JP6706815B2 - Thermophotovoltaic generator and thermophotovoltaic system - Google Patents

Description

The present invention is directed to a flat plate-shaped radiating unit having a thermal radiant light source that converts heat into radiant light, a heat supply unit that supplies heat supplied from a heat source to the radiant unit, and a photoelectric generator that receives radiant light and generates electricity. The present invention relates to a thermophotovoltaic power generation device including a plate-shaped photoelectric conversion unit including a conversion element.

In general, when an object is heated, light having a spectrum depending on the substance forming the object and the temperature of the object, that is, radiant light is generated. A device that captures this radiant light with a photovoltaic cell to generate electricity is called a thermophotovoltaic (TPV) device (Patent Document 1).

This thermophotovoltaic power generator includes a thermal radiation light source that emits (radiates) radiant light that contains more specific wavelengths, a heat supply unit that supplies heat from the heat source to the thermal radiation light source, and a photoelectric conversion element. And a photoelectric conversion unit.
The thermal radiation light source is configured such that one of the substrates made of, for example, a plate-shaped metal material has a heat absorbing surface and the other has a radiation surface.
The heat supply unit is arranged in contact with and in contact with the heat absorption surface of the heat radiation light source. The photoelectric conversion unit is arranged on the side opposite to the heat supply unit with the thermal radiation light source sandwiched between the photoelectric conversion unit and the radiation surface. That is, the photoelectric conversion unit is arranged to face the heat supply unit.

JP, 2014-217110, A

In the above-mentioned thermophotovoltaic power generation device, since the heat supply unit and the heat absorption surface of the heat radiation light source are arranged in contact with each other, the area of the heat radiation light source cannot be arbitrarily increased. Further, depending on the type of heat radiation light source (for example, in the case of a light transmissive material), radiation light of a wavelength that cannot be converted by the photoelectric conversion element of the photoelectric conversion unit leaks from the heat supply unit, and power generation in the photoelectric conversion unit occurs. It is a loss without contributing. Then, in this case, the photoelectric conversion unit is heated by radiant light having a wavelength that cannot be converted by the photoelectric conversion element of the photoelectric conversion unit, and the power generation efficiency is further reduced.
Therefore, a thermophotovoltaic power generation device having high power generation efficiency without lowering power generation efficiency is desired.

The present invention has been made in view of such circumstances, and an object thereof is to provide a thermophotovoltaic power generation device having high power generation efficiency.

The characteristic configuration of the thermophotovoltaic power generation device according to the present invention for achieving the above object,
A planar radiation portion having a thermal radiation source that converts heat into radiant light to the plane of the flat plate portion, and receives a heat supply portion for supplying the supplied heat to the radiant section from the heat source, the radiant light a flat photoelectric conversion unit provided in the flat portion of the photoelectric conversion element that generates electric power, the thermal photovoltaic device provided with,
The radiating unit is erected on the heat supplying unit so as to be able to conduct heat from the heat supplying unit,
The photoelectric conversion unit is provided at the side of the radiation unit with the photoelectric conversion element facing the thermal radiation light source.

Normally, the surface of the heat supply portion also functions as a radiation surface depending on the material and temperature, and emits radiant light that is not controlled by a specific wavelength distribution. Uncontrolled radiant light from the heat supply section may pass through the radiant section even when the radiant section covers the heat supply section. For example, when the radiating section includes an infrared transparent material such as an infrared transparent substrate such as infrared transparent glass, uncontrolled radiant light from the heat supply section easily passes through the radiating section.
When the heat supply unit emits radiant light as a surface light source, for example, the radiant light from the heat supply unit is incident at a right angle on the surface provided in parallel with the radiating surface of the heat supply unit. Radiation light from the heat supply unit is radiated.
However, according to the above configuration, the photoelectric conversion unit is provided side by side in a state of facing the radiation unit erected in the heat supply unit, so that the arrangement in parallel with the surface of the heat supply unit can be avoided. The radiant light from the heat supply unit does not enter at a right angle. In particular, when the radiation unit is vertically provided in the heat supply unit and the photoelectric conversion unit and the radiation light from the heat supply unit are parallel to each other, the radiation light can be prevented from entering the photoelectric conversion unit. ..
Therefore, the density of the radiated light from the heat supply unit received by the photoelectric conversion unit can be reduced, and heat generation of the photoelectric conversion element can be avoided.

Further, by arranging the radiating portion so as to be able to conduct heat to the heat supplying portion, more radiation portions are provided on the surface of the heat supplying portion than when the radiating portion is covered on the surface of the heat supplying portion. Therefore, of the heat energy of the heat supplied from the heat source to the heat supply unit, more energy is converted into radiant light controlled by the radiating unit, and radiant light that is relatively uncontrolled from the heat supplying unit. The energy that is converted into can be reduced.

