0025] Additionally or alternatively, the module array and / or the array holder can contain (at least) one downforce body with variable downforce or be coupled thereto. A "downforce body" is understood to be a component that can exert downforce, i.e., a force directed toward the waterbed. Due to the variability of the downforce, the strength of the downforce force can be controlled. Preferably, the downforce lies between a maximum value and a value of or close to zero, the latter corresponding to a body suspended in the water. Optionally, the downforce force can also be reduced to negative values, i.e., convert into buoyancy toward the water surface. The downforce force can be generated, in particular, by the deadweight of the downforce body, with its magnitude resulting, according to Archimedes' principle, from the difference between the weight of the displaced water volume and the weight of the downforce body.Such a variation in output can be achieved in a simple manner by the controlled filling of a cavity with a light gas such as air or hydrogen (H 2 ).

[0026] Additionally or alternatively, the module array and / or the array holder may contain or be coupled with (at least) one buoyancy body with variable buoyancy. Its technical implementation can be analogous to the output body with variable output described above.

[0027] Generally speaking, the entire module field, including its PV modules, connections, buoyancy bodies, drift bodies, etc., forms a single unit, which can exhibit a certain positive or negative buoyancy (i.e., downforce) in the water. This total buoyancy must ultimately be adjusted so that it is positive (directed toward the water surface) for assuming the operating position and negative (directed toward the water bottom) for assuming the submerged position. Such regulation can be achieved, for example, using drift bodies and / or buoyancy bodies with variable buoyancy.

[0028] It has already been mentioned that, in the simplest case, the module array can consist of a single PV module. Preferably, however, the module array contains two or more PV modules that are flexibly coupled and / or spaced apart. In particular, multiple PV modules can be rigidly and / or flexibly coupled to form PV elements, which in turn are flexibly connected to the module array.

[0029] In a further embodiment of the invention, the field holder has at least one substantially vertically extending guide element to which the module field is movably coupled (preferably linearly movable). The module field can then be moved in a defined manner and on a defined path along the guide element. Preferably, a plurality of such guide elements are provided, which are arranged distributed in the horizontal plane, typically extend over approximately the same water depth, and along which the module field is guided during movement relative to the field holder. In particular, such guide elements can be arranged at intervals along the periphery of the module field. Furthermore, in preferred embodiments, the guide elements can protrude vertically upwards from a base of the field holder, which base is anchored to the waterbed.The guide elements can be rigid bodies that are held in their vertical orientation by appropriate devices (traction means, rods, etc.). Additionally or alternatively, the guide elements can contain buoyancy bodies that effect their alignment and positioning in the water. According to a further embodiment, the guide elements can be rigid posts, rods, or the like that are attached in or to the ground.

[0030] In a further development of the invention, the aforementioned guide element has a movably mounted running unit to which the module field is (in particular detachably) connected or connectable. The movement of the running unit along the remaining guide element can then be designed in a defined manner, for example via appropriate roller bearings, heavy-duty rollers, or plastic slide rails. Preferably, the running unit is essentially linearly movable and / or optionally non-rotatable or limited in its rotational mobility with respect to the axis of the guide element. In particular, overrotation of the running unit can be structurally excluded, for example, multiple rotations around the axis of the guide element.

[0031] According to another development of the invention, the mobility of the module array relative to the array holder is variable, preferably adjustable. The variability can, in principle, cover the entire spectrum between "freely movable" and "locked in a specific position" or a sub-range thereof (where "free mobility" is to be understood practically and can, for example, include unavoidable friction). A reduction in mobility can, for example, be used to slow the movement speed of the module array and thus reduce the force loads in the PV unit. In particular, the movement of the module array in the downward or upward direction can be slowed down when it approaches one of the aforementioned stop positions. A complete suspension of mobility (locking) can be used to move the module array as needed and depending on the situation (e.g.Example: depending on the strength of the waves) to hold at a desired diving position.

[0032] The described variability of the mobility of the module array relative to the array holder can, for example, consist in the fact that during the design (construction) of a PV unit for the area of ​​application (inland waters, bay, open sea, etc.) a suitable mobility is specified and, for example, implemented structurally (by specifying certain distances, tightening screws, pre-tensioning spring elements that, for example, press slide rails onto sliding surfaces and thus generate a defined frictional force, etc.). This mobility can then remain unchanged in the installed PV unit. The variability of the mobility can additionally or alternatively consist of a time-, location- and / or speed-dependent mobility. This can be implemented structurally, for example, by increasing the friction in certain movement sections.Optionally, the mobility can also be actively controlled using appropriate mechanical, hydraulic, electrical, or other actively actuated devices such as friction brakes. The corresponding actuators can be controlled, for example, using a central control unit on the PV unit and / or via a remote connection.

[0033] Quantitatively, the "mobility" can be described, for example, by the dynamic behavior of a long cylindrical buoy (see figures) when a force F is applied to the module field. If x is the position of a point in the module field (e.g., along a guide of the long cylindrical buoy (coupling point of the module field with the running unit of the long cylindrical buoy described later)), the following equation of motion can apply to the long cylindrical buoy along its vertical axis: x ¨ = a ⋅ F t + b ⋅ x + c ⋅ x ˙

[0034] The parameters a, b, and c can be constants or depend on time t, location x, and / or speed x, where a time dependence would, for example, reflect an explicit external control. The parameters capture dynamic processes such as friction, damping, spring behavior, elasticity, etc. The parameter a contains the information about the amplitude of the acting force F. The parameter b contains the information about the hydrostatic stiffness of the long cylindrical buoy. The parameter c contains the information about the damping intensity. By appropriately adjusting these parameters, the overall hydroelastic behavior of the PV unit with respect to the effects of waves can be optimized.

