JPH0734661B2 - Solar energy converter - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a solar energy conversion device, and in particular, a device that mainly enables efficient photoelectric conversion, but also photothermal conversion if necessary. Regarding

[Prior Art] The solar cell element itself as a photoelectric conversion element is being improved more and more, and in particular, conversion efficiency, fill factor, open electromotive voltage, etc.
In recent years, various electrical characteristics of a single element have been improved.

However, when actually producing a solar energy conversion device using such an element and putting it into practical use, it is not used by itself as a matter of course, but a large number of these elements, generally a plate-shaped substrate. If you use the solar cell module integrated on the above and also do not use some efficient solar light absorption means or a condensing means such as mirrors and lenses, you can satisfy the overall conversion efficiency of the system and eventually the power capacity. It cannot be raised to any level.

Therefore, in addition to the development technology for improving the characteristics of the photoelectric conversion element alone, a solar cell using these elements and some other member are combined to increase the efficiency or generated power capacity of the entire device or system. Attempts have also been made differently.

Among them, as a proposal for converting the energy of each wavelength band emitted by sunlight into electric energy as efficiently as possible, there is one using fluorescent particles as shown in FIG.

As is well known, there are some photoelectric conversion elements that use different materials for the bulk part involved in the photoelectric conversion mechanism, such as crystalline silicon type, amorphous silicon type, and compound semiconductor type. Although the wavelength regions shown are different, generally speaking, good sensitivity characteristics can be generally recognized in common at 5500Å or higher.

On the other hand, the wavelength band included in sunlight has a sufficiently wide region below (shorter) than that.

Therefore, if the provided solar cell is simply exposed to sunlight, part of the provided solar energy is wasted.

Therefore, as shown in FIG. 5 (A), the sunlight L _S to be irradiated is not directly incident on the solar cell 10, but is first incident on the transparent plate 11 in which an appropriate amount of fluorescent particles n ₁ are encapsulated. , The adhesive 12 on the end face of the transparent plate 11 while reflecting inside the transparent plate.
There is one that is led to the solar cell 10 fixed by.

By doing so, among the wavelength components of sunlight propagating in the transparent plate 11, the light components in the wavelength region outside the high sensitivity region indicated by the solar cell 10 are also included in the transparent plate 11 in an appropriate amount. By being absorbed by the fluorescent particles n ₁ which are present, converted in wavelength, emitted, and radiated, it is possible to convert into light in a wavelength region that can be efficiently absorbed in the solar cell 10.

In FIG. 5 (A), the transparent plate 11 is composed of a stack structure (11 _-1 , 11, _-2 , 11 _-3 ) with suffixes, and these transparent plates 11 _-1 , 11, _-2 , 11 _{-are provided. 3} to solar cells 10 _-1 , 10
_-2 , 10 _-3 is provided for each transparent plate 11 _-1 , 11 _-2 , 11
_This is because the fluorescent particles n ₁ , n ₂ , and n ₃ contained in _-3 are made different and the wavelengths to be converted are made different, so that a wider sunlight wavelength range is used for photoelectric conversion. Therefore, of course, the illustrated three-ply stack is merely an example, and in principle, an arbitrary number of stacked structures can be formed.

Although the concept is the same, as shown in FIG. 5 (B), instead of using the irradiation light from the end surface of the transparent plate, similarly, fluorescent particles ni (suffix i is an arbitrary kind, an arbitrary number of fluorescent particles The solar cell 10 is attached with an adhesive 12 along the main surface portion of the transparent plate 11 in which the solar cell 10 is encapsulated, and it is desirable that the area other than the area where the solar cell is attached has a mirror surface or a diffusion surface. There is also a structure in which a reflector 14 having is formed.
Not only the reflecting plate 14, but also the sunlight that tries to pass through the transparent plate 11 is returned to the inside of the transparent plate 11 to increase the efficiency of use of sunlight.

As described above, conventionally, there is a technology that attempts to perform photoelectric conversion by using the provided solar energy in consideration of its wavelength as little as possible, but on the other hand, a device that also performs photothermal conversion along with photoelectric conversion, That is, a device system that also tries to extract heat energy from sunlight has also been proposed.

