KR20100131201A - Photo voltaic module with heat radiating eva layer - Google Patents

Abstract

PURPOSE: A photovoltaic module including an ethylene vinyl acetate layer with a superior heat emitting characteristic is provided to maximize generating efficiency by reducing heat in the module and peripheral units in order to reduce temperature in the module. CONSTITUTION: Back side solar ethylene vinyl acetate(40') is formed on a back sheet based on a fluorine resin. The back side solar ethylene vinyl acetate contains heat emitting material powder. A solar cell(30) is formed on the back side solar ethylene vinyl acetate. Front solar ethylene vinyl acetate(20) is formed on the solar cell. A glass substrate(10) is formed on the front solar ethylene vinyl acetate.

Description

Photovoltaic module with EVA layer having heat dissipation property {Photo Voltaic module with heat radiating EVA layer}

The present invention relates to a photovoltaic module having a structure in which a back sheet is removed from a conventional photovoltaic module, having a heat dissipation function by adding a thermally conductive metal powder to the rear surface EVA. Solar solar power generation module having an EVA layer having heat dissipation characteristics by maximizing the amount of solar power generated by cooling the module for photovoltaic generation and its peripheral devices by the heat dissipation effect of the back solar EVA It is about a module.

In general, photovoltaic power generation is known to have a relatively high power generation efficiency in a high amount of sunshine, and the current solar power generation business area is also being closely connected to the amount of sunshine.

According to the above theory, the conventional photovoltaic power plant should have high solar power generation in a season when the sunshine peaks, but in reality, as shown in FIG. 1, the sunshine is less than in June when the sunshine peaks. The average solar power generation in April and November is cool, and the average solar power generation is maintained when the surface temperature of the photovoltaic module maintains a high temperature of approximately 60 to 80 ° C in August, when the atmospheric temperature is the highest. Efficiency drops to 12%. That is, as is generally known, the amount or efficiency of generation according to the surface temperature of the photovoltaic module is not significantly affected by the single crystal polysilicon or the polycrystalline silicon photovoltaic module, and the photovoltaic module itself and It can be seen that the heat of the peripheral device has a great effect on the amount of solar power generation.

This fact clearly shows a difference in power generation efficiency of approximately 5 to 10% as shown in seasonal photovoltaic power generation, as shown in FIG. 1. It is shown in the general literature that the difference in generation amount is approximately 5% or more. In other words, under the same sunshine conditions, as the temperature changes in the module and surroundings, the lower the temperature, the greater the amount of power generation. In general, photovoltaic power generation is generally the most efficient in the summer with the highest amount of sunshine. This phenomenon is the same in not only polycrystalline or monocrystalline crystalline silicon solar cells but also thin film solar cells.

As described above, the amount of photovoltaic power generation is greatly influenced by the temperature change of the photovoltaic module and its peripheral device, but a typical photovoltaic module is a glass substrate 10, the front surface as shown in FIG. EVA 20, the cell 30, the back side is composed of the EVA 40, the backsheet (Backsheet) 50, the solar cell module having such a structure by utilizing the EVA polymer material solar The heat generated from the photovoltaic module itself and the heat dissipation effect of the peripheral devices are low, making it the biggest obstacle to solar power generation.

On the other hand, various techniques have been developed and applied for a solution to solve the problems as described above, as a representative patent in the Republic of Korea Patent Publication No. 10-0867655 as shown in FIG. The solar cell module having the structure in which the cell 120 and the glass plate 130 are mounted, and the insulating material 160 is filled in the space between the solar cell 120 and the bottom surface of the main body 110 is disclosed. . The glass plate 130 in the solar cell module having the structure as described above covers the solar cell 120 serves to protect the cell from being contaminated or damaged, and the heat absorbing plate 170 is exposed. Although the heat generated from the cell 120 is transmitted to cool the cell 120 by the cooling fluid flowing in the cooling pipe 150, the structure is configured to effectively prevent overheating of the cell 120, but the cooling fluid By installing the cooling pipe 150 flowing in the solar module, the weight of the module is not only limited to the installation place of the module, but also the complicated structure of the module is difficult to manufacture, and stores the cooling fluid There were problems such as having to provide a place for installing the tank separately.

