JP2013110356A - Solar cell module and solar light power generation apparatus - Google Patents

Abstract

Provided are a solar cell module and a solar power generation apparatus using the same, which can suppress a decrease in the light collecting function due to use and can exhibit an excellent light collecting function over a long period of time.
A light collecting member that absorbs light incident from the outside by phosphors and propagates light emitted from the phosphors and emits the light from at least one end surface 2c, and a light collecting member. The solar cell module 1 includes a solar cell element 3 that is installed on the end surface 2c of the optical member 2 and receives power emitted from the end surface 2c to generate electric power. The phosphor comprises an organic phosphor 8 and an inorganic phosphor 7, and at least one of the inorganic phosphors 7 is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits light.
[Selection] Figure 1

Description

  The present invention relates to a solar cell module and a solar power generation device.

  A solar power generation device described in Patent Document 1 is installed as a solar power generation device that generates power by installing a solar cell element on an end surface of a light guide and making light propagated through the light guide enter the solar cell element. Solar energy recovery windows) are known. This solar power generation device is a window-type solar power generation device using a light guide as a window, and a part of sunlight incident from one main surface of the light guide is propagated inside the light guide. It is comprised so that it may guide to a solar cell element. A phosphor is applied to the surface of the light guide, and the phosphor is excited and emits light by sunlight incident on the light guide. Light (fluorescence) radiated from the phosphor propagates through the light guide and enters the solar cell element to generate power.

  Further, Patent Document 2 discloses a flat light collector in which a plurality of light collecting plates in which a fluorescent paint is dispersed in a transparent plate is laminated, and the light collecting plate closer to the light incident side has a shorter absorption wavelength of the fluorescent dye. Thus, there has been proposed a structure that increases the amount of light collected per unit area.

JP-A-3-273686 JP-A 63-159812

  By the way, in the solar power generation device of Patent Document 1 and the flat light collector of Patent Document 2, phosphors are used for the purpose of concentrating sunlight, but as phosphors, as many wavelengths as possible in sunlight. Since it is desirable to be able to use this light, organic phosphors excellent in such performance are mainly used. Inorganic phosphors have a lower fluorescence quantum yield than organic phosphors, and because of their large particle size, they cause scattering and disturb the light guide. Therefore, organic phosphors have been used more favorably in the past. ing.

  However, organic phosphors have energy for dissociating bonds between atoms in the wavelength region of ultraviolet light, and are deteriorated by breaking bonds between atoms by ultraviolet light. Degraded phosphor molecules do not exhibit the physical properties of the target phosphor and will interfere with light collection. Therefore, they are used in solar power generation devices and concentrators using such organic phosphors. As a result, the light collecting function is greatly reduced.

  The present invention has been made in view of the above circumstances, and the object thereof is a solar cell that suppresses a decrease in the light collecting function accompanying use and can exhibit an excellent light collecting function over a long period of time. A module and a solar power generation apparatus using the module are provided.

  In order to achieve the above object, the solar cell module of the present invention absorbs light incident from the outside by the phosphor, propagates the light emitted from the phosphor inside, and emits the light from at least one end face. And a solar cell element that receives light emitted from the end face and generates electric power, and the phosphor includes an organic phosphor and an inorganic phosphor. And at least one of the inorganic phosphors is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits light.

  Moreover, the said solar cell module WHEREIN: The said condensing member is what the said fluorescent substance was disperse | distributed in the transparent base material, It is characterized by the above-mentioned.

  In the solar cell module, the concentration of the ultraviolet light absorbing phosphor on the side opposite to the light incident surface side is higher than the concentration of the ultraviolet light absorbing phosphor on the light incident surface side. It is characterized by being higher than

  Moreover, the said solar cell module WHEREIN: The said condensing member is provided with the fluorescent substance layer formed by disperse | distributing the said fluorescent substance on the transparent base material surface, It is characterized by the above-mentioned.

  Moreover, the said solar cell module WHEREIN: The said condensing member is a thing by which the transparent layer was provided in the surface on the opposite side to the said transparent base material of the said fluorescent substance layer, It is characterized by the above-mentioned.

  In the solar cell module, the light collecting member includes a first layer disposed on a light incident side, and a second layer disposed behind the first layer, and the first layer The layer has the inorganic phosphor, and the second layer has the organic phosphor.

  In the solar cell module, the light collecting member has a transparent layer between the first layer and the second layer, and the transparent layer is lower than a refractive index of the transparent base material of the second layer. It is characterized by a refractive index.

  Moreover, in the said solar cell module, the peak of the light emission wavelength of the said ultraviolet light absorption fluorescent substance exists in the long wavelength side rather than the peak of the absorption wavelength of another fluorescent substance, It is characterized by the above-mentioned.

  The solar cell module is characterized by having a quantum dot phosphor as the inorganic phosphor.

  The solar power generation device of this invention is equipped with the said solar cell module, It is characterized by the above-mentioned.

  According to the present invention, the light collecting member has an organic phosphor and an inorganic phosphor, and at least one of the inorganic phosphors is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits light. When the phosphor absorbs the ultraviolet light in the incident light and emits light, the organic phosphor suppresses the absorption of the ultraviolet light, and thus the deterioration is suppressed. As a result, the condensing member is prevented from deteriorating the condensing function with use, and thus the solar cell module having the condensing member and the solar power generation apparatus using the solar cell module have an excellent condensing function over a long period of time. To come out.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the solar cell module which concerns on this invention, (a) is a perspective view which shows schematic structure of a solar cell module, (b) is principal part sectional drawing of (a). It is a figure which shows a sunlight spectrum. It is a spectrum figure which shows the characteristic of an ultraviolet light absorption fluorescent substance (inorganic fluorescent substance). (A), (b) is a principal part sectional side view which shows the modification of 1st Embodiment. It is principal part sectional drawing of 2nd Embodiment of the solar cell module which concerns on this invention. It is a figure which shows 3rd Embodiment of the solar cell module which concerns on this invention, (a) is a perspective view which shows schematic structure of a solar cell module, (b) is principal part sectional drawing of (a). It is a figure which shows a sunlight spectrum after ultraviolet light was absorbed with the inorganic fluorescent substance. (A)-(c) is a principal part sectional side view which shows the modification of 3rd Embodiment. (A)-(c) is principal part sectional drawing which shows another modification of 3rd Embodiment. (A), (b) is principal part side sectional drawing which shows the modification of 3rd Embodiment shown in FIG. (A) is a principal part sectional drawing of 4th Embodiment of the solar cell module which concerns on this invention, (b) is a principal part sectional side view which shows a modification. It is explanatory drawing of a Forster mechanism. It is explanatory drawing of a Forster mechanism. (A) is principal part sectional drawing of 5th Embodiment of the solar cell module which concerns on this invention, (b) is principal part sectional drawing which shows a modification. It is a figure which shows the light emission characteristic of inorganic fluorescent substance, and the absorption characteristic of organic fluorescent substance. (A), (b) is a schematic diagram for demonstrating the efficiency by which the light which the inorganic fluorescent substance light-emitted is guided. It is a schematic block diagram of a solar power generation device.

