MODULE MOUNTING AND ASSOCIATED PHOTOVOLTAIC SYSTEM

Description

[0001] The invention relates to a module holder and associated bifacial photovoltaic (PV) module, which together can be considered a (mounting) set. The photovoltaic module is designed as a frameless laminate and has an active surface that can receive sunlight from both the front and back of the module to convert it into electricity. The module holder provides a recess into which an outer edge of the photovoltaic module is inserted and thus held in position. This recess, relative to a plane of the active surface of the photovoltaic module, is bounded at the front by a front leg and / or at the rear by a rear leg of the module holder.

[0002] Such module mounting systems are already known; however, they have so far mainly been used for monofacial PV modules, which are positioned so that they can essentially only receive sunlight from one side.

[0003] The invention further relates to a photovoltaic system with several such bifacial PV modules, each designed as a frameless laminate and arranged upright (i.e., in a vertical orientation) on a support structure. The support structure comprises several posts that are attached to or embedded in the ground, in particular anchored, with crossbars attached to the posts, each connecting two adjacent posts to one another (directly or via adapter elements). These crossbars thus run essentially horizontally, while the posts run vertically. The module holder is provided for securely holding the PV module. The module holder can be attached to a crossbar and / or a post of a support structure of the PV system.In other words, the module holder can serve to attach the associated bifacial PV module to the supporting structure, in particular to at least one beam and / or at least one post of the supporting structure.

[0004] Such PV systems are already in use for generating solar power. In these systems, the module plane, i.e., the plane in which the active surfaces of the PV modules are located, is often oriented in a north-south direction. This has the advantage that the PV modules can capture the low-angled sunlight from easterly directions on their front side in the early morning hours. In the evening hours, when the sunlight is low-angled from westerly directions, the bifacially designed PV modules can capture the sunlight on their back side. This results in a current curve for the solar power generated by the PV system that shows a maximum before and after midday. The higher the sun is above the horizon, the steeper the angle of incidence of the sun's rays (relative to the Earth's surface) becomes as they strike the front or back of the respective PV module.

[0005] There is currently a trend towards installing increasingly larger PV modules, for example, those exceeding two square meters. With existing support structures based on posts connected by crossbeams, such large-area PV modules present the problem that the individual modules can deflect so much under wind load that they can no longer be securely held by the crossbeams. Another ongoing trend is the continuous improvement of solar power production efficiency, as the generation of electricity from renewable energy sources becomes increasingly valuable.

[0006] A bifacial PV module with a frame is known from CN 206850713 U, the frame of which is attached to a supporting structure by means of C-shaped retaining elements. The retaining elements engage with the frame of the PV module, which in turn frames and encloses the laminate of the PV module.

[0007] DE 10 2016 015 436 A1 describes a supporting structure consisting of vertical posts and horizontally extending beams, designed to support bifacial, upright PV modules. To prevent shading of the PV modules, it is proposed to chamfer the undersides of the horizontally extending beams, which are designed as longitudinal profiles, and, if necessary, to insert the PV modules directly into corresponding mounting grooves in the beams.

[0008] Against this background, the invention aims to make a technical contribution to both of the problems described. The invention is intended to provide a support structure that can reliably withstand high wind loads, even with very large module sizes, while simultaneously enabling high electrical efficiency of the PV system. This is achieved by providing a (mounting) set, as described above, which can be integrated into the support structure to arrange the PV modules within it.

[0009] To solve this problem, the invention provides the features of claim 1 for a set consisting of a module holder and an associated bifacially designed PV module. In particular, the invention proposes that, to solve the problem in a set of the type mentioned above, the respective front and rear outer points of a cross-section of the module holder extending perpendicular to a plane of the active area are set back in the insertion direction and with respect to the respective module-side tips of the two legs. Here, said outer points are those outer points of the cross-section of the module holder that are relevant for shading of the active area caused by the module holder.

[0010] The axial offset of these outer points along the insertion direction to the respective tip of the front or rear leg can preferably be at least 1.2 times, preferably at least 1.5 times, or even at least 2.0 times, a minimum width of the receptacle. For example, in a module holder according to the invention with a minimum width (or insertion width) of 5 mm (this corresponds to a maximum thickness of the PV module at the edge that can still be inserted into the receptacle), the axial offset of the outer points can be 11 mm, i.e., 1 1 / 5 = 2.2 times the minimum width of the receptacle.

[0011] In such configurations, an envelope relevant to the shading of the active area by the module mount, and which encloses an outer contour of the module mount, can exhibit a convex shape when viewed in the direction of installation. In other words, the lateral width of the envelope, perpendicular to a plane of the active area, increases monotonically in the installation direction. The envelope of the module mount thus exhibits its smallest lateral width on the module side. Put another way, the envelope of the module mount tapers monotonically towards the PV module – contrary to the installation direction – both from the front and the back of the PV module. The shape of the envelope could be determined, for example, by mentally or physically placing a cloth or film over the module mount from the installation direction and stretching it in that direction.The envelope can thus define the contour relevant for shading the active area, which limits the possible angles of incidence of sunlight onto the active area.

[0012] Such designs minimize the shading effect of the module mounting on the active area of ​​the bifacial PV module. In particular, this allows for shading-free conditions on the active area up to a maximum lateral or vertical angle of incidence of at least 110°, both on the front and back of the PV module. Simultaneously, the module mounting can be designed with high mechanical strength, thus stabilizing the unstable PV module, especially when subjected to high wind loads.

[0013] However, many of the module frames currently available on the market, when used to hold bifacial PV modules, lead to shading of the active areas on the back of the module, so that, especially at a shallow angle of incidence on the PV module, the shadow resulting from the module frame significantly reduces solar power production.

[0014] To reduce the susceptibility of the active area to shading when the maximum shading-free angle of incidence is exceeded, it is also advantageous if the respective lateral distances between the outer points and the plane of the active area differ by less than 25%, preferably by less than 15%. This allows for a module mounting cross-section in which the respective lateral distance between the module plane and the mounting (often referred to as the lateral cell plane-frame distance) is minimized. This is advantageous because the smaller the lateral distance between the module plane and the mounting, the smaller the shading length of the active area (measured in the plane of the active area) will be (depending on the angle of incidence of sunlight) when the maximum shading-free angle of incidence is exceeded.This significantly reduces the set's susceptibility to shading.

[0015] Such designs make it possible in particular to ensure that the maximum angles of incidence without shading (at which sunlight can reach the active surface from the front or the back), measured with respect to the active surface, are at least 120°, preferably even at least 135°.

[0016] A module holder according to the invention can be designed to be, for example, more than three times longer in the insertion direction and in the direction perpendicular to a surface normal of the active surface (i.e., in a direction along the outer edge of the PV module) than the depth of the module holder in the insertion direction. This allows the receptacle to take the form of an elongated slot. The receptacle itself can be designed to be at least 1.5 times or even at least 2.0 times as deep in the insertion direction as a minimum width of the receptacle in the direction of a surface normal of the active surface. This ensures a secure grip on the outer edge of the PV module.

[0017] It should also be mentioned here that a module holder according to the invention can also be designed in two parts. In this case, a front part of the module holder can form the front leg of the receptacle, and a rear part of the module holder can form the rear leg. The two parts can overlap along the outer edge of the PV module (in which case the PV module is held on both sides at least in the overlap area) or be spaced apart from each other (in which case the outer edge of the PV module is held section by section at the front and section by section at the rear by the module holder). However, embodiments in which the respective module holder is designed in one piece and forms both a front and a rear leg of the receptacle are preferred.

[0018] Furthermore, a module holder according to the invention can also form two opposing receptacles, namely when the module holder is designed to directly connect two adjacent PV modules. In this case, a PV module is inserted into each of the two receptacles.

[0019] The ratio between the maximum width of the module holder in the direction of insertion and the maximum insertion depth of the mount can, for example, take values ​​between 1.20 and 2.80. The distance between the outer edge of the PV module and a stop inside the mount, formed by the module holder, can be, for example, 1-2 mm.

[0020] The module holder can also be used to stabilize a longitudinal or transverse side of the PV module, either partially or completely. Depending on the design, the length of the holder can thus extend transversely to the insertion direction over the entire length of a longitudinal or transverse side of the PV module. In this case, the module holder therefore encompasses the entire longitudinal or transverse side of the PV module.

[0021] As mentioned, each PV module held by its respective module holder is designed as a frameless laminate; in particular, it can be a glass laminate. The active surface can be integrated into the laminate. For example, the active surface may only be covered by a film on one side.