In addition, as a patent of a technology having a simple structure that the above problems are complemented, as shown in FIG. 4, Korean Patent Publication No. 2005-0094179, the solar cell 123 in the tempered glass plate 121 and the EVA resin 122 as shown in FIG. And a solar cell module having a heat conduction plate 124 for absorbing and dissipating heat inside the module where the cell 123 is generated on the lower surface of the EVA resin 122. The heat conduction plate 124 having a heat dissipation function is known, and mainly uses materials such as aluminum, copper, tin, stainless steel, etc. Corrosion may occur to the inside of the metal material of the heat conduction plate attached to the light emitting module, which may cause problems of deterioration of heat dissipation and durability of the heat conduction plate.

As such, the current module for solar photovoltaic is made of materials with high moisture resistance. The reason is that the crystalline polysilicon is very weak to moisture, and when it comes into contact with moisture, it turns into silica due to whitening phenomenon. Loss occurs, and even in the case of a metallic material sheet having a heat dissipation function, the inside of the metallic material is easily corroded by moisture in a high temperature and high humidity region. There is an urgent need for measures for the future.

Therefore, the present invention is to propose a direction to maximize the power generation efficiency of the module by lowering the temperature inside the module by lowering the heat of the photovoltaic module and its peripherals through the back-sola EVA having a heat dissipation function.

The present invention removes the backsheet from the conventional solar module and added a heat-resistant material such as Al ₂ O ₃ , copper, brass, stainless steel, iron, CNT, silver, etc. in the solar EVA has a heat dissipation solar EVA function of the structure As a module for photovoltaic generation, the internal temperature of the module for photovoltaic generation is lowered to maximize the power generation efficiency of the existing cell, and the structure is simpler than that of the conventional photovoltaic module so that the production cost can be reduced. An object of the present invention is to provide a photovoltaic module having an EVA layer having a heat dissipation characteristic.

In the present invention for achieving the above object in the solar power module,

The photovoltaic module is a laminated structure in the order of the glass substrate 10, the front solar EVA (20), the solar cell 30 and the rear solar EVA (40 '),

The solar cell EVA 40 ′ has a heat dissipating material powder, and a solar power module having an EVA layer having heat dissipation characteristics as a means for solving the problem.

However, the above-mentioned heat dissipating material powder added to the back surface EVA 40 'is a material having excellent thermal conductivity, such as aluminum, copper, brass, steel sheet, stainless steel, CNT, iron, silver, and metals having emissivity performance equivalent to those of these materials. It is preferable to select and use 1 type or more from powder.

In addition, the present invention by the above problem solving means is a solar photovoltaic module having a structure to give a heat dissipation function by adding a thermally conductive powder to the back side EVA in a state in which the backsheet is removed from the conventional photovoltaic module, Due to the heat dissipation effect of the back side solar EVA, the temperature inside the module for solar power generation is lowered to maximize the power generation and generation efficiency, and the change in power generation to a certain level regardless of the surface temperature change of the module for solar power generation. As it can be maintained, it can achieve 3 ~ 5% increase in annual power generation and 5 ~ 10% in summer.

In addition, the solar photovoltaic module according to the present invention has a merit of lowering the production cost due to its simple structure.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail with reference to Figs. 5 to 8, the configuration and easily understood by those in the field related to the photovoltaic industry in the detailed description and the accompanying drawings or Detailed descriptions of components and operations not directly related to the technical features of the present invention have been omitted.

5 is a view showing a cross-sectional structure of a photovoltaic module for providing a heat dissipation function to the back side EVA by removing the backsheet as an embodiment of the present invention.

In accordance with an embodiment of the present invention, as shown in FIG.

The photovoltaic module is a laminated structure in the order of the glass substrate 10, the front solar EVA (20), the solar cell 30 and the rear solar EVA (40 '),

The back side solar EVA 40 ′ is related to a solar power generation module (hereinafter referred to as a “heat dissipation EVA type module”) having an EVA layer having heat dissipation characteristics characterized by containing a heat dissipating material powder.

A typical solar photovoltaic module is a glass substrate 10, front surface EVA (20), solar cell (30), rear surface EVA (40), backsheet (50) as shown in FIG. Has a laminated structure, and the backsheet 50 itself made of a fluorine resin material serves to lower the heat dissipation or heat transfer function.

In addition, the existing photovoltaic module production process is not easy to change the process or change the material because each material at the same time using a vacuum crimping heat bonding method.

Therefore, the heat dissipation EVA type module according to the present invention replaces the existing rear solar EVA with the rear solar EVA having a heat dissipation function in the solar photovoltaic module in which the existing back sheet is removed, thereby improving heat dissipation effect and simple structure. It is a feature.

