JPH1114161A - Hybrid-type solar cell device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the cooling and heat collection of a solar cell by providing the solar cell on the surface of a heat-collecting plate where a heat-collecting pipe is provided, by providing a transparent plate on the surface of the solar cell via a void layer, and by allowing a selection transparency film where transmittance is high in ultraviolet, visible, and near-infrared ray regions and emissivity is low in a far-infrared ray region to be adhered onto the rear surface of the solar cell. SOLUTION: A solar cell 1 is covered with transparent filler 2 such as ethylene vinyl acetate from both surfaces, and a heat-collecting plate 4 consisting of a metal plate with superior heat conduction and a plastic plate such as polypropylene is mounted on the rear surface of the transparent filler 2. Then, an energy conversion part 6 is constituted of a lead wire 3 for electrically connecting a solar cell 1, the transparent filler 2, and a plurality of solar cells 1 one another, the heat-collecting plate 4, and a heat-collecting pipe 5 being provided on the heat-collecting plate 4, and a transparent plate 7 is arranged via the energy conversion part 6 and a void layer 9. A selection transparency film 8 where transmittance is high in ultraviolet, visible, and near-infrared ray regions and emissivity is low in a far-infrared ray region is adhered onto the rear surface of the transparent plate 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid solar cell device using crystalline silicon, amorphous silicon or the like, and more particularly to a hybrid solar cell device having an improved heat recovery mechanism.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram showing a conventional hybrid solar cell device disclosed in, for example, Japanese Patent Publication No. 4-43838. In the figure, 21 is a glass substrate which is a light-transmitting substrate, and 22 is tin oxide (Sn oxide) on the lower surface of the glass substrate 1.
O ₂ ), a transparent electrode formed by depositing indium oxide (In ₂ O ₃ ) or the like; 23, an amorphous silicon film which is a semiconductor thin film formed on the lower surface of the transparent electrode 2 by a thin film forming process by glow discharge; Reference numeral 24 denotes an aluminum electrode formed on the lower surface of the amorphous silicon film 23 by vapor deposition, 25 denotes a light transmitting in a wavelength region of about 0.8 μm or less which is absorbed by the amorphous silicon film 23, and A heat absorbing layer that absorbs light in a wavelength region longer than about 0.8 μm and transmits the heat,
The heat absorbing layer 25 is formed on the upper surface of the glass substrate 21, and the transparent electrode 22, the amorphous silicon film 23, the aluminum electrode 24, and the heat absorbing layer 25 form the semi-thin film solar cell 2.
6 are constituted.

Reference numeral 4 denotes a heat collecting plate made of a metal having good thermal conductivity such as copper or iron adhered to the lower surface of the aluminum electrode 24 by an insulating adhesive layer 28, and 5 denotes a heat medium tube or a heat medium tube adhered to the heat collecting plate 4. A heat collecting tube composed of a heat pipe, a heat collecting body 27 is constituted by the heat collecting plate 4 and the heat collecting tube 5, and the heat converting body 27 and the glass substrate 21 are connected to a battery to form an energy conversion section 29. The conversion unit 28 is housed in a container made of the light-transmitting plate 7 to constitute a solar energy conversion device 30.

Next, the operation will be described. When light is incident from the glass substrate 21 side, light having a wavelength of about 0.8 μm or less is absorbed by the solar cell 5 and converted into electric energy,
Light having a wavelength longer than about 0.8 μm is absorbed by the heat absorbing layer 25, thereby increasing the heat energy of the heat absorbing layer 25, and transferring the heat energy to the heat collector 27 via the solar cell 26. It is configured to be
It effectively converts light energy over the entire wavelength range of sunlight into heat and electrical energy.

[0005]

As described above,
The conventional hybrid solar cell device has a structure in which amorphous silicon is used for the solar cell. Therefore, in a crystalline silicon solar cell widely used in a normal solar power generation system, the absolute value of the solar cell shown in FIG. As shown in the spectral sensitivity characteristics, since there is sensitivity in the wavelength range of 0.3 to 1.2 μm, the power generation efficiency is reduced unless the light is 0.8 μm or less. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a crystal which can easily manufacture a solar cell with a simple structure, has high reliability, and can efficiently perform cooling and heat recovery. It is an object of the present invention to provide a hybrid solar cell device using system silicon, amorphous silicon, or the like.