Each of FIG. 6 shows an example of such a conventional device. First, in FIG. 6A, a plurality of solar cells 10 and an outer case are housed in a box-shaped outer case 16 containing a heat insulating material 15. It has a structure in which a heat collecting tube 20 that reciprocates inside is housed and then a lid is covered with a glass cover 18, and a heat collecting plate 19 such as a roll bond plate or a fin is thermally coupled to the heat collecting tube 20, and this is It is fixed on the inner bottom of the outer case 16 via a heat insulating material 17.

A suitable fluid heat medium is flowed in the heat collecting tube 20, and
Thermal energy is provided by sunlight L _S other than incident on the solar cell 10 housed above it in the outer case.

The structure of FIG. 2B is also the same in principle, except that a solar cell 10 is sandwiched between a pair of glass covers 18, 18, and a module structure is used. A so-called black liquid 22 is selected as a heat transfer medium flowing in the glass tube, and directs the sunlight Ls into the heat collecting glass tube 21 to generate a black liquid.
Heat is absorbed at 22.

Lastly, the structure shown in FIG.
The solar cell 10 is directly arranged on the heat collecting plate 19 provided between the heat collecting tubes 20 and 20 while being thermally coupled to the heat collecting tubes 20 and 20, and other structural parts are the same in the figure. As can be seen from the use of the reference numerals, it is almost the same as the above two examples.

In any case, in such a conventional device, not only the solar energy is directly converted into electric energy as a so-called hybrid type solar energy conversion device,
It is also possible to use the heat energy of sunlight as heat energy as it is, and if this is converted into electric energy from an appropriate heat exchanger and then through a power generation system, this can be converted into electric power generated by direct power generation from solar cells. Thermoelectric power can be added.

[Problems to be Solved by the Invention] Each of the conventional devices shown in FIGS. 5 and 6 has a useful aspect to some extent. However, not only the illustrated conventional example but also considering the basic structure in which the solar cell is simply exposed to sunlight, the most problematic issue is the temperature rise of the solar cell during actual operation.

According to recent reports, the conversion efficiency as a photoelectric conversion element exceeds 10% even if it is an amorphous type, and it is expected that higher efficiency will be achieved in the future. However, such efficiency is often discussed at room temperature, and in reality, the efficiency decreases by about 10% each time the temperature rises by 10 ° C.

Therefore, when such a photoelectric conversion element is used as a device for converting solar energy, which is the subject of this document, even if it is placed directly under atmospheric environment, the temperature of the solar cell is (temperature It may be easy to reach around +50) ° C, and a condenser mirror or condenser lens is used, or, as seen in the previous example, a transparent plate structure containing fluorescent particles or a sealed structure inside an outer case. If they are adopted, they may be structurally difficult to cool,
If it gets worse, it can reach several hundred degrees Celsius.

In other words, the most basic problem in this type of solar energy conversion device is, in the meantime, to cool the solar cell to be used, but in the past, at most, to the extent that a radiation fin is attached to the solar cell module. It was not enough.

For example, even in the conventional structure as shown in FIG. 6 (C), the heat medium flow flowing through the heat collecting tube 20 cools the solar cell 10 closely arranged on the heat collecting plate 19. However, due to the fact that the glass cover 18 is hermetically sealed in the outer case 16, the heat collecting plate 19 itself becomes considerably hot, and a cooling effect can hardly be expected.

As described above, regarding cooling, the conventional structure including the structures shown in Figs. 5 and 6 remained the basic problems, but the conventional examples shown in Figs. 5 and 6 were devised. Considering each of the individual parts made, there are still drawbacks to be improved.

First, considering the structure shown in FIG. 5, both the structure shown in FIG. 5A and the structure shown in FIG. 5B are actually located between the solar cell 10 and the transparent plate 11 containing the fluorescent particles ni in an appropriate amount. Since it has a structure in which a suitable adhesive 12 is interposed and is mechanically combined, it has a structure in which many boundary surfaces are optically formed, and in some cases, due to imperfect filling of the adhesive or the like, a gap is formed in the optical path. May occur.

