Patent Publication Number: US-2018047863-A1

Title: Photovoltaic module

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2016-0102423, filed on Aug. 11, 2016, the contents of which is incorporated by reference herein in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to a photovoltaic module including a solar cell and having a curved surface. 
     2. Background of the Invention 
     A solar cell is configured to convert light energy into an electric energy. In general, a solar cell includes a P type semiconductor and an N type semiconductor, and when the solar cell receives light, electric charges migrate to cause a potential difference. 
     A photovoltaic module refers to a module having a solar cell to produce electric power from light. A module refers to a constituent unit of a machine or a system and indicates an independent unit assembled to several electronic components or mechanical components to have a specific function. Thus, the photovoltaic module may be understood as indicating an independent unit having a solar cell and having a function of producing electric power from light. 
     The photovoltaic module is applied to a roof of an automobile or an interior or exterior material of a building, electric power may be applied using 1) indoor light supplied from a fluorescent lamp or a light emitting diode (LED) or 2) natural light supplied from the sun, even without having to connect a separate power cable. Glass is disposed on an outermost layer of a photovoltaic module applied to a roof of an automobile or an interior or exterior material of a building, and here, the glass may have a curved surface due to a function, a design, and the like. 
     A solar cell formed of crystalloid may have flexibility to a degree, but a solar cell adhered to curved glass may be cracked in a corner portion. 
     Also, bubbles generated in the process of manufacturing a photovoltaic module may remain to act as a defect of a photovoltaic module. In addition, a solar cell module may move during a manufacturing process of a photovoltaic module to produce a product having a design different to an initial design. 
     SUMMARY OF THE INVENTION 
     Therefore, an aspect of the detailed description is to provide a structure in which a solar cell is not broken in a photovoltaic module having curved glass. 
     Another aspect of the detailed description is to provide a method for manufacturing a photovoltaic module eliminating generation of bubbles and movement of a solar cell during a manufacturing process of a photovoltaic module having a curved glass. 
     To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a photovoltaic module includes: a solar laminated assembly; a first glass adhered to one surface of the solar laminated assembly; a back sheet or second glass adhered to the other surface of the solar laminated assembly; and encapsulant layers adhering the first glass to the solar laminated assembly and adhering the back sheet or second glass to the solar laminated assembly. 
     A concept of the solar laminated assembly and a detailed configuration of the encapsulant layers may differ according to embodiments. Also, according to an embodiment, the photovoltaic module may selectively include films configured to protect the solar laminated assembly. 
     The photovoltaic module of the present disclosure may be classified into first to third embodiments depending on whether films are removed from the solar laminated assembly. A photovoltaic module of the first embodiment has a structure including a first film and a second film as films are not removed from the solar laminated assembly. A photovoltaic module of the second embodiment has a structure in which both a first film and a second film are removed from the solar laminated assembly. A photovoltaic module of the third embodiment has a structure in which only a first film is removed from the solar laminated assembly. 
     The photovoltaic module of the first embodiment may include: a solar laminated assembly including at least one solar cell having a first surface and a second surface in mutually opposite directions, first and second films disposed to cover the first and second surfaces, respectively, a first encapsulant layer disposed between the first surface and the first film to adhere the solar cell and the first film, and a second encapsulant layer disposed between the second surface and the second film to adhere the solar cell and the second film; a first glass having a curved surface and covering the first film; a back sheet or second glass covering the second glass; a third encapsulant layer disposed between the first film and the first glass to adhere the first film and the first glass; and a fourth encapsulant layer disposed between the second film and the back sheet to adhere the second film and the back sheet or disposed between the second film and the second glass to adhere the second film and the second glass. 
     The first to fourth encapsulant layers may be formed of a thermosetting resin or a thermoplastic resin. 
     The third encapsulant layer and the fourth encapsulant layer may be thicker than the first encapsulant layer and the second encapsulant layer. 
     The first film may be formed of a transparent material. The transparent material may be polyethylene terephthalate (PET), for example. 
     When the back sheet of the photovoltaic module is formed of a transparent material or when the photovoltaic module includes a second glass, the second film may be formed of a transparent material. The transparent material may be PET. When the back sheet of the photovoltaic module is black or white, the second film may have a color to strengthen visibility. 
     A photovoltaic module of the second embodiment may include: at least one solar cell having a first surface and a second surface in mutually opposite directions; a first glass having a curved surface and covering the first surface; a back sheet or second glass covering the second surface; a first encapsulant layer disposed between the first surface and the first glass to adhere the solar cell and the first glass; and a second encapsulant layer disposed between the second surface and the back sheet to adhere the solar cell and the back sheet or disposed between the second surface and the second glass to adhere the solar cell and the second glass. 
     The first encapsulant layer and the second encapsulant layer may be formed of a thermosetting resin, and which are stacked to form two layers. Among the two layers, a layer disposed to be relatively away from the solar cell may be thicker than a layer disposed to be relatively close to the solar cell. 
     The first encapsulant layer and the second encapsulant layer may include a first layer adhered to the solar cell; and a second layer adhered to the first glass or adhered to the back sheet or second glass. Any one of the first layer and the second layer may be formed of a thermosetting resin and the other may be formed of a thermoplastic resin. 
     A thickness of the first encapsulant layer and the encapsulant layer may range from 450 μm to 1,100 μm, and may be formed of a thermosetting resin. 
     The first encapsulant layer and the second encapsulant layer may be formed of a thermoplastic resin. 
     To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a method for manufacturing a photovoltaic module is provided. The photovoltaic module of the present disclosure is manufactured by previously manufacturing a solar laminated assembly through a first lamination process, and post-adhering a) a first glass and b) a back sheet or second glass to the solar laminated assembly. A detailed configuration may be varied according to embodiments. 
     The manufacturing method of the first embodiment may include: a first operation of manufacturing a solar laminated assembly having a structure in which a first encapsulant layer and a first film are sequentially stacked on a first surface of a solar cell and a second encapsulant layer and a second film are sequentially stacked on a second surface of the solar cell; and a second operation of adhering a first glass having a curved surface to a first surface of the solar laminated assembly and adhering a second glass having a curved surface to a back sheet of a second surface of the solar laminated assembly, wherein the first operation includes: sequentially stacking a first encapsulant layer and a first film on the first surface of the solar cell and sequentially stacking a second encapsulant layer and a second film on the second surface of the solar cell; and adhering the first film to the first surface of the solar cell and adhering the second film to the second surface of the solar cell through a first lamination process of applying heat to the first encapsulant layer and the second encapsulant layer, while pressing the first film and the second film in a direction toward each other. 
     The second operation may include: disposing a third encapsulant layer between the first film and the first glass and disposing a fourth encapsulant layer between the second film and the back sheet or between the second film and the second glass; and adhering the first glass to the first surface of the solar laminated assembly and adhering the back sheet or the second glass to the second surface of the solar laminated assembly through a second lamination process of applying heat and pressure within a hermetically closed chamber. 
     The first to fourth encapsulant layers may be formed of a thermosetting resin or a thermoplastic resin. 
     The first encapsulant layer and the second encapsulant layer may be thicker than the third encapsulant layer and the fourth encapsulant layer. 
     At least one of the first film and the second film may be formed of a transparent material. 
     A manufacturing method of the second embodiment may include: a process of removing the first film and the second film after the first lamination process in the first operation. Thereafter, a photovoltaic module may be completed through the second lamination process of the second operation. 
