KR102378110B1 - Concentrated solar ray generation device and method for solar ray generation using the same - Google Patents

Abstract

The present invention relates to a photovoltaic power generation method using the same. In one embodiment, the light-collecting type photovoltaic device includes a light-collecting means for condensing sunlight; a parallel light means for collimating the focused sunlight; a prism positioned at the rear end of the parallel light means to split the collimated sunlight; an optical member positioned at the rear end of the prism to condense the split sunlight without overlapping by wavelength; and a solar cell generating electrical energy using the concentrated sunlight.

Description

Concentrating solar power generation device and solar power generation method using the same

The present invention relates to a concentrating solar power generation device and a solar power generation method using the same.

In order to increase the efficiency of use of solar energy, a technology for increasing the electrical energy conversion efficiency of the solar energy in the wave field region and the thermal energy efficiency in the infrared region through light collection is being studied. 1 shows the energy distribution according to the wavelength of sunlight. Referring to FIG. 1, when the solar energy reaching the earth's surface is divided by wavelength and the energy weight is divided into ultraviolet, visible, and infrared regions, the ultraviolet region is about 5%, the visible ray region is about 43%, and the infrared region is about It accounts for 52%, and solar power is mainly generated in the visible light area.

Photovoltaic cells (or solar cells, photovoltaic cells) used in photovoltaic power generation are sensitive to wavelengths in the visible and near-infrared regions. A lot of energy can be condensed and high heat can occur. However, solar cells are generally vulnerable to heat, and when exposed to high heat, problems such as reduced efficiency, reduced lifespan, and damage may occur.

To solve this problem, attach a heat sink to the back of the solar cell or use a prism or a spectrum separator to separate the light in the ultraviolet and infrared region to solve the problem of overheating of the solar cell and try to utilize it as thermal energy. is being done

In addition, when the light source is spectrally separated using a plurality of beam splitters, the spectrum overlap problem due to the prism can be prevented as described above, but the economic burden due to the use of an expensive beam splitter and the complexity of the device are increased. was becoming a problem.

As a prior art related to the present invention, it is disclosed in Republic of Korea Patent Publication No. 1043237 (published on June 21, 2011, title of the invention: condensing solar cell module).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photovoltaic device having excellent solar light collection and power generation efficiency.

Another object of the present invention is to provide a concentrating solar power generation device having excellent space efficiency and economical efficiency.

Another object of the present invention is to provide a concentrating photovoltaic device capable of preventing overheating and damage of the concentrating photovoltaic device.

Another object of the present invention is to provide a photovoltaic power generation method using the concentrating photovoltaic device.

One aspect of the present invention relates to a concentrating solar photovoltaic device. In one embodiment, the light-collecting type photovoltaic device includes a light-collecting means for condensing sunlight; a parallel light means for collimating the focused sunlight; a prism positioned at the rear end of the parallel light means to split the collimated sunlight; an optical member positioned at the rear end of the prism to condense the split sunlight without overlapping by wavelength; and a solar cell generating electrical energy using the concentrated sunlight.

In one embodiment, the photovoltaic device may further include a heat exchange device that generates heat using the focused sunlight.

In one embodiment, the photovoltaic device may further include a reflecting means for reflecting the concentrated sunlight and the diffusely reflected sunlight to the heat exchange device.

In one embodiment, the light collecting means and the parallel light means may include at least one of a parabolic reflector, a concave lens, a convex lens, and a Fresnel lens, respectively.

In one embodiment, the optical member may be a convex lens.

Another aspect of the present invention relates to a photovoltaic power generation method using the photovoltaic device. In one embodiment, the photovoltaic power generation method comprises: concentrating sunlight using a light collecting means; collimating the focused sunlight using a parallel light means; splitting the collimated sunlight; condensing the divided sunlight without overlapping by wavelength; and generating electrical energy using the concentrated sunlight.

In one embodiment, the method may further include; generating thermal energy using one or more of the concentrated sunlight and diffusely reflected sunlight.

