Method for producing photovoltaic roof panel

Abstract

The invention relates to a method for producing a photovoltaic roof panel comprising a roof panel (19) integrated with a photovoltaic module placed on an upper surface of the roof panel (19), wherein: a) a photovoltaic cell is placed in a solar cell laser cutting machine and cut into half cut cells; b) a first arrangement of at least two half cut cells is placed in a stringer machine and a second arrangement of the same number of half cut cells is placed in parallel, with the half cut cells of the second arrangement placed in a different direction than the half cut cells of the first arrangement; c) each of the half cut cell arrangements arranged in step b) is connected in series to form a cell string; d) two cell strings with opposite arrangement of half cut cells are connected with busbars to form a matrix (15) constituting a photovoltaic module intended for integration with the roof panel (19); e) the matrix (15) is applied in a negative pressure system to parts of the photovoltaic roof panel in an appropriately adapted shape, wherein these parts, viewed from top to bottom, are one by one as follows: a middle encapsulant film (16), a backsheet (17), the roof panel (19); f) at least one upper encapsulant film (14) and a glass pane (13) are applied to the system obtained in step e), on the matrix (15). The arrangement obtained in step f) is placed in a laminator containing an upper plate (21) and a lower plate (22), and then g) the laminator is vented; h) the upper plate (21) is lowered without applying pressure; i) the upper plate (21) is pressed against the panel using negative pressure and a vacuum is created in the laminator; j) cross-linking of encapsulants films (14, 16) is carried out. During the lamination process in the laminator, the arrangement obtained in step f) is pressed by the upper plate (21) and the lower plate (22), heating it from below and above, and wherein the lower plate (22) is fixed, while the upper plate (21) is lowered onto the panel placed on the lower plate (22).

Description

[0001] Method for producing photovoltaic roof panel

[0002] Technical field

[0003] The invention generally relates to the field of construction products used as roofing and photovoltaic roofing solutions. More specifically, the invention relates to a method for producing photovoltaic roofing composed of modular roof panels with an integrated photovoltaic cell configured for installation on a roof framework.

[0004] Background art

[0005] Polish patent application P.435257, filed by the Applicant of the present invention, discloses a modular roof panel comprising a body made of sheet metal and having a main plane comprising two transverse edges and two side edges, where the transverse edges have bends, one of which being bent downwards towards the lower surface, and the other being bent upwards towards the upper surface. The lower and upper bends form a so-called flat lock joint formed by joining the respective transverse edges of adjacent roof panels during roof installation, wherein the body together with the male leg, the female leg, the upper bend and the lower bend constitutes a completely prefabricated machine-stamped component. This solution allows complicated roofing operations that are performed manually to be reduced to a minimum.

[0006] Various types of photovoltaic panels mounted on existing roof coverings to convert solar energy into electricity are also known in the art. Such panels, however, disturb the original shape of the building and often protrude beyond its outline, which does not look attractive and negatively affects the aesthetics of the building. Traditional solar panels also require the installation of an additional support structure and usually an additional installation team, specializing in the installation of solar panels only, must be hired. Therefore, in practice, one team installs the roof covering and the other installs solar panels, which naturally translates into longer time and higher costs of performing such installation.

[0007] In view of the above, roof coverings with integrated photovoltaic cells have recently become more and more popular. Such products are attractive and appear virtually identical to a modular panel known in the art. Moreover, they can be installed on the roof by one installation team only that specializes in traditional roofing services.

[0008] In the present art, only metal roofing tiles with built-in photovoltaic elements are known. For example, one can mention patent application No. P.433999, filed by the Applicant of the present invention. The above-mentioned application relates to a roofing element in the form of a roof panel or metal roofing tile, wherein: a first layer of a higher temperature-activated polymer-based adhesive material is arranged on the upper surface; a photovoltaic element is located on the first layer of the adhesive material, the photovoltaic element being a photovoltaic cell fabricated using the monocrystalline technology; a second layer of the higher temperature-activated polymer-based adhesive material is arranged on the photovoltaic element; a transparent protective layer is arranged on the second layer of the adhesive material; wherein the first layer of the adhesive material, the photovoltaic element, the second layer of the adhesive material, and the transparent protective layer are joined with each other and with the body of the roofing element in the lamination process.

[0009] CN109831147A discloses a metal roofing tile comprising a base layer, a first adhesive layer, a photovoltaic cell layer, a second adhesive layer and a top layer.