[0035] The buoyancy body contained in the field holder can, in particular, have an elongated shape, which can preferably be roughly described by a cylinder or a spindle (a cylindrical shape tapered at the ends). The width-to-length ratio of the buoyancy body is less than one (100%). It can preferably have a maximum value of 1:2 (corresponding to 50%), furthermore preferably a maximum of one of the values ​​40%, 30%, 20%, 10%, 5%, 2.5%, 2%, 1.5%, 1%, 0.5%, 0.1%, 0.05%, 0.01% or less. The elongated shape supports a stable position of the buoyancy body in the water. The longitudinal extension can, in particular, be oriented vertically. Another advantage is that the buoyancy body can extend into deep, relatively calm water zones, thereby providing additional stabilization.The absolute length of the buoyancy body is preferably at least 1 m, particularly preferably at least 2 m, 3 m, 4 m, 5 m, 6 m, 8 m, 10 m, 15 m, 20 m, 25 m, 30 m, 35 m, 40 m, 45 m, 50 m, 55 m, 60 m, 65 m, 70 m, 80 m, 85 m, 90 m, 95 m, 100 m, 120 m, 150 m, 200 m or more.

[0036] As already mentioned, the buoyancy body can, in particular, be configured to assume a vertical orientation in the water. For this purpose, for example, its density varies along its longitudinal extent, so that a head region of lower density is arranged above a foot region of higher density in the water. In particular, a weight with a higher density than that of the water can be arranged in the foot region of the buoyancy body.

[0037] According to another development, the module array can be movable along the buoyancy body of the array holder. This applies in particular if the buoyancy body, as described above, is aligned vertically in the water with a longitudinal extension. The buoyancy body then represents an example of a guide element of the type described above. The coupling of the module array to the buoyancy body is preferably designed as a linearly movable bearing. For example, an eyelet of the module array can comprise a rod-shaped buoyancy body. Likewise, as already mentioned, the buoyancy body can contain a movable running unit to which the module array can be coupled. Various embodiments will be explained in more detail later in conjunction with the figures.

[0038] The buoyancy body of the field holder can further comprise a damping element to dampen its movement in the water. The damping element can, for example, be designed as a (closed or perforated) plate or disc, which generates a high flow resistance perpendicular to its surface and thus dampens movements in this direction. The damping element can, in particular, be located on the buoyancy body in such a way that its upward and downward movement in the water is reduced. Furthermore, the damping element is preferably located in an area of ​​the buoyancy body that, in operating condition, is located away from the water surface or in relatively calm water layers.

[0039] At least one buoyancy body of the field holder can be configured to assume a position below the water surface (i.e., to be completely submerged) when the PV unit is in operation. In particular, this position can be in the range of the submerged position or below. Such a buoyancy body ensures that lower-lying parts of the field holder are correctly aligned or maintain a certain distance from the water bottom.

[0040] According to a further embodiment, at least one fixing means, which is intended for coupling to the ground and / or the water surface, can be located outside the surface of the module array in the vertical direction (projection). In this way, horizontal forces caused by currents, waves, wind, and the like can be absorbed, and the horizontal position of the module array can be fixed. It is particularly preferred if several fixing means are distributed around the module array, projecting outwards, in order to be able to absorb forces from different directions.

[0041] The PV unit described can be dimensioned depending on the application and requirements. It typically contains approximately 100–2000 conventional solar modules or a maximum energy generation of approximately 0.5–2 MWp.

[0042] Structurally, the PV unit typically represents a standalone system that can be installed in a body of water. However, multiple PV units can optionally be coupled to form large PV power plants by arranging them across an area and preferably interconnecting them with horizontal connections.

[0043] Typically, the module array of a PV unit can only be moved as a single unit between the operating position and a submerged position. In the PV power plants described above, however, the module arrays of the individual PV units can optionally be moved independently of each other. This allows the module arrays to be lowered differently depending on the situation, for example, more along the edge of the PV power plant than in the center.

[0044] The invention further relates to a method for operating a PV unit on a body of water, wherein the PV unit contains a module array with at least one PV module. The method is characterized in that the module array can be relocated, depending on the situation, between an operating position at the water surface and a submerged position below the water surface.

[0045] The method can be carried out, in particular, with a PV unit according to one of the embodiments described above. Therefore, the explanations given for the PV unit also apply mutatis mutandis to the method, and vice versa, even if this is not specifically mentioned below.

[0046] According to a preferred embodiment of the method, the module array is relocated to the submerged position ("protection position") when waves and / or storms exceed a given strength, whereby this wave and / or storm may already exist or is only just forecast. The relocation can be initiated by a user via the control system. In particular, however, it can also occur automatically depending on the measured values ​​from wave and / or storm sensors or depending on weather forecasts.

[0047] Additionally or alternatively, the modules can also be moved to the submerged position ("cleaning position") for cleaning purposes. Such a move can occur automatically at regular intervals and / or when the efficiency of the modules has fallen below a specified value due to salt and / or dirt deposits.

[0048] According to another option, the shift to the submerged position can be carried out if, for certain reasons (e.g. malfunction of the plant), the power production is to be interrupted or reduced.

[0049] Finally, the diving position can also be reached when the solar radiation (e.g. at night) is below a specified minimum value and the modules (e.g. for safety reasons) are better kept underwater than on the water surface.

[0050] The relocation of the module array can be achieved in various ways. For example, traction devices fixed to the waterbed could forcibly pull a buoyant module array beneath the water surface. In a preferred embodiment, however, the relocation occurs by changing the buoyancy and / or drag of the module array and / or of at least one body coupled to the module array. In other words, the state of the module array can be varied between "floating," "suspended," and "sinking."

[0051] Since the PV unit according to the invention consists of two separate components, namely the module field on the one hand and the field holder on the other, these represent independently marketable components. The scope of protection of the invention therefore also independently includes module fields which are suitable for a PV unit according to one of the above embodiments, as well as field holders which are suitable for a PV unit according to one of the above-described embodiments.

[0052] Likewise, the buoyancy bodies according to the embodiments described above can be independently transportable components and thus independent aspects of the invention.