The photovoltaic device of the present invention can prevent overlapping of photovoltaic spectra when condensing, so it has excellent photovoltaic light concentrating efficiency, and has excellent space efficiency by enabling miniaturization and simplification of the device, and has a direct effect on photovoltaic power generation. The wavelength band that cannot be provided can be separated and used separately to prevent overheating and damage of the photovoltaic device, while providing excellent economic feasibility.

1 shows the energy distribution according to the wavelength of sunlight.
2 is a view showing a concentrating solar power generation device according to an embodiment of the present invention.
3 is a view showing a concentrating solar power generation device according to another embodiment of the present invention.
4 is a view showing a concentrating solar power generation device according to another embodiment of the present invention.
5 is a view showing a concentrating solar power generation device according to another embodiment of the present invention.
6 shows a heat exchange device according to an embodiment of the present invention.
7 shows a heat exchange device according to another embodiment of the present invention.
8 is a graph showing the wavelength-specific spectroscopy of the photovoltaic device of a comparative example for the present invention.
9 is a view showing the spectrum of each wavelength of the light-concentrating photovoltaic device of the embodiment according to the present invention.

In describing the present invention, if it is determined that a detailed description of a related known technology or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

And the terms to be described later are terms defined in consideration of the functions in the present invention, which may vary depending on the intention or custom of the user or operator, so the definition should be made based on the content throughout this specification describing the present invention.

Meanwhile, in the present specification, short-wavelength light means light in the ultraviolet region, meaning a region having a wavelength of less than 380 nm, and medium-wavelength light is light in the visible region, and a region having a wavelength of 380 nm or more to 700 nm or less. means, and long-wavelength light is light in the infrared region, and is defined to mean a region of sunlight having a wavelength of 700 nm or more.

Concentrating solar power generation device

One aspect of the present invention relates to a concentrating solar photovoltaic device. 2 is a view showing a concentrating solar power generation device 100 according to an embodiment of the present invention. Referring to FIG. 2 , the light-concentrating solar power generation device 100 includes a light-collecting means 10 for condensing sunlight; a parallel light means 20 for collimating the focused sunlight; a prism 30 positioned at the rear end of the parallel light means 20, and for splitting the collimated sunlight; an optical member 40 positioned at the rear end of the prism 30 and condensing the split sunlight without overlapping for each wavelength; and a solar cell 50 for generating electrical energy using the concentrated sunlight.

condensing means

The light collecting means 10 is included for the purpose of condensing incident sunlight. In one embodiment, the light collecting means 10 may use a conventional one. For example, a convex lens as shown in FIG. 3 may be used, or one or more of a parabolic reflecting collar, a concave lens, and a Fresnel lens may be used. A conventional Fresnel lens may be used. For example, a pattern in which concentric circles are formed and a cross section of which is in a sawtooth shape is formed may be used. When the Fresnel lens is applied as the light collecting means 10 , the light collecting efficiency may be excellent. The material of the light collecting means 10 may be plastic or glass.

Referring to FIG. 2 , the light collecting means 10 may use a linear convex lens.

3 shows a light-concentrating solar power generation device 200 according to another embodiment of the present invention. Referring to FIG. 3 , the light collecting means 11 may use a parabolic reflector.

4 shows a light-concentrating solar power generation device 300 according to another embodiment of the present invention. Referring to FIG. 4 , in one embodiment, the light collecting means 12 may use a circular parabolic reflector. In another embodiment of the present invention, the light collecting means may use a rectangular parabolic reflector.

parallel light means

The parallel light means 20 emits the concentrated sunlight It is included for the purpose of parallelizing. Referring to FIG. 2 , the sunlight passing through the condensing means 10 refracts and converges to a focal point, and then proceeds to reach the parallel light means 20 . The sunlight passing through the parallel light means 20 is refracted so that the rays are parallelized, and the transmission diameter may not change even if the rays continue to progress. In one embodiment, as the parallel light means 20, a conventional one may be used. At least one of a parabolic reflecting collar, a concave lens, and a Fresnel lens may be used. 4 and 5, in one embodiment, the parallel light means 21 may use a parabolic reflector. The material of the parallel light means 21 may be plastic or glass.