In the present invention, the heat dissipating material powder added to the back surface EVA 40 'is a material having excellent thermal conductivity, such as aluminum, copper, brass, steel, stainless steel, CNT, iron, silver, and metal powder having an emissivity performance equivalent to or higher than those of these materials. It is preferable to select and use 1 type or more among them.

And the back side solar EVA (40 ') is generally located on the back of the solar cell 30 serves as a buffer to prevent damage to the solar cell 30 in the present invention is located on the back of the solar module, It also serves as a backsheet that protects the shell cell 30 from the external environment by preventing moisture from penetrating from the rear side.

The heat-dissipating EVA module having the structure as described above according to the present invention was obtained through experiments that fall within the maximum 10 ℃ compared to the ambient temperature of the conventional solar module.

The heat dissipation EVA module having the above structure removes the existing backsheet 50 from the structure of the conventional solar module as shown in FIG. 5 and provides heat dissipation function instead of the conventional rear-side EVA 40. It is a module of the structure replaced with the back solar EVA (40 ') having, and all the work is done in the basic equipment and process for the existing photovoltaic manufacturing. In addition, the process can be improved at once, and furthermore, since the existing backsheet 50 is removed, the module can be improved so that the heat dissipation can be made more smoothly.

In the case of the module with a conventional heat dissipation sheet as described above has a heat dissipation effect of about 10 ℃ compared to the conventional solar module, but in the case of a heat dissipation EVA type module compared with a module with a conventional heat dissipation sheet Increase the effect by more than 1.5 times brings about the effect of lowering the surface temperature of the solar module for about 15 ℃ or more.

In the heat dissipation EVA module, the heat dissipating material powder added to the back side EVA 40 'is preferably mixed 10 to 20 parts by weight with respect to 100 parts by weight of the EVA resin. If the amount of the heat-dissipating material powder is less than 10 parts by weight, the thermal conductivity may not be properly expressed and the heat-dissipating effect may not be properly exhibited. There is a fear that problems such as short circuits may occur due to weakening, resulting in problems with durability or adhesion, or low voltage resistance.

Preferably, the heat dissipating metal powder has a particle size of 10 nm to 1,000 nm. If the particle size is less than 10nm, there is a fear that the heat dissipation is deteriorated or there is a problem in dispersibility, if the particle size exceeds 1,000nm, there is a fear that problems such as a drop in transparency, poor surface condition.

In the solar photovoltaic module according to the present invention, the thickness of the material constituting each layer is typically the thickness of the material applied to the module, the glass substrate 10, the front solar EVA 20, the solar cell 30, The thickness of the back surface EVA 40 'is preferably 1 to 5 mm, 0.1 to 2 mm, 0.15 to 0.3 mm, and 0.1 to 2 mm, respectively, and the thickness of each material is not necessarily limited to the thicknesses defined above. This can be adjusted appropriately to the needs of the consumer or the needs of the manufacturer.

For reference, each component material used in the photovoltaic module according to the present invention typically uses the same material as the material used in the conventional photovoltaic module, and briefly describes each component constituting the photovoltaic module. The explanation is as follows.

In the present invention, as a substrate for injecting sunlight into the solar cell 30 and protecting the solar cell 30, it is preferable to use a transparent or translucent tempered glass substrate or a synthetic resin substrate, and typically, glass More preferably, the substrate 10 is used.

In addition, the front or rear solar EVA (20) (40 ') is an essential material for maintaining the life of the solar module for 20 to 30 years, located on the front and rear of the solar cell 30 damage of the solar cell (30) As a protective layer to act as a buffer to prevent the, serves as an adhesive for bonding the glass substrate 10 which is a component to be bonded to the solar cell 30. In the present invention, the solar EVA 20, 40 ′ used in the protective layer is used as a sheet, and the material may be selected from EVA, EEA, fluorocarbon resin, or a resin having a performance equivalent to or higher.

In addition, the solar cell 30 is a semiconductor device that converts light into electricity. The minimum unit is called a cell, and since the voltage from one cell is usually 0.5 to 0.6 V, the voltage is very small. Modules are manufactured in the form of panels that can be connected in series to obtain voltages from several volts to several hundreds of volts.

