JP2019103362A - Thermophotovoltaic power generator - Google Patents

Abstract

To provide a thermophotovoltaic power generator capable of suppressing deformation and deterioration due to softening of a transmissive plate and capable of maintaining power generation performance for a long time by reducing a transmission amount of light of a wavelength other than a sensitivity region of a photoelectric element.SOLUTION: A power generator 10 is a thermophotovoltaic power generator which includes a photoelectric element 22 and a plurality of transmissive plates 30, and generates power by light of radiation light from a high temperature material heated or melted, the light transmitting through the transmissive plates to enter the photoelectric element. An outside transmissive plate 32 that is a transmissive plate closest to the high temperature material among the plurality of transmissive plates 30 is a transmissive plate having a maximum service temperature of 800°C or above, and one or more inside transmissive plates 34 that are transmissive plates other than the outside transmissive plate 32 among the plurality of transmissive plates 30 include a transmissive plate in which a ratio of a light absorption wavelength region to a wavelength region of 1.8-5.0 μm is 40% or more.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a thermal photovoltaic power generation system.

  DESCRIPTION OF RELATED ART The electric power generation apparatus provided with the photoelectric conversion element which converts light into electric power by the photovoltaic effect, ie, a thermophotovoltaic electric power generation apparatus, is known (for example, refer patent document 1).

U.S. Pat. No. 6,303,853

  By the way, while the sensitivity area | region (for example, wavelength range 0.8-1.8 micrometers) of a photoelectric element is limited, the emitted light of high temperature materials, such as a steel material, has a comparatively wide wavelength range. The radiation having a wavelength longer than that of the sensitivity region causes the photoelectric element to generate heat and raise the temperature but does not contribute to the power generation, but conversely raises the temperature of the photoelectric element and lowers the power generation efficiency.

  Therefore, in order to appropriately absorb light in a wavelength range longer than the sensitivity range, it is conceivable to dispose a transmissive plate that absorbs light of a specific wavelength on the front surface of the photoelectric element. However, a transmissive plate having a light absorption wavelength range in an appropriate region often does not have high heat resistance, and may be softened and deformed by radiant heat, or may deteriorate to deteriorate transparency. As a result, the power generation performance is reduced, the service life is shortened, and it is difficult to form a power generator that can withstand use.

  The present invention relates to a thermal photovoltaic power generation apparatus in which a transmissive plate is disposed on the front surface of a photoelectric device, wherein deformation or deterioration due to softening of the transmissive plate is suppressed, and transmission of wavelengths other than the sensitivity region of the photoelectric device is reduced. An object of the present invention is to provide a thermal photovoltaic power generation apparatus capable of maintaining power generation performance for a long time.

  The gist of the present invention is as follows.