[0022] Furthermore, the active area can be arranged offset from a central plane of the PV module. This can result in different maximum unshaded angles of incidence, even with a symmetrical design of the module holder and central placement of the PV module in the holder's receptacle, at which sunlight can still reach the outer edge of the active area when the PV module is inserted into the holder's receptacle.

[0023] Furthermore, the PV module can also have more than one active surface. The "bifacial" property can therefore be understood here to mean that the PV module has at least one active surface (i.e., two or even three active surfaces) that can each convert sunlight into an electric current / voltage. If the PV module has multiple active surfaces, these can also differ in their respective spectral characteristics, specifically so that each surface converts a different light spectrum into electrical energy. The multiple active surfaces can be laminated together, meaning they are spaced apart from each other in a direction perpendicular to the respective plane of the active surface.

[0024] The inventive approach can preferably provide that the active surface of the PV module is arranged approximately centrally with respect to the outer dimensions of the module holder. For example, embodiments are preferred in which the lateral distance between a plane of the active surface and a median plane of the module holder is at most 10% of the total lateral extent of the module holder. In particular, the plane of the active surface and the median plane of the module holder can thus coincide.

[0025] Alternatively or additionally to the features described above, the set mentioned at the outset can also be characterized in such a way that an outer contour of the module holder (i.e., in particular the aforementioned outer contour or the aforementioned envelope), with respect to a cross-sectional plane of the module holder extending perpendicular to a plane of the active surface, lies within a shading angle spanned in the cross-sectional plane, which originates from an outer edge of the active surface. Furthermore, it is provided that an angle bisector of the shading angle with the plane of the active surface forms a tilt angle of at most 15°, preferably at most 10°. The shading angle defines the shading of the active surface caused by the module holder.

[0026] If the active surface lies, for example, in an xz-plane (where the x-direction can correspond to a longitudinal direction of the beams and the z-direction to the longitudinal direction of posts of an associated supporting structure to which the module holder is to be mounted), then the said cross-sectional plane can be the xy-plane in the case that the module holder encompasses a vertically extending transverse side of the PV module; or, for example, the yz-plane in the case that the module holder encompasses a horizontally extending longitudinal side of the PV module.

[0027] Limiting the tilt angle results in a balanced distribution of the maximum unshaded angles of incidence between the front and back of the PV module. This allows for high solar power production efficiency with the bifacial PV module, regardless of the direction of sunlight incidence. The requirement for a small tilt angle is therefore equivalent to the requirement that the active surface of the PV module should be positioned as close as possible to a central plane of the module mounting (which can be a plane of symmetry).

[0028] Another parameter to consider when designing the system is the offset between an outer edge of the active area and the module-side end of the mounting bracket when the PV module is inserted. This presents a fundamental trade-off: the larger the offset, the smaller the shading angle, which initially seems advantageous as it reduces susceptibility to shading. However, a larger offset leads to a loss of active area and thus lower power output for a given module size and insertion depth into the mounting bracket. The maximum (glass) size of the PV module is typically limited by the manufacturing technology. A typical current value for the cell edge distance, i.e., the distance between the outer edge of the active area and the outer edge of the PV module, is 18–20 mm.In the future, smaller cell edge distances of 12-14 mm will also be possible, meaning that with the same module size, more active area will be available. However, with such a small cell edge distance, the aforementioned offset would become increasingly smaller, leading to more shading.

[0029] In such a case, the inventive design of the module holder becomes increasingly important because it prevents excessive shading. Therefore, the invention specifically proposes selecting an insertion depth of the receptacle (particularly considering a minimum distance of 1-2 mm between an outer edge of the PV module and a stop formed in the receptacle by the module holder) such that the aforementioned offset between the outer edge of the active area and the module-side end of the module holder does not restrict the desired maximum unshaded angles of incidence (i.e., still allows the desired respective maximum unshaded angles of incidence on the front and rear sides), which will be explained in more detail below.The offset can preferably be chosen to be no more than 50%, preferably no more than 20%, larger than a minimum offset that must be maintained (purely geometrically and without considering tolerances when inserting the PV module into the module holder) to ensure the desired maximum unshaded angle of incidence. This allows for a compact design of the set, optimizing the usable active area per unit length / height of the associated PV system.

[0030] The previously described shading angle can ideally be symmetrically open to a central plane of the PV module (so that the central plane bisects the shading angle). However, depending on the specific design of the module mounting and / or the lateral position of the active surface, it is also possible for the shading angle to be asymmetrically open with respect to the central plane of the module; in this case, the aforementioned tilt angle is therefore greater than 0° in magnitude (the tilt can be directed towards the front or back). This can be the case, in particular, if the respective maximum unshaded angles of incidence onto the active surface on the front and back of the PV module are different.

[0031] In preferred embodiments, the shading angle is at most 100° or even at most 90°. This allows for particularly large maximum angles of incidence free from shading. With such a design, 360° - 100° = 260° = 2 x 130° (in the preferred embodiment with a maximum shading angle of 90°, even 270° = 2 x 135°) remain available for the maximum angles of incidence free from shading on the front and rear sides, at which sunlight can still reach the active area when the PV module is inserted into the module holder.

[0032] An excessively small shading angle can result in a module mount with insufficient strength, which is particularly critical when the mount is intended to stabilize a vulnerable longitudinal side of the PV module. Therefore, it is particularly advisable to ensure that the shading angle is at least 50°, preferably at least 60°. Requiring such a minimum shading angle results in a corresponding stiffness of the module mount, as this ensures that the module mount has a sufficient area moment of inertia across its cross-section.

[0033] In addition to or as an alternative to the features described above, the set described at the outset for solving the problem can also be characterized by the fact that an outer contour of the module holder (i.e., in particular the outer contour of the module holder described above) is designed (in particular, and the associated PV module is designed and placed in the holder) such that both a maximum shading-free angle of incidence, at which an incident sunbeam can reach an outer edge of the active area from the front, and a maximum shading-free angle of incidence, at which an incident sunbeam can reach the outer edge of the active area from the back, each measured with respect to the active area, is at least 110°, preferably at least 120°, and particularly preferably at least 135°.

[0034] The choice of a suitable maximum unshaded angle of incidence depends significantly on the geographical location of the PV module and its orientation in relation to the sun.

[0035] If the angle of incidence were measured not with respect to the plane of the active surface, but with respect to the surface normal of the active surface in a cross-sectional plane perpendicular to the plane of the active surface, the corresponding maximum unshaded angles of incidence would be at least 20° (=110°-90°), preferably at least 30° (=120°-90°), and particularly preferably at least 45° (=135°-90°). It is understood that, depending on the position of the sun, i.e., the time of day, the maximum unshaded angles of incidence can be exceeded, resulting in shading at the edge of the active surface that increases non-linearly with increasing angle of incidence, which can lead to a measurable power loss of the PV module.

[0036] As already explained, it is further advantageous if the outer edge of the active area is distanced from the module-side end of the module mounting so far that no shading occurs on the active area, even at the maximum angles of incidence specified by the module mounting. In this case, these maximum angles of incidence can actually reach the entire active area of ​​the PV module.

[0037] According to the invention, the problem can also be solved by further advantageous embodiments according to the dependent claims: For example, it can be provided that the two legs of the module holder each form an outer contour that remains within an imaginary or actual chamfer that converges on a module-side insertion opening of the receptacle. It is preferred if the respective chamfer forms an angle of at least 110°, preferably at least 120°, and particularly preferably at least 135° with respect to the active surface. In this case, the respective outer contour of one of the legs can deviate inwards from the chamfer towards the receptacle at certain points.

[0038] For example, an actual bevel can be formed on both the front and back sides (in relation to the PV module inserted into the mount), on the module side (i.e., on the inside of the module mount). These bevels create the technical effect of enabling the described large maximum shading-free angles of incidence onto the active area, thus largely preventing shading of the active area by the module mount itself.In the installation situation, the respective bevel can, for example, allow a steep incidence of sunlight from above (for example, if the module holder encompasses an upper horizontally running longitudinal side of the PV module and the bevel thus points downwards) or a shallow incidence of sunlight from the side (for example, if the module holder encompasses a vertically running transverse side of the PV module and the bevel thus runs in the direction of the longitudinal side of the PV module, if the PV module is oriented in landscape format (= longitudinal side of the PV module is horizontally oriented)).