prism

The prism 30 is included for the purpose of splitting the collimated sunlight through the parallel light means 20 . The sunlight passing through the prism 30 may be split in the form of a surface light source.

optical member

In the present invention, the optical member 40 is provided at the rear end of the prism 30 , and is included for the purpose of condensing sunlight divided by the prism 30 for each wavelength. When the optical member 40 is provided at the rear end of the prism 30 of the present invention as shown in FIG. 2 , the sunlight split by the prism 30 in the form of a surface light source is condensed in the form of a point light source to obtain a solar spectrum. It is possible to collect light without overlap for each wavelength. Therefore, compared to the existing solar power generation device, the prism (30) ?? Since the distance between the solar cells 50 may be made close, it may be possible to miniaturize and simplify the device.

In addition, since light is collected without overlap for each wavelength, the use area of the expensive solar cell 50 to be described later can be minimized, and the power generation efficiency of the solar cell can be increased, and overheating and damage of the photovoltaic device can be prevented, Efficient thermal power generation may be possible through the concentrated sunlight.

In one embodiment, the optical member 40 may be a convex lens. For example, it may be a linear convex lens. When the convex lens is used, it is condensed without overlap for each wavelength, so it is possible to minimize the use area of the expensive solar cell 50, which will be described later, and to prevent overheating and damage of the photovoltaic device while increasing the power generation efficiency of the solar cell. It is possible to minimize the space size of the photovoltaic device due to the shortening of the condensing distance, and efficient thermal power generation may be possible through the condensed sunlight.

solar cell

The solar cell 50 may generate electric energy by using the concentrated sunlight.

As the solar cell 50, a conventional one may be used. For example, the solar cell 50 may use a semiconductor device that directly converts light energy into electrical energy using the photoelectric effect, which may be composed of a semiconductor thin film having polarity of (+) and (-), respectively. can That is, when sunlight corresponding to the medium wavelength light (visible light) region is incident on the solar cell, electrons and holes are generated inside the solar cell, and electric charges move to the P and N poles of the solar cell 50 , respectively. . Due to this phenomenon, a potential difference is generated between the P pole and the N pole, and at this time, when a load is connected to the solar cell 50 , a current may flow. In one embodiment, the solar cell 50 may be provided in the ultraviolet region among the concentrated sunlight. In one embodiment, the solar cell 50 may be provided at an incident position of sunlight corresponding to a sensitive absorption wavelength using different absorption wavelength bands.

In one embodiment, the solar cell 50 may use one that is sensitive to a wavelength of 300 nm to 3 μm. For example, it may be a region having a wavelength of 380 nm or more to 1600 nm or less. For another example, it may be a region having a wavelength of 400 nm or more to 1400 nm or less.

Referring to FIG. 2 , the concentrating photovoltaic power generation device 100 according to an embodiment of the present invention may further include a heat exchange device 60 for generating heat by using the condensed sunlight.

heat exchanger

The heat exchange device 60 may be included for the purpose of generating heat using one or more of the concentrated sunlight and diffusely reflected sunlight. When the heat exchange device 60 is included, it is possible to use sunlight and solar heat at the same time, so that solar energy can be efficiently used. Referring to FIG. 3, in one embodiment of the present invention, the heat exchange device 60 is provided in a region where sunlight of medium wavelength (visible light) and long wavelength (infrared) light is incident among the concentrated sunlight. , it is possible to generate heat by using sunlight in the mid-wavelength light (visible light) and long-wavelength light (infrared light) region. For example, a wavelength of 650 nm or more can be used. As another example, a wavelength of 650 nm to 5 μm may be used. As another example, a wavelength of 700 nm to 5 μm may be used.

Referring to FIG. 2 , in one embodiment of the present invention, the light-concentrating solar power generation device reflects at least one of the sunlight collected from the optical member 40 and the diffusely reflected sunlight to the heat exchange device 60 . It may further include a reflecting means (70); and the sunlight reflected by the reflecting means (70) and incident on the heat exchange device (60) to generate heat.