Such boundaries and voids cause light loss such as light reflection, diffusion, absorption, and refraction, and are extremely undesirable.

Further, in reality, the transparent plate 11, the adhesive 12, and the solar cell 10 have different thermal expansion rates and temperature rising rates, and therefore their mechanical dimensional changes cause larger voids to increase the loss, or the worst case. In that case, it was sometimes followed by the destruction of mechanical devices. Even if cooling is considered to prevent this, in such a structure, it is extremely impossible to control them at the same temperature rising rate.

Further, there is a problem in the structure in which the fluorescent particles ni are filled and fixed in the transparent plate 11.

As is well known, phosphors of any kind are essentially aged. Moreover, many things do not last many years. Therefore, in the structure shown in FIG.
The transparent plate 11 has to be replaced on a fairly frequent basis for the ni only, and not only
Considering that is fixed to the transparent plate 11 with the adhesive 12, eventually the expensive solar cell 10 which is still fully usable must be discarded and replaced with a new structure. It goes without saying how wasteful this is. The time and effort required for replacement are not negligible, and the operation of the system must be stopped during its maintenance work.

On the other hand, the hybrid type device shown in FIG. 6 is not desirable in that it is a device structure that is basically difficult to cool as described above, but rather a device structure that allows a temperature rise like a greenhouse. 6 As is clear from each figure, the heat collecting plate 19 is in the “shadow” of the solar cell 10, and it is hard to say that the utilization efficiency of solar energy is sufficiently high in this respect. In addition to the case where the solar cell 10 is above the heat collecting tubes 20 and 21, as shown in the figure, even if one considers a structure in which the vertical relationship is reversed, the solar cell is eventually provided in a plan view. The heat collecting tube must be arranged in the non-exposed portion, and the heat collecting plate under the solar cell, for example, and the solar cell under the heat collecting plate in the reverse structure, etc., become the shaded portions.

The present invention has been made in view of the above conventional circumstances, and has the following objects.

The most basic problem to be solved is to provide a structure that can sufficiently and reasonably cool a solar cell.

Even if the efficiency of sunlight is increased by converting the wavelength of sunlight by using fluorescent particles, there is no defect like the conventional transparent plate structure has. Provide a structure with low loss and easy replacement and maintenance of fluorescent particles.

Furthermore, in the case of configuring a so-called hybrid type solar energy conversion device that can extract not only solar energy into electric energy but also thermal energy, a device that can easily and rationally realize this. To provide.

[Means for Solving the Problems] In order to achieve the above-mentioned problems (1) to (3), in the present invention, a heat transfer medium that is highly transparent to sunlight and is made of a fluid material is used, and the heat transfer medium flows. Put the solar cell inside,
We propose a basic structure for thermally coupling the solar cell and the heat transfer medium.

In order to thermally couple the solar cell and the heat transfer medium stream, it is easy and efficient to contact the surface of the solar cell directly with the heat transfer medium stream. A fin or the like that is thermally coupled and has a high thermal conductivity may be provided so that the fin portion directly contacts the heat medium flow.

Of course, at least the built-in solar cell is provided with a window in a part thereof so that sunlight can be applied to the built-in solar cell.

However, the term “window” here has an optical meaning, and its shape does not matter. Therefore, as a matter of course, the case where the entire sealed container is made of a transparent material such as glass is naturally included. In other words, it can be seen that such a wholly transparent sealed container constitutes its entrance window with respect to sunlight, and conversely, in such a sealed container, the sunlight is actually built-in. The transparent wall surface portion of the container through which the sunlight penetrates when irradiating the solar cell may be defined as a window.

In such a structure, the present invention also proposes to use means for intentionally promoting the turbulent flow generated in the heat transfer medium flowing in the sealed container.

Furthermore, the present invention, by using fluorescent particles,
At least one type with appropriate concentration for the heat transfer medium flowing in the sealed container, which is suitable for converting the solar components in the low sensitivity wavelength region of the solar cell into the high sensitivity wavelength region for use. A configuration in which the above fluorescent particles are mixed is also proposed.