[0053] The invention is explained in more detail below with the aid of exemplary embodiments and figures. Herein: Figure 1 shows a schematic perspective view of an installed PV unit; Figure 2 shows a side view of a single PV element with attached output body; Figure 3 shows a top view of the PV element of Figure 2 ; Figure 4 a side view of a module field with floating bodies attached to the PV elements; Figure 5 a side view of a module field with floating bodies attached between the PV elements; Figure 6 a separate perspective view of an installed field holder; Figure 7 a perspective view of an elongated buoyancy body (position buoy) with a vertically acting damping element and a cylindrical running unit; Figure 8 a section through the running unit of Figure 7; Figure 9 a perspective view of two embodiments of an elongated buoyancy body with vertically acting and horizontally acting damping elements and a running unit in a linear guide; Figure 10 a detailed view of the head area of ​​the buoyancy bodies of Figure 9 ; Figure 11 a detailed view of an example of the foot area of ​​an elongated buoyancy body with a buffered stop position, buoy holder and locking unit in a perspective (left) and a side view (right); Figure 12 a detailed view of an example of the upper area of ​​an elongated buoyancy body with buoy holder and locking unit; Figure 13 the overall view of a PV power plant constructed from a plurality of PV units; Figure 14 the PV power plant of Figure 13 without PV modules and PV elements; Figure 15 a plan view of the PV power plant of Figure 13 ; Figure 16a side view of the PV power plant of Figure 13 .

[0054] The embodiment of the invention described in the figures represents a largely flexible structure with the lowest possible flow resistance, which is also characterized by the possibility of vertically lowering essential functional components that could be destroyed by very strong winds and very high waves on the sea surface. This embodiment relates to small and large maritime photovoltaic power plants (PV power plants). Photovoltaic power plants of this type can, of course, also be operated in inland lakes and sheltered bays. The features mentioned in the examples can always be implemented separately and independently of the other features of the illustrated embodiments.

[0055] PV power plants can be constructed modularly from a suitable grouping of photovoltaic units (PV units). A PV unit 100 can, for example, have a size of one megawatt peak (1 MWp) and consist of, for example, one hundred PV elements 130, each with a power output of ten kilowatts peak (10 kWp). PV elements 130 can have a fixed or at least partially flexible frame with a specific buoyancy in conjunction with an adjustable downforce. The smallest unit of photovoltaic energy generation is the individual PV module 131. The PV modules are positioned on the PV elements 130 in a suitable manner and number.

[0056] For clarity, the following descriptions primarily refer to a single PV unit 100. The development described here solves the problem of excessive mechanical loads on the PV units, caused, among other things, by wave action, with a novel conceptual approach and specific design details.

[0057] Up to a certain wave height (maximum operating wave height), the individual PV elements 130 are located at a suitable height on the water surface GO, so that the PV modules 131 are at an optimal height above the water surface. The PV elements 130 are elastically connected to each other with ropes and / or spacers (121 in Figure 4, 5 ) are connected to a module field 120 in such a way that, in the case of a calm and flat sea surface, they have a defined distance from each other and the sum of the PV elements forms the basic shape of the PV element area located on the sea surface (e.g. a square field).

[0058] As the waves increase, the PV elements 130 essentially follow the wave motion up to a limit, the maximum operating wave motion. If the current wave motion exceeds the maximum operating wave motion, or if the weather forecast indicates that this will be exceeded within a short period of time, the PV elements 130 of the PV unit 100 are lowered in their entirety below the water surface, thus removing them from the influence of the wave motion of the water surface. Pressure fluctuations induced by the waves on the water surface, including oscillating water movements, decrease significantly with water depth. From a suitable water depth onwards, the influence of the dynamic processes on the water surface on the water depth is so minimal that the PV elements 130 lowered there experience only a low dynamic load.The required submersion depth is the water depth suitable for the PV elements, defined here as the "protection depth ST," at which the dynamic forces and water movements of the waves on the water surface and additional current forces have decreased to a permanently tolerable low level. The protection depth ST is a representative example of a general "submersion position" to which the PV modules can be submerged for various reasons (e.g., for cleaning purposes).

[0059] Additional flow forces also arise from other ocean currents, such as tides and other regional and supra-regional water currents. These currents will primarily be parallel to the horizontal plane of the PV elements 130 and must be considered as one of the loads occurring on the structure.

[0060] For the lowering process, the buoyancy of the PV elements 130 is reduced to such an extent that they sink. The fundamental problem here is how to limit the sinking to a specific depth, since a body that sinks underwater will, in principle, always sink to the bottom. In this case, the sinking depth is limited and defined in a simple and previously unknown manner by placing vertical boundaries 115 ( Figure 1 , "stop position") are created to stop the further sinking of the PV elements 130 at the protection depth. The vertical boundaries are connected by suitable connecting means to, for example, the position buoys 111 explained later, which bear the weight of the lowered PV elements. Buoys can also be positioned underwater at a suitable location, preferably at the level of the protection depth ST or below (e.g., stabilization buoys 116, Figures 6 , 16). The sinking of the PV elements 130 stops when they are prevented from sinking further by the vertical limits 115. In this case, the structure A, called the "field holder 110," with its positioning buoys 111, absorbs the vertical load of structure B ("module field 120" consisting of PV units 130). Optionally, the downforce of the PV units 130 could also be reduced to or close to the floating point in the protection depth.

[0061] The lowering process of the module field 120 can additionally or alternatively be stopped or slowed down by weights (not shown) attached to the module field hanging downwards, resting on the water bottom at a suitably adjusted depth and thus no longer exerting any pulling force.

[0062] For further explanation, a possible embodiment of a PV unit 100 is described. In principle, the PV unit can advantageously be roughly divided into two interconnected functional macrostructures.

[0063] Structure A, also called "field holder" 110, is the positioning structure for the entire PV unit ( Figure 1). It essentially consists of traction devices, positioning buoys (and possibly other buoyancy bodies), mechanical couplings, and suitable attachment points. Offshore wind turbines, fish farm structures, drilling platforms, and any other suitable structures can also be used as positioning buoys and / or attachment points. Structure A forms a horizontal boundary for the PV elements 130 at the sea surface GO (working position) and at a defined protection depth ST (diving position). For this purpose, structure A has connections to the seabed GB and / or the mainland and / or other fixed points in order to position the positioning buoys 111 with suitable accuracy at a horizontal position in the sea. The connections to the seabed can be established using traction devices 112, e.g., ropes, chains, or rods. The attachment of traction devices to the seabed is carried out using, for example, suitably dimensioned weights 113 (e.g.,concrete bodies) positioned on the seabed or at other fixed points.