     In the first operation, a solar laminated assembly may be manufactured. The first operation may include: sequentially stacking a first encapsulant layer and a first film on a first surface of the solar cell and sequentially stacking a second encapsulant layer and a second film on a second surface of the solar cell; and adhering the first film to the first surface of the solar cell and adhering the second film to the second surface of the solar cell through the first lamination process of applying heat to the first encapsulant layer and the second encapsulant layer, while pressing the first film and the second film in a direction toward each other. 
     The manufacturing method of the second embodiment may include: removing the first film and the second film from the solar laminated assembly after the first operation. 
     The second operation may include: additionally disposing a second layer of the first encapsulant layer between a first layer of the first encapsulant layer exposed as the first film was removed and the first glass and additionally disposing a second layer of the second encapsulant layer between a first layer of the second encapsulant layer exposed as the second film was removed and the back sheet or between the first layer of the second encapsulant layer and the second glass; and adhering the first glass to the first surface of the solar laminated assembly and adhering the back sheet or the second glass to the second surface of the solar laminated assembly through a second lamination process of applying heat and pressure within a hermetically closed chamber. 
     The first layer of the first encapsulant layer and the first layer of the second encapsulant layer may be formed of a thermosetting resin or a thermoplastic resin, and the second layer of the first encapsulant layer and the second layer of the second encapsulant layer may be formed of a thermosetting resin. 
     In another manufacturing method of the second embodiment, a thermoplastic resin is included in the solar laminated assembly, and thus, an additional encapsulant layer for the second lamination process is not required in the second operation after removing the first film and the second film. This will be described hereinafter. 
     The first operation is performed to manufacture a solar laminated assembly. the first operation includes: sequentially stacking a first encapsulant layer and a first film on a first surface of a solar cell and sequentially stacking a second encapsulant layer and a second film on a second surface of the solar cell; and adhering the first film to the first surface of the solar cell and adhering the second film to the second surface of the solar cell through the first lamination process of applying heat to the first encapsulant layer and the second encapsulant layer, while pressing the first film and the second film in a direction toward each other. Here, the first encapsulant layer and the second encapsulant layer may be formed of a thermoplastic resin and may be configured as a single layer. Or, the first encapsulant layer and the second encapsulant layer may include a first layer adhered to the solar cell and a second layer adhered to a first glass or adhered to a back sheet or second glass, and any one of the first layer and the second layer may be formed of a thermosetting resin and the other may be formed of a thermoplastic resin. 
     The first layer may be formed of a thermosetting resin and may be disposed to cover the solar cell in the first operation. The second layer may be formed of a thermoplastic resin and may be disposed to cover the first layer in the second operation. 
     After the first operation, the first film and the second film may be removed from the solar laminated assembly. 
     The second operation may include adhering a first glass to a first surface of the solar laminated assembly and adhering a back sheet or second glass to a second surface of the solar laminated assembly through a second lamination process of applying heat and pressure within a hermitically closed chamber. Since the thermoplastic resin used as the first encapsulant layer and the second encapsulant layer of the solar laminated assembly is melted again and cured in the second lamination process, an additional encapsulant layer is not required in the second operation. 
     A manufacturing method of the third embodiment is distinguished from the first embodiment and the second embodiment described above, in that only a first film is removed after a first operation and a second operation is performed while a second film is maintained. Hereinafter, the manufacturing method of the third embodiment will be described. 
     The first operation may be performed to manufacture a solar laminated assembly. The first operation may include sequentially stacking a first encapsulant layer and a first film on a first surface of a solar cell and sequentially stacking a second encapsulant layer and a second film on a second surface of the solar cell; and adhering the first film to the first surface of the solar cell and adhering the second film to the second surface of the solar cell through the first lamination process of applying heat to the first encapsulant layer and the second encapsulant layer, while pressing the first film and the second film in a direction toward each other. The first encapsulant layer and the second encapsulant layer may be formed of a thermosetting resin or a thermoplastic resin. 
     The manufacturing method of the third embodiment may further include: removing the first film from the solar laminated assembly after the first operation. 
     The second operation may be varied according to a configuration of the first encapsulant layer and the second encapsulant layer disposed in the first operation. 
     For example, the first encapsulant layer may include a first layer adhered to a solar cell and formed of a thermosetting resin; and a second layer adhered to a first glass in the second operation and formed of a thermoplastic resin, and the second encapsulant layer may be formed of a thermosetting resin. Here, the second steep may include: additionally disposing a third encapsulant layer formed of a thermosetting resin between the second film and a back sheet or between the second film and a second glass; and performing a second lamination process of applying heat and pressure within a hermetically closed chamber. 
     In another example, both the first encapsulant layer and the second encapsulant layer may be formed of a thermosetting resin. Here, the second operation may include: additionally disposing an encapsulant layer which is the same as the first encapsulant layer between the first encapsulant layer and the first glass and additionally disposed a third encapsulant layer formed of a thermosetting resin between the second film and the back sheet or between the second film and the second glass; and performing a second lamination process of applying heat and pressure within a hermetically closed chamber. 
     Also, in another example, both the first encapsulant layer and the second encapsulant layer may be formed of a thermoplastic resin. Here, the second operation may include: additionally disposing a third encapsulant layer formed of a thermosetting resin between the second film and the back sheet or between the second film and the second glass; and performing a second lamination process of applying heat and pressure within a hermitically closed chamber. 
     In each embodiment, the second lamination process may include a preliminary adhering operation of partially melting 1) the third encapsulant layer in contact with the first glass and 2) the fourth encapsulant layer in contact with the back sheet or the second glass by introducing the solar laminated assembly to the inside of the hermitically closed chamber, vacuating the inside of the hermitically closed chamber, and substantially applying heat; and a main adhering operation of entirely melting 1) the third encapsulant layer in contact with the first glass and 2) the fourth encapsulant layer in contact with the back sheet or the second glass by applying heat and pressure to the solar laminated assembly within the hermetically closed chamber and subsequently curing the encapsulant layers. In both of the first lamination process and the second lamination process, the adhering operation may be used by applying both heat and pressure. 
     Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from the detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate example embodiments and together with the description serve to explain the principles of the invention. 
       In the drawings: 
         FIG. 1  is a conceptual view illustrating a photovoltaic module according to a first embodiment. 
         FIGS. 2A and 2B  are conceptual views illustrating a photovoltaic module according to a second embodiment. 
         FIGS. 3A and 3B  are conceptual views illustrating a photovoltaic module according to a third embodiment. 
         FIG. 4  is a common flow chart illustrating a method for manufacturing a photovoltaic module. 
         FIG. 5  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module according to a first embodiment. 
         FIGS. 6A and 6B  are conceptual views illustrating a process of manufacturing a photovoltaic module according to the flow charts illustrated in  FIGS. 4 and 5 . 
         FIG. 7  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module according to a second embodiment. 
         FIGS. 8A to 8C  are conceptual views illustrating a process of manufacturing a photovoltaic module according to the flow charts illustrated in  FIGS. 4 and 7 . 
         FIG. 9  is a detailed flow chart illustrating another method for manufacturing a photovoltaic module according to the second embodiment. 
         FIGS. 10A to 10C  are conceptual views illustrating a process of manufacturing a photovoltaic module according to the flow charts illustrated in  FIGS. 4 and 9 . 
         FIGS. 11A to 11C  are other conceptual views illustrating a process of manufacturing a photovoltaic module according to the flow charts illustrated in  FIGS. 4 and 9 . 
         FIG. 12  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module according to a third embodiment. 
         FIG. 13  is a detailed flow chart illustrating another method for manufacturing a photovoltaic module according to the third embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Description will now be given in detail of the example embodiments, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components will be provided with the same reference numbers, and description thereof will not be repeated. 
