Photovoltaic unit for providing electrical power, photovoltaic system and method for producing a photovoltaic unit

Abstract

The invention relates to a photovoltaic unit (100) for providing electrical power, comprising at least two photovoltaic elements (106, 108) connected to an electrical connector (110), the electrical connector (110) having a main extension direction (112), a transparent encapsulation material (114), within which the at least two photovoltaic elements (106, 108) are embedded, a front cover unit (116), which covers the encapsulation material (114) and forms a front face (103) of the photovoltaic unit (100), the front cover unit (116) comprising a plastics material (118) or the front cover unit (116) consisting of a plastics material (118), the plastics material comprising unidirectionally fibre-reinforced plastics layers (119, 119', 119'') arranged on top of one another, fibres (120, 120', 120'') of at least one of the unidirectionally fibre-reinforced plastics layers (119, 119', 119'') being oriented in parallel with the main extension direction (112) of the electrical connector (110), and the fibres (120, 120', 120'') being formed as continuous fibres.

Description

[0001] Photovoltaic unit for providing electrical energy, photovoltaic system and method for manufacturing a photovoltaic unit

[0002] The invention relates to a photovoltaic unit for providing electrical energy, a photovoltaic system and a method for manufacturing a photovoltaic unit.

[0003] Photovoltaic units are generally well-known. Photovoltaic units are also referred to as photovoltaic modules or PV modules. PV modules comprise photoactive photovoltaic elements, also known as solar cells, which are typically arranged in a single plane within the PV module and interconnected by electrically conductive structures, such as conductor tracks. The solar cells are usually encased in additional materials to protect them from external influences, particularly moisture and hail. One requirement for PV modules is that they achieve a high power output. For this to be successful, the material on the side of the PV module facing a light source, especially the sun, must have a high transmittance for light energy.To prevent losses of incident light due to reflection at internal material interfaces, the materials used in the PV module are arranged in such a way that there is essentially no air gap at the interfaces between adjacent materials. Furthermore, the PV modules are designed to withstand the changing mechanical stresses encountered during operation, particularly wind and snow loads, as well as thermal stresses resulting from diurnal temperature variations.

[0004] A common design for PV modules involves embedding the solar cells in a transparent, elastomer-like capsule material that completely encloses the solar cells or is at least connected to one side of them. The outer boundary of the PV module consists of a glass plate on the front, which faces the light source during normal operation, and a backsheet or glass plate on the back, which is usually bonded to the capsule material.

[0005] If a backsheet is applied to the rear side, this PV module is also called a glass-foil module. If a glass plate is applied to the rear side, this PV module is also called a glass-glass module. Glass-glass modules generally have sufficient strength if the glass plates are of adequate thickness. Glass-foil modules are usually fitted with a frame, for example, made of aluminum profiles, to ensure adequate module strength. However, such PV modules generally have a shorter lifespan. In addition to these designs, there are other module design variants with alternative module structures and manufacturing technologies.

[0006] The most common manufacturing process for PV modules is lamination. This involves stacking the individual components on top of each other, creating a vacuum inside the laminator, and increasing the temperature so that the encapsulation material melts and encases the solar cells without bubbles. In glass-foil modules, the component stack comprises a front glass plate, a layer of encapsulation material, solar cells, another layer of encapsulation material, and a backsheet. In glass-glass modules, a glass plate is used instead of a backsheet.

[0007] Instead of a glass front panel, the use of a plastic panel is increasingly being pursued to reduce the weight of PV modules. This typically involves a frame on the back and a thick, transparent plastic panel on the front. Reduced weight is particularly advantageous for installing PV modules on roofs, for example, as a retrofit solution. A disadvantage of PV modules with a plastic front panel is that after a short period of operation, individual or multiple solar cells may fail, necessitating module replacement.

[0008] US patent 2013 / 192665 A1 discloses a photovoltaic module with solar cells surrounded by an elastic material, which is itself enclosed in a glass fiber reinforced plastic. The glass fiber reinforced plastic is intended to improve fire resistance.

[0009] US patent 10,553,737 B2 discloses a PV module with solar cells arranged in embedding layers, wherein the embedding layers may be made of fiber-reinforced plastic.

[0010] EP 2 863 443 B1 discloses a photovoltaic panel with a solar cell that is covered on both sides by a transparent composite material made of a glass fiber reinforced plastic, wherein fibers are arranged as a fabric.