[0064] Structure B is a module array 120 consisting of PV elements 130. Structure B (module array 120) is held in the desired described positions (working position, submerged position) by Structure A (array holder 110). The PV elements 130 have variable buoyancy, which is controlled centrally (for example, in a control unit (not shown) on the array holder or via wireless communication from shore). In the working position, the module array 120 floats independently; the horizontal position is predetermined by Structure A. When the submerged position is to be approached, the buoyancy of the PV elements 130 is reduced to such an extent that the module array 120 sinks from the working position to the submerged position. In the submerged position, Structure B (the module array 120) is held in the vertical position (submerged position) and in the horizontal position by Structure A, the array holder 110.For the lowering of the module field, for example, all PV elements 130 can have a stable horizontal position so that when the module field is lowered, only minimal forces (contact and friction forces, without tilting or tension) occur in the connection points of structure A and structure B and between the individual PV elements.

[0065] A PV element 130 ( Figure 2) typically carries several PV modules 131 and is an independently buoyant module of the module field 120: It consists, for example, of a rigid or at least partially flexible frame 132 made of a suitable material, e.g. seawater-resistant plastic and / or metal and / or another material with a defined buoyancy and a propulsion body 135 lying below the water surface GO. The propulsion body 135 has a controllable propulsion. The center of gravity of a PV element lies below the center of buoyancy and thus a stable position of the PV element 130 is ensured. In order to lower the PV element, the propulsion is increased until the PV element sinks. To surface, the propulsion is reduced until the buoyancy from the frame 132 exceeds the propulsion forces and the PV element 130 rises to the water surface.

[0066] In Figure 2A schematic cross-section of a propulsion body 135 is shown. This consists of a completely enclosed volume filled with a weight G, water WA, and air LU. The proportions of water and air can be controlled externally to adjust the desired propulsion toward the waterbed. The propulsion body 135 can contain a pump (not shown), electrical connections, and / or a communication device (e.g., for sound-based communication).

[0067] For the operation of electrical equipment such as motors, pumps, or the like, the PV unit 100 has the necessary electrical supply lines and optional energy storage devices (e.g., accumulators, not shown) from which the required electrical energy can be drawn. Additionally or alternatively, some PV modules can remain permanently on the water surface and not be submerged to ensure an emergency power supply.

[0068] Overall, the individual PV elements 130 should have little buoyancy, and the PV modules 131 should be positioned close to the water. The closer the individual PV modules are to the water, the better the efficiency of the PV modules due to the cooling effect of the water. The PV modules 131 can, for example, be mounted on tensioned cables 133 that are attached to the frame 132 of the PV element ( Figure 3). The PV modules can also be self-floating and held in position within the frame, e.g., with ropes. The individual PV modules 131 are secured and / or provided with elastic spacers so that they do not touch each other.

[0069] Not every PV element 130 has to be equipped with an output body; alternatively, it is sufficient if suitable output bodies 135 are only present at certain intervals ( Figure 4, 5). For example, due to low buoyancy and the positional stability of each individual PV element 130 and the connection of the PV elements to one another to form a module field 120 (structure B), the module field can also be lowered into the submerged position by a few drive bodies. The generated controllable drive acts on the positions of the drive bodies 135 and is distributed over the entire module field 120 via the connections 121 (e.g. cables) of the PV elements 130. For example, a square module field 120 of a PV unit 100, consisting of e.g. 100 PV elements 130 (side lengths consisting of 10 PV elements each), can be moved into the submerged position by nine drive bodies 135. The drive bodies 135 can be positioned, for example, at the corners of the square, in the middle of the long sides and in the center of the square. During the descent, the drive bodies, which are connected, for example, toThe PV elements 130 connected by cables 121 form a slightly upwardly curved shape due to their buoyancy, with the lowest points of the curvatures being the positions of the downforce of the downforce bodies 135. The module field 120 has a tendency to contract horizontally here. This curvature is to be limited by suitably weak buoyancy of the individual PV elements and suitably weak downforce of the downforce bodies so that the horizontal connecting forces at the mechanical couplings between the positioning structure 110 (structure A) and the module field 120 remain low. Furthermore, as already described, the field holder can be designed so stable through its edge structure (in particular through outwardly projecting connections to the waterbed) that it compensates for the tendency of the module field to contract and retains its shape regardless of the vertical position of the module field.

[0070] The connections between structure A (field holder 110) and structure B (module field 120) are preferably created with specific mechanical couplings which, in the working position, only prevent the movement of structure B relative to structure A in the horizontal direction. In the diving position, a further degree of freedom, the movement in the vertical direction, is limited downwards by structure A as previously described. Technically, these mechanical couplings can be implemented, for example, using suitable linear guides. For example, rope loops or, for example, elastic or rigid rings with suitable play can move up and down in a horizontal plane around essentially straight vertical structures. Vertical structures can be implemented, for example, the position buoys 111 of structure A themselves, or linear structures attached to the position buoys and running vertically (e.g., rods, taut ropes, guides, etc.).This allows the module array 120 to follow the wave motions to which it is exposed in the vertical direction until it reaches its maximum operating wave height. The described mechanical couplings can also be installed on offshore wind turbines, fish farm structures, drilling platforms, and any other suitable structures.

[0071] In the submerged position, boundaries 115 define the sinking depth of the module array 120. The boundaries 115 can be, for example, thicker bodies (spheres, rods, supports, stop surfaces, etc., see figures), over which a guide eye of the module array or, for example, a running unit 111d (see below) cannot slip. The described connecting elements between structure A and structure B rest on the boundaries and, in the submerged position, transfer the weight forces of the module array 120 of structure B into structure A (array holder 110). The position buoys 111 of structure A now absorb the additional weight through structure B.