       FIG. 1  is a conceptual view of a photovoltaic module  100  according to a first embodiment. A multilayer structure of the photovoltaic module  100  is illustrated in  FIG. 1 . 
     The photovoltaic module  100  includes a solar laminated assembly  100   a , a first glass (a first substrate)  141  covering one side of the solar laminated assembly  100   a , and a back sheet or second glass (a second substrate)  142  covering the other side of the solar laminated assembly  100   a.    
     The solar laminated assembly  100   a  refers to a solar cell  110  and elements configured to protect the solar cells  110 , excluding a) the first glass  141  and b) the back sheet or second glass  142 , forming the outermost layers of the photovoltaic module  100 . In the present disclosure, the solar laminated assembly  100   a  refers to a half-finished product previously manufactured during a process of manufacturing the photovoltaic module  100 , and a concept of the solar laminated assembly  100   a  may differ depending on embodiments. 
     The solar laminated assembly  100   a  according to the first embodiment includes at least one solar cell  110 , films  121  and  122  disposed to cover opposing surfaces of the solar cell  110 , and encapsulant layers  131  and  132  adhering the films  121  and  122  to the solar cell  110 . 
     One or a plurality of solar cells  110  may be provided depending on a design of the photovoltaic module  100 . When the solar cell  110  is provided in a plurality, the plurality of solar cells may be disposed to be spaced apart from each other and may be connected in series to form a string. Also, the solar cells  110  may be disposed on the same curved surface. Referring to  FIG. 1 , the solar cells  110  are disposed between a curved surface of the first encapsulant layer  131  and a curved surface of the second encapsulant layer  132 . 
     Each solar cell  110  has a first surface  111  and a second surface  112  which face in mutually opposite directions. Light may be received (or collected) only to any one of the first surface  111  and the second surface  112  or to both of them. Here, first and second ordinal numbers are merely used for discriminating therebetween, without any specific technical meaning. 
     The films  121  and  122  are disposed to cover the solar cell  110 . The films  121  and  122  include a first film  121  and a second film  122  disposed to cover different surfaces. The first film  121  is disposed to cover the first surface  111  of the solar cell  110 , and the second film  122  is disposed to cover the second surface  112  of the solar cell  110 . 
     The first film  121  and the second film  122  form outermost surfaces of the solar laminated assembly  100   a  and are configured to protect opposing surfaces of the solar cell  110 . For example, a physical impact, moisture, and the like, may affect the solar cell  100 , and here, the first film  121  and the second film  122  may protect the solar cell  110  from a physical impact or moisture. 
     In particular, as described hereinafter, in the method for manufacturing the photovoltaic module  100 , after the solar laminated assembly  100   a  is first manufactured in a first operation (a first laminating operation), a) the first glass  141  and b) the back sheet or second glass  142  are adhered to the solar laminated assembly  100   a  in a second operation (a second laminating operation), and here, the films  121  and  122  serve to protect the solar cell  110  between the first operation and the second operation. 
     At least one of the films  121  and  122  may be formed of a transparent material. In order for the solar cell  110  to produce sufficient electric power, sufficient light has to be provided, and thus, the film covering a light receiving surface of the solar cell  110  is formed of a transparent material. For example, in instance where both the first surface  111  and the second surface  112  of the solar cell  110  receive light, both the first film  121  and the second film  122  are formed of a transparent material. In instance where only any one of the first surface  111  and the second surface  112  of the solar cell  110  receives light, only any one of the first film  121  and the second film  122  may be formed of a transparent material and the other may be formed of an opaque material. Even in instance where only any one of the first surface  111  and the second surface  112  of the solar cell  110  receives light, not all of the first film  121  and the second film  122  are required to be formed of a transparent material. However, when the photovoltaic module  100  is applied to an automobile roof or the interior/exterior material of a building, preferably, a film covering the opposite surface of the light receiving surface, among the first film  121  and the second film  122 , is formed of an opaque material in order to prevent an indoor area of the automobile or the building from being visually exposed through the photovoltaic module  100 . 
     When light is received by the first surface  111  of the solar cell  110 , the first film  121  may be formed of a transparent material, and here, the transparent material may be formed of polyethylene terephthalate (PET). In instance where the back sheet  142  of the photovoltaic module  100  is formed of a transparent material or in instance where the photovoltaic module  100  includes the second glass  142  (glass is always transparent), the second film  122  may be formed of a transparent material. The transparent material may be formed of PET, like the first film  121 . In instance where the back sheet  141  of the photovoltaic module  100  has a color such as black or white, the second film  122  may have a color to strengthen visibility. 
     The encapsulant layers  131  and  132  protect the solar cell  110 , and serve to adhere the films  121  and  122  to the solar cell  110 , respectively. The encapsulant layers  131  and  132  include a first encapsulant layer  131  and a second encapsulant layer  132 . The first encapsulant layer  131  is disposed between the first surface  111  and the first film  121  to adhere the first film  121  to the solar cell  110 . The second encapsulant layer  132  is disposed between the second surface  112  and the second film  122  to adhere the second film  122  to the solar cell  110 . 
     In the present disclosure, the encapsulant layers  131 ,  132 ,  133 , and  134  may be formed of a thermoplastic resin or a thermosetting resin. This may also be equally applied to the other embodiments, as well as to the first embodiment. 
     Thermoplasticity refers to properties deformed when heat is applied again after being formed by applying heat. In contrast, thermosetting properties refers to properties not deformed although heat is applied again, once deformed by applying heat. 
     In the present disclosure, types of a thermoplastic resin or thermosetting resin is not particularly limited. Any maternal may be used as a material of the encapsulant layer of the present disclosure as long as it is transparent, has adhesion when cured, and has thermoplasticity or thermosetting properties. For example, thermoplastic olefine (TPO), polyvinyl butyral (PVB), or polycarbonate (PC), which is transparent, has adhesion when cured, and has thermoplasticity, may be used as a material of the encapsulant layer of the present disclosure. Also, ethylene-vinyl acetate (EVA), which is transparent, has adhesion, and has thermosetting properties, may be used as a material of the encapsulant layer of the present disclosure. 
     In the photovoltaic module  100  of the first embodiment, the first encapsulant layer  131  and the second encapsulant layer  132  are preferably formed of a thermosetting resin. The photovoltaic module  100  of the first embodiment further includes a third encapsulant layer  133  and a fourth encapsulant layer  134  because arbitrary deformation of the first encapsulant layer  131  and the second encapsulant layer  132  is not desired in the process of thermosetting the third encapsulant layer  133  and the fourth encapsulant layer  134 . However, the first encapsulant layer  131  and the second encapsulant layer are not necessarily formed of a thermosetting resin and may be formed of any other material. 
     The first glass (first substrate)  141  is disposed to cover the first film  121 . The first glass  141  is adhered to the first film  121  by the third encapsulant layer  133  described hereinafter. The first glass  141  forms an outermost surface of one side of the photovoltaic module  100  and the first glass  141  may be referred to as a first outermost layer. 
     The first glass  141  has a curved surface. Here, however, the first glass  141  may not be entirely formed as a curved surface and only a partial region of the first glass  141  may be formed as a curved surface. 
     The back sheet or second glass (second substrate)  142  is disposed to cover the second film  122 . The back sheet or second glass  142  is adhered to the second film  122  by the fourth encapsulant layer  134  described hereinafter. The back sheet or second glass  142  is provided on the other outermost surface of the photovoltaic module  100  and may be referred to as a second outermost layer having a concept including the back sheet or second glass  142 . 