On the other hand, by using the heat transfer medium flowing in the sealed container as a heat collection medium, it is suitable for constructing a hybrid device having both photoelectric conversion function and photothermal conversion function. It is also proposed to provide a heat exchanger for taking out the amount of collected heat.

[Operation] In the solar energy conversion device of the present invention described in claim 1 of the present application, the heat transfer medium flowing in the sealed container is always thermally coupled to the solar cell provided in the sealed container. Therefore, when the solar light is incident on the solar cell, the solar cell is forcibly cooled by the heat medium flow while the photoelectric conversion is performed.

Therefore, even with this type of solar energy conversion device which is destined to be continuously exposed to direct sunlight for a long time, it is possible to well suppress the decrease in efficiency due to the temperature rise of the solar cell.

Further, according to the apparatus configuration described in claim 2 of the present application, when the heat medium turbulent flow promoting means is used, a sufficient turbulent flow occurs in the heat medium flow flowing in the closed container, and the sun housed in the same closed container. Since the battery can be uniformly cooled, the conversion efficiency can be improved in the end.

In addition, when the device configuration according to claim 3 of the present application is also adopted and an appropriate amount of fluorescent particles is mixed in the heat transfer medium, the fluorescent particles are relative to each other in the solar cell used. Operates the action of wavelength conversion of sunlight components in the wavelength region that belongs to the low sensitivity region to the relative high sensitivity region of the solar cell,
Overall, the utilization efficiency of sunlight is improved.

Moreover, unlike the case of the conventional example described above, the fluorescent particles are directly mixed in the heat medium flowing as a fluid, and particularly physical or mechanical is provided between the heat medium flow and the solar cell. Since it is not necessary to have a specific boundary surface, incident sunlight and light whose wavelength is converted by fluorescent particles are not lost by such a boundary surface, which also improves the conversion efficiency of solar energy. Contribute.

Also, even if the fluorescent particles in the heat medium become unusable due to aging, a new amount of fluorescent particles is newly added to the flowing heat medium,
It is extremely easy to replenish by dropping it, and even components that are still fully usable, especially solar cells,
There is no need to replace it regularly.
Further, even if such a fluorescent particle replenishing operation is performed, it is often not necessary to stop the operation of the system using the present solar energy conversion device.

Even if replacement of old fluorescent particles is required instead of replenishment, in the case of the device of the present invention, only the heating medium in which the fluorescent particles are mixed or dissolved is replaced, and new fluorescent particles are mixed in Of course, it is not necessary to replace the solar cell and other fixing members, and in some cases, such a heat medium flow replacement operation can be performed while the system is operating.

On the other hand, basically, the heat medium used for the forced cooling of the solar cell as described above itself acts as a heat collecting medium that carries the amount of heat absorbed from the sunlight, and thus the heat medium according to claim 4 of the present application. According to the configuration described in 1 above, using a suitable heat exchanger which may itself utilize known heat exchange technology, if the heat quantity held by the heat medium is taken out as the output heat quantity, this is used as it is as the heat energy for the hot water system. It can be converted into electric energy through a suitable power generation system such as having a steam turbine, etc., and is extremely rational as a hybrid solar energy conversion device in any case. It can be a device.

However, the above heat exchanger is also necessary in that sense, considering that the heat medium flow is generally circulated. That is, the amount of heat of the heat medium flow that has obtained the amount of heat by cooling the solar cell in the sealed container is reduced, and the temperature thereof is sufficiently lowered before being poured into the sealed container again.

[Examples] FIG. 1 shows an example of the main configuration of a solar energy conversion device 30 constructed according to the present invention.

In the case of this embodiment, there is an elongated cylindrical sealed container 31,
It is made of transparent glass or transparent resin as a whole. Even resins that have sufficiently high heat resistance are now readily available.

2 (A) to 2 (C) also show the structure inside the hermetically-sealed container 31, the description will be given below with reference to FIG. 2 as well. The solar cell 32 is inserted along the length direction so as to straddle the diameter portion,
A transparent sealed container for the main surface (front surface) of this solar cell 32
The sunlight L _S enters through a part of the wall surface of 31.