[0007]

A solar cell device according to the present invention includes a heat collecting plate provided with a heat collecting tube through which a heat medium to collect heat flows, a solar cell provided on the surface of the heat collecting plate, A transparent plate provided with a gap layer on the surface of the solar cell, and a high transmittance in the ultraviolet, visible, and near-infrared regions, and a low emissivity in the far-infrared region. A permeable membrane.

Further, the thickness of the permselective membrane is increased from the entrance to the exit of the heat collection tube.

In addition, an inert gas is sealed in the void layer.

Further, a latent heat storage material which changes phase at a predetermined temperature is fixed to the back surface of the heat collecting plate.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a hybrid solar cell device according to Embodiment 1, and FIG. 2 is a perspective view of the hybrid solar cell device. In the figure, 1 is a solar cell made of crystalline silicon, amorphous silicon or the like, 2 is a transparent filler such as ethylene vinyl acetate, etc., which wraps the solar cell 1 from both sides, and 3 is an electrically connected solar cell. The lead wire 4 to be connected is a heat collecting plate made of a metal plate having good heat conductivity such as copper, aluminum, iron or the like or a plastic plate such as polypropylene attached to the back surface of the transparent filler 2, and 5 is a heat collecting plate 4. The heat collecting plate 4 is connected so as to conduct heat.
A heat collection tube, 5a is a heat collection tube inlet, and 5b is a heat collection tube outlet, which is a heat medium flow path for collecting the heat of the above. Reference numeral 6 denotes an energy conversion unit including a solar cell 1, a transparent filler 2, a lead wire 3, a heat collection plate 4, and a heat collection tube 5, and 11 denotes an energy conversion unit.
Is a heat insulating material disposed on the back surface of the. Reference numeral 7 denotes a transparent plate disposed via the energy conversion unit 6 and the gap layer 9, reference numeral 8 denotes a permselective membrane attached to the back surface of the transparent plate 7 such as glass, and reference numeral 12 denotes a case.

The selectively permeable film 8 has such characteristics that the transmittance is high in the ultraviolet, visible and near infrared regions, and the emissivity is low in the far infrared region. That is, based on a light wavelength of about 2 μm, which is a boundary between the near-infrared region and the far-infrared region, a wavelength lower than this has a higher transmittance and a wavelength higher than this has a lower emissivity. The permselective membrane 8 is made of, for example, Ag, Al, A
Metals with low emissivity in the far-infrared region, such as u, Cr, Cu, Ni, Ti, or thin films or semiconductor materials with a structure sandwiched by dielectrics with a large refractive index are doped with impurities to emit in the far-infrared region There is a transparent conductive film or the like having characteristics with a low rate.

Next, the operation will be described. Light is transparent plate 7
When the light enters from the side, the light passes through the transparent plate 7, the selectively permeable film 8, the gap layer 9, and the transparent filler 2 to reach the solar cell 1. If the solar cell 1 is, for example, crystalline silicon, light is not transmitted, and most is absorbed by the solar cell 1. At this time, the power generation efficiency of the solar cell 1 is converted into electricity, and the remainder becomes heat, which moves to the filler 2, the heat collecting plate 4, and the heat collecting tube 5 by heat conduction, and a heat medium flowing through the heat collecting tube 5. Heat is exchanged by convective heat transfer to recover heat.

On the other hand, heat loss occurs due to convection and radiation from the high temperature energy converter 6 toward the transparent plate 7. Heat loss due to convection can be prevented by the void layer 9,
The heat loss due to radiation is usually 0.9% or more, the emissivity of transparent glass used for the transparent plate 7 and the emissivity of ethylene pinyl acetate used for the transparent filler 2 are the same as those of black paint. In the case of, heat loss due to radiation is inevitable. However, the selectively permeable film 8 has an emissivity of 0.9 in the far infrared region.
Since it is less than the above, radiation is small and heat loss due to radiation is prevented.

The emissivity of the selectively permeable film 8 is between 0.2 and 0.8 depending on the use of the solar cell. FIG. 3 shows the effect of the permselective film 8. When the emissivity is 0.2 to 0.8, the heat collecting effect is about 40 to 50%.