Therefore, according to the above configuration, the heat generation of the photoelectric conversion element is avoided, the reduction of the conversion efficiency of the photoelectric conversion element is avoided, and further, a larger proportion of the thermal energy is converted into the controlled radiant light and photoelectric conversion is performed. Since the light can be incident on the photoelectric conversion element of the conversion unit, it is possible to provide a thermophotovoltaic power generation device having high power generation efficiency.

FEATURES configuration of the heat beam generator according to the present invention for achieving the above object,
A flat plate-shaped radiating section provided with a thermal radiation light source for converting heat into radiant light, a heat supply section for supplying the heat supplied from a heat source to the radiating section, and receiving the radiant light. In a photoelectric conversion device having a flat plate-shaped photoelectric conversion unit having a photoelectric conversion element for generating power in a flat section,
The radiating unit is erected on the heat supplying unit so as to be able to conduct heat from the heat supplying unit,
The photoelectric conversion unit is provided side by side with the radiation unit in a state where the photoelectric conversion element is opposed to the thermal radiation light source,
The photoelectric conversion unit is provided side by side with the radiation unit while being supported by a support unit different from the heat supply unit, and further includes a heat absorption unit that cools the photoelectric conversion element.

According to the above configuration, since the photoelectric conversion unit is provided side by side in a state of facing the radiation unit erected in the heat supply unit, it is possible to avoid the arrangement parallel to the surface of the heat supply unit. The radiant light from the supply unit never enters at a right angle. In particular, when the radiation unit is vertically provided in the heat supply unit and the photoelectric conversion unit and the radiation light from the heat supply unit are parallel to each other, the radiation light can be prevented from entering the photoelectric conversion unit. ..
Therefore, the density of the radiated light from the heat supply unit received by the photoelectric conversion unit can be reduced, and heat generation of the photoelectric conversion element can be avoided.
Further, by arranging the radiating portion so as to be able to conduct heat to the heat supplying portion, more radiation portions are provided on the surface of the heat supplying portion than when the radiating portion is covered on the surface of the heat supplying portion. Therefore, of the heat energy of the heat supplied from the heat source to the heat supply unit, more energy is converted into radiant light controlled by the radiating unit, and radiant light that is relatively uncontrolled from the heat supplying unit. The energy that is converted into can be reduced.
Therefore, according to the above configuration, the heat generation of the photoelectric conversion element is avoided, the reduction of the conversion efficiency of the photoelectric conversion element is avoided, and further, a larger proportion of the thermal energy is converted into the controlled radiant light and photoelectric conversion is performed. Since the light can be incident on the photoelectric conversion element of the conversion unit, it is possible to provide a thermophotovoltaic power generation device having high power generation efficiency.

Further, according to the above configuration, the photoelectric conversion unit is not heated by the heat conduction from the heat supply unit. Then, since the photoelectric conversion element is cooled by the heat absorbing portion, it is possible to avoid a decrease in power generation efficiency and provide a thermophotovoltaic power generation device having high power generation efficiency.
When the photoelectric conversion element receives light having a wavelength shorter than the bandgap energy of the photoelectric conversion element, the photoelectric conversion element generates heat due to relaxation within the band.
However, since the photoelectric conversion element is cooled by the heat absorption section, it is possible to generate electricity in the state where the photoelectric conversion section is maintained at a temperature with high power generation efficiency. Therefore, it is possible to avoid a decrease in power generation efficiency and provide a thermophotovoltaic power generator with high power generation efficiency.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The heat absorbing portion is formed in a flat plate shape, the photoelectric conversion element is provided on a flat surface portion of the heat absorbing portion, and the photoelectric conversion element is connected to the flat surface portion so as to be able to conduct heat.

According to the above configuration, the heat-light conversion element is covered on the flat portion of the heat absorbing portion formed in a flat plate shape, so that it is possible to perform efficient heat conduction connection by surface connection. Therefore, since the photoelectric conversion element is surely cooled by the heat absorbing portion, it is possible to avoid a decrease in power generation efficiency and provide a thermophotovoltaic power generation device having high power generation efficiency.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The point is that the surface of the plane portion is mirror-like.

According to the above configuration, the light that has passed through the photoelectric conversion element is reflected by the flat surface portion of the heat absorbing portion, so that the light can be prevented from being converted into heat by the heat absorbing portion. Therefore, it is possible to avoid a decrease in power generation efficiency and provide a thermophotovoltaic power generation device having high power generation efficiency.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The radiation unit includes an infrared transparent substrate formed in a flat plate shape with a material capable of transmitting infrared rays,
The infrared transparent substrate is provided with a heat-light conversion element that radiates radiated light having a predetermined wavelength amplified as the heat radiation source on the flat surface of the flat plate portion , and heat can be conducted to the heat supply unit from the heat supply unit. Is connected to the point.