As a result, when the photoelectric conversion function is generated in the solar cell, the photoelectric conversion current based on the generated electromotive voltage is a pair of current leads at both ends that are schematically shown only in FIGS. 2A and 2B. It can be taken out from 33, 33 to an external load circuit system (not shown). The configuration of the external load circuit system is
In this type of solar cell utilization technology, it may be the same as an existing circuit system required for various types of utilization equipment, and the present invention does not directly limit these.

In the same manner, the solar cell 32 itself may be prepared by a known technique, and is generally formed by electrically connecting a plurality of solar cell segments on a common substrate in series or series-parallel. It may be formed in a geometric shape suitable for being housed in the sealed container 31.

In this case, the sealed container 31 has an inlet 35 and an outlet 36 for the heat medium at each end in the lengthwise direction. In the figure, they are literally shown as mere narrow openings, but here they are preferably detachably connected to an external pipe, as appropriate for the piping process required for the heat medium circulation system described below. It may have a connector or the like that can. The connector is
For example, it may be one that is found in a water pipe system or something similar thereto, and includes a simple connection flange structure and the like, and is not particularly limited.

Inside the sealed container 31, from the inflow port 35 toward the outflow port 36,
The heat medium 37 represented by the arrows in FIGS. 1 and 2 flows. However, for convenience of explanation at that time, the reference numeral 37 may indicate the heat medium itself or the flow of the heat medium.

In the illustrated embodiment, an example of circulating use of the heat medium 37 is shown,
Therefore, there is a pump unit 38 that feeds the heat medium 37 toward the inflow port 35 of the sealed container 31 first, while the heat medium 37 discharged from the outflow port 36 of the sealed container 31 is for cooling the heat medium. In addition, or as described below,
After passing through a heat exchanger 39 for effectively using the transferred heat energy in an external device system (not shown), it is input again to the circulation pump section 38.

Further, a fluorescent particle supply unit 40, which will be described later, is provided in the heat medium passage between the output of the pump unit 38 and the inflow port 35 of the sealed container 31.

However, the heat medium 37 used in such a circulation system is as transparent as possible to the sunlight L _S , is chemically stable, and is physically stable with respect to the solar cell 32 built in the sealed container 31. , A material that does not adversely affect the chemical or electrical properties, and as such a material, for example, a synthetic paraffin-based organic solvent called trade name SHMS S-2, SH-4, SH-6, etc. Other examples include PS-5, an organic solvent, and most commonly, silicone oil. In particular, if the heat medium 36 is electrically insulative, it is not necessary to provide the solar cell 32 housed in the hermetically sealed container with a particularly large insulating structure, which simplifies the process.

The above-described first and second illustrated devices operate as follows.

By the function of the circulation pump unit 38, the heat medium 37 is circulated so as to pass through the sealed container 31, and the sealed container is exposed to sunlight L _S.
Irradiating the built-in solar cell 32 to 31 and photoelectrically converting it, where there is no heat medium 37 under the actual use environment, the temperature of the solar cell 32 rises to an extremely high value,
In the case of this embodiment, the heat medium 37 is constantly flowing while directly touching the surface (front and back) of the solar cell 32.
32 can be forcibly cooled efficiently. As you can see,
Since the circulating use of the heat medium is considered in this embodiment, the circulation pump 38 used for that purpose is the heat medium flow supplying means referred to in the gist of the present application, that is, the heat medium 37 from the inflow port 35 to the sealed container. It corresponds to a means for generating a flow of the heat medium in the closed container 31 by causing it to flow into the inside 31 and discharge from the outlet 36.

According to the knowledge of the present applicant, although depending on the configuration of the heat exchanger 39 and the circulation system, it is easy to always maintain the solar cell temperature at, for example, 60 ° C. or lower even under conditions close to practical use as a solar energy conversion device. The solar cell temperature reaches an extremely high temperature as in the conventional case, and as a result, the inconvenience that the effective conversion efficiency of the solar cell at that temperature is greatly reduced can be suppressed to a minimum in the case of the device of the present invention. it can.