The present invention will be described in detail below. In the following drawings, the scale of each component is appropriately changed in order to make each component recognizable.
[First Embodiment]
Fig.1 (a) is a perspective view which shows schematic structure of 1st Embodiment of the solar cell module which concerns on this invention, FIG.1 (b) is principal part side sectional drawing of Fig.1 (a).

As shown in FIGS. 1A and 1B, the solar cell module 1 is a solar that receives light emitted from a rectangular plate-shaped light collecting plate 2 (light collecting member) and a first end surface 2 c of the light collecting plate 2. The battery element 3 is provided with a frame body 4 that integrally holds the light collector 2 and the solar battery element 3.
The light collector 2 includes a first main surface 2a serving as a light incident surface, a second main surface 2b opposite to the first main surface 2a, the first end surface 2c serving as a light exit surface, and other end surfaces. It has. In the present embodiment, the reflective layer 5 is provided on the end face other than the first end face 2c.

  The light collector 2 has a plurality of types of phosphors dispersed in a transparent substrate 6 made of a highly transparent organic material such as acrylic resin such as PMMA, polycarbonate resin, or transparent inorganic material such as glass. Is. The phosphor is an optical functional material that absorbs ultraviolet light or visible light, and emits and emits visible light or infrared light. In this embodiment, as shown in FIG. Both bodies 8 are used and are distributed almost uniformly in the transparent substrate 6. Note that visible light is light in a wavelength region of 380 nm to 750 nm, ultraviolet light is light in a wavelength region less than 380 nm, and infrared light is light in a wavelength region larger than 750 nm.

  Among the dispersed phosphors, the inorganic phosphor 7 is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits visible light or infrared light having a wavelength of about 500 nm to 600 nm or more in this embodiment. It is used. In addition, the organic phosphor 8 that emits visible light having a wavelength longer than the wavelength absorbed and absorbed by visible light is used. In the present embodiment, the first organic phosphor 8a and the second organic phosphor 8b are used. And are used.

Specifically, in the present embodiment, a rare earth phosphor [BaMg ₂ Al ₁₆ O ₂₇ : Eu] having an emission peak at a wavelength of 515 nm is used as the inorganic phosphor 7 (ultraviolet light absorbing phosphor). Further, as the first organic phosphor 8a of the organic phosphor 8, Lumogen F Yellow 083 (trade name) manufactured by BASF showing a light emission peak at a wavelength of 490 nm is used, and as the second organic phosphor 8b, a light emission peak at a wavelength of 578 nm. Lumogen F Red 305 (trade name) manufactured by BASF is used. These phosphors 7 and 8 (8a and 8b) are not particularly limited, and are mixed at a predetermined ratio set in advance, and are mixed into the material of the transparent substrate 6 when the light collector 2 is molded. Are evenly distributed.

In the present invention, the inorganic phosphor 7 and the organic phosphor 8 are not limited to those described above, and various types can be used.
For example, as the inorganic phosphor 7, red phosphors GdBO ₃ : Eu, Gd ₂ O ₃ : Eu, Gd ₂ O ₂ S: Eu, Gd ₃ Al ₅ O ₁₂ : Eu, Gd ₃ Ga ₅ O _{12 : Eu, GdVO 4: Eu,} Gd 3 Ga 5 O 12: Ce, Cr, Y 2 O 3: Eu, Y 2 O 2 S: Eu, La 2 O 3: Eu, La 2 O 2 S: Eu, InBO ₃ : Eu, (Y, In) BO ₃ : Eu, etc., and Gd ₂ O ₃ : Tb, Gd ₂ O ₂ S: Tb, Gd ₂ O ₂ S: Pr, Gd ₃ Al ₅ , which are green phosphors. _{O 12: Tb, Gd 3 Ga} 5 O 12: Tb, Y 2 O 3: Tb, Y 2 O 2 S: Tb, Y 2 O 2 S: Tb, Dy, La 2 O 2 S: Tb, ZnS: Cu ZnS: Cu, Au, Zn ₂ SiO ₄ : Mn, InBO ₃ : Tb, MgGa ₂ O ₄ : Mn, and the like, and further phosphors that emit blue light, such as YAlO ₃ : Ce, Y ₂ SiO ₅ : Ce, Gd ₂ SiO ₅ : Ce, YTaO ₄ : Nb, BaFCl: Eu, ZnS: Ag, CaWO ₄ , CdWO ₄ , ZnWO ₄ , MgWO ₄ , Sr ₅ (PO ₄ ) ₃ Cl: Eu, YPO ₄ : Cl, or the like is used.

  The organic phosphor 8 may be a coumarin dye, perylene dye, phthalocyanine dye, stilbene dye, cyanine dye, polyphenylene dye, xanthene dye, pyridine dye, oxazine dye, chrysene dye, thioflavine. Dyes, perylene dyes, pyrene dyes, anthracene dyes, acridone dyes, acridine dyes, fluorene dyes, terphenyl dyes, ethene dyes, butadiene dyes, hexatriene dyes, oxazole dyes, coumarins Dyes, stilbene dyes, di- and triphenylmethane dyes, thiazole dyes, thiazine dyes, naphthalimide dyes, anthraquinone dyes and the like are preferably used. Specifically, 3- (2′- Benzothiazolyl) -7-diethylaminocoumarin (bear) 6), 3- (2′-Benzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 7), 3- (2′-N-methylbenzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 30) , 2,3,5,6-1H, 4H-tetrahydro-8-trifluoromethylquinolidine (9,9a, 1-gh) coumarin (coumarin 153) and other coumarin dyes, and basic coumarin dyes Naphthalimide dyes such as yellow 51, solvent yellow 11 and solvent yellow 116; rhodamine dyes such as rhodamine B, rhodamine 6G, rhodamine 3B, rhodamine 101, rhodamine 110, sulforhodamine, basic violet 11 and basic red 2; 1-ethyl-2- [4- (p-dimethyl) Le-aminophenyl) -1,3-butadienyl] pyridinium - perchlorate (pyridine 1) pyridine dyes such as news, cyanine dyes, or the like oxazine dyes are used.

Furthermore, various dyes (direct dyes, acid dyes, basic dyes, disperse dyes, etc.) can be used as the phosphor of the present invention as long as they have fluorescence.
In the present embodiment, only one kind of inorganic phosphor 7 is used as described above. Therefore, the inorganic phosphor 7 is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits visible light. In the present invention, a plurality of inorganic phosphors 7 may be used. In that case, at least one of the plural types of inorganic phosphors 7 may be an ultraviolet light absorbing phosphor. However, it is of course preferable that all are ultraviolet light absorbing phosphors.
In addition, although two types of phosphors are used for the organic phosphor 8, only one type or three or more types may be used.

  As the transparent substrate 6, for example, a material having a transmittance of 90% or more, more preferably 93% or more with respect to light in a wavelength region of 360 nm or more and 800 nm or less is suitable so that external light can be taken in effectively. . For example, an acrylic substrate such as PMMA resin, a silicon resin substrate, a quartz substrate, or the like is preferably used because it has high transparency to light in a wide wavelength region.