[0011] The aforementioned publications share the common feature that, while solar modules with a plastic front face meet the required standards, they have a shorter lifespan. In particular, solar cells and conductive traces fail more quickly with this design, necessitating replacement. An object of the invention is to provide a photovoltaic unit for generating electrical energy, a photovoltaic system, and a method for manufacturing a photovoltaic unit that reduce or eliminate one or more of these disadvantages. In particular, an object of the invention is to provide a solution that improves the lifespan of photovoltaic modules.

[0012] This problem is solved by a photovoltaic unit, a photovoltaic system, and a method according to the features of the independent claims. Further advantageous embodiments of these aspects are specified in the respective dependent claims. The features disclosed in the claims, the description, and the drawings can be combined individually, in any technologically meaningful way, and further embodiments of the invention are shown.

[0013] According to a first aspect, the aforementioned problem is solved by a photovoltaic unit for providing electrical energy, comprising at least two photovoltaic elements connected by an electrical connector, wherein the electrical connector has a principal direction of extension, a transparent capsule material within which the at least two photovoltaic elements are embedded, a front cover unit covering the capsule material and forming a front face of the photovoltaic unit, wherein the front cover unit comprises a plastic or the front cover unit consists of a plastic, wherein the plastic has at least one unidirectionally fiber-reinforced plastic layer, wherein fibers of the unidirectionally fiber-reinforced plastic layer are aligned parallel to the principal direction of extension of the electrical connector, and wherein the fibers are formed as continuous fibers.

[0014] The invention is based, among other things, on the finding that the materials used in a photovoltaic unit have different coefficients of thermal expansion, which vary in magnitude. This difference can generally be greatest between the plastic components and the photovoltaic elements, which are often made of silicon. Unfilled plastics, for example, can have a coefficient of thermal expansion up to 50 times greater than that of silicon photovoltaic elements. The regular temperature changes during operation, for example between day and night, lead to mechanical stress cycles in the material assembly of the photovoltaic unit and, according to the inventors, are a cause of fatigue failure of the individual components, which necessitates the regular repair or replacement of photovoltaic units with a plastic front surface.This is one of the reasons why front surfaces made of plastic have not become established.

[0015] The invention was further based on the understanding that these thermal cycling stresses lead to the failure of the electrical connector, for example, the conductor tracks between the photovoltaic elements. It is also based on the understanding that this failure phenomenon occurs particularly in modules with a plastic plate on the front, since the plastic plate has a different coefficient of thermal expansion compared to the photovoltaic elements, as mentioned above. The inventors discovered that the failure of the electrical connector can be avoided or delayed by incorporating fiber-reinforced plastic layers into the front cover unit, the fibers of which are at least partially aligned parallel to the electrical connector.This, along with the continuous fibers, stiffens the photovoltaic unit towards the electrical connector in such a way that the temperature-related expansion does not exceed a critical threshold, thus preventing the electrical connector from breaking due to expansion. Furthermore, the invention is based on the finding that the performance of the photovoltaic elements does not suffer any significant loss despite the fiber-reinforced plastic layers of the front cover unit.

[0016] The photovoltaic unit is designed to generate electrical energy. For this purpose, the front of the photovoltaic unit is oriented towards the sun during normal operation, allowing the light energy to be converted into electrical energy by the photovoltaic elements. The photovoltaic unit comprises at least two photovoltaic elements connected by an electrical connector. Photovoltaic elements are also known as solar cells. It is preferred that the photovoltaic unit has a plurality of photovoltaic elements connected to each other by the electrical connector. The photovoltaic elements can, for example, be arranged in the form of so-called strings. It is further preferred that the photovoltaic elements are arranged within a single plane. Furthermore, it may be preferred that the photovoltaic elements are arranged along a curved chord.

[0017] The electrical connector can, for example, be a conductive trace. The electrical connector preferably extends along the at least two photovoltaic elements. The electrical connector can be arranged on, under, and / or next to the at least two photovoltaic elements. The electrical connector can be formed, at least partially, by the fibers of the unidirectional fiber-reinforced plastic layer.