     In the photovoltaic module  100 , the back sheet or second glass  142  has a curved surface corresponding to the first glass  141 . The back sheet does not originally have a curved surface and as the back sheet is adhered to the solar laminated assembly  100   a , the back sheet forms a curved surface according to a curvature of the first glass. A curvature of the back sheet or second glass  142  may be substantially the same as that of the first glass  141  within an error range. Like the first glass  141 , a partial region of the back sheet or second glass  142  may also be formed as a curved surface. 
     The photovoltaic module  100  is not required to have both the back sheet and the second glass and may have only any one of the back sheet and the second glass  142 . For example, in instance where the photovoltaic module  100  is applied to an automobile roof, the photovoltaic module  100  may have a back sheet, and here, the first surface  111  of the solar cell  110  is a light receiving surface. 
     In instance where the photovoltaic module  100  has the second glass  142 , one side and the other side with respect to the solar cell  110  are symmetrical. Here, the first surface  111  and the second surface  112  of the solar cell  110  may not necessarily be distinguished. 
     The third encapsulant layer  133  is disposed between the first film  121  and the first glass  141  to adhere the first film  121  and the first glass  141 . Also, the fourth encapsulant layer  134  may be disposed between the second film  122  and the back sheet to adhere the second film  122  and the back sheet or disposed between the second film and the second glass  142  to adhere the second film  122  and the second glass  142 . Descriptions of the first encapsulant layer  133  and the second encapsulant layer  134  may also be applied to the third encapsulant layer  33  and the fourth encapsulant layer  134 . 
     Thicknesses of the third encapsulant layer  133  and the fourth encapsulant layer  134  may be greater than those of the first encapsulant layer  131  and the second encapsulant layer  132 . When the thickness of the encapsulant layer is greater, adhesion may be increased, and since the third encapsulant layer  133  and the fourth encapsulant layer  134  are used to adhere the glasses  141  and  142  heavier than the films  121  and  122 , the third encapsulant layer  133  and the fourth encapsulant layer  134  may be thicker than the first encapsulant layer  131  and the second encapsulant layer  132 . 
     As the first glass  141  has a curved surface and the second glass  142  has a curved surface, the solar cell  110 , the films  121  and  122 , and the encapsulant layers  131 ,  132 ,  133 , and  134  disposed therebetween also have a curved surface. This is because the first glass  141  has rigidity. Since a size of one solar cell  110  is smaller than the films  121  and  122  or the first glass  141 , although the solar cell  110  is bent, deformation of the solar cell  110  is smaller than that of the films  121  and  122  or the encapsulant layers  131 ,  132 ,  133 , and  134 . Also, the films  121  and  122  and the encapsulant layers  131 ,  132 ,  133 , and  134  are flexible to be bendable. 
     Thus, in the photovoltaic module  100  having the structure in which the first glass  141  and the back sheet or second glass  142  are adhered to the solar laminated assembly  100   a , a corner of the solar cell  110  is not broken. 
     Hereinafter, another embodiment of the present disclosure will be described. Here, the same description of another embodiment as that of the first embodiment will be omitted. 
       FIGS. 2A and 2B  are conceptual views illustrating photovoltaic modules  200  and  200 ′ according to a second embodiment. In  FIGS. 2A and 2B , multilayer structures of the two photovoltaic modules  200  and  200 ′ are illustrated, respectively. 
     The photovoltaic modules  200  and  200 ′ of the second embodiment are distinguished from the first embodiment in that they do not include the films  121  and  122  (please refer to  FIG. 1 ) and do not include the third encapsulant layer  133  (please refer to  FIG. 1 ) and the fourth encapsulant layer  134  (please refer to  FIG. 1 ). 
     In the photovoltaic modules  200  and  200 ′ of the second embodiment, a first encapsulant layer  231  is disposed between a solar cell  210  and a first glass (a first substrate)  241  and adhered to the solar cell  210  and the first glass  241 . A second encapsulant layer  232  is disposed between the solar cell  210  and a back sheet or between the solar cell  210  and a second glass (a second substrate)  242  and adhered to the solar cell  210  and the back sheet or adhered to the solar cell  210  and the second glass  242 . 
     The second embodiment may be classified as embodiment 2-1 and embodiment 2-2. The photovoltaic module  200  of the embodiment 2-1 has a first encapsulant layer and a second encapsulant layer each including two layers, whereas the photovoltaic module  200 ′ of the embodiment 2-2 has a first encapsulant layer and a second encapsulant layer each including one layer. 
     In the photovoltaic module  200  of the embodiment 2-1 illustrated in  FIG. 2A , the first encapsulant layer  231  and the second encapsulant layer  232  each include two layers. In order to distinguish between the two layers of the first encapsulant layer  231  and in order to distinguish between the two layers of the second encapsulant layer  232 , layers of the first and second encapsulant layers  231  and  232  which are adhered to the solar cell  210  will be termed first layers  231   a  and  232   a  and layers thereof which are adhered to the first glass  241  or the back sheet or second glass  242  will be termed second layers  231   b  and  232   b.    
     Any one of the first layer  231   a  or  232   a  and the second layer  231   b  or  232   b  may be formed of a thermosetting resin, and the other may be formed of a thermoplastic resin. For example, the first layers  231   a  and  232   a  may be formed of a thermosetting resin, and the second layers  231   b  and  232   b  may be formed of a thermoplastic resin. 
     Conversely, the first layers  231   a  and  232   a  may be formed of a thermoplastic resin, and the second layers  231   b  and  232   b  may be formed of a thermosetting resin. Here, the second layers  231   b  and  232   b  serve to strengthen adhesion. 
     In another example, both the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  may be formed of a thermosetting resin. Here, the second layers  231   b  and  232   b  may be thicker than the first layers  231   a  and  232   a . When both the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  are formed of the same thermosetting resin, the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  may not be visually distinguishable but are formed to be thicker than a thickness of an encapsulant layer including one layer. For example, in the first embodiment, when a thickness of the first encapsulant layer  131  to the fourth encapsulant layer  134  (please refer to  FIG. 1 ) is about 450-550 μm, the first encapsulant layer  231  and the second encapsulant layer  232  may be greater than 450 μm but smaller than 1100 μm. 
     In the photovoltaic module  200 ′ of the embodiment 2-2 illustrated in  FIG. 2A , the first encapsulant layer  231  and the second encapsulant layer  232  are formed of a thermoplastic resin of one layer. Since the first encapsulant layer  231  and the second encapsulant layer  232  have thermoplasticity so that the first encapsulant layer  231  and the second encapsulant layer  232  are melted and then cured in each process of performing heat treatment during a manufacturing process of the photovoltaic module  200 ′ to thus adhere components of the photovoltaic module  200 ′. 
       FIGS. 3A and 3B  are conceptual views illustrating photovoltaic modules  300  and  300 ′ of a third embodiment. In  FIGS. 3A and 3B , multilayer structures of the photovoltaic modules  300  and  300 ′ are illustrated, respectively. 
     The photovoltaic modules  300  and  300 ′ of the third embodiment are distinguished from the first and second embodiments described above, in that the photovoltaic modules  300  and  300 ′ include a second film  322 , rather than a first film. In the following descriptions, the second film  322  will be referred to as a film  322 . 