A so-called infrared transparent substrate has almost no absorption of infrared light. Therefore, the infrared transparent substrate hardly causes radiation in the infrared region.
That is, according to the above configuration, the infrared transparent substrate that emits almost no radiant light, up to the thermo-optical conversion element that radiates radiant light with a predetermined wavelength amplified, without loss of heat energy due to uncontrolled radiation. It is possible to supply heat from the heat supply unit by heat transfer and emit radiated light in which a predetermined wavelength is amplified as radiation.
Therefore, a thermophotovoltaic power generator with high power generation efficiency can be provided.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The radiating section and the photoelectric conversion section are alternately arranged side by side.

According to the above configuration, since the radiation section and the photoelectric conversion section can be arranged in high density in a small space, a thermophotovoltaic power generation device having high power generation efficiency can be provided compactly.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
A point is provided between the heat supply section and the photoelectric conversion section, and a shielding section for shielding radiant light from the supply section is provided.

According to the above configuration, uncontrolled radiant light from the heat supply unit can be prevented from being supplied to the photoelectric conversion unit, so that the photoelectric conversion unit is not heated and a decrease in power generation efficiency can be avoided, resulting in high power generation efficiency. A thermophotovoltaic device can be provided.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The shielding portion is a heat insulating material, and the heat insulating material is provided at a point covered by the heat supply portion.

According to the above configuration, the heat supply unit is covered with the heat insulating material and kept warm.
Therefore, the uncontrolled radiation of the radiant light from the heat supply unit is suppressed, the loss of heat energy is avoided, and the photoelectric conversion unit avoids the heating and the reduction of the power generation efficiency can be avoided. A photovoltaic device can be provided.

A further characteristic configuration of the thermophotovoltaic power generation device according to the present invention is,
The shield part is a light reflector that reflects light, and the light reflector is provided so as to reflect light toward the heat supply part.

According to the above configuration, the radiation from the heat supply unit is returned to the heat supply unit by the light reflector.
Therefore, the uncontrolled radiation of the radiant light from the heat supply unit is suppressed, the loss of heat energy is avoided, and the photoelectric conversion unit can avoid the heating and the reduction of the power generation efficiency. A photovoltaic device can be provided.

The characteristic configuration of the thermophotovoltaic power generation system including the thermophotovoltaic power generation device according to the present invention is:
The thermophotovoltaic power generation device is provided in a vacuum container.

According to the above configuration, it is possible to prevent the heat supply unit from being heated or the photoelectric conversion unit to be heated by convection due to an atmospheric gas such as the atmosphere.
Therefore, a thermophotovoltaic power generation system with high power generation efficiency can be provided.

Sectional drawing which shows the whole structure of a thermophotovoltaic power generator and a thermophotovoltaic power generation system. Schematic diagram of another cross section showing the entire structure of the thermophotovoltaic power generation device and the thermophotovoltaic power generation system. The figure which shows an example of a heat-light conversion element. The figure which shows an example of the spectral radiance of a thermoelectric conversion element. The figure explaining an example of the conversion efficiency of the energy of a thermophotovoltaic generator. The figure which shows another whole structure of a thermophotovoltaic power generator and a thermophotovoltaic power generation system.

A thermophotovoltaic power generation device 100 and a thermophotovoltaic power generation system 1 according to an embodiment of the present invention will be described based on FIGS. 1 and 2.

The thermophotovoltaic power generation device 100 according to the present embodiment has a flat plate-shaped radiating section 10 provided with a thermophoto conversion element 12 as a radiant light source for converting heat into radiant light, and radiant section 10 for the heat supplied from the heat source. And a plate-shaped photoelectric conversion unit 30 including a photoelectric conversion element 31 that receives radiant light and generates electric power.

In the case of this example, as the heat source of the heat supplied to the heat supply unit 20, for example, exhaust heat of a gas engine or a heat source that collects sunlight can be used. Of course, other heat sources can be used and are not limited to a specific heat source. The outer peripheral portion of the heat supply unit 20 is formed of, for example, a metal having a high thermal conductivity such as iron, copper, or stainless. In this example, it is made of stainless steel.

The thermophotovoltaic power generator 100 is stored in the vacuum space 60 of the cooling unit 40 which also serves as the vacuum container 61.
In this example, the space 60 is kept in a vacuum of about 0.01 mPa to 1 kPa.