[0010] During use, photovoltaic panels are constantly exposed to the adverse effects of changing weather conditions. Especially for this reason, photovoltaic cells should be tightly closed and secured. For this reason, it is desirable that photovoltaic roof coverings be manufactured using a lamination process that allows for ensuring sufficient panel tightness and increased mechanical resistance of the cell (through the use of a sheet metal backing). The lamination process protects photovoltaic cells and cables against vibrations and mechanical damage (e.g. by hailstones or objects). Moreover, thanks to an EVA film applied during lamination, the cell becomes resistant to high temperatures, humidity and dirt.

[0011] Standard laminators have a silicone sheet that falls off onto the panel. During the production process, air is sucked out using negative pressure, a vacuum is created and presses against the panel. However, the panel is heated only from the bottom, which may cause uneven temperature distribution and, consequently, incorrect lamination of the layers, as well as the formation of unfavourable stresses. This translates into increased risk of panel failure and shortening of its service life. Moreover, the lamination process in a standard laminator is very time-consuming - it takes about 40 minutes, which makes the process efficiency relatively low.

[0012] Summary of the invention

[0013] The objective of the present invention is to provide a method for producing a photovoltaic roof panel that will at least partially eliminate the disadvantages of the prior art.

[0014] The subject matter of the invention is a method for producing a photovoltaic roof panel comprising a roof panel integrated with a photovoltaic module placed on the upper surface of the roof panel, wherein: a) a photovoltaic cell is placed in a solar cell laser cutting machine and cut into half cut cells; b) at least two half cut cells are placed in a stringer machine for photovoltaic cells and connected in series to form a cell string; c) the same number of half cut cells as in step b) are placed in the stringer machine for photovoltaic cells and connected in series to form a cell string, wherein they are arranged parallel to the cell string produced in step b), but in a different direction than the half cut cells connected in step b); d) two cell strings with opposite arrangements of half cut cells, produced in steps b) and c), are connected with busbars to form a matrix, which is a photovoltaic module intended for integration with the roof panel; e) the matrix is applied in a negative pressure system to parts of the photovoltaic roof panel in an appropriately adapted shape, wherein these parts, viewed from top to bottom, are one by one as follows: a middle encapsulant film, a backsheet, the roof panel; f) at least one upper encapsulant film and a glass pane are applied, from the matrix side, to the arrangement obtained in step e); wherein the arrangement obtained in step f) is placed in a laminator comprising an upper plate and a lower plate, and then g) the laminator is vented; h) the upper plate is lowered, without applying pressure; i) a vacuum is created in the laminator, which results, inter alia, in pressing the upper plate against the panel using negative pressure; j) cross-linking of the encapsulants is carried out, wherein, during the lamination process in the laminator, the arrangement obtained in step f) is pressed by the upper plate and the lower plate, heating said arrangement from below and above, and wherein the lower plate is fixed, while the upper plate is lowered onto the panel placed on the lower plate.

[0015] Preferably, the laminator plates are provided with heating elements grouped into three heating sections: a front section A, a middle section B, and a rear section C.

[0016] Preferably, eighteen half cut cells are placed in a stringer machine for photovoltaic cells to obtain a cell string consisting of eighteen half cut cells.

[0017] Preferably, the venting of the laminator in step g) takes 10 seconds.

[0018] Preferably, after the upper laminator plate has been lowered without applying pressure in step h), it remains in this position for 160 seconds.

[0019] Preferably, it takes 20 seconds to produce a vacuum by pressing the upper plate using negative pressure in step i).

[0020] Preferably, the negative pressure value in the laminator is 650 mbar.

[0021] Preferably, after the upper plate has been pressed, the pressure of the upper plate is maintained at atmospheric pressure, preferably for 150 seconds.

[0022] Preferably, the lamination process in the laminator takes maximum of 11 minutes.

[0023] Preferably, in step e) a back encapsulant film is placed between the backsheet and the roof panel.

[0024] Preferably, after the cross-linking of the encapsulant films, the edges of the panel are sealed in the laminator, preferably by melting the encapsulant films.

[0025] Preferably, a junction box is connected to the busbars running from the matrix through a hole in the roof panel.

[0026] Preferably, silicone is applied around the junction box and the wires are soldered to the contacts, then the whole thing is filled with potting material, preferably in amount of 6 ml.