Conventional photovoltaic modules consisting of such parts are laminated by laminating the parts and then vacuum-compressed by a laminator by a conventional method, and then the edge of the photovoltaic module is aluminum by a conventional method. It is manufactured so that it can withstand external shocks and have waterproofness by finishing with a finish.

For reference, the method of manufacturing a module according to the present invention is manufactured by a vacuum pressing method which is the same method as a method of manufacturing a module in a conventional solar module manufacturing process.

Hereinafter, the configuration of the present invention will be described in more detail based on the following examples, but the present invention is not necessarily limited only to the following examples.

1. Fabrication of heat dissipation effect measuring equipment for photovoltaic module

As shown in the photo of Figure 6, the facility for measuring the heat dissipation effect of the module for photovoltaic generation is a self-produced facility by the company, two solar modules for installation in an acrylic chamber, and the surface temperature of the acrylic chamber It is equipped with a surface measuring thermometer to measure temperature, an internal thermometer to measure the temperature inside the acrylic chamber, and a sensed temperature measuring instrument for measuring the temperature of the surface of two solar modules.

For reference, Figure 6 is a photograph taken a facility for measuring the heat radiation effect.

The heat dissipation effect measuring equipment of the solar power module having the structure as described above is a facility having the structure as shown in the photograph of FIG. 6, so that the power generation amount and voltage and current can be simultaneously measured using the solar module efficiency device. It is designed to control the internal temperature, and the measuring equipment used in the present invention is a surface temperature measuring apparatus at an experimental level.

2. Fabrication of solar photovoltaic module with heat dissipation function

(Example 1)

The heat dissipation EVA module of the glass substrate 10, the front solar EVA 20, the solar cell 30, and the rear solar EVA 40 'was laminated in this order.

The backside solar EVA 40 'was prepared by adding 10 parts by weight of aluminum powder having a particle size of 20 ± 10 nm to 100 parts by weight of EVA resin.

(Example 2)

A heat-dissipating EVA type module having the same structure as in Example 1 was prepared, wherein the back-side EVA 40 'was prepared by adding 20 parts by weight of aluminum powder having a particle size of 20 ± 10 nm to 100 parts by weight of EVA resin. One was used.

(Example 3)

A heat-dissipating EVA type module having the same structure as in Example 1 was prepared, but the metal powder added to the rear surface EVA 40 ′ is made of stainless steel powder having a particle size of 20 ± 10 nm based on 100 parts by weight of EVA resin. The thing prepared by adding a weight part was used.

(Example 4)

A heat dissipating EVA module having the same structure as that of Example 1 was prepared, but the metal powder added to the rear surface EVA 40 ′ is made of stainless steel powder having a particle size of 20 ± 10 nm based on 100 parts by weight of EVA resin. The thing prepared by adding a weight part was used.

(Comparative Example 1): Fabrication of existing structured module with heat dissipation sheet

In the module having the structure of the glass substrate 10, the front surface EVA (20), the front cell 30, the back surface EVA (40) and the back sheet 50 as shown in FIG. Removing and replacing the aluminum heat dissipation sheet was manufactured as a conventional photovoltaic module having a structure and used as a control for comparison with the module of Example 1 above.

In addition, the thicknesses of the glass substrate 10, the front solar EVA 20, the solar cell 30, and the rear solar EVA 40, 40 ′, which are the laminated materials used in Examples 1 to 4 and Comparative Example 1, were used. Were 2 ± 0.1 mm, 1.5 ± 0.1 mm, 0.2 ± 0.05 mm, and 1.5 ± 0.1 mm, respectively, and the heat dissipation sheet of Comparative Example 1 was 0.3 ± 0.1 mm.

3. Measurement of heat dissipation effect of module for solar power generation

The surface temperature of the photovoltaic module of Examples 1 to 4 according to the present invention is clear in April using Comparative Example 1, which is a conventional photovoltaic module having a structure defined in 2 above, as a control module. The results of the average value of the heat dissipation effect based on the relative temperature difference for the control module were measured after 10 days for each day (from 9 to 5 o'clock). The results are shown in Table 1 below.

(Unit: ℃) division
Example Comparative example Remarks
One 2 3 4 One Heat dissipation effect -6 to -11 -8 to -14 -4 to -6 -5 to -9 -5 to -10 Module reference temperature
20 ~ 90 ℃

According to the contents of [Table 1], according to the contents of [Table 2], in the case of Examples 1 to 4, all of the heat dissipation effect was found to be better than Comparative Example 1.