In this example, the radiation unit 10 is provided upright with respect to the heat supply unit 20 in the vertical direction of the heat supply unit 20 in FIGS. 1 and 2. In this example, the radiation unit 10 is provided at a right angle to the surface of the heat supply unit 20.
Further, the photoelectric conversion unit 30 is installed upright on the cooling unit 40 with the installation direction opposite to that of the heat supply unit 20 that opposes it. In this example, the photoelectric conversion unit 30 is provided at a right angle to the cooling unit 40.
FIG. 2 is a schematic cross-sectional view of another cross section orthogonal to the cross section of the thermophotovoltaic power generation system 1 shown in FIG. FIG. 2 illustrates the radiation unit 10 and the photoelectric conversion unit 30 on the same cross section as a convenience for schematically showing the relationship among the radiation unit 10, the heat supply unit 20, the photoelectric conversion unit 30, and the cooling unit 40. There is.

Therefore, the radiation unit 10 and the photoelectric conversion unit 30 are provided in parallel. Further, the photoelectric conversion unit 30 is provided in a direction orthogonal to the surface of the heat supply unit 20.
Therefore, the uncontrolled radiant light from the surface of the heat supply unit 20 is emitted almost in parallel to the photoelectric conversion unit 30, and the photoelectric conversion unit 30 is not controlled from the surface of the heat supply unit 20. It is possible to avoid being heated by radiant light.

In addition, the radiation unit 10 and the photoelectric conversion unit 30 are provided at a predetermined interval. The radiation unit 10 and the photoelectric conversion unit 30 do not come into physical contact with each other. Therefore, the radiation unit 10 and the photoelectric conversion unit 30 are thermally isolated.

Further, the radiating part 10 and the cooling part 40 are provided with a predetermined space therebetween. The radiation unit 10 and the cooling unit 40 do not come into physical contact with each other. Therefore, the radiation part 10 and the cooling part 40 are thermally isolated.

In addition, the photoelectric conversion unit 30 and the heat supply unit 20 are provided with a predetermined space therebetween. The photoelectric conversion unit 30 and the heat supply unit 20 do not come into physical contact with each other. Therefore, the photoelectric conversion unit 30 and the heat supply unit 20 are thermally isolated.

In this example, as shown in FIG. 1 and FIG. 2, the case where the rectangular flat plate-shaped radiation part 10 and the rectangular flat plate-shaped photoelectric conversion part 30 corresponding to the radiation part 10 are illustrated in a space 60 having a rectangular cross section. However, these examples are for convenience of description and are not limited to these shapes.
Hereinafter, the thermophotovoltaic power generation device 100 and the thermophotovoltaic power generation system 1 will be described in more detail.

The radiating unit 10 includes an infrared transparent substrate 11 for transferring the heat from the heat supplying unit 20 and supplying the heat to the thermo-light converting element 12. That is, the radiation unit 10 includes the infrared transparent substrate 11 and the heat-light conversion element 12.

The radiating portion 10 may be formed to have a height from the heat source of 1 to 10 cm, and in this example, it may be formed in a flat plate shape of about 1 to 10 cm square. If the radiation section 10 is too small, it is economically disadvantageous. If the radiation unit 10 is too large, the heat transfer from the heat supply unit 20 is not sufficient, which is also economically disadvantageous.

The infrared transparent substrate 11 is a material that can transmit infrared rays. In this example, the infrared transparent substrate 11 is formed in a flat plate shape.
Examples of the infrared transparent substrate 11 include magnesium oxide, silicon oxide, silicon silicon carbide (SiC), diamond, sapphire, aluminum nitride, gallium nitride, calcium fluoride, magnesium fluoride, zinc selenium, barium fluoride, zirconium oxide. , Hafnium oxide, titanium oxide, yttria oxide, or the like can be used.
In this example, sapphire is used as the infrared transparent substrate 11.

The infrared transparent substrate 11 is erected on the heat supply unit 20. The infrared transparent substrate 11 and the heat supply unit 20 are thermally in close contact with each other and are connected so that heat can be conducted.
Then, the infrared transparent substrate 11 functions as a support portion that supports the heat-light conversion element 12. The infrared transparent substrate 11 and the heat-light conversion element 12 are thermally close to each other and are connected so as to be capable of heat conduction.
In this example, the infrared transparent substrate 11 is fixed by press-fitting one side of the infrared transparent substrate 11 into a narrow groove provided on the surface of the heat supply unit 20.
Therefore, the heat supply unit 20 and the heat-light conversion element 12 are formed so as to be able to conduct heat through the infrared transparent substrate 11.