[0072] In principle, structure A of a PV unit 100 must, among other things, have sufficient positional stability so that it holds structure B, the module field, sufficiently in position and provides a sufficiently stable vertical boundary for structure B in the submerged position. For this purpose, the alignment of the traction means 112, which connect the weights 113 on the seabed / or other suitable fixed points, e.g., to the position buoys 111 of structure A, must be designed such that structure A forms a field which can guide or position structure B in the manner described. For this purpose, for example, the weights 113 can be positioned at a suitable horizontal distance around the field formed by structure A on the seabed so that traction forces in the traction means only cause vertical forces to an extent that can be compensated for by the position buoys 111 through their buoyancy.Traction devices can also be attached to position buoys 111 inside and on the long sides of the formed field in order to strengthen the connection to the ground or the weights 113 on the ground / or suitable fixed points.

[0073] As from Figure 1 As can be seen, the weights 113 for coupling to the ground are positioned radially outward in all directions from a vertical projection of the surface of the module field 120 onto the seabed.

[0074] The upper end of the position buoys 111, which is located on the water surface, can also optionally be coupled to the water bottom via traction devices ( Figures 13 , 14 , 16 ). In this way, a radial outward pull can prevent the module field from contracting (reducing the area). Such traction devices are preferably provided via deflection buoys (117, 118) floating on the water surface. Figure 16) in order to ensure that essentially only horizontal forces act on the position buoys.

[0075] Overall, the forces acting on the PV unit 100 due to wind, waves, and other currents must be minimized. This is achieved by ensuring that the components of the PV unit offer the smallest possible surface area for the currents to act on. This can be achieved, for example, by using traction devices such as cables. The entire PV unit is therefore permeable to currents and offers only minimal resistance to waves and currents. Furthermore, the entire system is preferably flexible and can deform elastically. This allows it to yield to point-like forces (e.g., breaking waves), thus keeping the loads on the system low. The PV elements 130 can be formed from solid structures in the manner described. The problem of larger surface areas of the PV modules 131 on the PV elements 130, and thus of the PV elements, is solved by allowing the module array 120 to be lowered into the submerged position in the manner described.

[0076] In general, the buoyancy of the buoyancy bodies used (e.g. position buoys 111) should be as large as necessary (for safe positioning of the PV unit) and as small as possible (to minimize the impact of forces acting on the system, including those caused by waves).

[0077] To minimize flow forces on the positioning buoys 111, they can have an optimized shape with a specific buoyancy geometry. For example, a positioning buoy can have an elongated cylindrical shape (optionally with variable diameters along the vertical axis of the buoy), in the lower part of which a suitably dimensioned weight can be located. However, tipping stability can also be achieved by attaching fixing devices to the lower and / or upper part of the buoy. This provides the positioning buoys with high tipping stability and thus enables good horizontal positioning stability for structure B, the module field.

[0078] Furthermore, it is advantageous if the positioning buoys 111 have the smallest possible change in buoyancy when the immersion depth changes. This can be achieved, for example, by a slender shape (e.g., a tube) of the buoy, at least in the area exposed to the wave. Thus, when a wave passes, for example, the tensile forces on the traction devices that hold the buoy in position will increase only to a tolerably small extent, and the entire structure remains relatively stationary.

[0079] A further advantage of a suitable buoyancy geometry, e.g., an elongated cylindrical buoy shape, is that the lower parts of the buoy are already in a calm water layer, thus dampening the movement of the entire position buoy. The position buoys can also be completely submerged in water in very high waves. Other buoyancy geometries are also conceivable, such as spherical buoys linked together by traction devices, which can be arranged in a chain. Furthermore, additional buoys (e.g., stabilization buoys 116, Figures 6 , 16 ) are positioned so deep under water that they are unaffected (or only suitably slightly affected) by the dynamic forces caused by the wave movement, ensuring uniform buoyancy and, in conjunction with the position buoys, can support the formation of structure A as described.

[0080] The following are based on the Figures 7 to 12preferred embodiments of the position buoys 111 are explained in more detail.

[0081] The wave motion creates frictional and pressure forces on the buoy, as well as inertial forces. These are proportional to the displaced water volume and the water acceleration, and are directed in the direction of the water acceleration.

[0082] The cylindrical position buoy 111 with vertical extension described here is hereinafter referred to as "long cylinder buoy" ( Fig. 7). It essentially consists of a cylindrical hollow buoy tube 111a, at the base of which a weight 111b is arranged. The ratio of diameter to total length of the buoy (length of the buoy tube 111a + length of the weight 111b) is preferably less than 1:2, particularly preferably less than 1:10. The smaller the ratio of diameter to total length and the greater the total length, the smaller the change in buoyancy due to the wave motion on the surface. As a result, the vertical movement of the position buoy 111 is smaller compared to the wave motion.

[0083] To further dampen the upward and downward movements of the long cylindrical buoy 111, a vertical drag, e.g., in the form of a (horizontally extending) round plate, can be attached to the lower end of the weight 111b as a damping element 111c (several vertical drags stacked on top of each other are also conceivable). During the upward movement, the vertical drag 111c creates a resistance that counteracts the upward movement. Likewise, the vertical drag counteracts the downward movement of the buoy. Overall, the vertical drag acts as a movement-damping element and reliably prevents resonance vibrations of the buoy.

[0084] In order to create favorable flow conditions at the vertical current brake 111c, the vertical current brake can optionally be provided with a hole pattern through which water flows as the buoy 111 moves up and down (due to the waves on the sea surface). There and at the flow edges on the outer radius of the vertical current brake, the water is usually turbulent. The vertical current brake 111c deliberately has a very small extension (thickness) in the vertical direction in order to offer only very little resistance to horizontal currents; in the horizontal direction, however, the extension is large in order to dampen the up and down movement of the long cylindrical buoy 111. The horizontal currents for which the resistance is minimized by the selected shape include tidal currents and local or regional currents.

