JPH07120072A - Solar light converter - Google Patents

Abstract

PURPOSE:To perform a thin solar light converter which efficiently convert a light of energy of a wide spectrum of visible light and infrared ray into heat by condensing the light and converting it. CONSTITUTION:The solar light converter comprises a photoelectric conversion system for photoelectrically converting a solar light and a photothermal conversion system for converting the light into heat, wherein the photoelectric conversion system has condensing means having a transparent lens 1 for condensing and transmitting the light, and a solar cell layer 3 formed of a p-n junction formed between transparent electrodes to generate in response to an incident light amount. The photothermal conversion system has a heat receiver for applying heat received from the light passed through the photoelectric system to an operating medium to be expanded, a drive pump and a circulating pump having a capacity difference, a circulation system of the medium containing a heat dissipating unit for deriving heat from the medium expanded by the receiver 4 to be condensed, and a generator connected to the drive pump and the circulating pump to generate in response to an incident light amount by the circulation of the medium.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for converting solar energy, and more particularly to converting sunlight into electricity and extracting heat.

[0002]

2. Description of the Related Art A semiconductor cell having a pn junction such as silicon single crystal or amorphous silicon has the advantage that it can directly convert solar energy into electric energy and is widely used as a solar cell. .

The conversion efficiency of a general solar cell is 15% for silicon single crystal and 10% for amorphous silicon, and it can be used as a power source from the electronic industry field to the space industry field as a clean solar system. Has been done.

However, even if an attempt is made to further improve the conversion efficiency, the long-wavelength photon that cannot be absorbed, the short-wavelength photon that is not used, and the forbidden band width because the spectrum of sunlight is widely distributed from 0.3 to several microns. About 75% of energy is lost due to loss factors such as the difference between the open circuit voltage and the open circuit voltage, and it is difficult to simply expect high conversion efficiency.

When a solar system constructed by using solar cells having low conversion efficiency is applied to industrial, commercial, residential, etc. purposes, in order to obtain a large amount of electric power, a large number of solar cells are spread over a large area. It is necessary to arrange the element of.

[0006] However, there is a problem that the power generation using the solar cell is much more expensive than the power charge of the commercial power source.

As a measure for improving this, there is provided a device for generating electricity by sunlight and collecting solar heat. This is because an amorphous silicon integrated solar cell is placed inside the vacuum tube, and a solar heat collector tube is placed behind this cell to generate electricity from the incident light to the area of a predetermined area and collect solar heat. It is configured as a hybrid panel that does. In order to apply this hybrid panel to a building, it is convenient to construct it like an exterior material.

However, even if it is used as an exterior material, the production cost of the integrated solar cell is high, and in order to make it easy to apply the conventional vacuum tube type structure to a building, there are various ways to form it as a plate material such as an exterior material. There is a problem. Moreover, since the heat collecting temperature is low, the heat energy is used by heating with a heat pump or the like.

The present invention has been made in consideration of the above points, and provides a thin solar conversion device capable of converting sunlight having a wide spectrum into electricity with high efficiency and extracting it as heat. With the goal.

[0010]

To achieve the above object, the present invention provides a solar light conversion device having a photoelectric conversion system for photoelectrically converting energy of a wide spectrum of sunlight and a photothermal conversion system for photothermal conversion, The photoelectric conversion system is composed of a condensing unit configured by a transparent lens that condenses and transmits sunlight, and a pn junction formed between transparent electrodes, and the sunlight is given through the condensing unit, A heat receiver that has a solar cell layer that generates power according to the amount of incident light, and that the photothermal conversion system applies heat received from the light that has passed through the photoelectric conversion system to a working medium to expand it, and has a capacity difference from each other. A working medium circulation system including a driving pump and a circulation pump, and a heat radiating unit that condenses heat by condensing the working medium expanded by the heat receiver, and the driving pump and the circulation pump. Is coupled to, and provides a photovoltaic conversion device, characterized in that is provided with a, a generator for power generation in accordance with the amount of incident light by the circulation operation of the working medium.