<1>
Photoelectric element,
With multiple permeable plates,
A thermal photovoltaic power generation apparatus that generates electricity by light transmitted through the plurality of transmissive plates of radiant light from a heated or melted high-temperature material and incident on the photoelectric element,
The outer permeable plate which is the permeable plate closest to the high temperature material among the plurality of permeable plates is a permeable plate having a performance at a maximum use temperature of 800 ° C. or higher,
The ratio of the light absorption wavelength range to the wavelength range of 1.8 to 5.0 μm is 40 in one or more inner transmittance plates which are transmittance plates other than the outer transmittance plate among the plurality of transmittance plates. Contains a permeable plate that is more than
Power generator.
The light absorption wavelength range means a wavelength range in which the transmittance is 40% or less.
(effect)
In this aspect, light transmitted through the plurality of transmissive plates among the radiant light from the heated or melted high-temperature material is incident on the photoelectric element, and power is generated by the light.
Here, among the plurality of permeable plates, the outer permeable plate (the permeable plate closest to the high temperature material among the plurality of permeable plates) is a permeable plate having a performance with a maximum use temperature of 800 ° C. or higher, The ratio of the light absorption wavelength range to the wavelength range of 1.8 to 5.0 μm is 40% or more in one or more inner transmittance plates (a transmittance plate other than the outer transmittance plate among the plurality of transmittance plates) A permeable plate is included.
For this reason, while being able to absorb effectively the radiation of a wavelength range (wavelength 1.8-5.0 micrometers) whose wavelength is longer than a sensitivity region (0.8-1.8 micrometers) by a transmission board, It is possible to suppress deformation and deterioration due to softening.
Therefore, according to the power generation device of this aspect, it is possible to suppress deformation or deterioration due to the softening of the permeable plate, and to maintain power generation performance for a long time.
<2>
The outer permeable plate is quartz glass,
The thermal photovoltaic power generation device as described in <1>.
<3>
Between the outer permeable plate and at least one of the inner permeable plates, there is an inversion in transmittance in the wavelength range of 1.8 to 8.0 μm,
The thermal photovoltaic power generation device as described in <1> or <2>.
<4>
The inner permeable plate is plural;
The plurality of inner transparent plates include a first inner transparent plate and a second inner transparent plate, each of which has a light absorption wavelength ratio of 40% or more in a wavelength range of 1.8 to 5.0 μm. ,
Between the first inner transparent plate and the second inner transparent plate, there is an inversion of transmittance in the wavelength range of 1.8 to 5.0 μm,
The thermal photovoltaic power generation device as described in any one of <1>-<3>.
<5>
The inner permeable plate is plural;
The plurality of inner transparent plates include a first inner transparent plate and a second inner transparent plate, each of which has a light absorption wavelength ratio of 40% or more in a wavelength range of 1.8 to 5.0 μm. ,
The first inner permeable plate and the second inner permeable plate satisfy the following relationship:
The thermal photovoltaic power generation device as described in any one of <1>-<3>.

(B−Y) / A and (A−Y) / B are both 0.03 or more

here,
A% of the ratio of the light absorption wavelength region of the first inner transparent plate to the wavelength region 1.8 to 5.0 μm,
B% of the light absorption wavelength range of the second inner transmissive plate in the wavelength range of 1.8 to 5.0 μm,
Y% of the ratio of the wavelength range in which the first inner transmissive plate and the second inner transmissive plate both occupy the light absorption wavelength range occupying the wavelength range of 1.8 to 5.0 μm
I assume.
<6>
The first inner permeable plate and the second inner permeable plate satisfy the following relationship:
The thermal photovoltaic power generation device as described in <5>.

Both (B−Y) / A and (A−Y) / B are at least 0.06

(effect)
It is difficult to prepare a single transmissive plate that absorbs light in the wavelength range of 1.8 to 5.0 μm in a wide range. Therefore, even if one transmissive plate having a light absorption wavelength range of 40% or more in the wavelength range of 1.8 to 5.0 μm is used as the inner side transmissive plate, the wavelength range of 1.8 to 5. It can not widely absorb light in the 0 μm region.
Therefore, in this embodiment, two transmitting plates (a first inner transmitting plate and a second inner transmitting plate, both of which have a ratio of the light absorption wavelength range of 40% or more in the wavelength range of 1.8 to 5.0 μm) Is used as the inner permeable plate, and the two inner permeable plates are made to satisfy the predetermined relationship.
Therefore, the two inner transmissive plates compensate for the high light absorptivity in the wavelength range of 1.8 to 5.0 μm, and the light in the wavelength range of 1.8 to 5.0 μm is in a wide range. Can be absorbed across.
<7>
The average of the transmittances in the wavelength range of 0.8 to 1.8 μm by the plurality of transmissive plates is 50% or more.
The thermal photovoltaic power generation device as described in any one of <1>-<6>.
(effect)
In this aspect, much of the light in the sensitivity region of the photoelectric element is incident on the photoelectric element, so that the power generation efficiency is good.

  According to the present invention, in the thermal photovoltaic power generation apparatus in which the transmissive plate is disposed on the front surface of the photoelectric device, deformation or deterioration due to the softening of the transmissive plate is suppressed, and the transmission amount of wavelengths other than the sensitivity region of the photoelectric device By reducing the power generation performance can be maintained for a long time.