In this example, the infrared transparent substrate 11 is provided with a thermo-optical conversion element 12 as a thermo-optical conversion element 12 in the flat plate portion, which radiates radiant light having a predetermined wavelength amplified.
Materials and members suitable for use as the heat-light conversion element 12 include metals such as tantalum and tungsten, semiconductors such as silicon silicon carbide, other insulators, metal or semiconductors or insulators that have been processed with a periodic structure or the like to emit radiation. It is possible to use a member that controls A photonic crystal, which will be described later, is particularly suitable as a member in which radiation is controlled by processing a semiconductor or an insulator such as a periodic structure.

The heat-light conversion element 12 of this example can use a so-called photonic crystal having a predetermined optical structure. The heat-light conversion element 12 has a function of converting the supplied heat into radiant light having a wavelength corresponding to the optical structure, as a photonic crystal.
The heat-light conversion element 12 includes a refraction section 13 made of, for example, a semiconductor, and an optical substrate 14 having a light refraction index smaller than that of the semiconductor of the refraction section 13. The heat-light conversion element 12 of this example receives heat energy from the infrared transparent substrate 11 by heat transfer.

The heat-light conversion element 12 includes a configuration in which the refracting portions 13 are arranged in a square lattice on one surface of the optical substrate 14 formed in a flat plate shape in the direction in which the radiant light is to be emitted.
The arrangement of the refraction portions 13 is not limited to the square lattice shape.
Therefore, the surface provided with the refracting portion 13 is mainly oriented to emit the radiant light, and the surface on the other side is a surface emitting the radiant light having a slightly weaker intensity than the surface provided with the refracting portion 13. That is, the intensity is slightly biased toward the surface side of the optical substrate 14 provided with the refraction portion 13, and the radiant light is radiated from both surfaces of the optical substrate 14.

In the case of this example, the infrared transparent substrate 11 transmits radiant light emitted from both surfaces of the optical substrate 14. Therefore, radiant light is emitted from both sides of the radiating section 10.
The arrangement of the refraction portions 13 is not limited to the square lattice shape. Other arrangements and arrangements may also be included, including, for example, a triangular houndstooth check.
Further, the refraction part 13 and the optical substrate 14 which form the thermo-optical conversion element 12 are not limited to a two-dimensional arrangement/arrangement, and may include a three-dimensional arrangement/arrangement.

The refraction part 13 is formed of a semiconductor. The semiconductor includes an intrinsic semiconductor.
In this example, the refraction part 13 is made of Si crystal.
As the semiconductor that can be used as the refraction portion 13, SiC can be preferably used in addition to the Si crystal. Note that Si and SiC are intrinsic semiconductors.

In this example, the refraction part 13 is formed in a cylindrical shape in a state of protruding on the optical substrate 14. In this example, the heat-light conversion element 12 has a single-layer structure in which the refraction portion 13 is provided on one optical substrate 14.
For example, the diameter d of the refraction part 13 is about 200 nm. The height h of the refraction part 13 is about 500 nm. The refraction portions 13 are arranged in a square lattice, and the period length a of the square lattice (the distance between the centers of the adjacent refraction portions 13) is about 600 nm.

The optical substrate 14 is a substrate capable of transmitting light having a wavelength included in visible light to far infrared light. In other words, it is a substrate that has no absorptance in the visible to far infrared region.
The optical substrate 14 is formed of a material capable of transmitting light having a wavelength included in visible light to far infrared light.

In this example, this optical substrate 14 is an infrared transparent substrate in this example. Specifically, sapphire is used. Further, the optical substrate 14 is configured integrally with the infrared transparent substrate 11 in this example.
Examples of the material used for the optical substrate 14 capable of transmitting light having a wavelength included in visible light to far infrared rays include magnesium oxide, silicon oxide, SiC, diamond, sapphire, aluminum nitride, gallium nitride, calcium fluoride, Magnesium fluoride, zinc selenium, barium fluoride, zirconium oxide, hafnium oxide, titanium oxide, yttria oxide and the like can also be preferably used.

The photoelectric conversion unit 30 is attached to the radiation unit 10 while being supported by the cooling unit 40.
The photoelectric conversion unit 30 may be provided so as to be able to receive the radiant light emitted by the thermo-light converting element 12. For example, the photoelectric conversion element 31 of the photoelectric conversion unit 30 may be provided in a state of facing the radiation surface of the thermo-optical conversion element 12 formed of a flat surface.
In the present example, the photoelectric conversion unit 30 is connected to the cooling unit 40 in a heat conductive state, is provided upright on the cooling unit 40, and is provided in parallel with the radiation unit 10.

The photoelectric conversion unit 30 is a member including a photoelectric conversion element 31 that converts received light into electricity and a heat absorption unit 32 that cools the photoelectric conversion element.
In this example, the photoelectric conversion elements 31 are provided on both flat surface portions (both surfaces) of the heat absorption portion 32 formed in a flat plate shape.
That is, the photoelectric conversion unit 30 can receive the radiant light from the radiating unit 10 on both sides and generate electricity.