[0027] Preferably, the photovoltaic cell is fabricated using the busbar technology.

[0028] Preferably, the encapsulant film is an EVA film. Advantageous effects of the invention

[0029] The lamination process of the invention takes about 11 minutes, which is almost four times shorter than in standard laminators known in the art. This allows for an almost fourfold increase in the efficiency of the production line. Further, in the process of the invention, the laminator is provided with two aluminium plates that fall onto the panel, whereby the panel is heated both from above and below. In a standard laminator, the heating occurs only from below, which creates the risk of incorrect lamination of layers and development of stresses. Therefore, the method according to the invention allows for controlled distribution of the laminator operating temperature, which contributes to the correct lamination of the layers and allows for controlled material relaxation after the thermal process. The laminator used in the method of the invention also has a vacuum storage tank. Due to this solution, the vacuum is produced earlier, which allows the air to be sucked out faster after opening the valves, and then the upper plate of the laminator to be pressed to the panel using negative pressure.

[0030] Brief description of the Drawings

[0031] The subject matter of the invention is a method for producing a photovoltaic roof panel constructed by integrating the roof panel with a photovoltaic module placed on its upper surface. The roof panel alone is shown in the attached drawings, wherein:

[0032] Fig. 1 - shows a modular roof panel in a perspective view;

[0033] Fig. 2 - shows a roof panel in a side projection;

[0034] Fig. 3 - shows a more detailed perspective view of the roof panel;

[0035] Fig. 4 - shows a partial top view of the roof panel;

[0036] Fig. 5 - shows a flat lock joint of the upper and lower bends of adjacent roof panels;

[0037] Fig. 6 - shows a roof panel in a top projection with visible locks and seal between the upper bend and the male and the female legs;

[0038] Fig. 7 - shows the first lock and the second lock in detailed views;

[0039] Fig. 8 - shows a flat lock joint in a perspective view;

[0040] Fig. 9 - shows a snap lock joint in a cross section view; Fig. 10 - shows a roof panel in a bottom view;

[0041] Fig. 11 - shows a roof panel in a bottom view with a noise attenuation layer;

[0042] Fig. 12 - shows a cross section through a photovoltaic panel before connection to the junction box;

[0043] Fig. 13 - shows a cross section through a photovoltaic panel after connection to the junction box;

[0044] Fig. 14 - shows the system placed between the laminator plates and the schematic arrangement of sections A, B, C of the laminator plates;

[0045] Fig. 15 - shows a photovoltaic panel in a top view.

[0046] Detailed description

[0047] The subject matter of the invention is a method for producing a photovoltaic roof panel that can be combined into a modular photovoltaic roofing system containing many modular roof panels made of sheet metal configured to create a roofing fastened to the roof framework, which photovoltaic roof panel comprises a roof panel integrated with a photovoltaic module located on the upper surface of this roof panel.

[0048] In order to better understand the invention, first of all, an embodiment of a roof panel alone will be described, in accordance with the solution developed by the Applicant. Such a panel is shown in Figs. 1-11.

[0049] The modular roof panel 19 is composed of a four-sided body 1 which is made of sheet metal. The sheet metal is made of steel (preferably low-elasticity steel) or other metals or metal alloys, such as aluminium, copper or zinc. As shown in Fig. 1, the body 1 comprises an upper surface 2 and a lower surface 3. Further, the body 1 has an upper side 5a, a lower side 5b, a left side 4a and a right side 4b. The lower and upper surfaces 2 and 3 are preferably flat. Alternatively, they may be corrugated or include a plurality of longitudinal ribs running equidistantly parallel to the side edges.

[0050] The left side 4a and the right side 4b are shaped into a so-called snap lock seam, shown, for example, in Figs. 3 and 4. For this purpose, the left side 4a is formed into a male leg 9, and the right side 4b is formed into a female leg 8 - together they form a snap lock joint that is created by joining the respective sides of the adjacent roof panels 19 to snap together without the need of bending the sheet metal - the snap lock joint is shown in more detail in Fig. 9 and will be described below.