It is a graph which shows the transmittance | permeability of the quartz glass of embodiment. It is a graph which shows the transmittance | permeability of the infrared rays selective glass of embodiment. It is a graph which shows the transmittance | permeability of the optical glass of embodiment. It is a graph which shows the transmittance | permeability of 1st Embodiment (namely, when quartz glass as an outer side permeable board and infrared selective glass is used as an inner side permeable board). It is a graph which shows the transmittance | permeability of 2nd Embodiment (namely, when using quartz glass as an outer side permeable board, and optical glass and infrared selective glass as an inner side permeable board). It is a graph which piles up and shows the transmittance | permeability of quartz glass and infrared selective glass. It is a graph which piles up and shows the transmittance | permeability of optical glass and infrared selective glass. It is a graph which piles up and shows the transmittance | permeability of quartz glass and optical glass. It is a graph which piles up and shows the transmittance | permeability of quartz glass, infrared selective glass, and optical glass. It is a schematic diagram which shows the electric power generating apparatus of 1st Embodiment. It is a schematic diagram which shows the electric power generating apparatus of 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described.

As an embodiment of the present invention, an example will be described in which it is assumed that power generation is performed using radiant light of a high temperature material in a steel mill provided with a production facility for producing a steel material.
That is, in a steelworks, molten high temperature materials such as molten iron and molten steel flow on the crucible, or heated high temperature materials such as slabs and steel plates are conveyed on the table roll. In the present embodiment, power generation is performed by the thermal photovoltaic power generation system 10 (hereinafter simply referred to as the “power generation system 10”) by utilizing the radiation from the high temperature material on the transport path 80 such as the crucible or table roll. Do.

-Thermal photovoltaic power generation system 10-
The power generation device 10 includes a power generation unit 20, a permeable plate 30, and a side surface protection portion 40 as a basic configuration, as shown in FIG. 10 and FIG.

<Power generation unit 20>
The power generation unit 20 is configured to include a photoelectric element 22 (photoelectric conversion cell, PV cell) that converts light into electric power by the photovoltaic effect. As the photoelectric device 22, GaSb-based, InGaSa-based, InGaAsBb-based ones, etc. are used, and in particular, GaSb-based ones are suitably used. The GsSb-based photoelectric element has a high sensitivity region at a wavelength of 0.8 to 1.8 μm, and efficiently emits an electromotive force when near infrared light having a wavelength of 0.8 to 1.8 μm is incident. Produce (thermal photovoltaic power generation). A plurality of photoelectric elements 22 are provided.

<Permeable plate 30>
The permeable plate 30 is provided on the high temperature material 90 side of the power generation device 10 (that is, on the front surface side of the power generation device 10). Therefore, the radiant light of the high temperature material 90 is transmitted through the transmissive plate 30 and then enters the photoelectric element 22.

A plurality of permeable plates 30 are provided. The transmissive plate 30 is provided to form a space 12 with the photoelectric element 22. When the transparent plate 30 is in contact with the photoelectric element 22, when the transparent plate 30 is heated and the temperature rises, the heat is directly transmitted to the photoelectric element 22, and the temperature of the photoelectric element 22 rises excessively, and the power generation efficiency is improved. It is to go down.
However, when the space 12 is formed between the transmissive plates 30, one of the plurality of transmissive plates 30 may be brought close to or in contact with the photoelectric element 22. The detailed configuration of the plurality of permeable plates 30 will be described later.

<Side protection unit 40>
The side surface protection unit 40 is provided in the space 12 formed by the permeable plate 30 (including not only the space between the permeable plate 30 and the photoelectric element 22 but also the space between the plurality of permeable plates 30). Prevent the mixture of flying objects. As the scattered matter referred to here, dust such as iron powder scattering in the steel mill, moisture, etc. are assumed.

The side surface protection unit 40 is provided on the side of the space 12 formed by the permeable plate 30 and isolates the space 12 described above from the outside of the power generation device 10. The side surface protection unit 40 is configured to inhibit passage of the scattered matter.
On the other hand, the side surface protection unit 40 may be configured to block the passage of air as well as the scattered matter, but is preferably configured to allow the passage of air. When the side surface protection unit 40 allows the air to pass, the air flow is likely to occur in the space 12 and the temperature rise in the space 12 is suppressed. When the temperature rise of the space 12 is suppressed, the power generation efficiency decrease due to the temperature rise of the photoelectric element 22 is suppressed.