     In the photovoltaic modules  300  and  300 ′ of the third embodiment, a first encapsulant layer  331  is disposed between a solar cell  310  and a first glass (a first substrate)  341  and adhered to the solar cell  310  and the first glass  341 . The second encapsulant layer  332  is disposed between the solar cell  310  and the film  322  and adhered to the solar cell  310  and the film  322 . A third encapsulant layer  333  is disposed between the film  322  and a back sheet or between the film  322  and a second glass (a second substrate)  342  and adhered to the film  322  and the back sheet or adhered to the film  322  and the second glass  342 . 
     The third embodiment may be classified as embodiment 3-1 and embodiment 3-2. The photovoltaic module  300  of the embodiment 3-1 has the first encapsulant layer  331  including two layer, whereas the photovoltaic module  300 ′ of the embodiment 3-2 has the first encapsulant layer  331  including one layer. 
     In the photovoltaic module  300  of the embodiment 3-1 illustrated in  FIG. 3A , the first encapsulant layer  331  includes two layers. A first layer  331   a  may be formed of a thermosetting resin, and a second layer  331   b  may be formed of a thermoplastic layer. Also, the second encapsulant layer  332  and the third encapsulant layer  333  may be formed of a thermoplastic resin. 
     In another example, both the first layer  331   a  and the second layer  331   b  of the first encapsulant layer  331  may be formed of a thermosetting resin, and the second encapsulant layer  332  and the third encapsulant layer  333  may be formed of a thermoplastic resin. Here, the second layer  331   b  may be thicker than the first layer  331   a , and the third encapsulant layer  333  may be thicker than the second encapsulant layer  332 . This is because the second layer and the third encapsulant layer are adhered to a first glass or a second glass requiring strong adhesion. 
     In the photovoltaic module  300 ′ of the embodiment 3-2 illustrated in  FIG. 3B , the first encapsulant layer  331  is formed of a thermoplastic resin of one layer. The second encapsulant layer  332  may also be formed of a thermoplastic resin, and the third encapsulant layer  333  may be formed of a thermosetting resin. In the photovoltaic modules  300  and  300 ′ having such a structure, a corner of the solar cell  310  is not broken. 
       FIG. 4  is a common flow chart illustrating a method for manufacturing photovoltaic modules  100 ,  200 ,  200 ′,  300 , or  300 ′ 
     The photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ of the present disclosure is manufactured by a first operation S 100  and a second operation S 200 . Also, operation S 150  of removing first and/or second film may be provided between the first operation S 100  and the second operation S 200 , but the operation S 150  of removing the first and/or second film is not essential and is optional. That is, the operation S 150  may be omitted according to an embodiment. 
     In the first operation S 100 , a solar laminated assembly is manufactured. The solar laminated assembly refers to a half-finished product previously manufactured during a manufacturing process of the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ and a specific concept thereof may be varied according to embodiments. 
     In order to manufacture the solar laminated assembly, first, a first encapsulant layer and a first film are sequentially stacked on a first surface of a solar cell, and a second encapsulant layer and a second film are sequentially stacked on a second surface of the solar cell (S 110 ). In the present disclosure, the encapsulant layers may be formed of a thermoplastic resin or a thermosetting resin as mentioned above. Also, at least one of the first film and the second film may be formed of a transparent material as mentioned above. 
     Here, sequentially stacking refers to a structure in which the first encapsulant layer is stacked on the first surface of the solar cell and the first film is stacked on the first encapsulant layer, rather than order of stacking. For example, it does not exclude stacking the first encapsulant layer and the first film temporally simultaneously on the first surface of the solar cell in a state in which the first film is already stacked on the first encapsulant layer. This descriptions may also be equally applied to the second encapsulant layer and the second film. 
     Thereafter, through a first lamination process, the first film is adhered to the first surface of the solar cell and the second film is adhered to the second surface of the solar cell (S 120 ). Lamination refers to a process of thermosetting the encapsulant layers formed of a thermosetting resin or a thermoplastic resin by applying heat and pressure to thus adhere two adhering targets disposed on one side and the other side of the encapsulant layer. A specific process of lamination may be different in first and second lamination processes. 
     In the first lamination process, two adhering targets are a solar cell and films. The first lamination process is performed on a plane. When heat is applied to the first encapsulant layer and the second encapsulant layer, while pressing the first film and the second film in a direction toward each other, the first encapsulant layer and the second encapsulant layer are melted and cured and the first film and the second film are adhered to the first surface and the second surface of the solar cell, respectively. 
     Pressure applied during the first lamination process is surface pressure. Here, surface pressure refers to pressure equally applied to the entirety of the flat first film and the flat second film, which is to be distinguished from pressure applied only to any partial region. 
     When the first lamination process is completed, a solar laminated assembly is manufactured. A concept of the solar laminated assembly has been described above with reference to  FIG. 1  and may be varied according to embodiments. Since the solar laminated assembly is manufactured by the first lamination process of applying surface pressure, the solar laminated assembly has a planar structure. The first and second encapsulant layers and the first and second films are flexible, and the solar cells are spaced apart from each other. Thus, the solar laminated assembly may be bent to be concave or convex by an external force applied in the second operation S 200 . 
     After the solar laminated assembly is manufactured in the first operation S 100 , the second operation S 200  may be immediately performed or operation S 150  of removing the first and/or second films may be performed beforehand. 
     Since there is a temporal interval between the first operation S 100  and the second operation S 200 , the solar laminated assembly manufactured in the first operation S 100  is required to be protected from an external influence. The external influence may refer to an influence which may be made on performance of the solar cell such as a physical impact, moisture, or the like. Since the first film and the second film form outermost layers of the solar laminated assembly, the first and second films protect the solar laminated assembly. 
     When the second operation S 200  starts, since the first film and the second film has completed a role of protecting the solar laminated assembly, at least one of the first film and the second film may be removed immediately before the second operation S 200  starts. For example, in instance where the first film and the second film are configured as release films, the first film and the second film may be separated and removed from the first encapsulant layer and the second encapsulant layer, respectively. 
     However, operation S 150  of removing the first film and/or the second film is not essential. When the first film and the second film are not removed, the first film and the second film remain on the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′, a finished product. Thus, at least one of the first film and the second film remaining in the photovoltaic module  100 ,  200 ,  200 ′,  300 , and  300 ′ is required to be formed of a transparent material in order to sufficiently supply light to the solar cell. 
     In a state in which the first film and the second film are present, outermost layers of the solar laminated assembly are formed by the first film and the second film. When the first film and the second film are removed, the first encapsulant layer and the second encapsulant layer are exposed. 
     In the second operation S 200 , an encapsulant layer may be additionally selectively disposed before the second lamination process S 220 . However, whether to additionally disposed an encapsulant layer differs according to embodiments, and thus, details thereof will be described in each embodiment. 
     Thereafter, in the second operation S 200 , a first glass is adhered to the first surface of the solar laminated assembly and a back sheet or second glass is adhered to the second surface thereof through the second lamination process S 220 . The first glass is formed to have a curved surface. The back sheet, which is originally flat, may be bent to have a curvature corresponding to the first glass as it is adhered to the second surface of the solar laminated assembly. In contrast, the second glass is different from the back sheet in that the second glass is originally formed to have a curved surface corresponding to the first glass. 
     As the first glass and the second glass are formed to have a curved surface, the second lamination process may be performed on a plane. Thus, the second lamination process is performed in a manner different from that of the first lamination process. 
     The second lamination process includes a preliminary adhering operation S 221  and a regular adhering operation S 222 . 