[0018] The main direction of extension corresponds in particular to the orientation of individual strings comprising the serially connected photovoltaic elements. The main direction of extension of the electrical connector is understood to be, in particular, the direction in which the electrical connector extends to its greatest extent. Preferably, the main direction of extension is at least partially a straight line. Alternatively or additionally, the main direction of extension may be or include a curve. Within the main direction of extension, the orientation of the electrical connector may also exhibit individual deviations from the main direction of extension, for example, in the form of a wave, a kink, or a jump, particularly between two adjacent photovoltaic elements.

[0019] It is further preferred that the two or more photovoltaic elements are arranged along a line of arrangement and that their main direction of extension is substantially parallel to this line of arrangement. Along this line of arrangement, the connector may, of course, deviate from parallelism over a single segment, wherein this single segment is, for example, less than 10% of the length of the line of arrangement. The photovoltaic unit further comprises the transparent capsule material within which the at least two photovoltaic elements are embedded. The fact that the at least two photovoltaic elements are embedded within the capsule material means, in particular, that the capsule material defines the position of the photovoltaic elements. The fact that the two photovoltaic elements are embedded within the capsule material means, in particular, that the at least two photovoltaic elements are at least partially surrounded by the capsule material.

[0020] The fact that the capsule material is transparent means, in particular, that it is at least partially transparent. Specifically, this means that the capsule material is not completely opaque. The capsule material can, for example, have a thickness of 0.1 to 3 mm, preferably 0.2 to 2 mm, and most preferably between 0.3 and 1 mm.

[0021] It is preferred that the capsule material is arranged and designed such that it encloses, preferably completely encloses, the at least two photovoltaic elements. If the at least two photovoltaic elements are completely enclosed by the capsule material, the photovoltaic elements are, in particular, embedded in the capsule material.

[0022] The photovoltaic unit also includes the front cover unit, which covers the capsule material. The cover unit can completely or partially cover the capsule material. In normal operation, this means, for example, that the capsule material is arranged vertically beneath the cover unit. The cover unit forms the front of the photovoltaic unit. This means, in particular, that the cover unit faces the sun during normal operation. Sunlight thus first enters the cover unit, passes through it, and then through the capsule material, reaching the photovoltaic cells.

[0023] The front cover unit comprises or consists of the plastic. The plastic has unidirectionally fiber-reinforced plastic layers arranged one after the other. The unidirectionally fiber-reinforced plastic layers can form a laminate. The unidirectionally fiber-reinforced plastic layers preferably have exclusively unidirectionally oriented fibers. Furthermore, the unidirectionally fiber-reinforced plastic layers preferably have more than 80%, more than 90%, or more than 95% of the fibers oriented in one direction. The proportion of fibers in the main direction of extension of the plastic is preferably between 1% and 100%, particularly between 5% and 95%, and more preferably between 10% and 90%.

[0024] The thickness of the plastic can, for example, range between 0.5 mm and 8 mm, especially between 4 mm and 5 mm.

[0025] The fibers of the unidirectional fiber-reinforced plastic layers are designed as continuous fibers. These continuous fibers result in particularly high strength of the front cover unit, while still ensuring the required light transmission. The term "fibers" can generally be understood as reinforcing elements, such as ribbons.

[0026] It is preferred that the back side of the photovoltaic unit is formed by a glass plate or a film. Furthermore, the back side of the photovoltaic unit can be formed by and / or incorporate a plastic substrate.

[0027] The fiber volume fraction of the fiber-reinforced plastic layers is preferably between 1 and 50 volume percent, preferably between 5 and 40 volume percent, and particularly preferably between 10 and 30 volume percent.

[0028] A preferred embodiment of the photovoltaic unit is characterized by the fact that the front cover unit and the capsule material are in direct contact with each other. Preferably, no further component and / or means is arranged between the front cover unit and the capsule material. It is preferred that the interface between the front cover unit and the capsule material is designed such that the composite of cover unit and capsule material is substantially transparent to light energy. In particular, it may be preferred that there is no air gap, air inclusions, or the like between the front cover unit and the capsule material.In a further preferred embodiment of the photovoltaic unit, it is provided that the fibers have a fiber length that corresponds to more than 50%, preferably more than 75%, preferably more than 90%, and in particular 100%, of an extension of the front cover unit in the lateral direction and / or in the main extension direction.

[0029] The plastic can comprise two or more unidirectionally fiber-reinforced plastic layers arranged next to each other. It is preferred that at least one of the unidirectionally fiber-reinforced plastic layers is aligned parallel to the main direction of extension of the electrical connector. Furthermore, preferably two or more of the unidirectionally fiber-reinforced plastic layers are aligned parallel to the main direction of extension of the electrical connector.