[0011]

In the photoelectric conversion system, the light is condensed by the transparent lens of the light condensing means and given to the pn junction formed between the transparent electrodes.
As a result, the solar cell layer generates electricity according to the amount of visible light. In the photothermal conversion system, the working medium expands due to the heat of the infrared light that has passed through the photoelectric conversion system due to the action of the drive pump and the circulation pump with the capacity difference combined with the heat receiver and the heat emitter in the circulation system, Then, it circulates with compression, and the generator connected to both pumps is driven by this circulation action to generate power according to the amount of infrared light.

[0012]

According to the present invention, the conversion system of the panel can perform photoelectric conversion and photothermal conversion of energy in a wide spectrum of visible light and infrared light with high efficiency. Moreover, it is superior in strength to conventional panels of this type, is inexpensive to manufacture, and because it can be integrated and has optical artistic properties on the lens surface, it can be applied to roofing materials, outer wall materials, etc. It also has the advantage of enabling good buildings. Further, since the heat radiator can be used in the air cooling system, it can be applied to a moving body such as a vehicle or a ship.

[0013]

FIG. 1 is a cross-sectional view of an embodiment of the present invention, which has a panel-like overall structure and a photoelectric conversion system for converting sunlight into electric power, and this photoelectric conversion system. It is equipped with a photothermal conversion system that extracts heat from sunlight that has passed through.

As shown in FIG. 1, the photoelectric conversion system is a solar cell having a three-layer tandem structure.
Further, the photothermal conversion system has a configuration in which the sunlight that has passed through the photoelectric conversion system is thermally converted and the working medium is circulated by this heat, as shown in FIG.

This photoelectric and photothermal conversion system is constructed in the shape of a panel and is used as a roof material for buildings. For example, one panel has an area of about 4800 cm2 and is installed. Then, a glass portion is arranged on the surface layer, and this glass portion is configured such that convex lenses having a diameter of about 0.5 to 1 cm are spread like a honeycomb.

The transparent lens body 1 is formed by such a structure of the glass portion, and sunlight having an incident angle of up to about 50 ° can be condensed to be incident on the surface of the solar cell always or almost vertically. Is configured.

Regarding the manufacturing process and structure of this panel,
Description will be made with reference to FIGS. 1 and 3. As shown in FIG. 3, the solar cell layer 3 is arranged on the back surface of the transparent lens body 1 which is an assembly of spherical lenses. A tin oxide (SnO2) film is formed by CVD on the polymer (EP) layer through electrode lines using the upper transparent electrode 2 as a substrate. A monosilane (SiH4) or disilane (Si2 H6) gas and an impurity gas (diborane B2 H6 for p-type formation, phosphine PH3 for n-type formation) are introduced into the transparent electrode 2, and an RF electric field is applied to continue the electrode. By performing separation plasma CVD, three layers of the pin-type semiconductor structure layer are sequentially formed.

After that, when a tin oxide (SnO2) film is formed, a solar cell layer 3 is formed, and when this is bonded to the transparent lens body 1, a visible light converting means for mainly generating power according to visible light is formed. To be done.

Tin oxide (SnO) in the lower layer of the solar cell layer 3
2) A polymer (EP) layer is formed on the film through an electrode wire, and at the same time, the solar cell layer 3 is sealed with the polymer (EP), and the back surface of the polymer (EP) layer is made of black chrome or the like. By joining the metal 4 coated with the selective absorbing material, an infrared light converting means mainly for converting infrared light into heat is configured. As a result, the resistance of the transparent electrode is reduced and the power loss is reduced.

For the i-layer of the pin-type semiconductor structure, only one layer of the pin-type semiconductor structure for forming a silicon carbide film on the upper layer is used in the case of high-temperature heat collection, and in the case of medium-low temperature heat collection, an intermediate-layer structure is used. Two layers of a pin / pin type semiconductor structure in which a film of germanium, amorphous silicon or the like is formed in the lower layer,
Alternatively, when three layers of a pin / pin / pin type semiconductor structure are adopted, a visible light conversion means having a high conversion efficiency can be realized as a light selective absorption film.

Electric power generated by the solar cell layer 3 mainly by visible light is connected through a conversion circuit 14 to a heater of a heater 15 in an expansion medium collecting pipe provided on the back side of the panel. For this reason, the unexpanded medium can be heated and instantly expanded, and the drive pump 10 can be started easily.