[0051] The male leg 9 has a first standing wall connected integrally to the body 1, i.e. a wall raised upwards with respect to the upper surface 2. In the presented example, the first standing wall extends obliquely upwards and at an obtuse angle with respect to the upper surface 2. The first standing wall has also a longitudinally extending snap lock socket created by bending a fragment of the first standing wall into a characteristic hump extending away from the second standing wall towards the upper surface 2. The snap lock socket receives the engaging element of the female leg 8 to form a snap lock joint. The first standing wall then turns into a second standing wall which is also raised upwards with respect to the upper surface 2. In the presented example, the second standing wall extends obliquely at an acute angle to the upper surface 2. The second standing wall is terminated with a mounting strip with a plurality of openings used for fixing the modular roof panel with screws to the roof support structure or to the previously made roof boarding on which the roof covering is installed. The mounting strip extends substantially parallel to the main plane of the body.

[0052] The female leg 8 has a first standing wall integrally connected to the body 1. The first standing wall is raised upwards and extends obliquely at an obtuse angle to the upper surface 2. The first standing wall then turns into a second standing wall which is raised upwards and extends obliquely at an acute angle to the upper surface 2. This second standing wall has an engaging element which is pressed into the snap lock socket of the male leg 9 to form a snap lock joint. The engaging element is formed as an end edge of the second standing wall folded inwardly towards the first standing wall. For example, the engaging element may have the form of a hook or a lip extending over the entire length of the second standing wall.

[0053] The male leg 9 and the female leg 8 have at their ends, in the area of the upper bend 6, locks 11a and lib to facilitate joining of the adjacent roof panels 19 - this is shown in more detail in Fig. 6 and Fig. 7. The first lock 11a is formed by a cut-out made at the end section of the male leg 9, wherein this cut-out is created by removing a fragment of the entire second standing wall together with the entire fragment of the mounting strip of the same length. This cut-out is made with a length equal to at least the sum of the widths of the upper bend 6 and the lower bend 7. The second lock lib is formed by a cut-out made at the end section of the female leg 8, this cut-out being formed by removing a fragment of a part of the second standing wall along its longer edge. The length of the cut-out forming the second lock lib is equal to or greater than the width of the upper bend 6. The use of locks makes it easier to hook the upper bend 6 and lower bend 7 of two adjacent roof panels 19 over each other to form a flat lock joint before the snap lock joint between the male leg 9 and the female leg 8 is created.

[0054] The upper side 5a and the lower side 5b have bends - as seen, for example, in Figs. 2-6. The lower side 5b has a lower bend 7 bent downwards, i.e. under the bottom of the lower surface 3, and the upper side 5a has an upper bend 6 which is bent upwards and extends over the upper side of the surface 2. In the presented example, the upper bend 6 and the lower bend 7 comprise a first section with semicircular cross section and a second straight section connected thereto, extending substantially parallel to either the plane of the body or the upper and lower surfaces 2 and 3, respectively.

[0055] The upper bend 6 and the lower bend 7 form a so-called flat lock joint. This joint is shown in detail in Fig. 5.

[0056] To facilitate the creation of a flat lock joint, the longer edge of either the upper bend 6 or the lower bend 7, preferably the lower bend 7, extends obliquely for at least a part of its length. In a preferred embodiment, this edge runs obliquely over its entire length between the male leg 9 and the female leg 8 (see Fig. 10). Also preferably, when the longer edge of the lower bend 7 is oblique, the longer edge of the upper bend 6 extends perpendicular to the left side 4a and the right side 4b. It is also possible for both long edges of both the upper bend 6 and the lower bend 7 to run obliquely at the same time. The obliquely shaped bend causes that when connecting two roof panels 19 together, the force needed to hook the upper bend 6 of one roof panel 19 to the lower bend 7 of the second roof panel 19 is in the initial phase smaller and gradually increases until a strong and stable flat lock joint is achieved, because the contact surface between the bends is relatively small in the initial phase and increases as the two bends overlap each other.

[0057] The modular roof panel 19 has a seal 10 to prevent water penetration into the flat lock joint (prevents water capillary rise). The seal is provided in the area of at least one of the bends. It may have the form of a flexible seal or a sealing mass. A preferred example of the seal 10 is shown in Figs. 3, 4 and 6. The seal 10 is made of a special sealing mass in the gaps between the upper bend 6, and the male leg 9 and the female leg 8, and specifically between the shorter edge of the upper bend 6 and the first standing wall of the male leg 9 and the female leg 8. In order not to damage the seal 10 during the joining operation of the adjacent roof panels 19, the corners of the lower bend 7 can be are chamfered or rounded.