[0030] A unidirectional fiber-reinforced polymer layer is understood to be, in particular, a polymer layer that comprises fibers and a matrix, where the fibers are essentially aligned in a single direction. The fibers are assumed to be ideally parallel and / or homogeneously distributed, although this assumption is theoretical, as deviations from this are regularly observed in practice because an ideal alignment and distribution are not practically achievable. Unidirectional fiber-reinforced polymer layers can, for example, be transversely isotropic.

[0031] The fibers within the plastic can be distributed evenly or unevenly in a targeted manner.

[0032] The fibers of at least one of the unidirectional fiber-reinforced plastic layers are aligned parallel to the main direction of extension of the electrical connector. Preferably, two or more of the unidirectional fiber-reinforced plastic layers are aligned parallel to the main direction of extension of the electrical connector. This has the particular advantage that the front cover unit exhibits high stiffness and low thermal expansion in the direction of the electrical connector, so that the aforementioned temperature fluctuations do not lead to an expansion of the photovoltaic unit that would permanently damage the electrical connector. The fact that the fibers of the unidirectional fiber-reinforced plastic layer are aligned parallel to the main direction of extension of the electrical connector means, in particular, that they are aligned parallel to the main direction of extension at least in certain sections.Naturally, due to manufacturing tolerances or design constraints, deviations from parallelism will occur in individual sections. Specifically, this means that parallelism between the fibers and the electrical connector must exist along more than 60%, more than 70%, more than 80%, more than 90%, or more than 95% of the length of the connector.

[0033] That the fibers of the unidirectionally fiber-reinforced plastic layer are aligned parallel to the main direction of extension of the electrical connector preferably means that the fibers and the main direction of extension of the electrical connector enclose a fiber angle of < 20°, < 15°, < 10°, < 5°, in particular < 2.5° with each other.

[0034] The extension(s) of the front cover unit are, in particular, those extensions that correspond to the planar extent of the front cover unit. In other words, these are, in particular, the lateral extensions. Specifically, the extension(s) are oriented orthogonally to a thickness of the front cover unit.

[0035] The greater the fiber length in relation to the extent of the front cover unit, the more robust the front cover unit becomes. Consequently, the thermal expansion of the front cover unit is reduced, resulting in greater resistance to such expansion with increasing fiber length, thus providing reliable protection against damage to the electrical connector.

[0036] In a further preferred embodiment of the photovoltaic unit, the fibers are or comprise glass fibers and / or carbon fibers. It is further preferred that the fibers are substantially translucent and / or transparent. In another preferred embodiment of the photovoltaic unit, the ratio of the first refractive index of the fibers to the second refractive index of the plastic is between 0.5 and 1.5, particularly between 0.75 and 1.25. Such ratios enable particularly advantageous operation of the photovoltaic unit.

[0037] In a preferred embodiment of the photovoltaic unit, the plastic is further specified as a fiber-reinforced thermoplastic. This means, in particular, that the matrix of the unidirectionally fiber-reinforced plastic layers is made of or contains a thermoplastic. Alternatively, the plastic can be a fiber-reinforced thermoset.

[0038] In another preferred embodiment, the unidirectionally fiber-reinforced plastic layers are designed as unidirectionally fiber-reinforced tapes. These materials, also known as UD tapes, offer several advantages. In particular, the individual tapes, and thus the individual fiber orientations, can be precisely predefined and then positioned during the manufacturing of the front cover unit. For example, sections where greater thermal expansion is expected can be made stronger by appropriately arranging the tapes. It has also proven particularly advantageous that unidirectionally fiber-reinforced tapes, especially thermoplastic unidirectionally fiber-reinforced tapes, allow for exceptionally good light transmission.

[0039] The thickness of the fiber-reinforced tapes can be, for example, 0.1 to 1 mm, preferably between 0.15 and 0.75 mm, particularly preferably between 0.2 and 0.5 mm.