[0039] A module holder according to the invention can be designed, in particular, to be symmetrical with respect to a plane of symmetry of the module holder running parallel to the plane of the active surface, i.e., in particular with axially symmetrical legs. This can offer advantages because the module holder can then be used in different orientations to grip and protect the outer edge of the module (no difference between the front and back of the module holder).

[0040] A module mounting according to the invention can also be designed asymmetrically with respect to the plane of the active surface. This is particularly advantageous if the active surface within the PV module is offset from a central plane of the PV module. In this case, a symmetrical design of the module mounting would result in asymmetrical maximum unobstructed angles of incidence for the front and back of the PV module. An asymmetrical design of the module mounting (for example, by forming different chamfers on the front and back and / or by having different lateral extensions of the front and rear legs) can therefore be used to ensure that sunlight can reach the active surface from both the front and the back at the same maximum angles of incidence, for example, at least 110° each.However, an asymmetrical design of the module mounting can also be useful if the maximum possible shading-free angles of incidence are to be designed asymmetrically due to low bifaciality of the PV module (rear side power of the active area differs significantly from the front side power).

[0041] The two legs of the module holder can each have a lateral extension, transverse to a median plane of the PV module and measured from the mounting point, that is at least 25%, preferably at least 50%, and particularly preferably at least 75% of a minimum mounting width in the direction of a surface normal of the active area. Depending on the design, the mounting width can increase in the insertion direction. This allows sufficient mechanical strength to be achieved while simultaneously minimizing shading on the front and back of the PV module.

[0042] The midplane of the PV module may be laterally offset from a midplane of the mount or from a midplane or plane of symmetry of the module holder; this depends on the design of the PV module used.

[0043] If, for example, the PV module has a aspect ratio (longitudinal side / transverse side) of approximately or even greater than 2:1, it is recommended to stabilize the longer longitudinal side of the PV module using a module holder according to the invention, the legs of which each have a lateral extension of more than 0.75 times the minimum width of the mounting (which can correspond at least to the thickness of the PV module). Module holders designed according to the invention can then also be used to stabilize the transverse sides; however, the lateral extension of the legs may be smaller there, because fewer forces act on the transverse side and the module holder can therefore be designed to be somewhat less stable.

[0044] The respective tips of the front and rear legs can be spaced either equidistantly or at different distances from the outer edge of the active area, viewed in a cross-sectional plane perpendicular to a plane of the active area (xy or yz plane). With optimal area utilization, at least one of the tips of the front or rear leg can extend to the edge of the active area. However, the module mounting should never cover the active area to prevent power losses due to shading.

[0045] A module holder according to the invention can have a total extent transverse to a central plane of the photovoltaic module that is at most 5 times, preferably at most 4.5 times, a minimum width of the mounting. This applies in particular to PV module thicknesses of more than 5 mm. .If the thickness of the PV module is less than 4 mm, the overall extent can be greater, but should then, for example, not exceed eight times the minimum width of the mounting. Such designs result in a comparatively narrow lateral extent of the module mount and thus reduced shading.

[0046] According to the invention, the two legs of the module holder are designed as part of a hollow profile. Preferably, the entire module holder can be formed by the hollow profile. The hollow profile can preferably be designed, at least partially, as a longitudinal profile with a constant cross-section.

[0047] According to the invention, the two legs are mechanically connected to each other via a closed (in particular annular) hollow chamber wall of the hollow profile. This closed hollow chamber wall of the hollow profile forms a hollow chamber (designated 32c in the figures). This design according to the invention increases the mechanical strength of the module holder without negatively impacting shading: Preferably, the aforementioned hollow chamber, which is bounded by a closed hollow chamber wall of the hollow profile, is arranged in the plane of the module. In other words, the plane in which the active surface of the PV module, which is held by the hollow profile / module holder, passes through the aforementioned hollow chamber.

[0048] According to the invention, it is therefore provided that a geometric center of gravity of the hollow chamber exhibits a lateral distance transverse to the module plane which is less than 25% of a lateral extent of the hollow chamber transverse to the module plane (in each case with reference to a cross-section through the hollow chamber which runs perpendicular to the module plane - cf. for example the Figure 3 This focus can be particularly favored at the module level, as already mentioned.

[0049] At first glance, an arrangement of the hollow chamber in the module plane as described above appears to be disadvantageous with regard to the effective module area, since it increases the gross size of the module while the net area of ​​the active surface remains the same. However, the invention recognizes that there is a certain trade-off between mechanical stability on the one hand and shading of the active surface on the other. The arrangement according to the invention thus enables, on the one hand, minimal shading and, on the other hand, sufficient stability of the module mounting, particularly when the set is configured as a framed PV module.

[0050] A particularly preferred embodiment may therefore provide that the closed hollow chamber wall forms a hollow chamber which follows the receiving in the insertion direction (i.e. is arranged behind it, preferably in the module plane).

[0051] Additionally, to increase the mechanical stability of the module holder, the hollow profile can be designed with a wall thickening in the area of ​​the mounting, lying in the module plane. This effectively prevents a potentially mechanically weak buckling point from forming in this area, especially if triangular hollow chambers are formed / have been formed in the hollow profile to define the two legs.

[0052] Furthermore, the module holder can have a cross-sectional width at its module-side end, perpendicular to the insertion direction, which corresponds to a maximum of the sum of the minimum width of the receptacle and twice the material thickness of the hollow profile. In this case, only the material thickness of the hollow profile adjoins the receptacle at the module-side tip of the module holder on both the front and rear sides. This design ensures excellent mechanical strength, particularly along the respective longitudinal or transverse side of the module that is to be stabilized by the module holder, while simultaneously minimizing material usage and thus costs. At the same time, the tapered cross-section at the module-side end of the module holder also minimizes the shading effect.

[0053] To increase the strength of the module holder, a particularly preferred embodiment provides that the front and rear legs, which define the receptacle, are each formed by means of a self-contained hollow chamber wall (which may preferably have a triangular cross-section) of the hollow profile. Thus, each of the two legs can form a respective hollow chamber, which, with respect to the insertion direction, is arranged to the left and right of the receptacle. With respect to the active area, these two hollow chambers are therefore located in front of and behind the receptacle, respectively, and behind the PV module inserted into the receptacle.

[0054] A module holder according to the invention can, for example, be designed as a (particularly single) module holding element. Thus, the module holder can only encompass a partial section of the circumferential outer edge of the associated PV module or at least support it on one side. It is preferred if the set comprises several such module holding elements or module holders, each of which encompasses or at least supports partial sections of the outer edge, i.e., in particular partial sections of a respective longitudinal or transverse side of the PV module.

[0055] In an alternative embodiment, the set comprises at least four module mounts that together form a module frame, preferably rectangular, surrounding the PV module. The module frame can thus be self-contained. For this purpose, the module mounts can be joined to form the module frame at several points. Joining multiple module mounts to form the module frame can be achieved using standard corner connectors. These corner connectors can be inserted into the respective profiles of two module mounts to connect them.

[0056] It is also possible to design the module frame in which the distance between the tips of the legs of the respective module support (which stabilizes the PV module on its transverse or longitudinal side) and the outer edge of the active area is chosen to be different, relative to the front and / or rear. However, especially with an almost symmetrical cross-section of the module frame, the respective distances can also be the same. A preferred embodiment, however, provides that the distance between the tip of an upper module support, located on the top side of the PV module, is chosen to be greater than the distance between the tip of a lower module support, located on the bottom side of the PV module, in each case relative to the active area of ​​the PV module.Such designs can optimize space utilization, which means that, with respect to a certain length or height of the supporting structure of a PV system in which the set is installed multiple times, a larger total active area can be arranged.

[0057] Such a module frame can, for example, have a cross-sectional shape on both the front and back sides, relative to a central plane of the module frame running parallel to the active area of ​​the PV module, resembling a beveled passe-partout, similar to a picture frame. The beveled surfaces thus enable the desired large angles of incidence.

[0058] It is important to note at this point that not all four module mounts need to have a convex profile according to the invention. For example, a greater distance to the active surface on a lower module mount can be dispensed with because, in the final mounting position, the sun's rays always strike the vertically oriented active surface of the PV module from above, but never from below (therefore, the aforementioned lower module mount can extend right up to the active surface). For the same reason, even a chamfer on and / or a convex shape of the lower module mount can be omitted.However, for reasons of more efficient manufacturing, designs are preferred in which at least the two vertically running left and right module brackets of the module frame have the same cross-sectional profile and the upper and lower module brackets of the module frame also have the same cross-sectional profile.