  The first main surface 2a and the second main surface 2b of the light collector 2 are parallel and flat surfaces. Light that travels from the inside of the light collector 2 toward the outside thereof (light emitted from the phosphor) is reflected toward the inside of the light collector 2 at all end surfaces other than the first end surface 2 c of the light collector 2. The reflective layer 5 is provided in direct contact with the end face via an air layer or without the air layer. Further, the light function of light traveling from the inside of the light collector 2 toward the outside thereof (light emitted from the fluorescent material) or the light incident from the first main surface 2a is applied to the second main surface 2b of the light collector 2. A reflection layer (not shown) that reflects the light emitted from the second main surface 2b without being absorbed by the material toward the inside of the light collector 2 is formed on the second main surface 2b via the air layer or the second layer. The main surface 2b is provided in direct contact with no air layer.

  As the reflection layer 5 provided on the end face or the second main surface 2b, a dielectric multilayer such as a reflection layer made of a metal film such as silver or aluminum, an ESR (Enhanced Specular Reflector) reflection film (manufactured by 3M), or the like. A reflective layer made of a film is used. The reflection layer may be a specular reflection layer that specularly reflects incident light or a scattering reflection layer that scatters and reflects incident light. When a scattering reflection layer is used as the reflection layer, the amount of light that goes directly in the direction of the solar cell element 3 increases, so that the light collection efficiency to the solar cell element 3 increases and the amount of power generation increases. In addition, since the reflected light is scattered, changes in the amount of power generation with time and season are averaged. As the scattering reflection layer, microfoamed PET (polyethylene terephthalate) (manufactured by Furukawa Electric) is used.

In the solar cell element 3, the light receiving surface is arranged to face the first end surface 2 c of the light collector 2. The solar cell element 3 is preferably optically bonded to the first end face 2c. As the solar cell element 3, a known solar cell such as a silicon solar cell, a compound solar cell, a quantum dot solar cell, or an organic solar cell can be used. Especially, the compound type solar cell and quantum dot solar cell using a compound semiconductor are suitable as the solar cell element 3 since highly efficient electric power generation is possible. Examples of compound solar cells include InGaP, GaAs, InGaAs, AlGaAs, Cu (In, Ga) Se ₂ , Cu (In, Ga) (Se, S) ₂ , CuInS ₂ , CdTe, CdS, and the like. Examples of the quantum dot solar cell include Si and InGaAs. However, other types of solar cells such as Si and organic can be used depending on the price and application.

  1A shows an example in which the solar cell element 3 is installed only on one end surface 2c of the light collector 2, but the solar cell element 3 may be installed on a plurality of end surfaces of the light collector 2. . When the solar cell element 3 is installed on a part of the end surface (one side, two sides, or three sides) of the light collector 2, the reflective layer 5 may be installed on the end surface where the solar cell element 3 is not installed. preferable.

  The frame 4 is made of a frame such as aluminum, and the first main surface 2a of the light collector 2 is exposed to the outside, and the four sides of the light collector 2 are held in this state, and the solar cell element 3 is also held with the light collector 2. doing. A transparent member such as glass may be fitted into the opening that allows the first main surface 2a of the light collector 2 to face the outside. Under such a configuration, the light collector 2 has a first main surface 2a facing the outside from the frame 4 as a light incident surface, and a first end surface 2c of the light collector 2 as a light exit surface. .

  Among the phosphors used in the present embodiment, the organic phosphor 8 has excellent performance with respect to light collection because it can use light in a wide wavelength range in sunlight as described above. However, the organic phosphor 8 has energy for dissociating bonds between the atoms in the wavelength region of ultraviolet light. For example, the C—C bond, which is a typical interatomic bond, has a wavelength corresponding to its dissociation energy of 340 nm. Similarly, Si—C is 370 nm, C—O is 370 nm, Si—O is 270 nm, C— H is 290 nm. Therefore, by receiving ultraviolet light having a wavelength of less than 380 nm, the organic phosphor 8 breaks the bonds between the atoms and deteriorates so that it does not emit fluorescence. Further, depending on the state of deterioration, there is a risk of condensing light, such as yellowing the transparent substrate 6.

  FIG. 2 is a diagram (graph) showing a sunlight spectrum. As shown in FIG. 2, ultraviolet light having a wavelength of less than 380 nm is included in the sunlight spectrum at a small ratio. Therefore, when this sunlight is received for a long time (long term), light (ultraviolet light) having a wavelength corresponding to the bond dissociation energy between the atoms is irradiated, so that the organic phosphor 8 has bonds between the atoms. Dissociated and deteriorated. In particular, when the organic phosphor 8 has an excitation spectrum peak in the ultraviolet light region, the organic phosphor has high sensitivity to ultraviolet light, and therefore the deterioration is large (fast). In addition, even if it is not the organic fluorescent substance which has the peak of an excitation spectrum in an ultraviolet light range, deterioration will arise by receiving irradiation of ultraviolet light for a long time.

Therefore, in the present invention, the ultraviolet light-absorbing phosphor (inorganic phosphor 7) is used together with the organic phosphor 8, and these are uniformly dispersed in the light collector 2, thereby suppressing the deterioration of the organic phosphor 8. . That is, the ultraviolet light-absorbing phosphor [BaMg ₂ Al ₁₆ O ₂₇ : Eu] used in the present embodiment is excited mainly in the ultraviolet light region as indicated by a broken line in FIG. 3 and in the visible light region as indicated by a solid line. It has an emission peak at a certain wavelength of 515 nm. Therefore, when this ultraviolet light absorbing phosphor (inorganic phosphor 7) absorbs ultraviolet light and emits light, the degree to which the organic phosphor 8 is irradiated with ultraviolet light is reduced, whereby the organic phosphor 8 is exposed to ultraviolet light. Deterioration due to is suppressed.

  In addition, the wavelength range in which the phosphor can efficiently absorb sunlight is approximately 380 nm to 600 nm in a general organic phosphor, whereas the ultraviolet light absorbing phosphor having an excitation spectrum as shown in FIG. By using (inorganic phosphor 7) in combination, it is enlarged to 300 nm to 600 nm. That is, as shown by a two-dot chain line in FIG. 1, since the light is condensed by both the inorganic phosphor 7 and the organic phosphor 8, the light collection efficiency is increased. Compared with the case where only an organic phosphor is used, this can absorb 1.1 times the light by using the ultraviolet light absorbing phosphor (inorganic phosphor 7) in combination.

Therefore, in the solar cell module 1 of the present embodiment, since the organic phosphor 8 and the ultraviolet light absorbing phosphor (inorganic phosphor 7) are used in combination, the ultraviolet light absorbing phosphor emits the ultraviolet light in the incident light. By absorbing and emitting light, the organic phosphor 8 can be prevented from absorbing ultraviolet light, and its deterioration can be suppressed. Therefore, the fall of the condensing function accompanying use of the light-condensing plate 2 can be suppressed, Therefore, the solar cell module 1 which has this light-condensing plate 2 comes to exhibit the light condensing function excellent over the long term.
In addition, the combined use of the organic phosphor 8 and the ultraviolet light-absorbing phosphor (inorganic phosphor 7) has expanded the wavelength range that can be efficiently absorbed in sunlight, thus increasing the light collection efficiency and improving the power generation efficiency. can do.