The specific structure of the side protection part 40 which allows passage of air, inhibiting the passage of a scattering thing is a structure as follows, for example.
That is, a filter or a mesh is formed on a part or the whole of the side surface protection unit 40. In order to improve the passage of air, it is preferable that a filter or a mesh be formed on two or more of the four side protection parts. If the material is an air filter, it is relatively inexpensive and can be replaced before the end of the life to reduce clogging. An incombustible filter of glass fiber etc. are illustrated. In addition, if the material is metal, ceramic, or a composite thereof, it is advantageous that the heat resistance is improved. Examples thereof include high temperature filters obtained by sintering stainless steel mesh, metal powder or metal fibers. By making the filter and the mesh detachable from the side face protection unit 40, they can be used after being replaced or cleaned. As a result, clogging, contamination and the like due to the scattered matter at the time of use can be improved, and the air permeability and the cooling action can be maintained in a good state for a long time.

In addition, the power generation device 10 may include a cooling unit that cools the photoelectric element. As the cooling unit, for example, there is an air cooling mechanism (not shown) in which the power generation device 10 forcibly generates the flow of air in the space 12. By creating a flow of air in the space 12 by the air cooling mechanism, the temperature rise of the space 12 is suppressed, and the decrease in the power generation efficiency due to the temperature rise of the photoelectric element 22 is suppressed.
Specifically, the temperature rise of the photoelectric element 22 is suppressed by the flow of air generated by the air cooling mechanism. In addition, cooling of the transmissive plate 30 suppresses the emission of light in the unnecessary wavelength range absorbed by the transmissive plate 30 from the transmissive plate 30 again, which also causes the photoelectric element 22 to The temperature rise can be suppressed.
Further, the cooling unit is not limited to the air cooling mechanism, and may be a water cooling mechanism having a higher cooling capability (a water cooling mechanism 26 described later as an example).

  The power generation unit 20 may be configured to include the heat dissipation substrate 24 as shown in FIG. By mounting the photoelectric conversion element 22 on one side of the heat dissipation substrate 24, the temperature rise of the photoelectric conversion element 22 is suppressed, and the decrease in the power generation effect due to the temperature increase is suppressed. As the heat dissipation substrate 24, one in which Cu is laminated on one side or both sides of a ceramic substrate is mentioned as an example.

  Furthermore, the power generation unit 20 may be configured to include a water cooling mechanism 26. The water cooling mechanism 26 is provided on the surface of the heat dissipation substrate 24 opposite to the surface on which the photoelectric element 22 is mounted. As the water cooling mechanism 26, for example, a water cooled copper plate is used.

[Multiple permeable plates]
Next, the detailed configuration of the plurality of permeable plates 30 will be described.

  Typical types of the transmissive plate 30 include quartz glass, optical glass, and infrared selective glass.

  Quartz glass has high heat resistance, the maximum service temperature of which exceeds 1000 ° C. The composition of quartz glass is approximately 100% silicon dioxide. If the quartz glass is further classified, it can be divided into fused silica glass, oxyhydrocarbon glass, synthetic quartz glass, etc. from the difference in the production method.

  An example of the optical glass is silica borate glass. This is constituted by adding boron oxide etc. while having silicon dioxide as a main component. Compared with general soda glass, it is characterized in that it has high light transmittance and less optical distortion.

  The infrared selective glass has, for example, a structure in which dielectric films are laminated in multiple layers on the surface of glass. Although many materials can be used as the dielectric film, typical ones are silicon oxide, titanium oxide and the like. The thickness can be adjusted in the range of 1 to 50 nm. The number of layers can be used by laminating two to about 100 layers. The higher the number of layers, the higher the cost, but the easier the wavelength control. For the glass of the base material, quartz glass, optical glass or the like can be used. That is, as an example of infrared selective glass used for thermal photovoltaic power generation, it is exemplified by optical glass in which silicon oxide and titanium oxide are alternately stacked to form a film configured to have a total of about 20 layers.