The relation between the radiation unit 10 and the photoelectric conversion unit 30 will be supplemented.
In this example, the radiation unit 10 and the photoelectric conversion unit 30 are alternately arranged in the longitudinal direction of the heat supply unit 20 and are provided side by side.
Therefore, the photoelectric conversion elements 31 provided corresponding to both surfaces of the radiation unit 10 respectively receive the radiation light emitted from both surfaces of the radiation unit 10 to generate power.
Further, the radiation unit 10 and the photoelectric conversion unit 30 are provided side by side so as to be alternately repeated, so that the radiation unit 10 having a larger area with respect to the surface area of the heat supply unit 20, that is, the heat-light conversion element 12 is provided. When provided, the heat energy can be efficiently converted into radiant light.

The heat absorption unit 32 is a member that thermally connects the cooling unit 40 and the photoelectric conversion element 31.
The heat absorbing unit 32 is a member having a function of receiving heat from the photoelectric conversion element 31 and transferring the heat to the cooling unit 40.
Further, in the present example, the heat absorption section 32 functions as a support section that supports the photoelectric conversion element 31.

The heat absorbing portion 32 is formed of a metal having a high heat conductivity such as iron, copper, aluminum, duralumin, and stainless steel. In this example, it is formed of a stainless steel flat plate, and this stainless steel flat plate also functions as a member that thermally connects the photoelectric conversion element 31 and the cooling unit 40, and at the same time, a support portion that supports the photoelectric conversion element 31. Is functioning as.

The function of the heat absorption section 32 to thermally connect the photoelectric conversion element 31 and the cooling section 40 can also be realized by using cooling water or a heat pipe.
Therefore, the mode of the heat absorbing unit 32 is not limited to the mode of this example, and a plurality of configurations can be combined, and at least a known configuration can be used.

The heat absorption part 32 is connected to the cooling part 40 in a heat conductive state, is provided upright on the cooling part 40, and is installed side by side in parallel with the radiation part 10. In this example, the heat absorbing portion 32 is fixed to the surface of the cooling portion 40 by welding one side of the heat absorbing portion 32.
The heat absorption part 32 is formed in a flat plate shape, and the photoelectric conversion element 31 is provided on the flat part. Therefore, the photoelectric conversion element 31 is juxtaposed in parallel with the thermoelectric conversion element 12.
Further, the heat absorbing portion 32 is provided in close contact with the photoelectric conversion element 31 so as to be able to conduct heat. In the present example, the photoelectric conversion element 31 is covered by the heat absorption section 32.
Therefore, the cooling unit 40 and the photoelectric conversion element 31 are formed so as to be able to conduct heat via the heat absorption unit 32.

The photoelectric conversion element 31 is a member that converts light into electricity.
As the photoelectric conversion element 31, for example, a general solar cell can be used. For example, silicon solar cells, gallium antimony solar cells, germanium solar cells, indium gallium arsenide solar cells, and gallium arsenide solar cells can be used. Of course, the specific mode of the photoelectric conversion element 31 is not limited to these examples.

When receiving light and generating power, these solar cells generate heat due to relaxation within the band. Therefore, by cooling the solar cell used as the photoelectric conversion element 31 via the heat absorption unit 32, it is possible to avoid a decrease in power generation efficiency due to a high temperature of the solar cell.
Further, when receiving light of long wavelength, these solar cells absorb the light and generate heat. Therefore, by cooling the solar cell used as the photoelectric conversion element 31 via the heat absorption unit 32, it is possible to avoid the solar cell becoming hot and the power generation efficiency being lowered.

The wavelength suitable for power generation of the photoelectric conversion element 31 and the emission spectrum of radiation of the thermo-optical conversion element 12 need to be in a suitable combination because their main parts coincide with each other.
For example, when a silicon solar cell is used as the heat-light conversion element 12, the wavelength peak of the emission spectrum of the photoelectric conversion element 31 is preferably less than 1120 nm. This is because a silicon solar cell cannot generally photoelectrically convert light having a wavelength of more than 1120 nm. When using other solar battery cells, the wavelength peak of the emission spectrum of the photoelectric conversion element 31 can be similarly determined.

The relationship between the thermo-optical conversion element 12 and the photoelectric conversion element 31 will be supplemented.
The members exemplified above as materials suitable for use as the heat-light conversion element 12 have a sharp wavelength spectrum in which a predetermined wavelength of the radiant light is amplified as compared with a so-called black body, and thus have a predetermined photoelectric conversion. By combining with the element 31, high power generation efficiency can be obtained.
Here, the power generation efficiency means the ratio of energy converted into electricity in the input heat energy.