[0040] It is further preferred that the unidirectional fiber-reinforced tapes are arranged such that 50% of the fibers are aligned in the 0° direction, 15% of the fibers in the +45° direction, 15% of the fibers in the -45° direction, and 20% of the fibers in the 90° direction. It may also be preferred that the unidirectional fiber-reinforced tapes are arranged such that 25% of the fibers are aligned in the 0° direction, 25% of the fibers in the +45° direction, 25% of the fibers in the -45° direction, and 25% of the fibers in the 90° direction. Furthermore, it may also be preferred that the unidirectional fiber-reinforced tapes are arranged such that 50% of the fibers are aligned in the 0° direction and 50% of the fibers in the 90° direction. Furthermore, it may be preferred that the unidirectional fiber-reinforced tapes are arranged such that 100% of the fibers are aligned in the 0° direction or in the 90° direction.A 0° direction preferably corresponds to the main direction of extension. Furthermore, it may be preferred that the plastic has at least one fiber-free plastic layer.

[0041] In another preferred embodiment of the photovoltaic unit, the front cover is curved. Furthermore, the capsule material containing the photovoltaic elements is preferably curved in the same way as the front cover. The plastic front cover has the particular advantage that it can be manufactured curved with minimal effort, thus offering an advantage over glass covers.

[0042] In another preferred embodiment of the photovoltaic unit, the unit is designed without a frame. Alternatively, it may be preferred that the photovoltaic unit has a frame made of unidirectionally fiber-reinforced tapes.

[0043] It is further preferred that the photovoltaic unit has no support element. This is made possible by the front cover unit.

[0044] According to another aspect, the aforementioned task is solved by a photovoltaic system comprising a mounting device for arranging photovoltaic units and a multitude of photovoltaic units according to at least one of the previously mentioned design variants, which are arranged on the mounting device.

[0045] According to a further aspect, the aforementioned problem is solved by a method for manufacturing a photovoltaic unit, in particular a photovoltaic unit according to one of the embodiments mentioned above, comprising the steps of: connecting at least two photovoltaic elements with an electrical connector, embedding the at least two photovoltaic elements within a capsule material, arranging a front cover unit that covers the capsule material and forms a front face of the photovoltaic unit, wherein the front cover unit comprises a plastic or the front cover unit consists of a plastic, wherein the plastic has unidirectionally fiber-reinforced plastic layers arranged one after the other, wherein fibers of at least one of the unidirectionally fiber-reinforced plastic layers are aligned parallel to the main direction of extension of the electrical connector, and wherein the fibers are designed as continuous fibers.

[0046] For further advantages, design variants and design details of the individual aspects and their possible further training, reference is also made to the description of the further aspects, the corresponding characteristics and further training.

[0047] Preferred embodiments are explained by way of example with reference to the accompanying figures. These show:

[0048] Figure 1: a schematic, three-dimensional view of an exemplary

[0049] Design of a photovoltaic system;

[0050] Figure 2: a schematic, two-dimensional view of an exemplary

[0051] Design of a photovoltaic unit;

[0052] Figure 3: a schematic, two-dimensional view of an exemplary

[0053] Design of a photovoltaic unit;

[0054] Figure 4: a schematic, two-dimensional view of an exemplary

[0055] Design of a photovoltaic unit;

[0056] Figure 5: a schematic, two-dimensional view of an exemplary

[0057] Design of a front cover unit;

[0058] Figure 6: a schematic, two-dimensional view of an exemplary

[0059] embodiment of two adjacent photovoltaic units; and

[0060] Figure 7: a schematic view of an exemplary process. In the figures, identical or essentially functionally equivalent or similar elements are designated with the same reference symbols.

[0061] The exemplary embodiments described below are preferred embodiments of the invention. In these exemplary embodiments, the described components each represent individual features of the invention that can be considered independently of one another. These features further develop the invention independently and can therefore be regarded as part of the invention individually or in a combination other than that shown. Furthermore, the described embodiments can also be supplemented by other features of the invention already described.

[0062] Figure 1 shows an exemplary embodiment of a photovoltaic system 1 comprising a plurality of photovoltaic units 4-20 arranged on a mounting device 2. The photovoltaic units 4-20 can, for example, be designed analogously to the photovoltaic units 100 described below.

[0063] Figures 2 to 4 show exemplary embodiments of a photovoltaic unit 100, which extends horizontally from a first side 101 to a second side 102. Perpendicular to this, the photovoltaic unit 100 extends from a front 103 to a back 104. In normal operation, the front 103 faces the schematically depicted sun. The front 103 is formed by a front cover unit 116.