  An example of the transmittance of quartz glass, optical glass and infrared selective glass is shown in FIGS. 1, 2 and 3 respectively. As shown in these figures, the wavelength range in which the light absorption rate is high differs depending on the type of the transmissive plate. Higher effects can often be obtained in the range above about 5 μm for quartz glass, over 2.5 μm for optical glass, and over 1.5 μm for infrared selective glass.

The quartz glass shown in FIG. 1 has a thickness of 1 mm, and high heat resistance, for example, those having a maximum use temperature of 1000 ° C. or more or 1200 ° C. or more can be used.
The infrared selective glass shown in FIG. 2 has a thickness of 1 mm. The heat resistance of the infrared selective glass is inferior to that of quartz glass, and for example, those having a maximum use temperature of 150 ° C. or higher or 200 ° C. or higher can be used.
The optical glass shown in FIG. 3 has a thickness of 1 mm. The heat resistance of the optical glass may be, for example, one having a maximum use temperature of 500 ° C. or more or 600 ° C. or more.

  With regard to the order of arrangement of the permeable plates, the life of the other permeable plates can be enhanced by arranging quartz glass with high heat resistance near the high temperature material. In particular, when the heat resistance of the optical glass to be used and the infrared selective glass is relatively low, it is effective to dispose the quartz glass on the high temperature material side. When simultaneously using an optical glass and an infrared selective glass, it is effective to arrange the optical glass and the infrared selective glass in order from the heat source side to suppress the deterioration of the coating of the infrared selective glass. Therefore, when three or more types of transmissive plates are used simultaneously, higher heat resistance and improved power generation efficiency can be expected by arranging quartz glass, optical glass and infrared selective glass in this order from the heat source side.

  By arranging the plurality of permeable plates apart from each other, the cooling performance of each permeable plate can be enhanced. As a result, it is possible to control the emitted light to increase the power generation efficiency, or to suppress the deformation of the transmissive plate at a high temperature to improve the life. The distance between the permeable plates is preferably in the range of 0.3 to 30 mm. Within this range, it is advantageous to increase the power generation efficiency and prolong the life of the plate. If the distance between the plates is less than 0.3 mm, the influence of heat dissipation of the plates on the adjacent plates becomes large, and there is a concern that the cooling ability of the plates may be reduced. If it is more than 30 mm, more of the light transmitted through the transmission plate will be displaced due to refraction, making it difficult to control the radiation reaching the photoelectric element, or the distance from the high temperature material to the power generation unit will be longer. It becomes a problem that it falls. It is also possible to save space by contacting a part of the permeable plate.

[Specific embodiment]
Next, the first embodiment and the second embodiment will be described as specific examples of the power generation device of the present invention, that is, specific examples of the combination of the permeable plates.

First Embodiment
In the power generation device 10 according to the first embodiment, the plurality of transmissive plates 30 are formed of two transmissive plates of quartz glass and infrared selective glass arranged in order from the heat source side.

  FIG. 6 shows a graph showing the transmittance of quartz glass and the transmittance of infrared selective glass in an overlapping manner. The measurement result of the transmittance | permeability when using two glass of quartz glass and infrared selective glass in FIG. 4, ie, the graph of the transmittance | permeability by several (two sheets) permeable plate, is shown.

<Function effect>
The effects of the present embodiment will be described.

Quartz glass has high heat resistance. However, as shown in FIG. 1, in quartz glass, most of the light is transmitted in the wavelength range of 1.8 to 5.0 μm. Therefore, when the quartz glass is used alone, the temperature of the photoelectric element 22 may rise, and the power generation performance (efficiency) may be reduced or a failure may occur.
On the other hand, as shown in FIG. 2, the infrared selective glass can reduce the transmitted light in the wavelength range of 1.8 to 5.0 μm. However, since the infrared selective glass has low heat resistance, it needs to be used away from the heat source, and as a result, the power generation performance (efficiency) is reduced.