FIG. 4 shows the wavelength spectrum of the radiation of the black body (material is SiC) at 1000° C. (line BB in FIG. 4) and the heat-light conversion using the photonic crystal exemplified in this example at 1000° C. The wavelength spectrum of radiation in the case of the element 12 (line EM in FIG. 4) is illustrated. In FIG. 4, “SP” indicates spectral radiance.
It can be seen that the wavelength spectrum of radiation in the case of the heat-light conversion element 12 using the photonic crystal exemplified in this example has an extremely sharp wavelength spectrum and has a particularly preferable characteristic as a heat radiation light source.

FIG. 5 shows the power generation efficiency when the radiant light of the photothermal conversion element 12 using the photonic crystal exemplified in this example at 1000° C. is received by the silicon solar cell to generate power. In FIG. 5, “Ef” indicates efficiency.
In this example, it can be seen that a conversion efficiency as high as 68% is exhibited at a release voltage of about 0.8v suitable for a silicon solar cell.

The cooling unit 40 is a member that receives the heat supplied from the photoelectric conversion unit 30, does not accumulate the heat, and discharges it to the outside of the system. That is, it is a member that cools the photoelectric conversion unit 30.
The cooling unit 40 can exert its function by cooling with a known cooling method. In this example, the cooling unit 40 is configured such that cooling water flows through the outer wall (container) made of stainless steel. The cooling unit 40 is not limited to this exemplary aspect, and may include other methods and aspects having similar functions.

Hereinafter, more preferable modes of the thermophotovoltaic power generation device 100 and the thermophotovoltaic power generation system 1 will be described.
A shielding unit 50 that shields the radiant light from the heat supply unit 20 may be provided between the heat supply unit 20 and the photoelectric conversion unit 30.
In this example, a light reflector 51 that reflects light is provided as the shielding unit 50 at the end of the photoelectric conversion unit 30 on the side facing the heat supply unit 20, and the light reflector 51 is provided to the heat supply unit 20. It is provided so that the uncontrolled radiant light emitted by the heat supply unit 20 is reflected toward the heat supply unit 20 and is converted into heat again by the heat supply unit 20.

The light reflector 51 may be any one that reflects light. Particularly preferably, the material of the reflecting surface is gold, silver or aluminum, and the material is exposed on the surface.
In this example, a light-reflecting body 51 in which a flat plate made of stainless steel is buff-polished with No. 300 and then electrolytically polished, and gold is vapor-deposited is used.

In the illustration of the thermophotovoltaic power generation device 100 and the thermophotovoltaic power generation system 1 in FIG. 1, utilities such as a supply path used for heat supply from the heat source, cooling water used for cooling, and electric wiring for extracting generated power are Although the description is omitted, known members and methods can be used for these.

[Another embodiment]
(1) In the above embodiment, the example in which the thermophotovoltaic power generation device 100 is stored in the vacuum space 60 of the cooling unit 40 that also serves as the vacuum container 61 has been described.
However, as shown in FIG. 6, the thermophotovoltaic power generation system 1 may be configured by providing a vacuum container 61 separately from the cooling unit 40 and providing the thermophotovoltaic power generation device 100 in the space 60.

(2) In the above embodiment, the radiation unit 10 is provided upright in the vertical direction of the heat supply unit 20 in FIG. 1 with respect to the heat supply unit 20, and the photoelectric conversion unit 30 is opposed to the heat supply unit 20. An example in which the cooling unit 40 is installed upright in the opposite direction to the above.
However, as shown in FIG. 6, the radiating part 10 may be arranged so as to stand upright in only one direction with respect to the heat supply part 20.

(3) In the above embodiment, the radiation unit 10 and the photoelectric conversion unit 30 are alternately arranged in the longitudinal direction of the heat supply unit 20 and are provided side by side.
However, the radiation unit 10 and the photoelectric conversion unit 30 may be alternately arranged in the circumferential direction of the heat supply unit 20 and installed side by side. Specifically, for example, the heat supply unit 20 is formed in a cylindrical shape, the radiation unit 10 is erected on the cylindrical surface of the heat supply unit 20, and the photoelectric conversion unit 30 is provided side by side with the radiation unit 10. May be.

(4) In the above embodiment, as the shielding unit 50, the light reflector 51 that reflects light is provided at the end of the photoelectric conversion unit 30 on the side facing the heat supply unit 20, and The case where the uncontrolled radiant light emitted by the heat supply unit 20 is reflected toward the supply unit 20 and is converted into heat by the heat supply unit 20 is illustrated.
However, as shown in FIG. 6, a heat insulating material 52 is used as the shielding portion 50, and the heat insulating material 52 is provided so as to cover the heat supplying portion 20 so as to suppress uncontrolled radiant light from the heat supplying portion 20. You may comprise.