[0058] Such a modular roof panel comprising a body 1 together with a male leg 9, a female leg 8, an upper bend 6 and a lower bend 7, as well as locks 11a, lib, is entirely machine produced as a prefabricated element, profiled and bent with a dedicated machine. Preferably, the seal 10 or an optional noise attenuation layer 12 that is attached to the lower surface 3 (Fig. 11) are produced also in this step.

[0059] A method of producing a photovoltaic roof panel which comprises the above-described roof panel 19 integrated with a photovoltaic module located on the upper surface of the roof panel 19, will be described below.

[0060] The photovoltaic roof panel is manufactured using a laminator having a vacuum storage tank. A 12BB photovoltaic cell is preferably used to fabricate the panel. The abbreviation "BB" comes from English language and means a "BusBar". Busbars are connectors running vertically through silicon cells, responsible for collecting energy from the cells. In other words, the busbars can be referred to as current buses, but in the commonly used nomenclature the former term (busbars) is used. In the further part of the specification, the tern "busbars" will be used. Twelfe busbars are used to produce 12BB photovoltaic cells, which allows to increase the efficiency of the entire system and enables higher output power, which translates into greater power obtained from a single photovoltaic panel (the efficiency of 12BB photovoltaic cells is higher than of those made using the 9BB or 5BB technology). Such photovoltaic cells divided into smaller portions are more resistant to overloads and unfavourable weather conditions, and thus to cracks and other mechanical damage. In photovoltaic panels fabricated using this technology, the busbars are smaller than in traditional modules, which shortens the transmission distance and reduces the loss of resistance. A larger number of busbars reduce the spacing between busbars, which shortens the path of the flowing current, which neutralises the energy losses resulting from resistance. The 12BB technology used in half cut cell modules additionally helps to neutralise the shading of individual module elements. This increases the efficiency of the module's operation in poor conditions.

[0061] In a method according the the invention, first of all a photovoltaic cell, preferably a 12BB photovoltaic cell, preferably a square-shaped one with chamfered corners with dimensions of 210 / 210 mm, is placed in a cell cutting station.

[0062] The photovoltaic cell is placed in a laser cell cutting machine for photovoltaic cells and cut into rectangles, constituting half cut cells - a single half cut cell is a module with cells cut in half.

[0063] In the next step, the half cut cells are placed in a stringer machine for automatic connection of photovoltaic cells, where the soldering process takes place. In the industry nomenclature, this machine is referred to as a stringer.

[0064] In the soldering process, a single cell string is created using an appropriate number of half-cut cells, in the embodiment - eighteen.

[0065] A cell string is a separate electrical circuit consisting of photovoltaic panels connected in series, in the embodiment - of eighteen. This method of assembling modules results in the voltage at the terminals of a cell string being the total value (sum) of the voltages of all panels in the circuit.

[0066] The resulting cell string is transferred to the next station, and the next eighteen half cut cells are arranged parallel tothe already created cell string in a different direction than the previous ones, so that one cell string is turned with its bevels facing one side and the other cell string is turned with its bevels facing the other, opposite side.

[0067] In the next step, the resulting two cell strings - with opposite arrangements of half cut cells - are connected with busbars in the soldering process.

[0068] After the soldering process is completed, a so-called matrix 15 is created, constituting a photovoltaic module, which is then integrated with the roof panel 19.

[0069] Fig. 12 and Fig. 13 show a cross section through the layers of the finished photovoltaic roof panel, wherein Fig. 12 shows a cross section through the photovoltaic roof panel before connecting the junction box 20, and Fig. 13 shows a cross section through the photovoltaic roof panel after connecting the junction box 20 to it through the opening in the roof panel 19. After the soldering process is completed, the matrix 15 (photovoltaic cells connected in cell strings, cell strings connected in a matrix 15) is transferred to the second part of the production line, which contains, one by one, the following parts of the photovoltaic roof panel in an appropriately adjusted shape. These are, one by one, from the top: a middle encapsulant film 16 (cutting off UV radiation); a backsheet 17, preferably made of a polymer or a combination of polymers; a back encapsulant film 18 (cutting off UV radiation), the roof panel 19. The back encapsulant film 18 is optional and does not have to be used in another embodiment.

[0070] In the negative pressure system, the matrix 15 is placed on the above-mentioned parts.