  So, in this embodiment, the permeable board 30 is made into multiple sheets (two sheets), and the permeable board ("outside permeable board 32") of the side nearest to a heat source is used as quartz glass with high heat resistance. Thereby, even if the permeable plate inferior in heat resistance is arranged as a permeable plate ("inner permeable plate 34") inside the quartz glass among the plurality of permeable plates, the permeable plate inferior in heat resistance Can be suppressed from being softened, deformed or degraded. As a result, it becomes easy to arrange | position the permeable board which has a desired absorption characteristic as an inner side permeable board.

Further, in the present embodiment, as shown in FIG. 2, the infrared selective glass which is the inner transmissive plate 34 has a light absorption wavelength range (a transmittance of 40% or less in a wavelength range of 1.8 to 5.0 μm) , The region of arrow A in FIG. In particular, in the infrared selective glass, the ratio A of the light absorption wavelength range to the wavelength range of 1.8 to 5.0 μm is about 60%.
For this reason, it is possible to effectively absorb the light which is easily transmitted by the quartz glass which is the outer side transparent plate 32 by the infrared selective glass which is the inner side transparent plate 34.

Further, in the present embodiment, as shown in FIG. 6, transmission is performed in a wavelength range of 1.8 to 8.0 μm between the quartz glass as the outer transmitting plate 32 and the infrared selective glass as the inner transmitting plate 34. There is a reversal in rates. For this reason, in the wavelength range of 1.8 to 8.0 μm, the regions having a high light absorption rate are mutually compensated, and light in unnecessary wavelength ranges other than the sensitivity range of the photoelectric element can be effectively absorbed.
Specifically, as shown in FIG. 1, quartz glass, which is the outer transmissive plate 32, has a small transmittance of less than 5% for wavelengths exceeding 5 μm, but transmission in the wavelength range of 1.8 to 4.0 μm The rate is as large as 40% or more. Therefore, by using an infrared selective glass having an area with a small transmittance in the wavelength range of 1.8 to 4.0 μm as the inner side transmissive plate 34 and combining it with the outer side transmissive plate 32, a wavelength range of 1.8 to 8.0 μm The area where the transmittance at the lower side is smaller can be expanded than in the case of the outer permeable plate 32 alone.

  Further, in the present embodiment, as shown in FIG. 4, the transmittance of light in the sensitivity region (wavelength region 0.8 to 1.8 μm in the case of GaSb-based) of the photoelectric element 22 by the plurality of transmissive plates 30. The average is about 80%. For this reason, most of the light in the sensitivity region of the photoelectric element 22 is incident on the photoelectric element 22, so that the power generation efficiency is good.

Second Embodiment
In the first embodiment, an optical glass may be further disposed between quartz glass and infrared selective glass (second embodiment). That is, in the second embodiment, the plurality of transmissive plates 30 are configured of three transmissive plates 30 of quartz glass arranged from the heat source side, optical glass, and infrared selective glass.

  FIG. 9 is a graph showing the respective transmittances of quartz glass, optical glass, and infrared selective glass in an overlapping manner. FIG. 7 shows a graph showing the respective transmittances of the optical glass and the infrared selective glass in an overlapping manner. FIG. 5 shows the measurement results of transmittance when using three sheets of quartz glass, optical glass and infrared selective glass.

<Function effect>
The effects of the present embodiment will be described.
However, description of the effect based on the same structure as 1st Embodiment is abbreviate | omitted suitably.

  In the present embodiment, quartz glass, optical glass and infrared selective glass are arranged in this order from the heat source side. That is, since the plurality of permeable plates 30 are arranged in the order of high heat resistance from the heat source side, the life of the plurality of permeable plates 30 can be effectively enhanced.

  By the way, it is difficult to prepare one transmitting plate which absorbs light of a wavelength range of 1.8 to 5.0 μm in a wide range. Therefore, even if one transmissive plate having a light absorption wavelength range of 40% or more in the wavelength range of 1.8 to 5.0 μm is used as the inner side transmissive plate, the wavelength range of 1.8 to 5. It can not widely absorb light in the 0 μm region.