5 shows a concentrating solar power generation device 400 according to another embodiment of the present invention. Referring to FIG. 5 , the concentrating solar power generation device 400 may further include a beam splitter and a long wavelength region reflector, so as to generate solar power by splitting the parallel light into long wavelength light, short wavelength light and medium wavelength light. More specifically, a beam splitter is provided at the rear end of the collimating lens 21 to separate medium wavelength light (visible light) and short wavelength light (ultraviolet light) regions from the sunlight collimated by the parallel light means 21, A long wavelength (infrared) reflector provided at the rear end of the beam splitter may be used to split the spectrum into a long wavelength region. The concentrated medium-wavelength light is incident on the solar cell 50 and can generate electrical energy using the medium-wavelength light, and the long-wavelength light reflected by the long-wavelength reflector is condensed for each wavelength through the optical member 40. It is incident on the heat exchange device 60 , and the short-wavelength light is reflected through the reflecting means 70 , and is incident on the heat exchange device 60 . The heat exchanger (60) may generate heat using the sunlight.

6 shows a heat exchange device according to an embodiment of the present invention. Referring to FIG. 6 , the heat exchange device 60 may have a rectangular cylindrical structure in which a space of a certain size is provided. In a specific embodiment, the inside of the heat exchange device 60 is provided with an inlet (not shown) through which the heat exchange medium flows in the lower portion so that the heat exchange medium can enter and exit, and an outlet (not shown) through which the heat exchange medium flows out at the upper portion. This may be provided. The inlet and outlet may be made of a flexible material. In a specific embodiment, a heat insulating member 64 such as a heat insulating cover may be installed outside the heat exchange device 60 . In addition, a pump may be installed inside the heat exchange device 60 to forcibly circulate the heat transfer medium. In addition, as shown in FIG. 6 , a plurality of solar cells 51 and 52 may be provided on at least one surface of the heat exchange device 60 . In this case, as described above, the solar cells 51 and 52 may be provided at the incident position of sunlight corresponding to the absorption wavelength to which it is sensitive.

7 shows a heat exchange device 61 according to another embodiment of the present invention. Referring to FIG. 7 , in order to utilize at least one of the concentrated sunlight, such as long-wavelength light and short-wavelength light, and diffusely reflected sunlight, a reflecting means 71 is attached to one side to reflect the diffusely reflected sunlight. Thus, it can be incident on the heat exchange device (61). In one embodiment, short-wavelength light (ultraviolet rays) among the diffusely reflected sunlight may be utilized.

The concentrating solar power generation device of the present invention has excellent solar light collection efficiency by preventing overlapping of spectra during light collection, excellent space efficiency by simplifying the device, and a wavelength band that does not directly affect solar power generation It is possible to prevent overheating and damage of the photovoltaic device by separating it and using it separately. In addition, since the device commonly used for the concentrating solar power and the concentrating solar system is shared, the manufacturing cost can be lowered, and the unit cost per energy output of the solar/thermal facility can be reduced, the facility investment cost and the investment recovery period can be shortened. can

Another aspect of the present invention relates to a photovoltaic power generation method using the concentrating photovoltaic device. In one embodiment, the photovoltaic power generation method comprises: concentrating sunlight using a light collecting means; collimating the focused sunlight using a parallel light means; splitting the collimated sunlight; condensing the divided sunlight without overlapping by wavelength; and generating electrical energy using the concentrated sunlight.

In one embodiment, the photovoltaic power generation method, generating thermal energy by using one or more of concentrated sunlight and diffusely reflected sunlight; may further include. Referring to FIG. 2 , in one embodiment of the present invention, heat energy may be generated by reflecting the scattered sunlight to the heat exchange device 60 through the reflecting means 70 .