[0085] The long cylinder buoy 111 is designed to minimize movement of the buoy near the sea surface. This is achieved through the following measures: 1) The above-mentioned pressure, friction, and inertia forces are minimized or optimized in the horizontal direction across the entire length of the buoy. The optional selection of a round cross-section creates equal conditions for pressure and friction forces from all flow directions. A reduction in the diameter of the cylindrical buoy 111 in the upper water layers is also conceivable, in order to further minimize the area exposed to pressure and friction resistance, as well as the displaced volume to reduce inertia forces. The vertical flow brake 111c in the lower area has a minimal volume and thus minimal inertia forces (assuming these are still practically relevant in the lower water layers). In addition, its horizontal orientation minimizes the area exposed to horizontal currents. 2) Minimization of resistance in the vertical direction in the upper area of ​​the buoy, i.e.In the area of ​​relevant wave motion, through a smooth geometry and surface without discontinuous steps, edges, and protruding functional components. 3) Maximizing vertical resistance in the lower part of the buoy, i.e., in the area of ​​water layers virtually unaffected by wave motion, e.g., through the described current brake or multiple current brakes.

[0086] Horizontally acting damping elements 111e ( Figure 9 ) in the lower area of ​​the long cylinder buoy 111, which essentially clamp the long cylinder buoy in the virtually motionless lower water layers. Horizontally acting damping elements can be advantageous when there are no significant horizontal currents. In addition, the horizontally acting damping elements also dampen the rotation of the long cylinder buoy around its vertical axis.

[0087] Due to the design of the long cylinder buoy 111 (weight 111b in the lowest area, buoyancy provided by the buoy tube 111a always above the weight), the long cylinder buoy always develops restoring forces when deflected by external forces. As soon as it is tilted from the vertical by horizontal forces in the upper, wave-influenced area, such as horizontal forces from the connected PV array, it develops a restoring moment, or a horizontal restoring force. Even in the vertical direction, the long cylinder buoy always strives for a balance between buoyancy and weight forces.

[0088] If the inherent alignment forces of the cylinder buoy 111 are not sufficient (e.g. along the edge of a PV unit), an essentially horizontal pulling device can be attached to the upper end, which can be connected, for example, to deflection buoys floating on the surface (117 in Figure 16 ) is connected to the water bed.

[0089] The coupling of the module field 120 to the field holder 110 can be effected in particular on the long cylinder buoy 111. In the embodiment of Figure 7 and 8The coupling is achieved, for example, via a running unit 111d, which is fixedly guided horizontally relative to the long cylindrical buoy and movable vertically. The running unit 111d can, in particular, also be designed as a downforce body (with fixed or variable downforce), i.e., have a sinking tendency. Alternatively, the running unit 111d can be designed as a buoyancy body (with fixed or variable buoyancy) or can be adjustable between buoyancy and downforce. The running unit 111d can, for example, have the shape of a hollow cylinder that surrounds the cylindrical buoy tube 111a with some play. Preferably, the rotational mobility of the running unit 111d about the vertical axis of the buoy tube 111a is eliminated or at least restricted (for example, via restoring forces).

[0090] The connection of the module field 120 to connection points of the running unit 111d (e.g. the Figure 7The connection (visible eyelets) can be fixed, bendable, rotatable, and / or flexible. A flexible connection reduces deformation and stress on the components at the edge of the 120 module array.

[0091] Furthermore, the long cylinder buoy 111 preferably has mechanical stops at the upper (not shown) and lower ends of the movement path of the running unit 111d.

[0092] The horizontal module array 120 is connected, for example, via the running unit 111d. As a result, the force flow in the horizontal direction typically passes uninterrupted through the array holder 110 and the module array 120 (with the possible exception of edge areas). Movement of the running unit 111d is possible in the vertical direction. The vertical coupling of the array holder and the module array by means of the running unit 111d is preferably designed to be controllable, so that the axial forces (in the direction of the buoy's longitudinal axis) can be adjusted (permanently in advance through design measures and / or dynamically during operation).

[0093] The running unit 111d thus serves to couple horizontal and vertical forces between the field holder 110 and the module field 120, in the horizontal direction with a complete transmission of the force flow of the horizontal forces, in the vertical direction preferably with variable, adjustable properties.

[0094] This adjustability is achieved, for example, via 1) mechanical components (positive-locking pairing of gears / racks, ball bearings, roller bearings, pressure rollers, etc.), 2) hydraulic components (pressure cushions, hydraulic cylinders that press slide rails against the running surfaces in a defined manner, etc.), 3) electrical components (linear motor, magnetic, inductive, etc.) and / or 4) realized by varying the buoyancy force of the running unit 111d.

[0095] The adjustability, in particular, allows the mobility of the module array relative to the array holder to be varied. In particular, the adjustability allows the vertical positioning to be varied from virtually resistance-free movement to complete locking.

[0096] The free vertical mobility can be realized, for example, in normal operating conditions when the module field is operating on the sea surface. Figure 8In this context, a central axial section through the running unit 111d is shown. It can be seen that the running unit is in contact with the cylinder buoy via (e.g., twelve) rotatable guide rollers. By controlling the rotatability of these guide rollers, the mobility of the running unit 111d can be varied.

[0097] Furthermore, by reducing the buoyancy force while allowing free movement, the running unit 111d can be lowered with the module array 120 into one of the previously described positions (diving position, etc.). There, for example, the running unit 111d can then be locked by securing the guide rollers.

[0098] A significant additional advantage of the adjustable coupling forces in the vertical coupling direction is that the hydroelastic behavior of the horizontal module array 120 can also be influenced. By appropriately adjusting the mobility, the wave parameters of the waves moving through the module array can be influenced. This results in a dissipation of wave energy when the up-and-down movement of the running unit 111d is slowed by the wave motion due to the adjusted coupling forces. With the variable force control in the vertical direction on a long cylinder buoy, the hydroelastic behavior of several module arrays can also be influenced if the long cylinder buoy is coupled to the module arrays accordingly at the same time. Additional long cylinder buoys within a horizontal module array can also be imagined as vertical guides.When several module fields placed close to each other together form a larger, contiguous horizontal PV area (PV power plant 1000, . Figures 13 to 16 ), a suitable number of long cylindrical buoys are thus located within the entire area, which, by controlling the vertical coupling force at each long cylindrical buoy, enable the hydroelastic behavior of the entire area to be optimized. By appropriately adjusting vertical coupling forces, wave movements can be dampened and thus significantly reduced within the module arrays. The mobility (coupling strength) can be the same for all cylindrical buoys or individually adjusted for each cylindrical buoy. In particular, different coupling conditions may exist at the edge of the PV power plant or PV unit than in the interior areas.