     In the preliminary adhering operation S 221 , the solar laminated assembly is introduced to the inside of a hermetically closed chamber, the inside of the chamber is vacuated and heat is applied to partially melt the encapsulant layer. Thereafter, in the regular adhering operation S 222 , when heat and pressure are applied, the encapsulant layers are entirely melted and then cured within the hermetically closed chamber, In this instance, the thermoplastic resin which was melted and then cured during the first lamination process is not melted again during the second lamination process. 
     In the photovoltaic module  100  of the first embodiment, a component for adhering the first glass  141  to the solar laminated assembly  100   a  is the third encapsulant layer  133 , and a component for adhering the back sheet or second glass  142  to the solar laminated assembly  100   a  is the fourth encapsulant layer. Thus, the third encapsulant layer  133  and the fourth encapsulant layer  134  are partially melted in the preliminary adhering operation S 221  of the second lamination process and entirely melted and then cured in the regular adhering operation S 222 . 
     In contrast, in the photovoltaic module  200  or  200 ′ of the second embodiment, a component for adhering the first glass to the solar laminated assembly is the first encapsulant layer  231  and a component for adhering the back sheet or second glass  242  to the solar laminated assembly is the second encapsulant layer  232 . Thus, the first encapsulant layer  231  and the second encapsulant layer  232  are partially melted in the preliminary adhering operation S 221  of the second lamination process and entirely melted and then cured in the regular adhering operation S 222 . 
     Also, in the photovoltaic module  300  or  300 ′ of the third embodiment, a component for adhering the first glass to the solar laminated assembly is the first encapsulant layer  331  and a component for adhering the back sheet or second glass  342  to the solar laminated assembly is the third encapsulant layer  333 . Thus, the first encapsulant layer  331  and the third encapsulant layer  333  are partially melted in the preliminary adhering operation S 221  of the second lamination process and entirely melted and then cured in the regular adhering operation S 222 . 
     When the solar laminated assembly is adhered to the first glass  141 ,  241 , or  341  having a curved surface and the back sheet or the second glass  142 ,  242 , or  342  having a curved surface is adhered to the solar laminated assembly through the second lamination process S 220  including the preliminary adhering operation S 221  and the regular adhering operation S 222 , the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ is manufactured. The photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ manufactured thusly has an overall bent shape, and a curvature of the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ is determined by a curvature of the first glass  141 ,  241 , or  341  and a curvature of the second glass  142 ,  242 , or  342 . 
     When the solar cell is directly adhered to the glass having the curved glass only through the first lamination process, the solar cell may be broken. In the present disclosure, however, the solar laminated assembly is previously manufactured through the first lamination process S 120  performed on a plane, and thereafter, the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ is manufactured through the second lamination process S 220 . Thus, although the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′ in a bent form is manufactured, the solar cell is not broken. 
     Also, when the solar cell is directly adhered to the glass having a curved surface only through the first lamination process, the string connecting the solar cells may slide down the curved surface of the glass to cause a possibility that the photovoltaic module is manufactured to be different from the original design. However, in the present disclosure, since the solar laminated assembly is previously manufactured through the first lamination process S 120  performed on the plane, although the solar laminated assembly is adhered to the first glass  141 ,  241 , or  341  having a curved surface through the second lamination process S 220 , the problem in which the solar cells slide down does not arise. 
     In addition, if both of the two outermost layers of the photovoltaic module are formed of glass, bubbles may be generated within the photovoltaic module due to an operation between the solar cell and a ribbon structure. However, in the present disclosure, since the solar laminated assembly is previously manufactured through the first lamination process S 120 , although the first glass  141 ,  241 , or  341  having a curved surface and the second glass  142 ,  242 , or  342  having a curved surface form the outermost layers of the photovoltaic module  100 ,  200 ,  200 ′,  300 , or  300 ′, bubbles may not be generated. 
     Hereinafter, a detailed process of manufacturing the photovoltaic modules  100 ,  200 ,  200 ′,  300 , and  300 ′ of the first to third embodiments will be described. Descriptions of a common method thereof will be replaced with the descriptions of  FIG. 4  and only different components of each embodiment will be described. 
       FIG. 5  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module according to a first embodiment.  FIGS. 6A and 6B  are conceptual views illustrating a process of manufacturing the photovoltaic module  100  according to the flow charts illustrated in  FIGS. 4 and 5 . 
     In  FIG. 6A , the first lamination process of the first operation S 100  is illustrated. The first film  121  is adhered to the first surface  111  of the solar cell  110  as the first encapsulant layer  131  is thermally cured, and the second film  122  is adhered to the second surface  112  of the solar cell  110  as the second encapsulant layer  132  is thermally cured. 
     Since the photovoltaic module  100  of the first embodiment are required to include the first film  121  and the second film  122 , the first film  121  and the second film  122  are not removed after operation S 100 . 
     In the photovoltaic module  100  of the first embodiment, the first to fourth encapsulant layers  131 ,  132 ,  133 , and  134  may be formed of a thermosetting resin or a thermoplastic resin. 
     Once the thermosetting resin is thermally cured, the thermosetting resin is not deformed although heat is applied again thereto. Thus, the first encapsulant layer  131  and the second encapsulant layer  132  cured through the first lamination process in the first operation S 100  are not deformed although heat is applied through the second lamination process S 220  described hereinafter. Meanwhile, although the thermoplastic resin is thermally cured through the first lamination process, when heat is applied again through the second lamination process S 220 , the thermoplastic resin is melted and thermally cured. 
     Referring to  FIG. 5 , in the second operation S 200 , the third encapsulant layer  133  is disposed between the first film  121  and the first glass  141  and the fourth encapsulant layer  134  is disposed between the second film  122  and the back sheet or between the second film  122  and the second glass  142 . Accordingly, a structure in which the first encapsulant layer  131 , the first film  121 , the third encapsulant layer  133 , and the first glass  141  are sequentially stacked is formed on the first surface  111  of the solar cell  110 . Also, a structure in which the second encapsulant layer  132 , the second film  122 , the fourth encapsulant layer  134 , and the back sheet or the second glass  142  are sequentially stacked is formed on the second surface  112  of the solar cell  110 . 
     Thereafter, the first glass  141  is adhered to the first film  121  through the second lamination process S 220 , and the back sheet or second glass  142  is adhered to the second film  122 . Details of the second lamination process has been described above with reference to  FIG. 4 . As the third encapsulant layer  133  is thermally cured, the first glass  141  is adhered to the first surface of the solar laminated assembly  100   a , and as the fourth encapsulant layer  134  is thermally cured, the back sheet or second glass  142  is adhered to the second surface of the solar laminated assembly  100   a . In this embodiment, the first surface of the solar laminated assembly  100   a  refers to the first film  121 , and the second surface thereof refers to the second film  122 . 
       FIG. 6B  illustrates that the first glass  141  is adhered to the first film  121  and the back sheet or second glass  142  is adhered to the second film  122  through the second lamination process S 220 . 
     Since the first glass  141  is formed to have a curved surface, when the solar laminated assembly  100   a  is adhered to the first glass  141 , the solar laminated assembly  100   a  is naturally bent to have the same curvature as that of the first glass  141 . Similarly, when the back sheet is adhered to the solar laminated assembly  100   a , the back sheet is bent to have the same curvature as that of the first glass  141 . 
       FIG. 7  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module according to a second embodiment.  FIGS. 8A to 8C  are conceptual views illustrating a process of manufacturing a photovoltaic module  200  according to the flow charts illustrated in  FIGS. 4 and 7 . 