[0071] At the next station, another upper encapsulant layer 14 (at least one, and preferably two) is placed on the matrix 15, followed by glass 13, whereby a photovoltaic panel is produced.

[0072] The encapsulants 14, 16, 18 in the embodiment are EVA films, but in other embodiments they may be made of a material other than EVA.

[0073] Busbars, to which the junction box 20 is later attached, pass from the matrix 15, through the cut-out (hole) in the roof panel 19 (and in the backsheet 17, or also the encapsulant 18).

[0074] Then, the arrangement prepared in this way, i.e. the unlaminated photovoltaic roof panel, goes to the quality control station (the so-called EL-TEST). At the quality control station it is checked, for example, if the cells have been broken. If the quality control finds an element defective, it is sent to the repair station (for material recovery). If, however, the tests are positive, the produced panel goes to the laminator.

[0075] After placing the above arrangement in the laminator, the first step is to vent the laminator, preferably for 10 seconds. The upper plate 21 of the laminator is then lowered, without applying any pressure, and this condition lasts preferably for 160 seconds. The bottom plate 22 of the laminator is fixed. The arrangement is placed on said lower plate 22 by a feeder. The arrangement placed between the laminator plates is shown in Fig. 14.

[0076] After lowering the upper plate of the laminator, a vacuum is created by pressing the upper plate 21 against the arrangement using negative pressure. This takes preferably 20 seconds. The negative pressure value in the laminator is preferably 650 mbar. Then, for preferably 150 seconds, the pressure of the upper plate 21 is maintained at atmospheric pressure.

[0077] Afterthe specified time has elapsed, the encapsulants 14, 16, 18 melted in the previous phases (lamination phases) are hardened - the so-called cross linking of encapsulants.

[0078] The plates (upper 21 and lower 22) of the laminator are provided with heaters allowing to maintain the desired temperature during the lamination process. To enable control of the lamination process, the heaters are grouped into A / B / C sections, which can be controlled separately. The laminator plates 21, 22 are divided proportionally into sections: front A, middle B and rear C. The schematic arrangement of the laminator sections is shown in Fig. 14.

[0079] The temperatures of each heating section of the laminator are selected in the range from 100°C do 200°C.

[0080] After the lamination process performed in the laminator, a finished photovoltaic roof panel is obtained, constituting a single element.

[0081] The entire lamination process in the laminator, as described above, takes about 11 minutes, which is almost four times shorter than in standard laminators known in the art.

[0082] As mentioned above in the background art section, a standard laminator has a sheet of silicone that falls off onto the photovoltaic panel. During the negative pressure process, air is sucked out, vacuum is created and the panel is pressed against it.

[0083] The laminator used in the method of the invention, specially designed for this purpose, has two aluminium plates that press against the earlier arranged parts of the photovoltaic roof panel, wherein the heating is provided both from above and from below (in a standard laminator, the heating is provided from below only). The upper plate 21 of the laminator is profiled in a way that allows it to be placed between the side locks of the roof panel 19 on which the photovoltaic cells are placed. This method of operation allows for the controlled distribution of the laminator operating temperature, which contributes to the correct lamination of the layers and allows for the controlled relaxation of the material after the thermal process.

[0084] The laminator used in the method of the invention also has a vacuum storage tank. The base of the device comprises a tank from which the air is removed. After opening the valves, within a few seconds the pressure in the laminator chamber drops to a level close to vacuum. In a traditional membrane laminator using a flexible membrane that falls on the panel, the air is removed (sucked out) from the chamber using vacuum pumps, and this process lasts from a few to a dozen or so minutes, depending on the type of the membrane laminator. Due to the vacuum storage tank solution, the vacuum is created earlier, which allows the air to be sucked out faster after opening the valves and then pressing the upper plate 21 of the laminator to the panel using negative pressure.

[0085] After all laminator operation cycles have been completed (i.e. after a maximum of 11 minutes), the edges of the panel are sealed in the laminator. Under the action of temperature and vacuum, the excessive encapsulant film 14, 16, 18 (preferably EVA film) melts and acquires a gel / rubber consistency. As the film melts, it increases in volume, flows out and seals: a) in the upper part of the panel - the space between the glass and the panel surface b) in the side part of the panel - the space between the glass and the panel locks, sealing the edges.