[0059] A particularly preferred design is one in which all four module holders of the module frame have an identical cross-sectional profile. This simplifies assembly at the joints.

[0060] It is also possible for the module frame to have a first cross-section along one longitudinal side of the photovoltaic module and a second cross-section along one transverse side. The second cross-section, which stabilizes the transverse side of the PV module, can offer higher mechanical stiffness and / or be larger, particularly wider, than the first cross-section, which stabilizes the longitudinal side of the PV module. This allows for minimal material usage while still providing sufficient stabilization of the PV module.

[0061] Various designs are possible for holding the edge of the PV module in the mount. For example, the edge can be held in place by clamping and / or adhesive, which can be achieved particularly well with adhesive tape. According to a preferred embodiment, the edge of the PV module is sealed in the mount using a sealant. Liquid silicone adhesives are particularly suitable as sealants or sealing adhesives. These can cure in the mount and thus fill any remaining gaps between the PV module and the module holder. When using adhesive tapes, it is advantageous to design the mount in a V-shape, so that the width of the mount decreases in the insertion direction.

[0062] In general, it is advantageous for shading if a tip of the front leg and / or the rear leg forms or defines the module-side end of the module holder. This feature distinguishes the inventive embodiments from previously known module frames in which a stabilizing leg is arranged laterally for receiving and protrudes beyond the receiving area on the module side.

[0063] To solve the aforementioned problem, the invention further provides the features of claim 12, which relates to a PV system. In particular, the invention proposes that, to solve the problem in a PV system of the type described above, the frameless PV modules are each attached to the supporting structure by means of at least one module holder, preferably at least two module holders. Furthermore, it is provided that each bifacial PV module and the associated at least one module holder each form a set, as described above or according to one of the claims relating to a set according to the invention.

[0064] Two posts and two beams of the supporting structure can define a substantially rectangular mounting area in which at least one of the PV modules is arranged. The posts and beams can preferably be designed as longitudinal metal profiles. These profiles can be manufactured very simply by cold forming, i.e., as so-called cold-formed sections. The module mounting, on the other hand, can be manufactured, in particular, by means of aluminum extrusion.

[0065] The posts of the supporting structure can, for example, be arranged in a row to create a solar fence. To implement a large-scale photovoltaic system, the posts can also be arranged in spaced rows. In this case, the posts in a row can essentially form a single plane.

[0066] A space can be left open between the soil and the lowest beam of the supporting structure to allow for agricultural use of this space between the posts. Similarly, a space formed between the aforementioned rows of posts can be used for agricultural purposes.

[0067] Conventional PV modules typically have a rectangular shape, for example with an aspect ratio of approximately 2:1. In a PV system according to the invention, such PV modules can be mounted on the supporting structure in both landscape and portrait formats.

[0068] According to one possible embodiment, the module holders can be inserted into a respective receptacle formed by one of the bars or posts, preferably in a rotationally fixed manner.

[0069] It is therefore specifically proposed to use a set consisting of a module holder and an associated bifacial PV module, as described above or claimed herein, for attachment to a support structure in order to form a high-performance and extremely (wind-)stable PV system. The PV system can be assembled by first mounting the support structure, i.e., the posts and the associated crossbeams, thereby creating essentially rectangular mounting areas between the posts. Subsequently, one or more sets according to the invention can be attached to the mounting area, i.e., to the support structure, to complete the PV system.

[0070] The respective set, which consists of a PV module and the associated at least one module holder, can, for example, include a module holder that is attached to one of the posts, preferably by means of separate fastening elements. It can also be provided, additionally or alternatively, that the respective set includes a module holder that is attached below one of the beams, preferably by means of separate fastening elements. These module holders attached to the posts and / or beams are then thus designed with features according to the invention (as described above).

[0071] The mechanical connection of the respective PV module to the beams and / or posts of the supporting structure can therefore be realized exclusively via (separate) module mounts. However, according to the invention, not all of these module mounts need to be designed with a convex profile; this applies particularly to module mounts that grip a horizontally extending underside of the PV module, since no shading of the active area occurs there when sunlight strikes from above. Therefore, these lower module mounts do not necessarily need to have chamfers, for example.

[0072] A PV system according to the invention can thus comprise a support structure with beams, on the underside of which a module holder of one of the aforementioned sets is suspended, preferably by means of separate fastening elements. Furthermore, the support structure can have beams on the upper side of which a module holder of one of the aforementioned sets is attached, preferably by means of separate fastening elements. In both cases, a cross-section of the respective beam, which runs transversely to a longitudinal direction of the beam, can be selected such that a respective maximum unshaded angle of incidence, at which a respective incident sunbeam can reach the active surface of the PV module from the front or the back, is determined by an outer contour of the module holder (and not by an outer contour of the beam used).In other words, with this design, the angle of incidence is restricted by the bar only to the same extent as by the module mounting. To achieve this, the bar can have a chamfer on its underside, both front and back, relative to the photovoltaic module.

[0073] In the final mounting position, the cross-section of the bar can thus lie, in particular, within a shading angle spanned in the cross-sectional plane, which originates from an outer edge of the active area of ​​the PV module of the set and which is at most 100°, preferably at most 90°. This effectively prevents the bar from shading the active area of ​​the PV module located beneath it.

[0074] A preferred embodiment of the PV system provides that the beams on whose underside (or top) one of the sets is mounted are designed by means of a longitudinal profile that is semi-open at the top (or bottom). Such a semi-open longitudinal profile can preferably be in the form of a C-profile.

[0075] Furthermore, it may be provided that individual fasteners mentioned above are inserted into, preferably slot-shaped, through-holes on the underside (or top) of the bolts. This allows a module holder of one of the sets, located below (or above) the bolt, to be attached to the bolt.

[0076] Another embodiment provides that the aforementioned fastening elements form respective tabs on the front and back, to which the module holder of the associated set is mounted, preferably clamped or screwed.

[0077] The supporting structure can, for example, also include beams designed with a downwardly semi-open longitudinal profile (these can, of course, be the same profiles, just used in a different orientation). Module brackets can then be mounted above such beams in a similar manner.

[0078] Furthermore, the fastening elements can (relative to the module plane) form front and rear mounting legs that are supported on the inside of the transom in the mounting position. This allows holding forces to be transferred into the transom. For example, such mounting legs can be designed as bent tabs that lie flat against an inner surface of the aforementioned semi-open longitudinal profile. The fastening elements can, in turn, be screwed to the transom, with this screw connection being located in the area of ​​the mounting legs. This allows a contact surface of the respective mounting leg to be pressed against the inside of the transom by means of the screw connection.

[0079] The invention will now be described in more detail with reference to exemplary embodiments, but is not limited to these embodiments. Further embodiments of the invention can be derived from the following description of a preferred embodiment in conjunction with the general description, the claims, and the drawings. The drawings are to be understood schematically and are not necessarily to scale, but only approximately so.

[0080] In the following description of various embodiments of the invention, elements that are identical in function are given identical reference numbers even if they differ in design or shape.

[0081] It shows: Figure 1 shows a previously known module holder in the form of a module frame with a rear stabilizing leg; Figure 2 shows another previously known module holder in the form of a module frame, which is somewhat narrower than that of the Figure 1Figure 3 shows a cross-section of a first module holder designed according to the invention with an inserted associated PV module, Figure 4 shows a cross-section of a second module holder designed according to the invention with an inserted associated PV module, Figure 5 shows the same module holder as in Figure 4 , however, with a different type of PV module, Figure 6 Details of the cross-section of a hollow profile which forms the module holder of the Figures 4 and 5Figure 7 shows a side view (in the y-direction) of a first PV system according to the invention, Figure 8 shows a side view (in the y-direction) of a second PV system according to the invention, Figure 9 shows a side view (in the y-direction) of a third PV system according to the invention, Figure 10 shows a cross-section of a (schematically represented) bar of a PV system, on the underside of which a module holder is mounted, Figure 11 shows a set designed according to the invention consisting of a module holder and an associated PV module, wherein the active surface 9, which defines a module plane, lies in a median plane of the PV module, Figure 12 shows the influence of the offset between the module-side end of a module holder according to the invention and the active surface of a PV module inserted therein, Figure 13 shows a set according to the invention, wherein the active surface of the PV module is offset towards the rear with respect to a plane of symmetry of the associated module holder, Figure 14 shows a set according to the invention.wherein the active surface of the PV module is offset towards the front, with respect to a central plane of the associated asymmetrically designed module holder, Figure 15 a set according to the invention, wherein the active surface of the PV module is arranged in a central plane of the PV module and the module holder is asymmetrically designed, Figure 16 a cross-section of a (schematically represented) bar of a PV system, on the underside of which a set according to the invention is mounted, Figure 17 a top view of a bar of a PV system according to the invention and finally Figure 18 a side view of the bar from , Figure 17 with the PV module mounted underneath, including the associated module frame.