(5) In the above embodiment, the surface of each member can be a mirror-like light reflector.
For example, the flat portion of the heat absorbing portion 32 formed in a flat plate shape is used as a mirror-like light reflector, so that the radiant light transmitted through the photoelectric conversion element 31 is reflected by the mirror-like light reflector and is again reflected. The energy efficiency is improved because it is returned to the photoelectric conversion element 31, the heat-light conversion element 12, and the heat supply unit 20.
Similarly, it is preferable that the surfaces of the heat supply unit 20 and the cooling unit 40 are mirror-like light reflectors. Also in this case, similarly to the above, the radiant light is reflected by the specular light reflector and is returned to the photoelectric conversion element 31, the heat-light conversion element 12, and the heat supply unit 20, so that the energy efficiency is improved. To do.

Note that the configurations disclosed in the above-described embodiments (including other embodiments, the same applies below) can be applied in combination with the configurations disclosed in other embodiments, as long as no contradiction occurs. The embodiment disclosed in the present specification is an example, and the embodiment of the present invention is not limited to this, and can be appropriately modified within a range not departing from the object of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be effectively used as a thermophotovoltaic power generation device and a thermophotovoltaic power generation system.

1: Thermophotovoltaic power generation system 10: Radiation unit 11: Infrared transparent substrate 12: Thermolight conversion element 20: Heat supply unit (support unit)
30: Photoelectric conversion part 31: Photoelectric conversion element 32: Heat absorption part 40: Cooling part 50: Shielding part 51: Light reflector 52: Heat insulating material 60: Space 61: Vacuum container 100: Thermophotovoltaic power generation device

Claims (10)

A planar radiation portion having a thermal radiation source that converts heat into radiant light to the plane of the flat plate portion, and receives a heat supply portion for supplying the supplied heat to the radiant section from the heat source, the radiant light a flat photoelectric conversion unit provided in the flat portion of the photoelectric conversion element that generates electric power, the thermal photovoltaic device provided with,
The radiating unit is erected on the heat supplying unit so as to be able to conduct heat from the heat supplying unit,
The said photoelectric conversion part is a thermophotovoltaic power generator installed together with the said radiation|emission part in the state which made the said photoelectric conversion element face the said thermal radiation light source. A flat plate-shaped radiating unit provided with a heat radiating light source for converting heat into radiant light, a heat supplying unit that supplies heat supplied from a heat source to the radiating unit, and receives the radiant light. In a flat photoelectric conversion unit having a photoelectric conversion element for generating power in a flat section, and a thermophotovoltaic power generator including:
The radiating unit is erected on the heat supplying unit so as to be able to conduct heat from the heat supplying unit,
The photoelectric conversion unit is provided side by side with the radiation unit in a state where the photoelectric conversion element is opposed to the thermal radiation light source,
A thermophotovoltaic power generation device comprising: the photoelectric conversion unit, which is attached to the radiation unit while being supported by a support unit different from the heat supply unit, and further includes a heat absorption unit that cools the photoelectric conversion element. The said heat absorption part is formed in flat form, the said photoelectric conversion element is provided in the plane part of the said heat absorption part, and the said photoelectric conversion element is connected to the said plane part so that heat conduction is possible. Thermophotovoltaic generator. The thermophotovoltaic power generation device according to claim 3, wherein the surface of the flat surface portion is a mirror surface. The radiation unit includes an infrared transparent substrate formed in a flat plate shape with a material capable of transmitting infrared rays,
The infrared transparent substrate is provided with a heat-light conversion element that radiates radiated light having a predetermined wavelength amplified as the heat radiation source on the flat surface of the flat plate portion , and heat can be conducted to the heat supply unit from the heat supply unit. The thermophotovoltaic power generation device according to any one of claims 1 to 4, which is connected to. The thermophotovoltaic power generation device according to claim 1, wherein the radiation unit and the photoelectric conversion unit are provided side by side alternately. The thermophotovoltaic power generation device according to any one of claims 1 to 6, further comprising a shielding unit that shields radiant light from the heat supply unit between the heat supply unit and the photoelectric conversion unit. The thermophotovoltaic power generation device according to claim 7, wherein the shielding portion is a heat insulating material, and the heat insulating material is provided so as to cover the heat supply portion. 8. The thermophotovoltaic power generation device according to claim 7, wherein the shielding unit is a light reflector that reflects light, and the light reflector is provided so as to reflect light toward the heat supply unit. A thermophotovoltaic power generation system comprising the thermophotovoltaic power generation device according to claim 1 in a vacuum container.

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