[0086] Alternatively, after all laminator cycles have been completed, the photovoltaic panel can be moved to a station where silicone is applied to the long edges of the photovoltaic panel to seal it. Then the photovoltaic panel is placed in a string warehouse, where the silicone hardening takes place.

[0087] The finished panel after lamination is shown schematically in a top view in Fig. 15.

[0088] After laminating and sealing, the finished panel goes to a station where junction boxes 20 are installed. Each junction box is glued, for example, with silicone or another adhesive. Silicone is applied around the box and the busbars are soldered to the contacts, after which the whole thing is filled with potting material, preferably in amount of 6 ml. Finally, the whole thing is snapped with a cover. As a result of the process, the positioning of the junction box 20 has been moved below the border of the glass.

Claims

Claims1. A method for producing a photovoltaic roof panel comprising a roof panel (19) integrated with a photovoltaic module placed on an upper surface of the roof panel (19), wherein: a) a photovoltaic cell is placed in a solar cell laser cutting machine and cut into half cut cells; b) a first arrangement of at least two half cut cells is placed in a stringer machine and a second arrangement of the same number of half cut cells is placed in parallel, with the half cut cells of the second arrangement placed in a different direction than the half cut cells of the first arrangement; c) each of the half cut cell arrangements arranged in step b) is connected in series to form a cell string; d) two cell strings with opposite arrangement of half cut cells are connected with busbars to form a matrix (15) constituting a photovoltaic module intended for integration with the roof panel (19); e) the matrix (15) is applied in a negative pressure system to parts of the photovoltaic roof panel in an appropriately adapted shape, wherein these parts, viewed from top to bottom, are one by one as follows: a middle encapsulant film (16), a backsheet (17), the roof panel (19); f) at least one upper encapsulant film (14) and a glass pane (13) are applied to a system obtained in step e), on the matrix (15); characterised in that the arrangement obtained in step f) is placed in a laminator comprising an upper plate (21) and a lower plate (22), and then g) the laminator is vented; h) the upper plate (21) of the laminator is lowered without applying pressure; i) the upper plate (21) of the laminator is pressed against the panel using negative pressure and a vacuum is created in the laminator; j) cross-linking of encapsulant films (14, 16) is carried out; wherein, during the lamination process in the laminator, the arrangement obtained in step f) is pressed by the upper plate (21) and the lower plate (22) of the laminator, heating said arrangement from below and above, and wherein the lower plate (22) isfixed, while the upper plate (21) is lowered onto the panel placed on the lower plate (22).

2. The method according to claim 1, wherein the laminator plates (21, 22) are provided with heating elements grouped into three heating sections: a front section A, a middle section B and a rear section C.

3. The method according to claim 1 or 2, wherein eighteen half cut cells are placed in the stringer machine for photovoltaic cells to obtain a cell string consisting of eighteen half cut cells.

4. The method according to either claim 1 or 2 or 3, wherein the venting of the laminator in step g) takes 10 seconds.

5. The method according to any preceding claims, wherein after the upper plate (21) has been lowered without applying pressure in step h), it remains in this position for 160 seconds.

6. The method according to any preceding claims, wherein it takes 20 seconds to produce a vacuum by pressing the upper plate (21) using negative pressure in step i).

7. The method according to any preceding claims, wherein the negative pressure value in the laminator is 650 mbar.

8. The method according to any preceding claims, wherein after the upper plate (21) has been pressed, the pressure of the upper plate (21) is maintained at atmospheric pressure, preferably for 150 seconds.

9. The method according to any preceding claims, wherein the lamination process in the laminator takes maximum of 11 minutes.

10. The method according to any preceding claims, wherein in step e) a back encapsulant film (18) is placed between the backsheet (17) and the roof panel (19).

11. The method according to any preceding claims, wherein after the cross-linking of the encapsulant films (14, 16, 18), the edges of the panel are sealed in the laminator, preferably by melting the encapsulant films (14, 16, 18).

12. The method according to any preceding claims, wherein a junction box (20) is connected to the busbars running from the matrix (15) through a hole in the roof panel13. The method according to any preceding claims, wherein silicone is applied around the junction box (20) and the wires are soldered to the contacts, then the whole thing is filled with potting material, preferably in amount of 6 ml.

14. The method according to any preceding claims, wherein the photovoltaic cell is fabricated using the busbar technology.

15. The method according to any preceding claims, wherein the encapsulant film (14, 16, 18) is an EVA film.

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