As described above, in the first embodiment, since the permselective film 8 is attached to the back surface of the transparent plate 7 irrespective of the type of the solar cell, radiation heat loss from the front transparent plate 7 is prevented. The heat collection efficiency of the heat collection tube 5 can be improved, and the effective use of energy can be achieved in addition to power generation and heat recovery. In addition, since the permselective membrane 8 is easily attached to the transparent plate 7, manufacturing can be facilitated.

Embodiment 2 FIG. In the second embodiment of the present invention, in the configuration shown in FIGS. 1 and 2 of the first embodiment, the thickness of the permselective membrane is increased from the inlet to the outlet of the heat collection tube. Is decreased from the heat collecting tube inlet 5a toward the heat collecting tube outlet 5b.

The operation of the above configuration will now be described. The heat medium flows in from the heat collecting tube inlet 5a, is collected by the energy conversion unit 6, and the temperature of the heat medium rises toward the heat collecting tube outlet 5b. This will be described with reference to the heat collection efficiency diagrams of FIGS. In the figure, the vertical axis represents the heat collection efficiency η = heat collection amount / light intensity (solar radiation), and the horizontal axis represents the heat collection efficiency variable R = (heat collection temperature−outside air temperature) / light intensity (solar radiation).
Expressed by Here, when the emissivity of the permselective membrane 8 is the same from the heat collecting tube 5 to the heat collecting tube outlet 5b in the direction from the heat collecting tube inlet 5a to the heat collecting tube outlet 5b, as shown in FIG. The heat collection efficiency η of the section will decrease. FIG. 4B shows a case where the emissivity of the permselective membrane 8 is formed so as to decrease from the heat collecting tube 5 to the heat collecting tube outlet 5b in the direction of the heat collecting tube inlet 5a.
6A is a heat collection efficiency diagram when the emissivity is high, and B is a heat collection efficiency diagram when the emissivity at the heat collection tube outlet 5b is low. As shown in the figure, since the emissivity decreases from the heat collecting tube inlet 5a (high emissivity) toward the heat collecting tube outlet 5b (low emissivity), the heat collecting efficiency η does not decrease.

As described above, since the emissivity of the permselective membrane 8 is reduced from the inlet 5a of the heat collecting tube to the outlet 5b of the heat collecting tube, the heat collection efficiency η increases from the inlet of the heat collecting tube to the outlet of the heat collecting tube. Without reducing the heat recovery.

Embodiment 3 The third embodiment of the present invention is the same as the first embodiment except that an inert gas is sealed in the void layer 9 shown in FIG.

The operation of the above configuration will now be described. Usually, air contains moisture, and the air gap layer 9
If it is air, it contains some water. Permselective membrane 8, for example, Ag, Al, Au, Cr, Cu,
In the case of a metal thin film such as Ni or Ti having a low emissivity in the far-infrared region, it reacts with moisture in the air to become an oxidized compound, and when oxidation or deterioration occurs, heat loss may increase. Here, if an inert gas such as nitrogen is sealed in the void layer 9, deterioration of the permselective membrane 8 can be prevented, and a decrease in the transmittance of the transparent plate 7 due to dew condensation in winter can be prevented. .

As described above, since the inert gas such as nitrogen is sealed in the gap layer 9, deterioration of the permselective membrane 8 can be prevented, and the transmittance of the transparent plate 7 due to dew in winter can be reduced. Can be prevented, and the reliability can be increased.

The same effect can be obtained by evacuating the inside of the gap layer 9 or installing a drying agent such as silica gel.

Embodiment 4 Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a cross-sectional view of the hybrid solar cell device showing the embodiment. FIG.
The same or corresponding parts are denoted by the same reference numerals and description thereof will be omitted. In the figure, reference numeral 13 denotes a latent heat storage material provided between the back surface of the energy conversion unit 6 and the heat insulating material 11.

Next, the operation will be described. If heat is not collected when the solar radiation is strong and the outside air temperature is high in summer or the like, the temperature of the energy conversion unit 6 rises to 100 ° C. or more. At this time, for example, if the latent heat storage material 13 that changes phase at 50 ° C. is arranged, the temperature of the energy conversion unit 6 rises only up to around 50 ° C. In addition, it is possible to prevent the energy conversion unit 6 from deteriorating due to heating and breaking due to thermal expansion. It is preferable that the latent heat storage material 13 changes its phase at 30 to 60 ° C., and examples thereof include sodium sulfate-based, sodium acetate-based, and paraffin-based latent heat storage materials.