[0064] On the side of the cover unit 116 facing away from the front 103, a capsule material 114 is provided in which two photovoltaic elements 106, 108 are embedded. Also embedded in the capsule material 114 is an electrical connector 110, which electrically connects the photovoltaic elements 106, 108 to each other. The electrical connector 110 has a main direction of extension 112, which is aligned in particular between the first side 101 and the second side 102.

[0065] The front cover unit 116 is essentially formed by a plastic 118. The plastic 118 has unidirectionally fiber-reinforced plastic layers 119, 119', 119" arranged one above the other, each having a matrix and fibers 120, 120', 120". The fibers 120, 120" of the unidirectionally fiber-reinforced plastic layers 119, 119" are oriented parallel to the

[0066] The main direction of extension 112 of the electrical connector 110 is aligned. The fibers 120' of the unidirectional fiber-reinforced plastic layer 119' are aligned orthogonally to the main direction of extension 112 of the electrical connector 110. The fibers 120, 120', 120" are designed as continuous fibers.

[0067] The electrical connector 110 extends through first sections 132 and a second section 134. In the first sections 132, the electrical connector 110 extends parallel to the main direction of extension 112. In the second section 134, the direction of extension of the electrical connector 110 changes over a short section into a vertical direction.

[0068] Figure 2 shows that the back side 104 of the photovoltaic unit 100 is formed by a support element 122. Figure 3 shows that the back side 104 is formed by a film 124. Figure 4 shows that the back side 104 is formed by a glass plate 126.

[0069] Figure 5 shows a schematic representation of the front cover unit 116. The extension between the first side 101 and the second side 102 is perpendicular to the plane of the image in Figure 5. It is shown that the fibers 120, 120" of the plastic layers 119, 119" are oriented essentially in the same direction, namely in the principal extension direction 112, which is also perpendicular to the plane of the image. The fibers 120' of the plastic layers 119' are oriented orthogonally to the principal extension direction 112 and to the orientation of the fibers 120, 120"

[0070] Figure 6 shows a schematic, two-dimensional view of an exemplary embodiment of two adjacent photovoltaic units 100. Each photovoltaic unit 100 comprises a plurality of photovoltaic elements, for which two photovoltaic elements 106, 108 are designated by reference numerals. The 16 photovoltaic elements 106, 108 of each photovoltaic unit 100 are connected in series with the electrical connector 110, the main direction 112 of the electrical connector 110 coinciding with the direction of the series connection. The fibers 120 of the front cover unit 116, not shown here, are at least partially aligned parallel to the main direction 112.

[0071] Figure 7 shows an exemplary process for manufacturing a photovoltaic unit. The process comprises step 200: connecting at least two photovoltaic elements 106, 108 with an electrical connector 110. Furthermore, the process comprises step 202: embedding the at least two photovoltaic elements 106, 108 within the capsule material 114.

[0072] Furthermore, the procedure includes step 204: arranging the front cover unit 116, which covers the capsule material 114 and forms a front face 103 of the photovoltaic unit 100.

[0073] The front cover unit 116 comprises the plastic 118, which has the unidirectionally fiber-reinforced plastic layers 119, 119', 119" with the fibers 120, 120', 120" embedded within it. The fibers 120, 120', 120" of at least one of the unidirectionally fiber-reinforced plastic layers 119, 119', 119" are aligned parallel to the main direction 112 of the electrical connector 110. Furthermore, the fibers 120, 120', 120" are configured as continuous fibers.

[0074] The photovoltaic unit 100 described above has the advantage of a front surface made of a plastic 118 with unidirectionally fiber-reinforced plastic layers 119, 119', 119" and thus exhibits both low weight and high durability. This is achieved because, despite fluctuating heat loads on the photovoltaic unit 100, essentially no differential expansion occurs within the unit. This is made possible in particular by the fact that at least some of the fibers 120, 120', 120" of the front cover unit 116 are aligned parallel to the main direction of extension 112 of the electrical connector 110. Therefore, the front cover unit 116 exhibits high strength in the direction of the electrical connector 110, which prevents damage to the electrical connector 110 even when the photovoltaic unit 100 is subjected to high heat loads.This results in a generally better, lighter, and more durable photovoltaic unit 100. REFERENCE MARK.