[0082] The Figure 1Figure 1 shows a module holder 6 known from the prior art in the form of a module frame with a rear stabilizing leg 67. The module holder 6 provides a receptacle 13 into which an outer edge 14 of an associated photovoltaic module 2, in the form of a glass laminate, is inserted in an insertion direction 15 and thus held in position. The PV module 2 has an active surface 9 on its rear side, which can receive sunlight from both the front 12 and the rear 11 of the PV module 2 in order to convert the sunlight into electrical current.

[0083] As in Figure 1As can be seen, the mounting 13 is bounded at the front by a front leg 17 and at the rear by a rear leg 16 of the module holder 6. While the sunlight 21 incident on the PV module 2 can reach the outer edge 30 of the active area 9 at the front under a comparatively large maximum unshaded angle of incidence 24, the stabilizing leg 67 protrudes considerably beyond the front and rear legs 17, 16 at the rear. This means that the outermost point 58a of the stabilizing leg 67, which is relevant for the rear shading of the active area 9, protrudes beyond the mounting 13 in the opposite direction to the insertion direction 15. This is disadvantageous because the sunlight 20 incident on the rear 11 of the PV module 2 can only reach the outer edge 30 of the active area 9 at a comparatively small angle of incidence 23.

[0084] The Figure 2shows another example of a previously known module holder 6 with an inserted PV module 2. In comparison to the example of the Figure 1 The active area 9 is now located within the PV module 2. Furthermore, the aforementioned stabilizing leg 67 is, compared to the design according to Figure 1 significantly shorter, which results in less stability of the module holder 6, but already considerably reduces the shading angle 29 (relative to the outer edge 30 of the active area 9) spanned by the module holder 6 (cf. Figure 1 ).

[0085] However, the design of the module holder 6 is also according to Figure 2This is suboptimal for use with a bifacial PV module 2, as the module mount 6 has a considerable lateral distance 60a to the plane 10 of the active surface 9 of the PV module 2, which is often also referred to as the module plane. Therefore, if a sunbeam 20 strikes the PV module 2 from the rear at an angle that – as in Figure 2If the maximum shading-free angle of incidence 23° is exceeded, the module mount 6, more precisely its rear stabilizing leg 67, and in particular the outer point 58a shown, shades the active area 9. Since the lateral distance 60a is comparatively large, even slight exceedances of the maximum shading-free angle of incidence 23° result in a considerable shading length 62° (which depends linearly on 60a). With such solar incidence, the entire edge area of ​​the active area 9, corresponding to the shading length 62°, may no longer receive sunlight and therefore can no longer contribute to power production.

[0086] The Figure 3Figure 1 shows a first example of a set according to the invention, consisting of a module holder 6 and an associated bifacial PV module 2. Here again, the module holder 6 forms a receptacle 13, which is bounded at the front by a front leg 17 and at the rear by a rear leg 16. However, it is immediately apparent that the module-side tips 35 of the two legs 16 and 17 form the module-side end 52 of the module holder 6. The respective outer points 58a, 58b (of the cross-section of the module holder 6, which runs perpendicular to the plane 10 of the active area 9), which are relevant at the front and rear respectively for the shading of the active area 9 by the module holder 6, are thus recognizably set back in the insertion direction 15 and with respect to the two aforementioned tips 35 of the two legs 16, 17. The axial offset of these outer points 58a, 58b to the respective tip 35 is more than the 1.5 times the minimum width of the mounting 13. Crucially, the outer points 58a, 58b relevant for shading must be set back so that the active area 9 remains unshaded. The profile 8 could, for example, also be designed to be open on the top side, meaning that the hollow chamber 32e does not necessarily have to be closed in cross-section; however, this is advantageous for higher mechanical stability of the hollow profile 8 / module holder 6.

[0087] What is striking about the in Figure 3 shown hollow profile 8 (as well as in the case of the Figure 4Furthermore, the specific arrangement of the hollow chamber 32c, which in the example shown is bounded by a wall of the hollow profile 8 that is closed in cross-section, is a key feature. This hollow chamber 32c, preferably its geometric center as shown, lies in the module plane 69, i.e., in the plane in which the active surfaces 9 of the PV modules 2 are located. In addition, the hollow chamber 32c extends both beyond the front 12 of the PV module 2 and beyond its rear 11. As can be seen, Figure 3even the geometric center of gravity 70 of the hollow chamber 32c lies within the module plane 69. Such arrangements and designs of the hollow chamber 32c make it possible to increase the mechanical stability of the hollow profile 8 without compromising its ability to prevent shading, as was often the case with previously known brackets where such a chamber was positioned in front of or behind the module plane. In the example shown, the center of gravity 70 is thus located centrally with respect to the lateral extent of the hollow chamber 32c perpendicular to the module plane 69 (see the double arrow).

[0088] In Figure 3It can also be seen that, to further increase the mechanical stability of the module holder 6, the hollow profile 8 has a wall thickening 71 in the area of ​​the receptacle 13. This wall thickening 71 lies in the module plane 69 and is formed on a wall of the hollow profile 8 that connects the two legs 16 and 17, or rather the two hollow chambers 32a and 32b. This wall also defines the receptacle 13. In this way, a high mechanical strength of the module holder 6 can be maintained even at small shading angles.

[0089] The Figure 4 Figure 1 shows another example of a set according to the invention, consisting of a module holder 6 and an associated PV module. In this example as well, the axial offset of the two outer points 58a and 58b compared to the respective tips 35 of the associated leg 16, 17 is clearly visible. Furthermore, in both examples, the Figures 3 and 4that the respective module holder 6 is designed to be axially symmetric with respect to a central plane 27 of the PV module 2, which thus forms the plane of symmetry 28 of the respective module holder 6. Due to this axial symmetry, the respective lateral distances 60a and 60b between the module plane 10 and the outermost edge of the module holder 6 can be adjusted with comparable mechanical strength, as shown in Figure 3 and Figure 4 As can be seen, each one is designed to be significantly smaller than dimension 60a in the example of the Figure 2 . Accordingly, one can already see in Figure 4 , that the shading length 62 is correspondingly smaller if the maximum front or rear shading-free incidence angle 23, 24 is exceeded.

[0090] In comparison to the previously known example of the Figure 1 In the embodiments according to the invention, the Figures 3 and 4Furthermore, it is striking that large maximum shading-free incidence angles 23, 24 of at least 135° are possible both on the front and rear sides.

[0091] The Figure 5 explains the concept according to the invention again using the same module holder 6, which is already described in Figure 4 was shown and their geometric details in the Figure 6 are illustrated. However, in Figure 5The case shown involves the use of a PV module 2 in which the active surface 9 is laterally offset with respect to a central plane 27 of the PV module 2. Although the PV module 2 is inserted centrally into the receptacle 13 of the module holder 6, and although the module holder 6 remains axially symmetrical with respect to its plane of symmetry 28, the resulting maximum unshaded angle of incidence 23 on the rear side 11 is a few degrees larger than the corresponding maximum unshaded angle of incidence 24 on the front side 12, as can be seen in Figure 5 sees.

[0092] Also in the Figure 5 Thus, a shading angle 29 can be identified that originates from the outer edge 30 of the active area 9 of the PV module 2 and lies in the cross-sectional plane (xy-plane in Figure 5 ) of the module holder 6, which in turn runs perpendicular to the plane 10 (xz-plane in Figure 5 ) of active area 9. How to in Figure 5As can be seen, an outer contour 22 of the module holder 6 lies within this shading angle 29. The module-side end 52 also lies within the shading angle 29. Furthermore, it can be seen that the angle bisector 54 of the shading angle 29 with the plane 10 of the active surface 9 forms a tilt angle 55 of less than 15°. Due to this design of the set consisting of the module holder 6 and the inserted PV module 2, the unshaded angle areas are distributed fairly evenly between the front 12 and the back 11 of the PV module 2. Since the shading angle 29 is also less than 90°, it is ensured that in the case shown, the Figure 5 The maximum shading-free front angle of incidence 24 and the maximum shading-free rear angle of incidence 23 must each be at least 120°.