Moreover, since there are no mechanical interfaces or voids that cause light loss between the heat medium 37 and the solar cell 32, other inconvenient factors may appear in return for the forced cooling. Absent. Of course, depending on the heat medium 37, or if the heat exchanger 39 for the heat medium 37 itself is configured as a cooler, it is even possible to operate the solar cell at a temperature far below the ambient temperature. It is possible.

In addition, in this embodiment, since the transparent material is used for the sealed container 31, there is no area called the incident window of the sunlight L _S as a particularly geometrically limited area, but as defined above,
The portion where the sunlight L _S is incident on the solar cell inside the container so that it can be irradiated can be regarded as an incident window in an optical sense.

However, as seen in the third and fourth illustrated embodiments described later,
Also in the case of the first and second illustrated embodiments, even if the container portion above the surface of the solar cell 32 is left transparent, the inner wall surface of the portion below the solar cell 32 has, for example, a suitable reflective coating 41. In the case where a mark is added, the uncoated portion can be defined as an entrance window.

On the contrary, of course, the sealed container 31 is mainly a suitable metal,
It is made of resin or other opaque material suitable for maintaining the rigidity of the container, and there is a region surrounded by a window frame-shaped part by fitting glass or transparent resin to it. The solar cell 32 built in the sealed container 31 may be irradiated with the sunlight L _S through the window that is an entrance window of L _S and is also present in the mechanical sense. This also applies to each of the examples described later.

However, in FIG. 1, it is assumed that the flow of the heat transfer medium is based on the case of following the most basic idea or configuration of the present invention as described above.
In addition to the configuration in which the solar cell 32 is forcibly cooled by 37,
If necessary, wavelength conversion is performed on the light component in the wavelength region that is a relatively low sensitivity region for the solar cell 32 even in the sunlight L _S , and the wavelength component of the relatively high sensitivity region is generated for the solar cell. Therefore, the supply unit 40 for supplying an appropriate amount of the fluorescent particles ni into the heat medium 37 is also schematically shown.

Regardless of the specific mechanical configuration of the supply unit 40 itself, the point is that a predetermined amount of fluorescent particles ni can be charged and dissolved in the heat medium 37 as needed, and the heat medium flow path can be simply described. It is possible to provide a branch portion 45 with a stopper 46 in the pipe 44 that constitutes the above, and remove the stopper 46 when necessary and drop the fluorescent particles ni from it, but in the case of the illustration, a dark room type storage is further provided. Department
43 and a cock 41 that can normally rotate the valve part that normally closes the bottom of the storage part 43 by half rotation are also illustrated, and the fluorescent particles ni in the storage part 43 are normally placed in the valve part. Since the recess 42 for holding a fixed amount is provided, when the cock 41 is half-turned when necessary, the valve portion also rotates in conjunction with the cock 41, and only the predetermined amount of fluorescent particles ni contained in the recess 42, The heat medium 37 is introduced into the pipe 44, which is the main flow path, through the branch portion 45.

In this way, when the fluorescent particles ni are mixed or dissolved in the heat transfer medium flowing in the sealed container 31, the sealed container 31
Among the solar light components incident on the solar cell 32 through the incident window of, the components of the wavelength band belonging to the relatively low sensitivity region for the solar cell 32 are wavelength-converted by the fluorescent particles ni, and relatively high. It can be converted into light in a wavelength band that can exhibit sensitivity.

For example, as mentioned earlier, the solar cells that have been developed so far, regardless of whether they are crystalline, amorphous, or compound semiconductor, have wavelengths longer than 5500Å, especially from 6000Å.
It has a high-sensitivity region in the range of about 7,000Å, but sunlight also contains a sufficient amount of light components in the shorter wavelength band.

Therefore, a fluorescent substance suitable as the fluorescent particles ni, for example, C ₂₈ H ₃₁ called Rhodamine B or Rhodamine 6G under the trade name
When N ₂ O ₃ Cl is selected, this substance is mainly green (5500Å)
It is used for this device because it absorbs energy of shorter wavelength as excitation energy and emits light of wavelength less than that, that is, light of wavelength around 6000Å which belongs to wavelength range of green to red of longer wavelength than that. It is one of the most suitable fluorescent particles ni.