[0075] 1 photovoltaic system

[0076] 2 Mounting device

[0077] 4 photovoltaic units

[0078] 6 photovoltaic units

[0079] 8 photovoltaic units

[0080] 10 photovoltaic units

[0081] 12 photovoltaic units

[0082] 14 photovoltaic units

[0083] 16 photovoltaic units

[0084] 18 photovoltaic units

[0085] 20 photovoltaic units

[0086] 100 photovoltaic units

[0087] 101 first page

[0088] 102 second page

[0089] 103 Front

[0090] 104 Back

[0091] 106 photovoltaic element

[0092] 108 photovoltaic elements

[0093] 110 electrical connectors

[0094] 112 Main direction of extension of the electrical connector

[0095] 114 Capsule material

[0096] 116 front cover unit

[0097] 118 plastic 119, 119', 119" unidirectional fiber-reinforced plastic layers

[0098] 120, 120', 120" fibers

[0099] 122 Support element

[0100] 124 Foil 126 Glass plate

[0101] 132 first section

[0102] 134 second section

Claims

REQUIREMENTS 1. Photovoltaic unit (100) for providing electrical energy, comprising at least two photovoltaic elements (106, 108) connected by an electrical connector (110), wherein the electrical connector (110) has a main extension direction (112), a transparent capsule material (114) within which the at least two photovoltaic elements (106, 108) are embedded, a front cover unit (116) covering the capsule material (114) and forming a front (103) of the photovoltaic unit (100), - wherein the front cover unit (116) comprises a plastic (118) or the front cover unit (116) consists of a plastic (118), - wherein the plastic (118) has at least one unidirectionally fiber-reinforced plastic layer (119, 119', 119"), - wherein fibers (120, 120', 120") of the unidirectionally fiber-reinforced The plastic would lie (119, 119', 119") parallel to the main extension direction (112) of the electrical connector (110) are aligned, and - wherein the fibers (120, 120', 120") are formed as continuous fibers.

2. Photovoltaic unit (100) according to the preceding claim, wherein the front cover unit (116) and the capsule material (114) are directly adjacent to each other.

3. Photovoltaic unit (100) according to one of the preceding claims, wherein the fibers (120, 120', 120") have a fiber length which corresponds to more than 50%, preferably more than 75%, and further preferably more than 90% of an extent of the front cover unit (116) in the main extension direction (112).

4. Photovoltaic unit (100) according to any of the preceding claims, wherein the fibers (120, 120', 120") are or comprise glass fibers.

5. Photovoltaic unit (100) according to one of the preceding claims, wherein the ratio of a first refractive index of the fibers (120, 120', 120") and a second refractive index of the plastic (118) is between 0.5 and 1.5, in particular between 0.75 and 1.

25.

6. Photovoltaic unit (100) according to one of the preceding claims, wherein the plastic (118) is a fiber-reinforced thermoplastic.

7. Photovoltaic unit (100) according to one of the preceding claims, wherein the unidirectionally fiber-reinforced plastic layers (119, 119', 119") are designed as unidirectionally fiber-reinforced tapes.

8. Photovoltaic unit (100) according to one of the preceding claims, wherein the front cover unit (116) is curved.

9. Photovoltaic unit (100) according to one of the preceding claims, wherein the photovoltaic unit (100) is frameless.

10. Photovoltaic system (1) comprising a mounting device (2) for arranging photovoltaic units (100), and a plurality of photovoltaic units (4-20, 100) according to any one of the preceding claims 1-9, which are arranged on the mounting device (2).

11. Method for manufacturing a photovoltaic unit (100), in particular a photovoltaic unit (100) according to any one of the preceding claims 1-9, comprising the steps: - Connecting at least two photovoltaic elements (106, 108) with an electrical connector (110), Embedding the at least two photovoltaic elements (106, 108) within a capsule material (114), - Arranging a front cover unit (116) that covers the capsule material (114) and forms a front (103) of the photovoltaic unit, - wherein the front cover unit (116) comprises a plastic (118) or the front cover unit (116) consists of a plastic (118), - wherein the plastic (118) has unidirectionally fiber-reinforced plastic layers (119, 119', 119") arranged one after the other, - wherein fibers (120, 120', 120") of at least one of the unidirectionally fiber-reinforced plastic layers (119, 119', 119") are aligned parallel to the main direction of extension (112) of the electrical connector (110), and - wherein the fibers (120, 120', 120") are formed as continuous fibers.

Images