[0093] In order to achieve such high values ​​for the maximum angles of incidence without shading (23°, 24°), it is crucial that the in Figure 5 The envelope 25 of the module holder 6, illustrated as a dotted line and thus enclosing the outer contour 22, shows a convex shape when viewed in the direction of insertion 15. This is because, as in Figure 5 to see and especially in Figure 6 As illustrated in more detail, the respective front and rear outer contours 22 of the xy cross-section of the module holder 6, which are formed in particular by the two legs 16 and 17, remain within the illustrated chamfer 63, which in each case runs towards the module-side insertion opening 45 of the receptacle 13. In the Figure 6In the example shown, the two chamfers 63 each form an angle of more than 145° to the active surface 9. Naturally, it would not be critical for the shading if the outer contour 22 deviated inwards from the chamfer 63 at some points (i.e., towards the plane 10 of the active surface 9).

[0094] In Figure 5 It can also be seen that the edge 14 of the PV module 2 is sealed in the recess 13 by means of a sealant 41.

[0095] Based on the Figure 6 It is also clearly visible that the two legs 16, 17 of the module holder 6 each have a lateral extension 31, transverse to a central plane 27 of the (in Figure 6The dimensions of the PV module 2 (not shown) and each measured from image 13, show that they constitute more than 75% of the minimum width 41 shown in image 13. It is initially irrelevant whether the center plane 27 of the PV module 2 corresponds to a center plane of image 13 or to the one shown in Figure 6 The symmetry plane 28 of the module holder 6 is laterally offset. An advantage of such a large respective front and rear lateral extension 31 is that the module holder 6 can offer considerable rigidity, while at the same time ensuring sufficient freedom from shading.

[0096] In the Figures 3 to 6 It can also be seen that the module holder 6 is each formed by a hollow profile 8, which in turn is designed as a longitudinal profile with a constant cross-section. Both in the design according to Figure 3 as well as in the case according to the Figures 4 to 6This includes a self-contained hollow chamber wall 33, which is located in the Figures 3 and 6 Each is illustrated with a dashed line. This closed hollow chamber wall 33 mechanically connects the two legs 16, 17 to each other, thus ensuring excellent stability of the module holder 6.

[0097] Especially in Figure 6 It is also clearly visible that both the front and rear legs 17, 16 are each formed by means of a self-contained hollow chamber wall 33 of the hollow profile 8. These hollow chamber walls 33 have a triangular cross-section. It is also evident that in Figure 6The module holder 6 has a cross-sectional width 59 at its module-side end 52, perpendicular to the insertion direction 15, which corresponds exactly to the sum of the minimum width 41 of the receptacle 13 and twice the material thickness 56 of the hollow profile 8. Such a design is particularly advantageous because it allows the module-side end 52 to be installed with a very small offset 57 (cf. Figure 12 ) can be positioned close to the outer edge 30 of the active area 9 of the PV module 2. This allows for a compact design that minimizes the space required for the set per active area 9 of the PV module 2.

[0098] The Figure 7Figure 1 shows a first example of how a photovoltaic system 1 can be realized using a set according to the invention, in which several bifacially designed PV modules 2 are mounted upright on a support structure 3. The support structure 3 comprises several vertical posts 4 extending in the z-direction, which are anchored in the ground. Horizontally extending crossbars 5 are attached to the posts 4, thus connecting each pair of adjacent posts 4. As can be seen in Figure 7 As can be clearly seen, this essentially defines rectangular mounting fields in which at least one PV module 2 can be arranged; in the example of the Figure 7For example, only a single PV module 2 is suspended in the mounting field in a "landscape" orientation, so that the long side 38 of the PV module 2 runs horizontally along the bars 5. In other configurations, however, several PV modules can also be mounted one above the other and / or next to each other within the mounting field.

[0099] As in Figure 7As can be seen, the module mounting 6 of the set is designed in the form of several module holding elements 43, each of which only engages a section 44 of the circumferential outer edge 14 of the PV module 2. The module holding elements 43 either establish a mechanical connection between one of the bars 5 and the PV module 2 or between the PV module 2 and one of the posts 4. The upper and lower module holding elements 43, which hold the PV module 2 on its horizontal longitudinal sides 38, must possess considerable mechanical strength to reliably transfer the wind loads acting on the surface of the PV module 2 into the respective bars 5.In addition, a direct mechanical connection between two PV modules 2 arranged one above the other or next to the other can also be realized via such a module holding element 43; in this case, the corresponding module holding element 43 thus provides a receptacle 13 on both sides into which the edge 14 of the respective PV module 2 is inserted.

[0100] The Figure 8 Figure 1 shows another PV system 1 according to the invention, wherein the set comprises at least four module holders 6a, 6b, 6c, 6d, which together form a rectangular module frame 34 that surrounds the PV module 2. The four module holders 6 are joined together at several joints 42 by means of corner connectors to form the module frame 34.

[0101] Unlike the example of the Figure 7 , is in Figure 8It can be seen that the spacing 36a of the tip 35 of the upper module support 6a, which is located on the top of the PV module 2, is larger than the spacing 36c of the tip 35 of the lower module support 6c, which is located on the underside of the PV module 2, in each case with respect to the active area 9. Since the sun's rays always strike from above, the lower module support 6c can be positioned very close to the outer edge 30 of the active area 9 without causing significant shading. This design allows the overall height of the PV system 1 to be reduced, which is advantageous for withstanding wind loads, especially when several PV modules 2 are stacked on top of each other.

[0102] The Figure 9Figure 1 shows another possible embodiment of the set according to the invention: Here, a total of four module holders 6 in the form of separate module holding elements 43 are also provided, which, however, unlike in the example of the Figure 8 , are not joined together to form a surrounding module frame 43.

[0103] The Figure 10 shows how, for example, the upper module bracket 6 in Figure 9 (or the module holder 6a of the Figure 8 ), which encompasses the upper longitudinal side 38 of the PV module 2, can be connected to the bar 5 above it. Separate fastening elements 37 are provided for this purpose, which are inserted into slot-shaped through-holes 49 on the underside of the in Figure 10 shown bar 5 are inserted (see also Figure 17 ), in order to attach the module holder 6, located below the bar 5, to the bar 5. Here, the in Figure 10The fastening element 37 shown has a tab 50 on both the front 12 and the back 11 (see also Figure 18 ), to which the module bracket 6 is attached.

[0104] In Figure 10 Is module holder 6 analogous to the example of the Figure 6 designed with a respective front and rear chamfer 63, whereby in principle, as is shown in Figure 4 As illustrated, a shading angle of less than 90° can be achieved, so that at least a maximum unshaded angle of incidence of 110° should be attainable on both the front and back sides. For this, however, a suitable PV module 2 must be selected, whereby the lateral position of the active surface 9 is particularly important, as is the offset 57 that exists between the module-side end 52 of the module holder 6 and the outer edge 30 of the active surface 9 (compare this to...). Figure 12). This offset 57 depends on the one hand on the so-called cell edge distance 61, i.e. the distance between the outer edge of the PV module 2 and the outer edge 30 of the active area 9 (see also Figure 2 or Figure 12 ) as well as the insertion depth of the PV module 2 into the receptacle 13 of the module holder 6 (the distance 66 between the outer edge 14 of the PV module 2 and a stop formed by the module holder 6 in the receptacle 13 can vary - see also Figure 3 ). In the Figure 10 In the example shown, however, both the lateral offset of the active surface 9 to the mid-plane 27 of the PV module 2 and the offset 57 between the outer edge 30 of the active surface 9 and the module-side end 52 of the module holder 6 are so unfavorably chosen that a shading angle of approximately 110° results, and in addition, a strong tilt of the shading angle 29 towards the front 12 (note the angle bisector 54 in the figure). Figure 10, which assumes a tilt angle 55 of more than 20° with respect to the plane 10 of the active surface 9.) Therefore, only a maximum shadow-free angle of incidence onto the active surface 9 of 105° can be achieved on the front side, which would lead to power losses.

[0105] As the Figure 16 However, by using a PV module 2 with a centrally arranged active area 9, with otherwise identical construction of the module holder 6 and the associated bar 5, the situation can be improved so much that the shading angle is now only 65° and maximum shading-free incidence angles of more than 145° can be achieved on both the front and back sides.