Of course, the above is an example, and ZnCdS / Ag (SrMgB
a) Mixed fluorescent substances such as ₃ (PO ₄ ) ₂ / Sn, MgGaO ₄ / Mn, etc., wavelength conversion efficiency, conversion wavelength band, chemical stability, easiness of handling, cost, etc. In view of the various conditions required by the above, the most suitable one may be selected from the various fluorescent substances at that time.

Further, the fluorescent particles ni to be dissolved or mixed in the heat medium 37 are not limited to one kind. If necessary, by using a plurality of types in a combination that does not cause interference or adverse reaction with each other, it is possible to utilize solar energy in a wider wavelength range.

However, in general, when the fluorescent particles ni are mixed in the heat medium 37,
Note that the concentration cannot be too high. At high concentrations, problems such as re-absorption between fluorescent particles also occur, so in practice 0.001% in mass concentration
From about 0.1% will be appropriate.

In any case, if the fluorescent particles ni are further used in the first illustrated apparatus system as described above, the substantial photoelectric conversion efficiency of the solar cell 32 is maintained at a high value in the form of forced cooling by the heat medium 37. , Among solar components, the solar cell 32 also has a component in a wavelength band in which the solar cell has relatively low sensitivity.
Can contribute to photoelectric conversion by 32,
The effective photoelectric conversion efficiency can be increased.

Moreover, even though the fluorescent particles ni are used as described above, the maintenance and management of the present apparatus are easy. As described above, in the conventional method shown in FIG. 5 in which the fluorescent particles are confined in the solid member, when the fluorescent particles that are severely deteriorated with time deteriorate, a transparent plate that confine the fluorescent particles,
As a result, the solar cell had to be replaced with a new one, but the device of the present invention can be supplemented in the simplest manner by newly supplying a predetermined amount of fluorescent particles ni from the storage section 43.

Furthermore, even if it is necessary to remove the deteriorated fluorescent particles ni, it is only necessary to replace the heat medium 37, and this work is not so difficult with the technique of handling this kind of fluid, and further, it is necessary. For example, since the flow of the heat medium 37 can be performed continuously without stopping, the work can be performed with the operating state of the system using the device of the present invention maintained.

In addition, an optical interface or a void as in the conventional structure does not occur between the portion holding the fluorescent particles ni and the solar cell, and light loss due to them does not occur.

Although the case where the device 30 shown in FIG. 1 is basically used as a photoelectric conversion device for solar energy has been described above, FIG. 1 also shows that the device 30 can be used as a photothermal conversion device. There is.

The heat medium 37 that forcibly cools the solar cell 32 itself acts as a heat collecting medium that carries solar energy as heat. Therefore, if the heat exchanger 39 provided for cooling the heat medium 37 is used as a more positive member and a device for heating another object, it is possible to use a hot water system or a power generation system, and finally It is possible to construct a system that electrically emits electric energy.

Since such a hot water system and a power generation system are already known as a single unit, their mechanism is
Although it is extremely easy for a person skilled in the art to configure using the heat exchanger 39 of 30, the present solar energy conversion device 30 eventually has both a photoelectric conversion function and a photothermal conversion function at the same time. This is a very rational hybrid type device that can be operated, and in addition to the hybrid type device having the conventional structure shown in FIG. 6, all the above-mentioned drawbacks of the conventional example can be expelled.

The means for fixing and supporting the solar cell 32 in the hermetically sealed container 31 itself is not directly specified by the present invention, but is preferable as a part of the fixing device. The effective members are well shown in FIGS. 1 and 2, and particularly in FIG. 2 (D).

That is, the solar cell 32 is attached to a support plate 47 that supports the solar cell 32 from several points in the longitudinal direction from below.

The support plate 47 has an opening 48 which allows the heat medium 37 to flow therethrough. However, since a large turbulent flow is intentionally generated in the heat medium flow 37 passing through the opening 48, in this case, the support plate The tongue piece portion 49 is provided on the 47 and projects obliquely upward from the lower edge of the opening.