[0099] The described long cylinder buoy enables the guided lowering of module fields into, for example, the protective position with simultaneous return action.

[0100] Optionally, the long cylinder buoys 111 can also be designed to be lowered with the module array 120. If the cylinder buoy is sufficiently long (e.g., in the operating position, it protrudes from the water by the stroke of the module array), a part of it always remains above the water surface in the lowered position, while the array holder retains its structure or shape. The horizontal positioning of the entire system can be taken over by appropriate auxiliary buoys (e.g., the stabilizing buoys 116, deflection buoys 117). In this case, the coupling of the buoy holder 111h and the buoy tube 111a is freely movable in the upper and lower areas in the vertical direction ( Figures 11 , 12 ). The locking of the locking unit 111j is then released in the upper and lower areas.

[0101] In the Figure 9 Two alternative designs of a long cylindrical buoy 111 are shown. As with the previous embodiment, this contains a buoy tube 111a with a weight 111b attached to the bottom, as well as vertically acting and horizontally acting damping elements 111c, 111e. The example shown on the left shows three horizontally acting damping elements 111e, which are distributed unevenly around the circumference (running vertically), while the example shown on the right has four horizontally acting damping elements 111e distributed evenly around the circumference. Of course, other numbers of horizontally acting and vertically acting damping elements with different distribution and geometry can also be provided.

[0102] According to Figure 10The coupling of a module field is realized via a running unit 111f with an eyelet for connecting the module field, whereby the running unit 111f is guided in a vertical linear guide 111g (undercut rail) on the surface of the buoy tube 111a. In Figure 10 In the example shown on the left, only one linear guide 111g is provided, while the example shown on the right has four linear guides 111g evenly distributed over the circumference, each with a running unit 111f.

[0103] The guided movement of a running unit along a cylinder buoy 111 or another guide element can also be realized as a forced guide by means of chains, racks, positive gears or the like.

[0104] Figure 11shows another optional design for the base area of ​​a cylinder buoy 111. The lower stop position 115 for the running unit 111d is designed to exhibit a specific dynamic behavior, namely that of a buffer with damping and spring properties. Specifically, a stop plate 111k is provided for contact with the running unit 111d, which is connected to the buoy holder 111h and the locking unit 111j via damping elements 111m (shock absorbers with pistons and cylinders) and parallel coil springs 111n. Traction devices (not shown) for anchoring the cylinder buoy 111 to the waterbed can be coupled to the buoy holder 111h.The locking unit 111j serves to fix the stop position 115 at a selectable axial position of the buoy tube 111a. This fixation can occur during the erection of the PV unit (and then remains essentially unchanged) or dynamically during operation of the PV unit. The impact of the running unit 111d during the lowering of the coupled module array (not shown) can thus occur in a dynamically optimized manner, for example, to avoid critical force loads and / or the generation of vibrations.

[0105] In the upper part of the buoy ( Figure 12 ), the upper stop position can be designed in the same way. The upper buoy holder 111h is located above the running unit 111d, and the lower buoy holder 111h is located below the running unit 111d. The damping elements are located between the buoy holder 111h and the running unit 111d.

[0106] If the locking units 111j and thus the buoy holders 111h are adjusted to be movable relative to the buoy tube, the entire long cylindrical buoy 111 with the module array 120 can be lowered. The buoy holders 111h are held in position, for example, by their own buoyancy and / or by suitable stabilizing buoys 116 and attachment means such as ropes in the lower area. In the upper area, the buoy holder 111h itself can be held in position by its buoyancy on the water surface and / or by stabilizing buoys and / or deflection buoys 117 with suitable attachment means such as ropes.

[0107] When the locking units 111j and thus the buoy holders 111h are locked, the module field 120 can be moved vertically guided on the long cylinder buoys 111 by means of the movement of the running units 111d.

[0108] Figure 12shows the optional design of the upper end section of a cylindrical buoy 111. The buoy holder 111h, in conjunction with the locking unit 111j, forms the upper stop position. The upper stop position 115 for the running unit 111d is designed with the aid of one or more stop buffers (e.g., made of rubber or a similar elastic material, springs, hydraulic buffers, etc.) to exhibit a specific dynamic behavior (damping and elasticity).

[0109] The Figures 11 and 12 The stop positions (end stops) shown can be used as both the lower and upper stop positions, regardless of the specific representation in the example drawings.

[0110] When the end stop in the end bearing is reached, the force acting there simultaneously causes a yielding / subsequent movement of the cylinder buoy in the direction of the force, so that the end stop is further dampened here.

[0111] In Figure 13 A PV power plant 1000 is schematically shown, which is constructed from a plurality of PV units 100 of the type described above, which are coupled to one another via their side surfaces. In Figure 14 This power plant 1000 is shown without PV modules (or with transparent PV modules) and without PV elements. Figure 15 shows a top view and Figure 16 a side view of this power plant 1000.

[0112] The electrical energy generated by the power plant 1000 can, for example, be transmitted to land via electrical cables not shown in detail, it can be stored on site (e.g., through the production of "green hydrogen"), or it can be used for other purposes.

[0113] As explained above, the individual PV units 100 of the power plant consist of module arrays 120, which can be moved along the positioning buoys 111 of a field holder 110 between an operating position and (at least) one submerged position. The edge-positioned positioning buoys 111 are connected at their lower ends via traction means 112a to anchor points 113 on the waterbed, with these traction means projecting outward in the edge region (pointing away from the surface of the module arrays). In the illustrated embodiment, positioning buoys located inside the power plant 1000 are only coupled to the horizontal bracing of the field holder 110 (internal traction means 114) at the level of the deepest submerged position. Additionally or alternatively, they could also be connected directly to the waterbed.