Further, since the light collector 2 includes the inorganic phosphor 7, the first organic phosphor 8a having an emission peak at a wavelength of 490 nm, and the second organic phosphor 8b having an emission peak at a wavelength of 578 nm, the inorganic fluorescent material is used. The light absorbed by the body 7 is transferred to the first organic phosphor 8a and further transferred from the first organic phosphor 8a to the second organic phosphor 8b, so that the light can be transferred to the solar cell element 3 with higher efficiency. Can lead. For example, the light emitted from the inorganic phosphor 7 is absorbed by the first organic phosphor 8a to cause the first organic phosphor 8a to fluoresce (emit light), and the light emitted from the first organic phosphor 8a is used as the second organic phosphor. The second organic phosphor 8b can be made to fluoresce (emit) by being absorbed by 8b. That is, by applying the energy transfer theory between such phosphors, it is possible to emit only the phosphor having the longest emission peak, thereby increasing the fluorescence quantum yield of the phosphor. be able to.
As the energy transfer, it is possible to emit light with the optical functional material having the largest peak wavelength of the emission spectrum, particularly by the excitation energy moving by the Forster mechanism between the optical functional materials described later.

  In the present embodiment, the light collecting plate 2 (light collecting member) is configured by dispersing the phosphors 7 and 8 in the transparent substrate 6, but the light collecting plate (light collecting member) of the present invention is such as this. Without being limited to the configuration, for example, a configuration as shown in FIG. 4A or FIG. 4B can be used. That is, as shown in FIG. 4 (a), a phosphor layer 9 was formed by applying a coating material in which a phosphor (not shown) was dispersed on the surface of a plate-like transparent substrate 6 made of an acrylic plate or the like. A light collector may be used. Further, as shown in FIG. 4B, a light collector in which a transparent protective layer (transparent layer) 10 is further provided on the surface of the phosphor layer 9 (surface opposite to the transparent substrate 6) may be used. . Here, it is assumed that the phosphor layer 9 includes both the organic phosphor 8 and the ultraviolet light-absorbing phosphor (inorganic phosphor 7) and is uniformly dispersed.

  Various transparent resins can be used as a material for forming the transparent protective layer 10. Specifically, the transparent protective layer 10 can be formed by laminating a transparent resin film made of polyethylene terephthalate (PET), polyethylene (PE), polyvinylidene chloride, polyamide or the like on the phosphor layer 9. Or dissolve cellulose resin such as cellulose acetate, ethyl cellulose, cellulose acetate butyrate, transparent resin such as polyvinyl chloride, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, polycarbonate, polyvinyl butyral, polymethyl methacrylate, polyvinyl formal, polyurethane etc. The transparent protective layer 10 can also be formed by preparing a coating liquid and applying it on the phosphor layer 9 and then drying it.

[Second Embodiment]
FIG. 5 is a sectional side view of a main part of a second embodiment of the solar cell module according to the present invention. The solar cell module shown in FIG. 5 differs from the solar cell module 1 of the first embodiment shown in FIGS. 1A and 1B in that phosphors dispersed in a light collector (light collector). 7 and 8 density distribution.

  That is, in the light collector 2 shown in FIG. 1B, the phosphors 7 and 8 are almost uniformly dispersed. Therefore, in the transparent substrate 6, both the inorganic phosphor 7 and the organic phosphor 8 have a substantially uniform concentration. Is distributed. On the other hand, in the light collector 11 of the present embodiment shown in FIG. 5, the concentration of the ultraviolet light-absorbing phosphor that is the inorganic phosphor 7 is particularly high on the first main surface 2a (light incident surface) side. 2 Lower on the main surface 2b (surface opposite to the light incident surface) side.

  The organic phosphor 8 (8a, 8b) may be uniformly dispersed in the transparent substrate 6, but is opposite to the inorganic phosphor 7 (ultraviolet light absorbing phosphor) as shown in FIG. In addition, it is preferable that the concentration is low on the first main surface 2a (light incident surface) side and the concentration is high on the second main surface 2b (surface opposite to the light incident surface) side.

  Thus, in order to produce the light collector 11 having a concentration distribution (concentration gradient) in at least the inorganic phosphor 7 (ultraviolet light-absorbing phosphor), for example, the inorganic phosphor 7 ( Ultraviolet light absorbing phosphor) is added and settled by its own weight, thereby biasing the inorganic phosphor 7 to one side, and then the side where the inorganic phosphor 7 is biased and has a high concentration becomes the first main surface 2a. Thus, the light collector 2 is molded. When the inorganic phosphor 7 has a polarity, the inorganic phosphor 7 is biased to one side by an electric or magnetic method in the material of the transparent substrate 6 in a molten state, and then the inorganic phosphor 7 The light collector 2 is molded so that the side on which the body 7 is biased and has a high concentration becomes the first main surface 2a.

  In the solar cell module of the present embodiment, the concentration of the ultraviolet light-absorbing phosphor (inorganic phosphor 7) in the light collector 2 is the first main surface that is the incident surface of sunlight compared to the second main surface 2b side. Since the height is increased on the surface 2a side, more ultraviolet light contained in sunlight can be absorbed with high probability on the first main surface 2a side. Therefore, the ultraviolet light irradiated to the organic fluorescent substance 8 can be decreased, and thereby the deterioration of the organic fluorescent substance 8 due to the ultraviolet light can be surely suppressed. Therefore, the fall of the condensing function accompanying use of the light-condensing plate 11 can be suppressed significantly, Therefore, the solar cell module which has this light-condensing plate 11 comes to exhibit the light-condensing function excellent over the long term. .

  In addition, by adapting the energy transfer theory between the phosphors, only the phosphor having the longest emission peak can be caused to emit light, thereby increasing the fluorescence quantum yield of the phosphor.

  Also in this embodiment, as the light collector 11 (light collector), a coating material in which a phosphor (not shown) is dispersed on the surface of the transparent substrate 6 is applied as shown in FIG. In addition, a configuration in which the phosphor layer 9 is formed may be used. Further, as shown in FIG. 4B, a structure in which a transparent protective layer (transparent layer) 10 is further provided on the surface of the phosphor layer 9 (surface opposite to the transparent substrate 6) may be used. Good. However, in the present embodiment, the phosphor layer 9 contains both the organic phosphor 8 and the ultraviolet light absorbing phosphor (inorganic phosphor 7), but at least the ultraviolet light absorbing phosphor (inorganic phosphor 7). ) Is distributed so that the incident surface side of sunlight has a high concentration without being uniformly dispersed.

[Third Embodiment]
FIG. 6A is a perspective view showing a schematic configuration of a third embodiment of the solar cell module according to the present invention, and FIG. 6B is a sectional side view of the main part of FIG. The solar cell module shown in FIGS. 6A and 6B is different from the solar cell module 1 of the first embodiment shown in FIGS. 1A and 1B in that a light collecting plate (light collecting member) is used. In the configuration,

  That is, the light collector 12 (light condensing member) of this embodiment is formed in a two-layer structure (multi-layer structure) as shown in FIGS. 6A and 6B, and is disposed on the light incident side. The first layer 13 and the second layer 14 arranged behind the first layer 13 are configured. Therefore, in this embodiment, the light incident side surface of the first layer 13 is the first main surface, and the surface of the second layer 14 opposite to the first layer 13 is the second main surface. ing.