Therefore, in the present embodiment, the ratio of the light absorption wavelength range to the wavelength range of 1.8 to 5.0 μm is a plurality (two) of the inner transmissive plate 34, and the plurality of inner transmissive plates together The infrared selective glass (see FIG. 2) as the “first inner transparent plate 34A” having an L of 40% or more (see FIG. 2) and the optical glass as the “second inner transparent plate 34B” (see FIG. 3) are included. And as shown in FIG. 7, between the infrared selective glass which is the 1st inner side permeable board 34A, and the optical glass which is the 2nd inner side permeable board 34B, it transmits in a wavelength range of 1.8-5.0 micrometers. There is a rate reversal.
For this reason, it becomes a relationship which compensates the area | region where light absorption rate of each other is high in wavelength-range 1.8-5.0 micrometers. Therefore, compared with the aspect in which the ratio of the light absorption wavelength range occupying the wavelength range of 1.8 to 5.0 μm is 40% or more, the wavelength range of 1.8 to 5.0 μm Light can be absorbed effectively.

Furthermore, in the present embodiment, the two inner permeable plates (the first inner permeable plate 34A and the second inner permeable plate 34B) are made to satisfy the following predetermined relationship.

(B−Y) / A and (A−Y) / B are both about 0.07 or more

here,
A% of the ratio of the light absorption wavelength range of the first inner transparent plate 34A to the wavelength range of 1.8 to 5.0 μm,
The percentage of the light absorption wavelength range of the second inner transmissive plate 34B in the wavelength range of 1.8 to 5.0 μm is B%,
Y% of the ratio of the wavelength range in which both the first inner transmissive plate 34A and the second inner transmissive plate 34B are light absorbing wavelength ranges occupying the wavelength range of 1.8 to 5.0 μm
I assume.

The meaning of the above relationship will be described.
In the present embodiment, the ratio A of the light absorption wavelength range of the first inner transmissive plate 34A to the wavelength range of 1.8 to 5.0 μm is about 60%, and occupies the wavelength range of 1.8 to 5.0 μm. The ratio B of the light absorption wavelength range of the second inner transparent plate 34B is about 70%.
In addition, the ratio Y of the wavelength range in which both the first inner transmissive plate 34A and the second inner transmissive plate 34B are light absorbing wavelength ranges occupying the wavelength range of 1.8 to 5.0 μm is about 55%. .
Thus, (B-Y) / A is about 0.25 and (A-Y) / B is about 0.07.
(B−Y) / A is a ratio of the expanded ratio (B−Y)% to the ratio A% of the first inner permeable plate 34A alone.
Further, (A−Y) / B is a ratio of an expanded ratio (A−Y)% to a ratio B% of only the second inner permeable plate 34B.
That is, when both (B−Y) / A and (A−Y) / B are about 0.07 or more, the case where only the first inner permeable plate 34A is used or the second inner permeable plate 34B is used. It can be said that the light absorption wavelength range is effectively expanded as compared with the case of using only.
Therefore, it does not contribute to the power generation efficiency, but the temperature of the photoelectric device can be raised to cause a decrease in the power generation efficiency, and radiation with a wavelength of 1.8 to 5.0 μm other than the sensitivity region of the photoelectric device can be efficiently absorbed. Thus, a power generation device with excellent power generation efficiency can be obtained.
For this reason, the two inner transmissive plates are in a relationship in which the wavelength region of 1.8 to 5.0 μm effectively compensates for the region having a high light absorptivity. As a result, light of a wavelength range of 1.8 to 5.0 μm can be absorbed over a wide range.

The relationship between the two inner permeable plates 34A and 34B is not limited to the above.
For example,
Both (B−Y) / A and (A−Y) / B may be 0.03 or more.
Preferably,
Both (B−Y) / A and (A−Y) / B are 0.06 or more.

  Further, in the present embodiment, the average of the light transmittance of the sensitivity region (wavelength 0.8 to 1.8 μm in the case of GaSb-based) of the plurality of transmissive plates 30 is about 80%. (See Figure 5). For this reason, most of the light in the sensitivity region of the photoelectric element 22 is incident on the photoelectric element 22, so that the power generation efficiency is good.