     In  FIG. 8A , the first lamination process S 120  of the first operation S 100  is illustrated. As the first layer  231   a  of the first encapsulant layer  231  is thermally cured, the first film  221  is adhered to the first surface  211  of the solar cell  210 , and as the first layer  232   a  of the second encapsulant layer  232  is thermally cured, the second film  222  is adhered to the second surface  212  of the solar cell  210 . 
     The first film  221  and the second film  222  are formed as release films, and the photovoltaic module  200  of the second embodiment does not include the first film  221  and the second film  222 . Thus, after the first operation S 110 , the first film  221  and the second film  222  are removed (S 150 ). Also, in  FIG. 8B , the solar laminated assembly  200   a  after removing the first film  221  and the second film  222  is illustrated. 
     Referring to  FIG. 7 , in the second operation S 200 , a second layer  231   b  of the first encapsulant layer  231  is additionally disposed between the first film  221  and the first glass  241  and the second layer  232   b  of the second encapsulant layer  232  is additionally disposed between the second film  222  and the back sheet or between the second film  222  and the second glass  242  (S 211 ). 
     In the photovoltaic module  200  of the second embodiment, the first encapsulant layers  231   a  and  231   b  and the second encapsulant layers  232   a  and  232   b  may each include two layers, and, among the two layers, the first layers  231   a  and  232   a  are adhered to the solar cell  21  in a first operation. Also, the second layers  231   b  and  232   b  are adhered to the first glass  241   a  and the back sheet or second glass  242  in a second operation. The first layers  231   a  and  232   a  may be formed of a thermosetting resin or a thermoplastic resin, and the second layers  231   b  and  232   b  may be formed of a thermosetting resin. 
     When the first layers  231   a  and  232   a  are formed of a thermoplastic resin and the second layers  231   b  and  232   b  are formed of a thermosetting resin, the second layers  231   b  and  232   b  are added in the second operation to enhance adhesion. 
     When both the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  are formed of a thermosetting resin, a thickness of the second layers  231   b  and  232   b  may be greater than that of the first layers  231   a  and  232   a . This is because the second layers  231   b  and  232   b  are adhered to the first glass  2421  and the back sheet or second glass  242  requiring strong adhesion. When both the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  are formed of a thermosetting resin, the first layers  231   a  and  232   a  and the second layers  231   b  and  232   b  have a thickness greater than that of a thermosetting resin of a single layer, as described above. 
     As the second layer  231   b  of the first encapsulant layer and the second layer  231   b  of the second encapsulant layer are additionally disposed, a structure in which the first layer  231   a  and the second layer  231   b  of the first encapsulant layer  231  and the first glass  241  are sequentially stacked is formed on the first surface  211  of the solar cell  210 . Also, a structure in which the first layer  232   a  and the second layer  232   b  of the second encapsulant layer  232  and the back sheet or second glass  242  are sequentially stacked is formed on the second surface  212  of the solar cell  210 . 
     Thereafter, the first glass  241  and the back sheet or second glass  242  are adhered to the solar laminated assembly  200   a  through the second lamination process S 220 . Details of the second lamination process has been described above with reference to  FIG. 4 . 
     As the second layer  231   b  of the first encapsulant layer  231  is thermally cured, the first glass  241  is adhered to the first surface of the solar laminated assembly  200   a , and as the second layer  232   b  of the second encapsulant layer  232  is thermally cured, the back sheet or second glass  242  is adhered to the second surface of the solar laminated assembly  200   a . Since the first film and the second film have already been removed, here, the first surface of the solar laminated assembly  200   a  refers to the first layer  231   a  of the first encapsulant layer  231  and the second surface refers to the first layer  232   a  of the second encapsulant layer  232 . 
       FIG. 8C  illustrates that the first glass  241  is adhered to the first layer  231   a  and the back sheet or second glass  242  is adhered to the first layer  232   a  of the second encapsulant layer  232  through the second lamination process S 220 . 
       FIG. 9  is a detailed flow chart illustrating another method for manufacturing a photovoltaic module  200  or  200 ′ according to the second embodiment.  FIGS. 10A to 10C  are conceptual views illustrating a process of manufacturing the photovoltaic module  200  according to the flow charts illustrated in  FIGS. 4 and 9 .  FIGS. 11A to 11C  are other conceptual views illustrating a process of manufacturing the photovoltaic module  200 ′ according to the flow charts illustrated in  FIGS. 4 and 9 . 
     This embodiment is distinguished from the embodiment described above with reference to  FIG. 7 , in that an encapsulant layer is not added in a second operation. A first encapsulant layer and a second encapsulant layer may each include two layers or one layer. In either instance, the first encapsulant layer and the second encapsulant layer are added only in the first operation to configure the solar laminated assembly, and are not added in the second operation. 
     In  FIG. 9 , the first encapsulant layer and the second encapsulant layer each including two layers are added in operation S 112 , and a corresponding manufacturing process is illustrated in  FIGS. 10A to 10C . Also, the first encapsulant layer and the second encapsulant layer each including a single layer are added in operation S 113 , and a corresponding manufacturing process is illustrated in  FIGS. 11A to 11C . 
     In  FIG. 10A , the first lamination process (S 120 ) of the first operation S 100  is illustrated. As the first encapsulant layer  231  is thermally cured, the first film  221  is adhered to the first surface  211  of the solar cell  210 , and as the second encapsulant layer  232  is thermally cured, the second film  222  is adhered to the second surface  212  of the solar cell  210 . 
     In this embodiment, the first layers  231   a  and  232   a  are formed of a thermosetting resin, and the second layers  231   b  and  232   b  are formed of a thermoplastic resin. In the first lamination process, both the first layer  231   a  and the second layer  231   b  of the first encapsulant layer  231  are thermally cured, and both the first layer  231   a  and the second layer  231   b  of the second encapsulant layer  232  are thermally cured. However, since the second layer  231   b  of the first encapsulant layer  231  and the second layer  232   b  of the second encapsulant layer  232  are formed of a thermoplastic resin, when the second layer  231   b  of the first encapsulant layer  231  and the second layer  232   b  of the second encapsulant layer  232  are re-heated in the second lamination process, they are deformed again. 
     The first film  221  and the second film  222  are formed as release films, and the photovoltaic module  200  of the second embodiment do not include the first film  221  and the second film  222 . Thus, after the first operation S 100 , the first film  221  and the second film  222  are removed (S 150 ). The second layer  231   b  of the first encapsulant layer  231  and the second layer  232   b  of the second encapsulant layer  232  are exposed. In  FIG. 10B , the solar laminated assembly  200   a  after the first film  221  and the second film  222  were removed is illustrated. 
     In the photovoltaic module  200  of this embodiment, since the second layer  231   b  of the first encapsulant layer  231  and the second layer  232   b  of the second encapsulant layer  232  are formed of a thermoplastic resin, although the second layer  231   b  of the first encapsulant layer  231  and the second layer  232   b  of the second encapsulant layer  232  are thermally cured by first lamination process, they are deformed when heat is applied thereto again. Thus, an additional encapsulant layer for adhering the first glass  241  or the back sheet or second glass  242  is not required. 
     In the second operation S 200 , through the second lamination process S 220 , the first glass  241  is adhered to the first film  221  and the back sheet or second glass  242  is adhered to the second film  222  without adding an encapsulant layer. Details of the second lamination are the same as that described above with reference to  FIG. 4 . As the second layer  231   b  of the first encapsulant layer  231  is thermally cured, the first glass  241  is adhered to the first surface of the solar laminated assembly  200   a , and as the second layer  232   b  of the second encapsulant layer  232  is thermally cured, the back sheet or second glass  242  is adhered to the second glass of the solar laminated assembly  200   a.    