  The first layer 13 is formed by having (dispersed) only the inorganic phosphor 7 (ultraviolet light absorbing phosphor) in the transparent substrate, and the second layer 14 is formed of the organic phosphor 8 in the transparent substrate. Only (dispersed). The first layer 13 and the second layer 14 are stacked in contact with each other to form a light collector 12.

  One solar cell element 3 is provided on the first end face 12c of the light collector 12 as in the previous embodiment. However, in this embodiment, although not shown, a solar cell element corresponding only to the first layer 13 and a solar cell element corresponding only to the second layer 14 may be provided separately. In this case, the first layer 13 and the second layer 14 have different wavelength ranges of light emitted from the phosphor, and therefore it is preferable to use solar cell elements corresponding to the respective emission wavelength ranges. That is, it is preferable to appropriately select and use a solar cell element with higher power generation efficiency in each emission wavelength region.

  Since the first layer 13 has the inorganic phosphor 7 (ultraviolet light absorbing phosphor) dispersed in the transparent base material, it absorbs light having a wavelength mainly in the ultraviolet region in the incident sunlight and emits light. To do. FIG. 7 is a diagram (graph) showing a solar spectrum after passing through the first layer 13 and thus absorbing ultraviolet light by the inorganic phosphor 7 (ultraviolet light absorbing phosphor) in the first layer 13. is there.

  When FIG. 7 is compared with FIG. 2 showing the sunlight spectrum, the sunlight passing through the first layer 13 as shown in FIG. 7 is removed so that the ultraviolet light side becomes almost zero. Therefore, the light incident on the second layer 14 has almost zero ultraviolet light.

  Therefore, in the light collector 12 according to the present embodiment, the sunlight passes first through the first layer 13 in which only the inorganic phosphor 7 (ultraviolet light absorbing phosphor) is dispersed. It is possible to absorb and remove almost all ultraviolet light from the passing sunlight. Therefore, by making the sunlight from which the ultraviolet light has been removed incident on the second layer 14, it is possible to reliably prevent the deterioration of the organic phosphor 8 in the second layer 14.

As in the first embodiment, when the phosphors 7 and 8 are uniformly dispersed in the light collector 2 so that the concentration of the phosphors 7 and 8 in the light collector 2 is constant, the ultraviolet light is organic. The probability of entering the phosphor 8 is 50% or more. On the other hand, in the present embodiment, the probability that ultraviolet light is incident on the organic phosphor 8 can theoretically be 0%.
Therefore, according to the solar cell module of the present embodiment, it is possible to reliably suppress the deterioration of the organic phosphor 8 due to the ultraviolet light, thereby reliably preventing the light collecting function from being lowered due to the use of the light collector 12. Therefore, the light collecting plate 11 provides an excellent light collecting function for a long time.

  In addition, by adapting the energy transfer theory between the phosphors, only the phosphor having the longest emission peak can be caused to emit light, thereby increasing the fluorescence quantum yield of the phosphor.

  Also in the present embodiment, as the light collector 12 (light collector), as shown in FIGS. 8A to 8C, a coating material in which a phosphor is dispersed on the surface of the transparent substrate 6 is applied, A structure in which the phosphor layer 9 is formed may be used. That is, as shown in FIG. 8A, the second fluorescent layer (second layer) 14a is applied to the surface of the transparent substrate 6 on the light incident side by applying a coating material in which only the organic phosphor is dispersed. The first fluorescent layer (first layer) 13a may be formed by applying a paint in which only the ultraviolet light absorbing phosphor (inorganic phosphor) is dispersed on the surface, that is, on the light incident side.

Further, as shown in FIG. 8B, a transparent protective layer (transparent layer) 10 may be provided on the first fluorescent layer (first layer) 13a shown in FIG.
Further, as shown in FIG. 8C, a coating material in which only an ultraviolet light absorbing phosphor (inorganic phosphor) is dispersed is applied on the surface of the transparent substrate 6 opposite to the light incident side. A first fluorescent layer (first layer) 13a is formed, and a coating material in which only an organic phosphor is dispersed is applied on the surface thereof, that is, on the side opposite to the light incident side, to thereby form a second fluorescent layer (second layer) 14a. May be formed.
Even when such a configuration is adopted, a reflective layer (not shown) is provided on the outermost surface opposite to the light incident side.

  Further, in the present embodiment, as shown in FIG. 6B, the first layer 13 and the second layer 14 are laminated in contact with each other to form the light collector 12, but as a modification, As shown in FIG. 9A, a transparent layer 15 may be interposed between the first layer 13 and the second layer 14. As the transparent layer 15, a material having a refractive index lower than that of the transparent substrate 6 of the second layer 14, for example, air, various transparent resins, optical glass, or the like is used.

When the transparent layer 15 is interposed between the first layer 13 and the second layer 14 as described above, for example, as shown in FIG. 9B, the ends of the first layer 13 and the second layer 14 as the transparent layer 15. In the case where the spacer S is arranged between the parts and thereby the air layer 15a (transparent layer 15) is arranged between the first layer 13 and the second layer 14, the light emitted from the second layer 14 is emitted from the first layer 13. Without being incident on the light, the light is reflected by the air layer 15 a to be guided (propagated) through the second layer 14 and is incident on the solar cell element 3.
Similarly, even when a transparent substrate 15b having a low refractive index is disposed as the transparent layer 15 as shown in FIG. 9C, the light emitted from the second layer 14 is not incident on the first layer 13 and is transparent. The light is reflected by the base material 15 b (transparent layer 15), guided (propagated) through the second layer 14, and incident on the solar cell element 3.

Therefore, the light emitted from the second layer 14 is incident on the first layer 13, is scattered by the inorganic phosphor 7 in the first layer 13, and part of the light is prevented from being emitted outside the light collector 12. be able to.
Therefore, in the modified example of the present embodiment, by providing the transparent layer 15 between the first layer 13 and the second layer 14, it is possible to further improve the light collection efficiency, which is excellent. A condensing function can be exhibited.
Moreover, when each fluorescent substance 7 and 8 is uniformly disperse | distributed in the light-condensing plate 2 so that the density | concentration of each fluorescent substance 7 and 8 in the light-condensing plate 2 may become fixed like 1st Embodiment, ultraviolet light Is incident on the organic phosphor 8 at 50% or more. On the other hand, in this modification, the probability that ultraviolet light is incident on the organic phosphor 8 can be theoretically set to 0%.

  In addition, also in this modification, about a solar cell element, as shown to Fig.10 (a), the solar cell element 3a corresponding only to the 1st layer 13 and the solar cell element 3b corresponding only to the 2nd layer 14 are each shown. It is preferable to separately provide those solar cell elements 3a and 3b that correspond to the emission wavelength regions of the respective layers 13 and 14.