[Supplementary explanation]
In addition, although the example using quartz glass as the outer side permeable board 32 was demonstrated in the said embodiment, this invention is not limited to this, You may use glass other than quartz glass as an outer side permeable board.

  Moreover, although the electric power generating apparatus provided with two permeable plates as 1st Embodiment and 3 permeable plates as 2nd Embodiment was demonstrated, this invention is not limited to this. A plurality of permeable plates of each type may be used, and four or more permeable plates may be provided. For example, by using two or more quartz glass and optical glass, it is possible to suppress the temperature rise of each transmissive plate. Specifically, two pieces of quartz glass and two pieces of infrared selective glass are exemplified, and the effect of suppressing the temperature rise of the photoelectric element is enhanced, and as a result, the power generation amount can be increased. Moreover, adjustment of the light quantity to permeate | transmit is possible by adjusting the thickness of a permeable board.

  Alternatively, the plurality of transmissive plates 30 may be configured of two transmissive plates 30 of quartz glass disposed from the heat source side and optical glass. FIG. 8 shows a graph showing the transmittances of quartz glass and optical glass in an overlapping manner.

DESCRIPTION OF SYMBOLS 10 Thermophotovoltaic power generation device 22 Photoelectric element 30 Permeable plate 32 Outer side permeable plate 34 Inner side permeable plate 34A 1st inner side permeable plate 34B 2nd inner side permeable plate 90 High temperature material

Claims (7)

Photoelectric element,
With multiple permeable plates,
A thermal photovoltaic power generation apparatus that generates electricity by light transmitted through the plurality of transmissive plates of radiant light from a heated or melted high-temperature material and incident on the photoelectric element,
The outer permeable plate which is the permeable plate closest to the high temperature material among the plurality of permeable plates is a permeable plate having a performance at a maximum use temperature of 800 ° C. or higher,
The ratio of the light absorption wavelength range to the wavelength range of 1.8 to 5.0 μm is 40 in one or more inner transmittance plates which are transmittance plates other than the outer transmittance plate among the plurality of transmittance plates. Contains a permeable plate that is more than
Power generator. The outer permeable plate is quartz glass,
The thermal photovoltaic power generation device according to claim 1. Between the outer permeable plate and at least one of the inner permeable plates, there is an inversion in transmittance in the wavelength range of 1.8 to 8.0 μm,
The thermal photovoltaic power generation device according to claim 1 or 2. The inner permeable plate is plural;
The plurality of inner transparent plates include a first inner transparent plate and a second inner transparent plate, each of which has a light absorption wavelength ratio of 40% or more in a wavelength range of 1.8 to 5.0 μm. ,
Between the first inner transparent plate and the second inner transparent plate, there is an inversion of transmittance in the wavelength range of 1.8 to 5.0 μm,
The thermal photovoltaic power generation device according to any one of claims 1 to 3. The inner permeable plate is plural;
The plurality of inner transparent plates include a first inner transparent plate and a second inner transparent plate, each of which has a light absorption wavelength ratio of 40% or more in a wavelength range of 1.8 to 5.0 μm. ,
The first inner permeable plate and the second inner permeable plate satisfy the following relationship:
The thermal photovoltaic power generation device according to any one of claims 1 to 3.

(B−Y) / A and (A−Y) / B are both 0.03 or more

here,
A% of the ratio of the light absorption wavelength region of the first inner transparent plate to the wavelength region 1.8 to 5.0 μm,
B% of the light absorption wavelength range of the second inner transmissive plate in the wavelength range of 1.8 to 5.0 μm,
Y% of the ratio of the wavelength range in which the first inner transmissive plate and the second inner transmissive plate both occupy the light absorption wavelength range occupying the wavelength range of 1.8 to 5.0 μm
I assume. The first inner permeable plate and the second inner permeable plate satisfy the following relationship:
The thermal photovoltaic power generation device according to claim 5.

Both (B−Y) / A and (A−Y) / B are at least 0.06
The average of the transmittances in the wavelength range of 0.8 to 1.8 μm by the plurality of transmissive plates is 50% or more.
The thermal photovoltaic power generation device according to any one of claims 1 to 6.