[0106] This situation is also described in detail in Figure 11As shown: It can be seen that the front and rear chamfers 63 of the module holder 6, which are each symmetrically formed with respect to the shown plane of symmetry 28 of the module holder 6, span an opening angle 56 of approximately 65°. As shown in Figure 11 If a PV module 2 is used in which the active surface 9 is arranged in a central plane 27 of the PV module 2, the PV module 2 can be inserted into the receptacle 13 just far enough that the shading angle 29 acting on the outer edge 30 of the active surface 9 corresponds exactly to the opening angle 56, as shown in Figure 11 is illustrated.

[0107] The Figure 12In contrast, the left half shows that the shading angle 29 increases considerably when the active area 9 is moved closer to the module-side end 52 of the module holder 6. This closer placement initially appears advantageous in order to maximize the size of the active area 9 relative to the overall size of the PV module 2, thus enabling a comparatively small cell edge spacing 61. However, the disadvantage of a small offset 57 is that the maximum shading-free angles may then be limited (taking into account tolerances when inserting the PV modules 2 into the module holder 6).

[0108] The right part of the Figure 12This shows that the shading angle 29 caused by the module holder 6 can even be smaller than the opening angle 56 created by the module holder 6, namely when the aforementioned offset 57 is chosen to be correspondingly large. However, such a large offset leads to a loss of active area 9 and thus to lower power production. Therefore, the aforementioned offset 57 should preferably be no more than 20% larger than a minimum offset that must be maintained to ensure the desired maximum unshaded angle of incidence on the front 12 or the back 11. For example, in Figure 11 The active area 9 can be moved slightly closer to the module-side end 52, provided that only a maximum shadow-free front and rear incidence angle of 135° is desired.

[0109] The Figure 13 starts from the example of Figure 11However, here a PV module 2 is inserted into the same module holder 6, in which the active surface 9 is laterally offset from the center plane 27 of the PV module 2. Nevertheless, a comparatively large maximum unshaded angle of incidence 23, 24 on both the front 12 and the back 11 was ensured by choosing a comparatively large offset 57. This also results in a small tilt angle 55 of less than 15° and a comparatively small shading angle of approximately 55°. Such a design can be advantageous, for example, when a PV module 2 is used, which already has a comparatively large cell edge spacing 61 (cf. Figure 12 ) exhibits.

[0110] The Figure 14Figure 1 shows another example of a set designed according to the invention. Here, however, a module holder 6 is used which is designed asymmetrically with respect to the central plane 27 of the PV module 2 shown. As can be seen, the lateral distances 60a and 60b between the module plane 10 of the active area 9 and the respective outer points 58a, 58b of the module holder 6 differ only very slightly. Thus, the fact that the active area 9 of the PV module 2 is offset towards the front 12 is at least partially compensated for by the asymmetrical design of the module holder 6, so that a comparatively small shading angle of approximately 65° can still be achieved, with a comparatively small offset 57 between the module-side end 52 of the module holder 6 and the outer edge 30 of the active area 9.

[0111] As the example of Figure 15As shown, an asymmetrically designed module holder 6 can also be used according to the invention with a PV module 2 whose active surface 9 is positioned centrally with respect to the outer edges / surfaces of the PV module 2. The asymmetry of the module holder 6 can be seen, for example, in the different lateral extensions 31 of the two legs 16 and 17.

[0112] All embodiments according to the invention are described below. Figures 3 to 9In all embodiments 11 to 16, the common feature is that the module mounting 6 used has recessed outer points 58a and 58b, such that the module-side tips 35 of the two legs 16 and 17 form the module-side end 52, that a maximum unshaded angle of incidence of at least 110° is ensured on both the front and rear sides, and that the tilt of the respective set shading angle 29, relative to the plane 10 of the active surface 9, is at most 15°. This allows for high efficiency in solar power production in all these embodiments, both with front and rear irradiation of the bifacial PV module 2.

[0113] The Figures 17 and 18 The figures show perspective views of a horizontally extending upper beam 5 of a supporting structure 3 of a PV system 1 according to the invention, the design of which corresponds to the scheme of Figure 16corresponds. This can be seen in the Figures 17 and 18 A separate fastening element 37, as previously explained, is inserted into the upwardly semi-open bar 5, which is designed by means of a C-profile, in order to fasten the module holder 6 arranged below the bar 5, together with the PV module 2 held by it, to the bar 5. Figure 18 The two front tabs 50, formed by the fastening element 37 for holding the module holder 6, can be seen. Figure 17 It can also be seen that the fastening element 37 forms a support leg 68 on both the front and rear sides, which in the mounting position is supported on the inside of the bolt 5 and screwed to it.

[0114] In summary, to securely hold an upright photovoltaic (PV) module 2, a sufficiently strong module support 6 is proposed, which can stabilize one or more outer edges of the PV module 2 against wind loads and simultaneously minimize the susceptibility of the PV module 2 to shading by the associated module support 6. For this purpose, the module support 6 is designed with a convex shape, allowing large maximum unshaded angles of incidence 23, 24 on the front and rear sides, while simultaneously achieving the smallest possible lateral extent of the module support 6 in a direction perpendicular to an active surface 9 of the PV module 2, both on the front and rear sides.This makes it possible to obtain high-performance PV systems 1 based on a supporting structure 3 which, with the help of module holders 6 designed according to the invention, supports large-area bifacial PV modules 2 upright and largely free from shading. Reference symbol list

[0115] 1 Photovoltaic system 2 Photovoltaic module 3 Support structure 4 Post 5 Beam 6 Module holder (for positioning / holding 2) 7 Module plane (formed by several 2 or by 9) 8 Hollow profile 9 Active surface (of 2) 10 Plane of the active surface (i.e., plane of 9) 11 Back (of 2) 12 Front (of 2) 13 Receptacle 14 (Outer) edge (of 2) 15 Insertion direction (along which 2 can be inserted into 13) 16 Rear leg (of 6, defining 13) 17 Front leg (of 6, defining 13) 18 Slide-on direction (in which 6 can be slid onto 2, opposite to 15) 19 Cover / protective layer, in particular designed as an anti-reflective layer 20 Incident sunbeam (falls on 11) 21Incident sunbeam (falls on 12) 22Outer contour (of 6) 23Maximum shading-free angle of incidence (with respect to 11) 24Maximum shading-free angle of incidence (with respect to 12) 25Enveloping (of 6,seen in the direction of 15) 26 Surface normal (on 9 or 10) 27 Middle plane (of 2 or 6) 28 Plane of symmetry (of 6) 29 Shading angle 30 (Outer) edge (of 9) 31 Lateral extension (of 16, 17, perpendicular to 10 and measured from 13) 32 Hollow chamber 33 Hollow chamber wall (connecting 16 and 17) 34 Module frame 35 Module-side tip (of 16 / 17) 36 Spacing (between 35 and 9) 37 Fastening element (for attaching 6 / 34 to 4 / 5) 38 Longitudinal side (of 2 / 14) 39 Transverse side (of 2 / 14) 40 Insertion depth (of 2 in 6 / 13) 41 Minimum width (of 13) 42Joining point (between 6 / 43, for forming 34) 43Module holding element 44Subsection (of 14) 45Insertion opening (of 13, for inserting 2 into 13) 46(lateral) Total extension (of 6) 47Screw connection 48Longitudinal direction (of 5) 49Through opening (formed in 5, for inserting 37 into 5) 50Tabs (of 37,for attaching 6) 51 chamfer (at 5) 52 module-side end (of 6) 53 longitudinal profile 54 angle bisector (of 29) 55 tilt angle 56 opening angle (of 6) 57 offset (between 30 and 52) 58 outer points (of 6, each laterally spaced from 10) 59 cross-sectional width (of 52) 60 lateral distance between the module plane and the module holder, in particular lateral cell plane-frame distance (= lateral distance between 58 and 10) 61 cell edge distance (distance between outer edge of 2 and 30) 62 shading length 63 chamfer 64 maximum insertion depth (of 13) 65 maximum width (of 6 in the direction of 15) 66 distance (between 14 and stop formed by 6) 67 Stabilizing leg 68 Mounting leg (from 37 to the mounting at 5) 69 Module plane 70 Geometric center of gravity (from 32c) 71 Wall thickness thickening,