     In  FIG. 10C , a process of adhering the first glass  241  to the second layer  231   b  of the first encapsulant layer  231  and adhering the back sheet or second glass  242  to the second layer  232   b  of the second encapsulant layer  232  through the second lamination process is illustrated. 
     In  FIG. 11A , the first lamination process S 120  of the first operation S 100  is illustrated. As the first encapsulant layer  231  is thermally cured, the first film  221  is adhered to the first surface  211  of the solar cell  210 , and as the second encapsulant layer  232  is thermally cured, the second film  222  is adhered to the second surface  212  of the solar cell  210  as the second encapsulant layer  232  is thermally cured. 
     The first film  221  and the second film  222  are formed as release films, and the photovoltaic module  200 ′ of the second embodiment does not include the first film  221  and the second film  222 . Thus, after the first operation S 100 , the first film  221  and the second film  222  are removed (S 150 ). In  FIG. 11B , the solar laminated assembly  200   a ′ after removing the first film  221  and the second film  222  is illustrated. 
     In the photovoltaic module  200 ′ of this embodiment, the first encapsulant layer  231  and the second encapsulant layer  232  are formed of a thermoplastic resin of a single layer. Although the thermoplastic resin is thermally cured by the first lamination process, when heat is applied thereto, the thermoplastic resin is deformed again. Thus, an additional encapsulant layer for adhering the first glass  241  or the back sheet or second glass  242  is not required. 
     In the second operation S 200 , without adding a separate encapsulant layer, the first glass  241  is adhered to the first surface of the solar laminated assembly  200   a  and the back sheet or second glass  242  is adhered to the second surface thereof through the second lamination process S 220 . Details of the second lamination process is the same as described above with reference to  FIG. 4 . As the first encapsulant layer  231  is thermally cured again, the first glass  241  is adhered to the first surface of the solar laminated assembly  200   a , and as the second encapsulant layer  232  is thermally cured, the back sheet or second glass  242  is adhered to the second surface of the solar laminated assembly  200   a . The first encapsulant layer  231  and the second encapsulant layer  232  are heat-treated twice in the first operation S 100  and the second operation S 200 . 
     In  FIG. 11C , a process of adhering the first glass  241  to the first encapsulant layer and adhering the back sheet or second glass  242  to the second encapsulant layer  232  through the second lamination process is illustrated. 
       FIG. 12  is a detailed flow chart illustrating a method for manufacturing a photovoltaic module  300  according to a third embodiment. Reference numerals will be referred to  FIG. 3A . 
     In the first operation S 100 , first, the first layer  331   a  of the first encapsulant layer  331  is disposed on a first surface  311  of the solar cell  310  and the second encapsulant layer  332  formed of a single layer is disposed on a second surface  312  of the solar cell  310 . Also, a first film (not shown) is adhered to the first surface  311  and a second film  322  is adhered to the second surface  312  of the solar cell  310 . Accordingly, the solar laminated assembly is formed. 
     The first layer  331   a  of the first encapsulant layer  331  and the second encapsulant layer  332  may be formed of a thermosetting resin. 
     The photovoltaic module  300  of the third embodiment does not include the first film, and the first film is removed between the first operation and the second operation (S 150 ′). In the solar laminated assembly, the first film is removed and the first layer  331   a  of the first encapsulant layer  331  is exposed. 
     Thereafter, in the second operation S 200 , the second layer  331   b  of the first encapsulant layer  331  is additionally disposed between the first layer  331   a  of the first encapsulant layer  331  and the first glass  341  and the third encapsulant layer  333  is additionally disposed between the second film  322  and the back sheet or between the second film  322  and the second glass  342  (S 212 ). The second layer  331   b  and the third encapsulant layer  333  may be formed of a thermosetting resin. Also, in order to ensure strong adhesion, the second layer  331   b  of the first encapsulant layer  331  may be thicker than the first layer  331   a  and the third encapsulant layer  333  may be thicker than the second encapsulant layer  332 . 
     Finally, through the second lamination process S 220 , the first glass  341  is adhered to the first surface of the solar laminated assembly and the back sheet or second glass  342  is adhered to the second surface of the solar laminated assembly. 
       FIG. 13  is a detailed flow chart illustrating another method for manufacturing a photovoltaic module  300  or  300 ′ according to the third embodiment. The method described in  FIG. 13 , operation S 115  and operation S 116  are distinguished from each other. The photovoltaic module  300  or  300 ′ of the third embodiment does not include a first film and includes the second film  322 , and thus, the first film is removed (S 150 ′) between the first operation S 100  and the second operation S 200  as described above. 
     First, referring to operation S 115 , the first encapsulant layer  331  includes the first layer  331   a  and the second layer  331   b , both the two layers  331   a  and  331   b  are disposed on the first surface  311  of the solar cell  310  in the first operation S 100 . Also, the second encapsulant layer  332  formed as a single layer is disposed on the second surface  312  of the solar cell  310 . The embodiment of  FIG. 13  is distinguished from the embodiment of  FIG. 12 , in that the two layers  331   a  and  331   b  of the first encapsulant layer  331  are disposed on the first surface  311  of the solar cell  310  in the first operation S 100  and only the third encapsulant layer  333  is added (S 213 ) in the second operation S 200 . 
     The first layer  331   a  of the first encapsulant layer  331  is formed of a thermosetting resin, and the second layer  331   b  may be formed of a thermoplastic resin. Also, both the second encapsulant layer  332  and the third encapsulant layer  333  may be formed of a thermosetting resin. Through this embodiment, the photovoltaic module  300  illustrated in  FIG. 3A  is manufactured, and the other descriptions thereof may be replaced with the above descriptions. 
     Referring to operation S 116 , both the first encapsulant layer  331  and the second encapsulant layer  332  are formed as a single layer, and the first encapsulant layer  331  is disposed on the first surface  311  of the solar cell  310  in the first operation S 100 , and the second encapsulant layer  332  is disposed on the second surface  312  of the solar cell  310 . Both the first encapsulant layer  331  and the second encapsulant layer  332  are formed of a thermoplastic resin. Meanwhile, the third encapsulant layer  333  is formed of a thermosetting resin. 
     Only the third encapsulant layer  333  is added (S 213 ) in the second operation S 200 , and through this embodiment, the photovoltaic module  300 ′ illustrated in  FIG. 3B  is manufactured. The other descriptions thereof may be replaced with the above descriptions. 
     The photovoltaic module and the manufacturing method thereof described above are not limited to the components and methods of the embodiments described above and the entirety or a portion of the embodiments may be selectively combined to various modifications. 
     According to the present disclosure having the configuration described above, although the outermost layer of the photovoltaic module is formed of glass with a curved surface, since the solar cell is protected by the first lamination process and thus stress applied to the solar cell due to the curved surface is alleviated, the solar cell is not broken. Thus, the photovoltaic module may be applied to a roof of an automobile, an interior or exterior material of a building, and the like, requiring a curved surface functionally or in design. 
     Also, in the present disclosure, since the solar laminated assembly is previously manufactured through the first lamination process in the first operation and the solar laminated assembly is post-bonded to the curved glass, 1) the problem of generation of bubbles and 2) the problem that an array of strings connecting solar cells slide down the curved surface to break the array of the solar cells do not arise. Thus, when the present disclosure is used, the curved photovoltaic module as initially designed may be manufactured. 
     The foregoing embodiments and advantages are merely example and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the example embodiments described herein may be combined in various ways to obtain additional and/or alternative example embodiments. 
     As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.