In addition, the heat dissipation effect was better than Examples 1 and 2 in which the aluminum powder was added to the back surface EVA 40 'and Examples 3 and 4 in which the bivalent stainless steel powder were added.

In addition, in the case of Example 2 using the aluminum powder was shown that the heat dissipation effect is better by adding a lot of aluminum powder than Example 1, and falling further up to 4 ~ 5 ℃ compared to Comparative Example 1 It was confirmed through, and in the case of Example 4 to which the stainless steel powder was added, it was shown that the heat dissipation effect is better than Example 3.

For reference, Figure 7 is compared with the surface temperature of the photovoltaic modules of Examples 1 and 2, which are provided with a heat dissipation function in Comparative Example 1 and a solar cell back EVA having a heat dissipation function of Comparative Example 1 having a heat dissipation sheet It is related with the graph which shows the average value which measured the temperature change.

According to Comparative Example 1 and the present invention which is a conventional solar module for applying a heat radiation sheet As a graph showing the average value measured the temperature change with the surface temperature of the module over time for the photovoltaic modules of Example 1 and Example 2 equipped with a back solar EVA having a heat dissipation function, Comparative Example It can be seen that the surface temperature of 1 is the highest, the surface temperature of Example 1 is the next highest, and the surface temperature of Example 2 is the lowest.

4. Measurement of the amount of power generated by the heat dissipation effect of the monthly photovoltaic module

The result of measuring the amount of power generation according to the monthly heat dissipation effect using the solar power module of Example 2 according to the present invention is the same as the contents of the graph shown in FIG. 8, and the monthly heat dissipation effect of the conventional solar power module In comparison with the graph of FIG. 1 showing the result of measuring the amount of power generated according to the present Example 2 shows the same or better than the conventional photovoltaic power generation in April and November, the temperature is cool, especially In the case of the high temperature of August, the surface temperature of the conventional module is 87.5 ° C., and the efficiency of photovoltaic power generation is only 12% as shown in the graph shown in FIG. As a result of the graph shown in Figure 8 it can be seen that the temperature of the module surface is only 71.2 ℃ maximum, the photovoltaic power generation efficiency is also improved to 15%.

For reference, Figure 8 relates to a graph showing the efficiency of the power generation according to the monthly standard heat dissipation effect of the solar module according to the present invention.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention described in the claims below. It will be appreciated.

1 is a graph showing the amount of photovoltaic power generation according to the amount of sunshine per month by a conventional photovoltaic module,

2 is a view showing a cross-sectional structure of a conventional photovoltaic module,

3 is a view showing a cross-sectional structure of a conventional solar module for solar,

4 is a view showing a cross-sectional structure of another conventional solar module for solar,

5 is a view showing a cross-sectional structure of a photovoltaic module for providing a heat dissipation function to remove the backsheet and backside EVA as an embodiment of the present invention;

Figure 6 is a photograph taken a facility for measuring the heat dissipation effect,

FIG. 7 is a graph showing an average value of measuring a temperature change with a surface temperature of a conventional solar module having a heat dissipation sheet and a solar power module having a heat dissipation function on the rear side solar EVA having a heat dissipation function;

Figure 8 relates to a graph showing the efficiency of the power generation according to the monthly standard heat dissipation effect of the solar module according to the present invention.

Explanation of symbols on the main parts of the drawings

10: glass substrate 20: front shoot EVA

30: Cell 40, 40 ': Rear shoot EVA

50: Backsheet

Claims (3)

In the solar module, The photovoltaic module is a laminated structure in the order of the glass substrate 10, the front solar EVA (20), the solar cell 30 and the rear solar EVA (40 '), The rear side solar EVA (40 ') is a module for solar cells having an EVA layer having heat dissipation characteristics, characterized in that it contains a heat dissipating material powder. The method of claim 1, The heat dissipating material powder is a material having excellent thermal conductivity, and may be selected from one or more of aluminum, copper, brass, steel, stainless steel, CNT, iron, silver, and metal powder having emissivity performance equivalent to those of these materials. Solar photovoltaic module having an EVA layer having heat dissipation characteristics. The method according to claim 1 or 2, The heat dissipating material powder is added to 10 to 20 parts by weight with respect to 100 parts by weight of the EVA resin, the solar cell module having an EVA layer having a heat dissipation characteristics, characterized in that uniformly mixed.

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