Claims

1. A set formed of a module holder (6) and an associated bifacial photovoltaic module (2), - wherein the photovoltaic module (2) is designed as a frameless laminate and has an active surface (9) that can receive sunlight from a front side (12) and a rear side (11) of the photovoltaic module (2) in order to convert the sunlight into electrical current, wherein the active surface (9) of the photovoltaic module (2) extends in a module plane (10, 69), - wherein the module holder (6) provides a receptacle (13) into which an outer edge (14) of the laminate is inserted in an insertion direction (15) and thus held in position, - wherein the receptacle (13), relative to a plane (10) of the active surface (9) of the frameless photovoltaic module (2), is delimited at the front by a front leg (17) and / or at the rear by a rear leg (16) of the module holder (6), wherein: - respective front and rear outer points (58a, 58b), which are relevant for shading the active surface (9) by the module holder (6), of a cross-section of the module holder (6) extending perpendicularly to a plane (10) of the active surface (9) are set back in the insertion direction (15) and with respect to respective module-side tips (35) of the two legs (16, 17), - the two legs (16, 17) of the module holder (6) are designed as part of a hollow profile (8), - a closed hollow chamber wall (33) of this hollow profile (8) forms a hollow chamber (32c), and - a geometric center of gravity (70) of this hollow chamber (32c) has a lateral distance transverse to the module plane (10, 69), wherein said lateral distance is less than 25% of a lateral extent of the hollow chamber (32c) transverse to the module plane (10, 69).

2. The set according to claim 1, - wherein an outer contour (22) of the module holder (6), in particular the envelope (25), lies within a shading angle (29), which extends in the cross-sectional plane and starts from an outer edge (30) of the active surface (9), with respect to a cross-sectional plane of the module holder (6) extending perpendicularly to a plane (10) of the active surface (9), and - in that an angle bisector (54) of the shading angle (29) with the plane (10) of the active surface (9) encloses a tilt angle (55) of at most 15°, preferably at most 10°.

3. The set as claimed in claim 2, - wherein the shading angle (29) is at most 100°, preferably at most 90°.

4. The set according to one of the preceding claims, - wherein an / the outer contour (22) of the module holder (6) is designed in such a way that both - a maximum shading-free angle of incidence (23) at which an incident sun ray (20) can reach an outer edge (30) of the active surface (9) from the front side (12), as well as - a maximum shading-free angle of incidence (24) at which an incident sun ray (21) can reach the outer edge (30) of the active surface (9) from the rear side (11), in each case, measured in relation to the active surface (9), is at least 110°, preferably at least 120°, particularly preferably at least 135°.

5. The set as claimed in one of the preceding claims, wherein the two legs (16, 17) of the module holder (6) form a respective outer contour (22) which remains within a bevel (63) of the module holder (6) which runs towards a module-side insertion opening (45) of the receptacle (13), - preferably wherein the respective bevel (63) forms in each case an angle to the active surface (9) of at least 110°, preferably of at least 120°, particularly preferably of at least 135°, - in particular wherein the respective outer contour (22) of one of the legs (16, 17) deviates in places from the bevel (63) inwards towards the receptacle (13).

6. The set as claimed in one of the preceding claims, wherein the two legs (16, 17) of the module holder (6) each show a lateral extent (31), transverse to a center plane (27) of the photovoltaic module (2) and in each case measured from the receptacle (13), which is at least 25%, preferably at least 50%, particularly preferably at least 75%, of a minimum width (41) of the receptacle (13) in the direction of a surface normal (26) of the active surface (9), - in particular wherein a width of the receptacle (13) increases in the insertion direction (15), and / or - wherein the center plane (27) of the photovoltaic module (2) is laterally offset from a center plane of the receptacle (13) or from a center plane (27) of the module holder (6).

7. The set as claimed in one of the preceding claims, wherein the entire module holder (6) is formed by the hollow profile (8), - particularly preferably wherein the two legs (16, 17) are mechanically connected to one another via a closed hollow chamber wall (33) of the hollow profile (8), and / or - wherein the hollow chamber (32c) follows the receptacle (13) in the insertion direction (15), and / or - wherein the hollow profile (8) has a wall thickness thickening (71) in the region of the receptacle (13), which thickening lies in the module plane (69), and / or - wherein the module holder (6) has at its module-side end (52) a cross-sectional width (59) transverse to the insertion direction (15), which corresponds at most to the sum of the minimum width (41) of the receptacle (13) and twice a material thickness (56) of the hollow profile (8).

8. The set as claimed in one of the preceding claims, wherein the module holder (6) is designed as a module holding element (43) which embraces only a partial portion (43) of the circumferential outer edge (14) of the photovoltaic module (2) or supports it at least on one side, - preferably wherein the set (1) comprises a plurality of such module holding elements (34), each of which embraces or supports at least on one side partial portions (43) of the outer edge (14), in particular partial portions (43a, 43b) of a respective longitudinal side (38) or transverse side (39) of the photovoltaic module (2).

9. The set as claimed in one of claims 1 to 7, wherein the set comprises at least four module holders (6a, 6b, 6c, 6d) which together form a preferably rectangular module frame (34) surrounding the photovoltaic module (2), - in particular wherein the module holders (6a, 6b, 6c, 6d) are joined together at several joints (42) to form the module frame (34), - preferably wherein a spacing (36a) of a tip (35) of an upper module holder (6a), which is arranged on an upper side of the photovoltaic module (2), is selected to be greater than a spacing (36c) of a tip (35) of a lower module holder (6c), which is arranged on an underside of the photovoltaic module (2), in each case in relation to the active surface (9).

10. The set as claimed in one of the preceding claims, wherein the edge (14) of the photovoltaic module (2) in the receptacle (13) - is held in a clamped manner and / or - is glued in, in particular with the aid of an adhesive tape, - preferably is glued sealingly by means of a sealing compound (41).

11. The set as claimed in one of the preceding claims, wherein a tip (35) of the front leg (17) and / or of the rear leg (16) forms the module-side end (52) of the module holder (6), - preferably wherein the module-side end (52) lies within the shading angle (29).

12. A photovoltaic system (1) having - a support structure (3) on which a plurality of bifacial photovoltaic modules (2) are arranged upright, - wherein the support structure (3) has a plurality of posts (4) which are fastened to or in the ground, in particular anchored, and wherein transoms (5) are fastened to the posts (4) and in each case connect two adjacent posts (4) to one another, characterized in - that the photovoltaic modules (2) are each designed as frameless laminates and are fastened to the support structure (3) by means of at least one respective module holder (6), - that the respective bifacial and frameless photovoltaic module (2) and the associated at least one module holder (6) each form a set (1) which is designed as claimed in one of the claims 1 to 11.

13. A photovoltaic system (1) as claimed in the preceding claim, wherein the respective set (1) formed by a photovoltaic module (2) and the associated at least one module holder (6) - comprises a module holder (6) which is fastened to one of the posts (4), preferably by means of separate fastening elements (37), and / or - comprises a module holder (6), which is fastened below one of the transoms (5), preferably by means of separate fastening elements (37), and / or - comprises a module holder (6), which is fastened above one of the transoms (5), preferably by means of separate fastening elements (37).

14. The photovoltaic system (1) as claimed in one of claims 12 to 13, wherein the support structure (3) comprises transoms (5), on the underside of which a module holder (6) of one of the sets (1) is suspended, preferably by means of separate fastening elements (37), and / or comprises transoms (5), on the upper side of which a module holder (6) of one of the sets (1) is fastened, preferably by means of separate fastening elements (37), and - wherein a cross-section of the respective transom (5), which extends transversely to a longitudinal direction (48) of the transom (5), is selected such that a respective maximum shading-free angle of incidence (23, 24), at which a respective incident sun ray (20, 21) can reach the active surface (9) of the photovoltaic module (2) from the front side (12) or from the rear side (11), is defined by an outer contour (22) of the module holder (6).

15. The photovoltaic system (1) as claimed in one of claims 12 to 14, wherein those transoms (5) on the underside of which one of the sets (1) is mounted are formed by means of a longitudinal profile (53) which is half-open at the top, preferably in the form of a C-profile, and / or - wherein individual ones of the fastening elements (37) are inserted into, preferably slot-shaped, push-through openings (49) on the underside of transoms (5) in order to fasten a module holder (6), arranged under the transom (5), of one of the sets (1) to the transom (5), and / or - wherein the fastening elements (37) form respective lugs (50) on the front and rear sides, to which the module holder (6) of the associated set (1) is mounted, preferably clamped or screwed.