  Also in this modified example, as the light collecting plate 12 (light collecting member), as shown in FIG. 10B, a coating material in which a phosphor is dispersed is applied to the surface of the transparent substrate 6, and the phosphor layer is formed. You may use the thing of the formed structure. That is, as shown in FIG. 10B, a coating material in which only an ultraviolet light absorbing phosphor (inorganic phosphor) is dispersed is applied to the surface of the transparent substrate 6 opposite to the light incident side, and the first fluorescence is applied. A layer (first layer) 13a is formed. Further, the second fluorescent layer (second layer) 14 a is formed by applying a coating material in which only the organic phosphor is dispersed on the light incident side surface of another transparent substrate 6. The first fluorescent layer 13a and the second fluorescent layer 14a are opposed to each other so that the first fluorescent layer 13a is positioned on the light incident side and the second fluorescent layer 14a is positioned behind the first fluorescent layer 13a. The condensing plate 12 may be formed by interposing the transparent layer 15 in the substrate.

  In addition, if the 1st fluorescence layer (1st layer) 13a is located in the light-incidence side, and the 2nd fluorescence layer 14a is located in the back, these 1st fluorescence layer (1st layer) 13a, 2nd fluorescence The layer 14 a may be provided on any surface of the transparent substrate 6. That is, the first fluorescent layer (first layer) 13a may be provided on the light incident side surface with respect to the transparent substrate 6, and the second fluorescent layer (second layer) 14a is transparent. The base 6 may be provided on the surface opposite to the light incident side.

  Moreover, as a condensing member which concerns on the said 3rd Embodiment and its modification, the 1st layer 13 (13a) arrange | positioned at the incident side and the 2nd layer 14 (14a) arrange | positioned back are provided. For example, the light-condensing member (light-condensing plate) according to the present invention can be obtained even when the first layer 13 (13a) has a layer having an organic phosphor on the incident-side surface.

[Fourth Embodiment]
Fig.11 (a) is principal part side sectional drawing of 4th Embodiment of the solar cell module which concerns on this invention. The solar cell module shown in FIG. 11 (a) is different from the solar cell module 1 of the first embodiment shown in FIGS. 1 (a) and 1 (b), and is dispersed in a light collector (light collector). The inorganic phosphor, that is, the ultraviolet light-absorbing phosphor in the present invention is the quantum dot phosphor 16.

Thus, by using the quantum dot phosphor 16 as the ultraviolet light absorbing phosphor (inorganic phosphor), the energy of light absorbed by the quantum dot phosphor 16 is lost to the organic phosphor 8 by the energy transfer of the Forster mechanism. Transition without any change.
That is, although it is said that no Forster energy transfer occurs in an inorganic phosphor that is not quantum size, in this embodiment, the quantum dot phosphor 16 is used as the inorganic phosphor (ultraviolet light absorbing phosphor). Thus, forster energy transfer can occur.

  In general, when a light collecting plate is formed by using a plurality of phosphors having different absorption and emission wavelength peaks, the spectrum of light emitted from the light collecting plate (emission spectrum) includes the peak of each wavelength. In some cases, the peak of the emission spectrum corresponding to a phosphor having a low value disappears. The cause of this is, for example, energy transfer between phosphors by photoluminescence (PL), energy transfer between phosphors by Forster mechanism (fluorescence resonance energy transfer), and the like.

  Energy transfer by photoluminescence occurs when fluorescence emitted from one phosphor is used as excitation energy for another phosphor. Therefore, when using a normal inorganic phosphor as the ultraviolet light absorbing phosphor as shown in the first to third embodiments, as described above, by utilizing the energy transfer by this photoluminescence, By adapting the energy transfer theory between the phosphors, only the phosphor having the longest emission peak can be made to emit light, thereby increasing the fluorescence quantum yield of the phosphor.

  On the other hand, the Forster mechanism is such that excitation energy moves directly between two adjacent phosphors by electron resonance without going through such light emission and absorption processes. Since energy transfer between phosphors by the Förster mechanism is performed without going through light emission and absorption processes, energy loss is small under optimum conditions. Therefore, it contributes to the improvement of the power generation efficiency of the solar cell module. In the present embodiment, the quantum dot phosphor 16 is used as the ultraviolet light absorbing phosphor (inorganic phosphor) in order to efficiently generate power while suppressing energy loss. Then, by matching the peak of the emission spectrum of the quantum dot phosphor 16 (ultraviolet light absorbing phosphor) with the peak of the absorption spectrum of the organic phosphor 8 used in combination, the energy transfer by the Forster mechanism between the phosphors. Has been done.

  Here, the Forster mechanism will be described with reference to FIGS. FIG. 12A is a diagram showing energy transfer by photoluminescence, and FIG. 12B is a diagram showing energy transfer by the Forster mechanism. FIG. 13A is a diagram for explaining a generation mechanism of energy transfer by the Förster mechanism, and FIG. 13B is a diagram showing energy transfer by the Förster mechanism.

As shown in FIG. 12B, in the phosphor of an organic molecule or quantum dot phosphor 16 (inorganic nanoparticle), energy transfer from the molecule A in the excited state to the molecule B in the ground state is performed by the Forster mechanism. May occur. In the phosphor, when the molecule A is excited and undergoes energy transfer to the molecule B, the molecule B emits light. This energy transfer depends on the intermolecular distance, the emission spectrum of molecule A, and the absorption spectrum of molecule B. When the molecule A is a host molecule and the molecule B is a guest molecule, the rate constant k _{H → G} (movement probability) when energy is transferred is as shown in the equation (1)

In equation (1), ν is the frequency, f ′ _H (ν) is the emission spectrum of the host molecule A, ε (ν) is the absorption spectrum of the guest molecule B, N is the Avogadro constant, n is the refractive index, τ ₀ is the fluorescence lifetime of the host molecule A, R is the intermolecular distance, and K ² is the transition dipole moment (2/3 at random).

When the rate constant is large, energy transfer tends to occur between the phosphors. In order to obtain a large rate constant, it is desirable that the following conditions are satisfied.
[1] The overlap between the emission spectrum of the host molecule A and the absorption spectrum of the guest molecule is large.
[2] The extinction coefficient of guest molecule B is large.
[3] The distance between the host molecule A and the guest molecule B is small.

  [1] represents the ease of resonance between two adjacent phosphors. For example, as shown in FIG. 13A, when the peak wavelength of the emission spectrum of the host molecule A is close to the peak wavelength of the absorption spectrum of the guest molecule B, energy transfer due to the Forster mechanism is likely to occur. As shown in FIG. 13B, when the ground state guest molecule B exists in the vicinity of the excited host molecule A, the wave function of the guest molecule A changes due to resonance properties, and the ground state host molecule A and An excited guest molecule B is formed. Thereby, energy transfer occurs between the host molecule A and the guest molecule B, and the guest molecule B emits light.