Example and comparative example

Example

The light condensing means 10 including a convex lens for condensing sunlight, the parallel light means 20 including a convex lens for collimating the collected sunlight, and the parallel light means 20 are provided at the rear end of the collimated light An optical member (linear convex lens) that is provided at the rear end of the prism 30 for splitting sunlight, is provided at the rear end of the prism 30, is positioned at the rear end of the prism 30, and condenses the sunlight split from the prism 30 without overlap for each wavelength , 40), a solar cell 50 that is provided in a medium wavelength light (visible light) region among the concentrated sunlight and generates electrical energy using the medium wavelength light, and is provided in a long wavelength light (infrared) region of the concentrated sunlight 2, including a heat exchange device 60 for generating heat using the long-wavelength light, and a reflecting means 70 for reflecting short-wavelength light (ultraviolet rays) among the concentrated sunlight to the heat exchange device 60. A light-concentrating photovoltaic device 100 was manufactured.

comparative example

The same solar power generation device as in the above example was manufactured except that the convex lens was not included at the rear end of the prism.

8 is a graph showing the wavelength-specific spectroscopy of a comparative example photovoltaic device according to the present invention. Referring to FIG. 8 , when the light incident on the prism is not a point light source, the spectrum overlaps or the spectrum is separated at a very long distance in the process of spectrum separation using the prism. It was found that the configuration of the power generation device becomes difficult, the light collection efficiency is lowered, and wavelengths such as long-wavelength light (infrared) are received by the solar cell due to spectral overlap, and there is a risk of overheating and damage.

9 is a view showing the spectrum of each wavelength of the light-concentrating photovoltaic device of the embodiment according to the present invention. In this case, FIG. 9 shows only a specific wavelength, and actual light collection may appear in the form of a continuous spectrum for each wavelength. Referring to FIG. 9, when an optical member (convex lens) is added to the rear end of the prism of the present invention, spectral overlap can be prevented and light can be focused by wavelength, thereby increasing the power generation efficiency of the solar cell and overheating of the photovoltaic device And it was found that the damage phenomenon can be prevented, and thermal power generation can be possible using wavelengths in the ultraviolet and infrared regions.

Simple modifications or changes of the present invention can be easily carried out by those of ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

10, 11, 12: light collecting means 20, 21: parallel light means
30: prism 40: optical member
50, 51, 52: solar cell 60, 61: heat exchange device
64: insulation member
70, 71: reflection means
100, 200, 300, 400: Concentrating solar power generation device

Claims (7)

Condensing means for condensing sunlight;
a parallel light means for collimating the focused sunlight;
a prism positioned at the rear end of the parallel light means to split the collimated sunlight;
an optical member positioned at the rear end of the prism to condense the split sunlight in the form of a surface light source in the form of a point light source without overlap for each wavelength;
a solar cell for generating electrical energy by using visible light among the concentrated sunlight;
a heat exchange device for generating heat using infrared rays among the concentrated sunlight; and
and reflecting means for reflecting at least one of ultraviolet rays and diffusely reflected sunlight among the concentrated sunlight to the heat exchange device;
The optical member is a condensing photovoltaic device, characterized in that the convex lens.
delete delete According to claim 1, wherein the light condensing means and the parallel light means, respectively, the light converging type photovoltaic device, characterized in that using at least one of a parabolic reflector, a concave lens, a convex lens, and a Fresnel lens.
delete It is a photovoltaic power generation method using the concentrating photovoltaic device of claim 1,
Concentrating sunlight using a light collecting means;
collimating the focused sunlight using a parallel light means;
splitting the collimated sunlight using a prism;
condensing the split solar light in the form of a surface light source in the form of a point light source without overlap by wavelength using an optical member; and
Solar power generation comprising a; generating electrical energy in a solar cell using light in the visible region among the collected sunlight, and generating thermal energy in a heat exchange device using light in the infrared region among the collected sunlight is a method,
The optical member is a convex lens,
At least one of the light in the ultraviolet region and diffusely reflected sunlight among the concentrated sunlight,
Photovoltaic power generation method, characterized in that it is reflected to the heat exchange device by the reflecting means of the photovoltaic device to generate thermal energy.

delete

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