As described above, in this embodiment, since the latent heat storage material 13 is arranged on the back surface of the energy conversion unit 6, when heat is not collected when the solar radiation is strong and the outside air temperature is high in the summer, etc. A highly reliable hybrid type that can suppress a rise in temperature of the conversion unit 6 and prevent a decrease in power generation efficiency of the solar cell 1 due to a rise in temperature, and also prevent deterioration of the energy conversion unit 6 due to heating and destruction due to thermal expansion. A solar cell device can be obtained.

Normally, the collected heat medium is stored in a heat storage tank (tank) and supplied to the load side. However, the latent heat storage material 13 can be used instead of the heat storage tank. It can also be applied to tankless systems, which are not hot water supply systems.

[0028]

Since the present invention is configured as described above, it has the following effects.

[0029] A solar cell device according to the present invention includes a heat collecting plate provided with a heat collecting tube through which a heat medium for collecting heat flows, a solar cell provided on the surface of the heat collecting plate, and a gap formed on the surface of the solar cell. A transparent plate provided with a layer, and a selectively permeable film attached to the back surface of the transparent plate, having a high transmittance in the ultraviolet, visible, and near-infrared regions, and a low emissivity in the far-infrared region. Therefore, radiant heat loss can be prevented, heat collection efficiency can be improved, and energy can be effectively used by combining power generation and heat recovery.

Further, since the thickness of the permselective membrane is increased from the inlet to the outlet of the heat collecting tube, heat can be efficiently collected without decreasing the heat collecting efficiency from the inlet to the outlet. Can be done.

Further, since the inert gas is sealed in the void layer, it is possible to prevent the permselective membrane from deteriorating and to prevent the transmittance of the transparent plate from deteriorating due to dew condensation in winter.

Further, since a latent heat storage material that changes phase at a predetermined temperature is fixed to the back surface of the heat collecting plate, when heat collection is not performed, the temperature rise of the energy conversion unit is suppressed, and the power generation of the solar cell due to the temperature rise is suppressed. While preventing a decrease in efficiency,
It is possible to prevent deterioration of the energy conversion unit due to heating and breakage due to thermal expansion.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a hybrid solar cell device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a hybrid solar cell device according to Embodiment 1 of the present invention.

FIG. 3 is a diagram showing an effect of the permselective membrane according to the first embodiment of the present invention.

FIG. 4 is a heat collection efficiency diagram according to Embodiment 2 of the present invention.

FIG. 5 is a sectional view of a hybrid solar cell device according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram of a conventional hybrid solar cell device.

FIG. 7 is an absolute spectral sensitivity characteristic diagram of a solar cell.

[Explanation of symbols]

Reference Signs List 1 solar cell, 2 transparent filler, 3 lead wire, 4 heat collecting plate, 5 heat collecting tube, 5a heat collecting tube inlet, 5b heat collecting tube outlet, 6 energy conversion unit, 7 transparent plate, 8 selective permeable membrane, 9 void layer, 11 heat insulation layer, 12 cases, 13
Latent heat storage material.

Claims (4)

[Claims] 1. A heat collecting plate provided with a heat collecting tube through which a heat medium to collect heat flows, a solar cell provided on a surface of the heat collecting plate, and a solar cell provided on a surface of the solar cell via a gap layer. A hybrid type comprising: a transparent plate; and a selectively permeable film attached to a back surface of the transparent plate and having a high transmittance in an ultraviolet region, a visible region, and a near infrared region, and a low emissivity in a far infrared region. Solar cell device. 2. The hybrid solar cell device according to claim 1, wherein the thickness of the permselective membrane is increased from the inlet to the outlet of the heat collection tube. 3. The hybrid solar cell device according to claim 1, wherein an inert gas is sealed in the void layer. 4. The hybrid solar cell device according to claim 1, wherein a latent heat storage material that changes phase at a predetermined temperature is fixed to the back surface of the heat collecting plate.