  In the above [3], the intermolecular distance at which energy transfer by the Forster mechanism occurs is usually about 10 nm. If the conditions are met, energy transfer occurs even when the intermolecular distance is about 20 nm. If the mixing ratio of the quantum dot phosphor 16 and the organic phosphor 8 (first organic phosphor 8a, second organic phosphor 8b) dispersed in the light collector is appropriately set, the distance between the phosphors is shorter than 20 nm. Become. Therefore, energy transfer due to the Forster mechanism is sufficiently generated. Further, as the quantum dot phosphor 16, the first organic phosphor 8a, and the second organic phosphor 8b, those whose emission spectrum and absorption spectrum sufficiently satisfy the condition [1] are used. As a result, energy transfer from the quantum dot phosphor 16 to the first organic phosphor 8a and energy transfer from the first organic phosphor 8a to the second organic phosphor 8b occur, and the quantum dot phosphor 16, the first Cascade type energy transfer occurs in the order of the organic phosphor 8a and the second organic phosphor 8b.

  In the light collector 17 in which such phosphors are dispersed, phosphors having three different emission spectra (quantum dot phosphor 16, first organic phosphor 8a, and second organic phosphor 8b) are mixed and dispersed. Nevertheless, substantially only light emission of the second organic phosphor 8b occurs due to energy transfer by the Forster mechanism. Therefore, by mixing and dispersing the quantum dot phosphor 16, the first organic phosphor 8a, and the second organic phosphor 8b on the light collector 17, light in a predetermined wavelength region is absorbed, and the light emission quantum of the second organic phosphor 8b. Light emission with a peak wavelength higher than the predetermined wavelength region can be generated with efficiency.

  Such an energy transfer phenomenon is a phenomenon peculiar to organic phosphors, and is not supposed to occur in general inorganic phosphors as described above. However, in some inorganic nano-particle phosphors such as the quantum dot phosphor 16 of the present embodiment, energy transfer between inorganic phosphors or between inorganic phosphors and organic phosphors by the Forster mechanism. Can be generated. Examples of the quantum dot phosphor 16 that causes energy transfer between inorganic phosphors or between an inorganic phosphor and an organic phosphor by such a Förster mechanism include the following.

For example, energy transfer occurs between two different sized quantum dots in a ZnO / MgZnO core-shell structure. Since a quantum dot having a dimensional ratio of 1: √2 has a resonating exciton level, for example, 2 having a radius of 3 nm (peak wavelength of emission spectrum: 350 nm) and a radius of 4.5 nm (peak wavelength of emission spectrum: 357 nm). Between types of quantum dots, energy transfer occurs from small to large quantum dots. Energy transfer also occurs between two different sized quantum dots of the CdSe / ZnS core-shell structure. In addition, Mn ²⁺ doped ZnSe quantum dots having a diameter of 8 nm to 9 nm have emission peaks at 450 nm and 580 nm, and are dye molecules 1 ′, 3′-dihydro-1 ′, 3 ′, 3′-trimethyl-6-nitrospiro Quantum dots agree well with the light absorption spectrum of the ring-opened Spiropyran molecule (SPO open; Merocynanine form) obtained by irradiating [2H-1-benzopyran-2,2 '-(2H) -indole] with ultraviolet light Energy transfer from the dye to the dye molecule. In general, an inorganic phosphor is superior in light resistance as compared with an organic phosphor, and thus is advantageous when used for a long period of time.

Normally, when two kinds of phosphors are mixed, as shown in FIG. 12A, the phosphor A first emits light with a certain efficiency, enters the phosphor B, and the phosphor B absorbs and emits light. Through this process, light is emitted from the phosphor B. In such energy transfer by photoluminescence, energy loss occurs in the light emission process in the phosphor A and the light absorption process in the phosphor B, and the energy transfer efficiency is small.
On the other hand, in the energy transfer by the Forster mechanism shown in FIG. 12B, only the energy moves directly between the phosphors, so that the energy transfer efficiency can be almost 100%, and the energy transfer is highly efficient. Movement can occur.

In the solar cell module of the present embodiment, the light collecting plate 17 is formed using the quantum dot phosphor 16 as the ultraviolet light absorbing phosphor (inorganic phosphor), and thus the light absorbed by the quantum dot phosphor 16 Can be transferred to the organic phosphor 8 without loss by energy transfer of the Forster mechanism. That is, by appropriately changing the particle diameter of the quantum dot phosphor 16, the absorption wavelength and emission wavelength can be arbitrarily set, and therefore energy transfer of the Forster mechanism can be easily generated. Therefore, the power generation efficiency can be greatly improved by enabling condensing with high efficiency.
Similarly to the first embodiment, the quantum dot phosphor 16 (ultraviolet light absorbing phosphor) absorbs ultraviolet light in the incident light and emits light, so that deterioration of the organic phosphor 8 can be suppressed. Therefore, it is possible to suppress a decrease in the light collecting function due to the use of the light collecting plate 17.

  In the fourth embodiment, the case where the quantum dot phosphor 16 is used as the ultraviolet light absorbing phosphor in the present invention has been described. However, for example, when a plurality of inorganic phosphors are used, at least one of them is a normal one. An ultraviolet light absorbing phosphor made of an inorganic phosphor may be used, and at least one other kind may be the quantum dot phosphor 16.

  Also in this embodiment, as the light collector 17 (light collector), an inorganic phosphor (not shown) and an organic phosphor (not shown) are provided on the surface of the transparent substrate 6 as shown in FIG. And a coating material in which the phosphor layer 18 is formed may be used. Moreover, you may use the thing of the structure which further provided the transparent protective layer (not shown) in the surface (surface on the opposite side to the transparent base material 6) of the said fluorescent substance layer 18. FIG. However, in the present embodiment, the phosphor layer 18 includes quantum dot phosphors as ultraviolet light absorbing phosphors (inorganic phosphors).

[Fifth Embodiment]
FIG. 14A is a side sectional view of a main part of a fifth embodiment of the solar cell module according to the present invention. The solar cell module shown in FIG. 14A is different from the solar cell module 1 of the first embodiment shown in FIGS. 1A and 1B in that it is dispersed in the light collector 19 (light collector). As the obtained inorganic phosphor 20, that is, the ultraviolet light-absorbing phosphor in the present invention, the one whose emission wavelength peak is longer than the peaks of the organic phosphors 8a and 8b (other phosphors) is used. It is a point.

  That is, in this embodiment, CdSe having a large Stokes shift is used as the inorganic phosphor 20 (ultraviolet light absorbing phosphor). This CdSe (inorganic phosphor 19) has an emission wavelength peak of its emission spectrum in the vicinity of 640 nm as shown by a solid line in FIG. On the other hand, the absorption peak of the absorption spectrum of the first organic phosphor 8a (BASF Lumogen F Yellow 083 (trade name)) and the second organic phosphor 8b (BASF Lumogen F Red 305 (trade name)) The absorption spectrum of the second organic phosphor 8b on the long wavelength side is in the vicinity of 575 nm as shown by the broken line in FIG.

  Therefore, the inorganic phosphor 20 (CdSe) has an emission wavelength peak on the longer wavelength side than the absorption wavelength peak of either the first organic phosphor 8a or the second organic phosphor 8b. By using such an inorganic phosphor 20, most of the light emitted by the inorganic phosphor 20 is not absorbed by the organic phosphors 8 a and 8 b but is guided (propagated) through the light collector 19 as it is. Then, the light enters the solar cell element 3.