The heat pipe 5 on the back surface of the metal 4 is arranged so as to linearly connect the spherical surfaces of the metal 4. That is, the heat pipes 5 bent into a U-shaped loop made of stainless steel having a diameter of about 2 to 3 mm are arranged in parallel. In the heat pipes 5 in a plurality of rows, the two ends of the tubes, which are all formed in a U-shaped loop shape, are separately connected to the condensing medium supply pipe and the expansion medium collecting pipe provided on the back side of the panel. Has been done. For this reason, metal 4
Conducts heat from infrared light to heat the working medium enclosed in the heat pipe 5. In this way, the infrared light conversion means efficiently performs the conversion operation.

The back surface of the metal 4 is covered with a mixture of polymer fiber material and resin. Therefore, the weight of the panel is reduced and the heat insulating layer 6 is solidified to increase the strength against impact. A panel is supported and attached to a fixed portion connected to a mounting base on the roof side of a building by a metal frame provided around the panel.

A drive pump 10 with a large amount of drainage and a circulation pump 11 with a small amount of drainage are attached to the rotor side face so that the undulating directions due to the loads are opposite to each other. These pumps are generators 12
Together with the same rotary shaft. And both pumps 1
0, 11 and the generator 12 are assembled in a closed container and attached to the back surface of the solar conversion device.

The liquid inlet side of the drive pump 10 is connected to the expansion medium collecting pipe, the liquid outlet side is connected to the inlet side of the heat radiator 20, and the liquid inlet side of the circulation pump 11 is connected to the outlet side of the heat radiator 20. The drain side is connected to the condensing medium distribution pipe. With this configuration, the pressure of the expansion medium is controlled by the drive pump 1.
The drive pump 10 and the circulation pump 11 are operated based on the rotation torque of the drive pump 10 caused by the capacity difference between 0 and the circulation pump 11. To improve the airtightness, a pump, a generator, etc. may be unitized. Pump
Various types such as vane type can be used.

A sufficient amount of gas remains in the reserve tank 25 even when the apparatus is not in operation. This gas is not a vaporized working medium, but is a low boiling point medium such as helium that remains under pressure so that the working medium can condense at around ambient temperature after it has been enclosed, and is reserved when the working medium expands. A change in the volume of residual gas in the tank 25 creates an operating environment for the drive pump. 2 not shown
A flow pipe with a one-way valve is installed between two reserve tanks to automatically reverse the flow of the medium and automatically adjust the amount of working medium circulated.

Since the required torque of the drive pump 10 is proportional to the expansion / contraction change, the working medium is circulated by the drive pump 10 according to the expansion / contraction change of the pressurized gas. Thereby, the cooling of the solar cell performed by the working medium flowing through the heat pipe 5 is stabilized.

The panel of this embodiment has a transparent lens body 1,
Since the solar cell layer 3 including the transparent electrode 2 is joined, heat loss is small. That is, if there is a space between the concentrator and the solar cell, the light arrival rate becomes low as a result of the scattering of light in this space, and the amount of power generated by the solar cell decreases accordingly. Then, there is no space between the transparent lens and the solar cell layer that causes it.

FIG. 4 shows another embodiment of the present invention. In this embodiment, the transparent lens body 1, the solar cell layer 3, the heat receiver, and the heat insulating layer 6 are each formed into a plate shape and then joined together.

FIG. 5 shows the heat radiator 20 having a water cooling structure. This enhances the cooling capacity. In this case, the heat radiator 20 is installed with good ventilation by opening a space between the roof-side mount and the building, and cools and condenses the expansion medium by the vaporization phenomenon of water. In order to effectively use the heat for this condensation, if water is the object of heat exchange, a heat radiator with a small heat radiation loss is provided and used for hot water supply or the like.

FIG. 6 shows still another embodiment of the present invention. In this embodiment, in order to reduce the cost,
The convex lens body made of single-sided glass is used to form a single layer or a multilayer structure by laminating, and it is also possible to prevent heat dissipation and reduce the weight by using a hard resin or the like.

On the back surface of the solar cell layer 3, black
A heat pipe 5 coated with a selective absorbing material 8 such as chromium and a heat receiver 4 made of metal are provided.