[0114] In the example shown, the position buoys 111 are also coupled at their upper end to anchor points 113 on the water bottom via traction means 112c in the edge areas, whereby these traction means 112c are guided over deflection buoys 117 floating on the water surface (outside the area of ​​the PV modules) so that the corresponding tensile forces act horizontally on the position buoys 111. The deflection buoys 117 can optionally be connected to the power plant via a cable structure and / or a frame-like rod system made of, for example, elastic tubes or the like (outer frame 118, Figure 15 ) be coupled together.

[0115] The traction means 112a, 112c acting on the position buoys 111 extend outwards from the surface formed by the PV modules, preferably obliquely at an angle of at least 10°, particularly preferably at least 20°, at least 30°, at least 45°, or at least 60° to the vertical.

[0116] At the level of the (deepest) diving position, the field holder 110 can have substantially horizontally extending internal traction means 114, which can be coupled to the water bottom via separate traction means 112b.

[0117] As shown, two or more of the traction means 112a, 112b and / or 112c can be coupled to a common anchor point (weight 113) on the water bottom.

[0118] Optional breakwater elements can be integrated very cost-effectively into the edge structure of a 100-meter PV unit or a 1000-meter PV power plant close to the surface (not shown). In conjunction with the lowering of the module array when certain critical wave parameters are exceeded, these elements can replace traditional, very cost-intensive breakwaters with large vertical extensions. This configuration enables the safe and economical implementation of PV power plants under offshore conditions.

[0119] With the described components, it is possible to optimize the entire PV unit 100 and a PV power plant 1000 in such a way that the position of the PV unit is securely maintained, but wave movements vary the buoyancy as little as possible, and the smallest possible forces are introduced into the structure of the PV unit, thus minimizing loads. A PV power plant, compared to other floating structures of the same size, has a very low dead weight and, by its very nature, also low system costs.

[0120] PV units 100 may consist of rectangular or square PV elements 130 and may have a rectangular or square dimension. PV elements 130 may also have any other shapes such as hexagons ( Figure 6 ) or generally have polygonal or round shapes, and from their totality form PV units 100 of any size.

[0121] A PV unit 100 of the type described offers the following advantages during construction and installation: The transport of components, buoys and ropes, buoyancy devices, and other components is possible using conventional means of transport (sea transport, truck, train, etc.). Almost all components can be prefabricated or built, allowing for quick and systematic assembly of the PV unit and even the replacement of defective components using a modular approach. List of reference symbols

[0122] 100PV unit 1000PV power plant 110Field holder ("Structure A") 111Position buoy, long cylinder buoy 111aBuoy tube 111bWeight 111cVertically acting damping element, vertical flow brake 111hHorizontally acting damping element 111d, fRunning unit 111gLinear guide 111hBuoy holder 111jLocking unit 111kStop plate 111mShock absorber 111nSpring elements 112, 112a, b, cTension means to the fixing point 113Weight 114Internal tension means 115Vertical boundaries 116Stabilization buoy 117Deflection buoy 118External frame, edge structure 120Module field ("Structure B") 121Connections between PV elements 130PV element 131PV module 132Frame 133Holding cable 135Output body GBWaterbed or terrestrial soil GOWater surface STProtection depth LUAir WAWater GGeight

Claims

1. Photovoltaic unit (100) for waters, comprising - a module array (120) with at least one PV module (131); - an array holder (110) configured to displace the module array (120) between an operating position on the surface of the water (GO) and a submerged position (ST) below the surface of the water (GO); wherein - the array holder (110) has fixing means (111, 113) for coupling to the ground (GB) and / or to the water surface (GO); and - the module array (120) is movable in one direction relative to the array holder (110); characterized in that the array holder (110) has at least one substantially vertically extending guide element (111), to which the module array (120) is movably coupled, and / or the mobility of the module array (120) relative to the array holder (110) is variable.

2. Photovoltaic unit (100) according to claim 1, characterized in that the module array (120) is movable relative to the array holder (110) up to at least one stop position (115).

3. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that the module array (120) and / or the array holder (110) contains - at least one buoyancy body (111, 116, 117) and / or - at least one sinking body (135) with variable downforce or is coupled thereto.

4. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that the guide element (111) comprises a movably mounted running unit (111d, 111f) to which the module array (120) is connected or can be connected.

5. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that it comprises a buoyancy body (111) which has an elongated shape, the ratio of width to length preferably being 1:2 or less.

6. Photovoltaic unit (100) according to claim 5, characterized in that the buoyant body (111) is configured to assume a substantially vertical orientation in water.

7. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that the module array (120) is movable along a buoyancy body (111).

8. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that it comprises a buoyancy body (111) with at least one damping element (111c, 111e) for damping its movement in water.

9. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that it comprises at least one buoyancy body (116) which is configured to assume a position below the water surface (GO) in the operating state, this position preferably being at the submerged position (ST) or below.

10. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that at least one fixing means (111, 113, 117) for direct and / or indirect coupling to the ground and / or to the water surface (GO) is located outside the area of the module array (120) when seen in the vertical direction.

11. Photovoltaic unit (100) according to at least one of the preceding claims, characterized in that it is configured to carry out a method according to claim 12 and / or 13.

12. Method for operating a photovoltaic unit (100) according to claims 1 to 11, comprising a module array (120) with at least one photovoltaic module (131) on a body of water, characterized in that the module array (120) is displaced depending on the situation - for cleaning purposes; - and / or for interrupting or reducing electricity production - and / or when solar radiation is low; - and / or when solar radiation is below a predefined minimum value; - and / or at night; - and / or for safety reasons; - and / or for cooling purposes; - and / or for maintenance purposes; - and / or for traffic reasons; between an operating position on the surface of the water (GO) and a submerged position (ST) below the surface of the water (GO).

13. Method for operating a photovoltaic unit (100) according to at least one of claims 1 to 11, characterized in that the module array (120) is displaced between an operating position on the surface of the water (GO) and a submerged position (ST) below the surface of the water (GO) depending on the situation in the event of waves and / or storms above a given level.

14. Module array (120) for a photovoltaic unit (100) according to at least one of claims 1 to 11.

15. Array holder (110) for a photovoltaic unit (100) according to at least one of claims 1 to 11.