  Here, for example, when the peak of the emission wavelength of the inorganic phosphor 7 overlaps with the absorption wavelength region of the organic phosphor 8 as in the first embodiment, as shown in FIG. The light emitted by 7 is absorbed by the organic phosphor 8 to emit light and is guided (propagated). Therefore, when the emission quantum yield of the inorganic phosphor 7 is ηA and the emission quantum yield of the organic phosphor 8 is ηB, the light guided by the inorganic phosphor 7 toward the solar cell element 3 side is emitted. The efficiency is ηA × ηB. Here, since ηA and ηB are both less than 1, ηA × ηB <ηA.

  On the other hand, in this embodiment, the emission wavelength peak of the inorganic phosphor 20 is longer than the absorption wavelength peak of the organic phosphor 8 (8a, 8b), so that the inorganic phosphor 20 is inorganic as shown in FIG. The light emitted from the phosphor 20 is guided (propagated) without being absorbed by the organic phosphor 8. That is, the light emitted from the inorganic phosphor 20 is directly guided (propagated) to the solar cell element 3 side installed on the end face. Therefore, the efficiency of the light guided to the solar cell element 3 side among the light emitted from the inorganic phosphor 20 is not related to the organic phosphor 8, and is ηA. That is, the efficiency (ηA × ηB) of the inorganic phosphor 7 shown in FIG.

Thus, in the solar cell module of the present embodiment, as the inorganic phosphor 20 (ultraviolet light absorbing phosphor), the emission wavelength peak is higher than the peaks of the organic phosphors 8a and 8b (other phosphors). Since the light having the longer wavelength side is also used, the efficiency of the light emitted from the inorganic phosphor 20 to be guided (propagated) to the solar cell element 3 side can be increased. Therefore, the power generation efficiency can be greatly improved.
Further, as in the first embodiment, the ultraviolet light absorbing phosphor (inorganic phosphor 20) absorbs the ultraviolet light in the incident light and emits light, thereby suppressing the deterioration of the organic phosphor 8. Accordingly, it is possible to suppress a decrease in the light collecting function due to the use of the light collector 19.

  Also in this embodiment, as the light collector 19 (light collector), an inorganic phosphor (not shown) and an organic phosphor (see FIG. 14) are formed on the surface of the transparent substrate 6 as shown in FIG. It is also possible to use a structure in which a phosphor layer 21 is formed by applying a paint in which both are dispersed together. Moreover, you may use the thing of the structure which further provided the transparent protective layer (not shown) in the surface (surface on the opposite side to the transparent base material 6) of the said fluorescent substance layer 21. FIG. However, in the present embodiment, the phosphor layer 21 has an ultraviolet light absorbing phosphor (inorganic phosphor) whose emission wavelength peak is longer than the peaks of the organic phosphors 8a and 8b (other phosphors). It is assumed that the inorganic phosphor 20 on the side is used.

  In addition, as in the present embodiment, as an ultraviolet light absorbing phosphor (inorganic phosphor), the emission wavelength peak is longer than the peaks of the organic phosphors 8a and 8b (other phosphors). The point using the body 20 can also be applied to the second embodiment.

[Solar power generator]
FIG. 17 is a schematic configuration diagram of the solar power generation device 1000.
The solar power generation apparatus 1000 includes a solar cell module 1001 that converts sunlight energy into electric power, an inverter (DC / AC converter) 1004 that converts DC power output from the solar cell module 1001 into AC power, A storage battery 1005 that stores DC power output from the battery module 1001.

  The solar cell module 1001 includes a light collecting member (light collecting plate) 1002 that collects sunlight, and a solar cell element 1003 that generates power using the sunlight collected by the light collecting member 1002. As such a solar cell module 1001, the solar cell module demonstrated in 1st Embodiment thru | or 5th Embodiment is used suitably, for example.

The solar power generation device 1000 supplies power to the external electronic device 1006. The electronic device 1006 is supplied with power from the auxiliary power source 1007 as necessary.
Since the solar power generation apparatus 1000 having such a configuration includes the solar cell module according to the present invention described above, the solar power generation apparatus 1000 exhibits an excellent light collecting function for a long period of time and has high power generation efficiency. .

  The present invention can be used for a solar cell module and a solar power generation device.

DESCRIPTION OF SYMBOLS 1 ... Solar cell module, 2 ... Light collecting plate (light collecting member), 3 ... Solar cell element, 6 ... Transparent base material, 7 ... Inorganic fluorescent substance, 8 ... Organic fluorescent substance, 8a ... 1st organic fluorescent substance, 8b ... Second organic phosphor, 9 ... phosphor layer, 10 ... transparent protective layer (transparent layer), 11 ... light collecting plate (light collecting member), 12 ... light collecting plate (light collecting member), 13 ... first layer, 13a ... First fluorescent layer, 14 ... second layer, 14a ... second fluorescent layer, 15 ... transparent layer, 16 ... quantum dot phosphor, 17 ... light collecting plate (light collecting member), 18 ... phosphor layer, 19 ... light collecting plate (Condensing member), 20 ... inorganic phosphor, 21 ... phosphor layer, 1000 ... solar power generation device, L ... light

Claims (10)

A light collecting member that absorbs light incident from the outside by a phosphor, propagates light emitted from the phosphor inside, and emits the light from at least one end surface; and is disposed on the end surface of the light collecting member and A solar cell element that receives light emitted from the end face and generates electric power, and
The solar cell module, wherein the phosphor comprises an organic phosphor and an inorganic phosphor, and at least one of the inorganic phosphors is an ultraviolet light absorbing phosphor that absorbs ultraviolet light and emits light. .   2. The solar cell module according to claim 1, wherein the light collecting member is formed by dispersing the phosphor in a transparent substrate.   The condensing member is characterized in that the concentration of the ultraviolet light absorbing phosphor on the light incident surface side is higher than the concentration of the ultraviolet light absorbing phosphor on the side opposite to the light incident surface side. The solar cell module according to claim 2.   The solar cell module according to claim 1, wherein the condensing member is provided with a phosphor layer in which the phosphor is dispersed on the surface of a transparent substrate.   The solar cell module according to claim 4, wherein the condensing member has a transparent layer provided on a surface of the phosphor layer opposite to the transparent substrate.   The condensing member includes a first layer disposed on the light incident side and a second layer disposed behind the first layer, and the first layer includes the inorganic phosphor. And the said 2nd layer has the said organic fluorescent substance, The solar cell module as described in any one of Claim 1, 2, 4, 5 characterized by the above-mentioned.   The condensing member has a transparent layer between the first layer and the second layer, and the transparent layer has a refractive index lower than a refractive index of the transparent base material of the second layer. The solar cell module according to claim 6.   The solar cell module according to any one of claims 1 to 7, wherein a peak of an emission wavelength of the ultraviolet light absorbing phosphor is on a longer wavelength side than a peak of an absorption wavelength of another phosphor. .   The solar cell module according to claim 1, wherein the inorganic phosphor includes a quantum dot phosphor.   A solar power generation apparatus comprising the solar cell module according to any one of claims 1 to 9.

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