FIG. 7 shows how heat is propagated to the working medium of the heat receiver 4 by the selective absorbing material 8.

FIG. 8 shows the structure of a solar cell combined with the embodiment of FIG. The structure and manufacturing procedure are as follows.

To form the upper transparent electrode 2, a thin plate-shaped or film-shaped polymer (EP) is partially embedded with an electrode wire formed by assembling fine wires in a net shape and bonded, and a transparent conductive film (TCO) is formed by CVD. Forming a tin oxide film.

To form the upper layer of the solar cell layer 3, monosilane gas or disilane gas and diborane as an impurity gas are introduced using the transparent electrode 2 as a substrate to introduce p-type amorphous silicon under the action of an RF electric field. To form a film.
Then, i-type amorphous silicon carbide is formed into a film, and then phosphine as an impurity gas is introduced to form an n-type amorphous silicon film.

In order to form the intermediate layer and the lower layer of the solar cell layer 3 in the solar cell layer 3, an amorphous
A pin type layer using germanium is formed into a film. Further, in order to form the lower transparent electrode 2, a T-type film is formed on the back surface of the n-type film.
A tin oxide film of CO is formed, an electrode wire formed by assembling fine wires in a net shape is arranged, and the solar cell layer 3 is sealed at the same time as pressure bonding with a polymer (EP).

The back surface of the polymer layer is covered with a selective absorbing material such as black chrome, and a heat pipe is joined thereto.

The structure of these three layers is a single cell consisting of only the upper layer having good temperature characteristics in the high temperature region for high temperature heat collection, and amorphous silicon capable of selectively absorbing light from the upper layer in the middle and low temperature heat collection. Considering the characteristics of the upper, middle 2
A layer structure or an upper, middle, and lower three-layer structure is used.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross-sectional structure of an embodiment of the present invention.

FIG. 2 is a schematic explanatory view showing a working medium circulation structure in the embodiment of FIG.

FIG. 3 is a partial cross-sectional view showing the structure of a solar cell layer in the example of FIG.

FIG. 4 is a diagram showing a cross-sectional structure of another embodiment of the present invention.

5 is a schematic explanatory view showing a working medium circulation structure combined with the embodiment of FIG. 4. FIG.

FIG. 6 is a diagram showing a sectional structure of another embodiment of the present invention.

FIG. 7 is a schematic explanatory view showing a circulating structure of a working medium in the embodiment of FIG.

FIG. 8 is a partial cross-sectional view showing the structure of the solar cell layer in the example of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparent lens body 2 Transparent electrode 3 Solar cell layer 4 Metal 5 Heat pipe 6 Thermal insulation layer 10 Drive pump 11 Circulation pump 12 Generator 14 Conversion circuit 15 Heater 20 Heat emitter 25 Reserve tank

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F24J 2/42 H F28D 15/02 X G02B 27/00 H01L 31/042

Claims (3)

[Claims] 1. A solar light conversion device having a photoelectric conversion system for photoelectrically converting energy in a broad spectrum of sunlight and a photothermal conversion system for photothermal conversion, wherein the photoelectric conversion system is transparent for collecting and transmitting sunlight. A condensing means composed of a lens, and a pn junction formed between the transparent electrodes,
Sunlight is given through the condensing means, and a solar cell layer that generates power according to the amount of incident light is provided, and the photothermal conversion system is the working medium that receives the heat received from the light that has passed through the photoelectric conversion system. A working medium circulation system including a heat receiver for giving expansion, a drive pump and a circulation pump having different capacities from each other, and a heat discharger for taking heat from the working medium expanded by the heat receiver to condense it; A solar power conversion device comprising: a generator connected to the drive pump and the circulation pump to generate power according to an amount of incident light by a circulating operation of the working medium. 2. The solar conversion device according to claim 1, wherein the photothermal conversion system has a heater to which electric power generated by the solar cell layer is applied, and the heat generated by the heater heats the working medium. Light conversion device. 3. The solar conversion device according to claim 1, wherein the transparent electrode in the photoelectric conversion system is formed by disposing an electrode wire between a polymer layer and a conductive film.