That is, since the tongue piece portion 49 is provided, sufficient turbulence occurs in the heat medium 37 flowing in the sealed container 31, as schematically shown by the arrow 37 in FIG. 2 (A), This exerts a function of uniformly cooling the solar cell 32 and promotes its efficiency. As described above, when the present device 30 is used as a hybrid device, the adoption of such a heat medium turbulence promoting means 49 improves the efficiency in applying the heat energy of sunlight to the heat medium 37. To succeed.

However, it is self-evident that the mechanical and geometrical shape of the heat medium turbulent flow promoting means 49 is not limited to the above-mentioned tongue shape and can be arbitrarily designed.

As described above, in the solar energy conversion device 30 of the present invention described variously with respect to the basic structure, a plurality of solar energy conversion devices 30 are provided in the outer case 50 in which a suitable heat insulating material 51 is included inside the wall surface portion as shown in the third drawing. It can be put to practical use in the form of juxtaposition. However, as described in the arrow (arrow mark and arrow mark) indicating the flow direction of the heat medium 37 in the figure, the heat medium 37 flows in a plurality of sealed containers 31 in sequence. You can also go.

That is, the heat medium 37 that has flowed from the far side to the front side in the sealed container 31 at the rightmost end in the figure passes through the U-shaped connecting portion (not shown) from the outlet of the container. After entering the inflow port of the sealed container of left phosphorus and flowing in the container in the direction orthogonal to the drawing sheet from the front side to the back, exit the outflow port of the second sealed container from the right again, By adopting a reciprocating structure in which the phosphorus flows further into the inlet of the left phosphorus sealed container via a U-shaped connection portion, etc., all of these sealed containers 31, ...・ Can be inserted in series.

However, in this way, this is desirable when constructing a hybrid device in which the heat medium 37 itself is heated and the amount of heat thereof is effectively extracted, but the function required for the heat medium 37 is to force the solar cell 32 to operate. When mainly cooling or forced cooling is used, multiple sealed containers 31, ...
In some cases, it may be desirable to flow the heat medium 37 in parallel. This is because it is possible to better suppress the temperature rise of each solar cell 32 in each container and make it more uniform.

Therefore, in this case, the heat medium flow 37 sent from the pump portion 38 (FIG. 1) side is branched by using an appropriate branch pipe structure, and is made to flow in each sealed container 31 ,. After that, the respective outlets may be integrated again into a single pipe by the mixing pipe structure and sent back to the pump section side.

In the structure shown in FIG. 3, the wall surface portion of the sealed container where the sunlight L _S does not enter is effectively used and further contributes to the improvement of conversion efficiency. Therefore, a thin metal thin film, etc. is chemically and physically stable and has high heat resistance on the inner wall surface where the sunlight L _S does not enter.
Reflective coating using a material with as high a reflection efficiency as possible
41 has been given. This idea is based on the case 50
It can also be applied to the inner wall surface of.

In contrast to such an embodiment, looking at the embodiment shown in FIG. 4, which is shown as an embodiment including further external elements, here, it is respectively supported by the rotary support shaft 52 so that the angle can be adjusted. A plurality of reflector segments 53, ... Are used to reflect the sunlight L _S incident on itself and efficiently enter the sunlight energy conversion device 30 with respect to a horizontal plane or a reference plane. , Each is angled to a predetermined angle.

However, in the case of this embodiment, since the sunlight L _S coming from above is reflected and directed upward again, the present solar energy conversion device 30 has a lower part of the hermetically sealed container 30. It should be the entrance window of sunlight L _S , and the upper part contains a heat insulating material 51. In this case, a semi-cylindrical outer case 50
It is surrounded by. Similar to the third illustrated embodiment described above, also in this embodiment, it is possible to develop a structure in which a plurality of hermetically sealed containers 31 are arranged side by side, and the inner wall surface of the hermetically sealed container in the portion surrounded by the outer case 50 has a reflective coating. You can add 41.

Further, in the case shown in the drawing, the opening of the outer case 50 is opened in a horn shape or a trumpet shape so that the reflected light of the sunlight L _S can be easily incident on the hermetically-sealed container 31. If the coating 54 is attached, it is possible to reflect the light that has entered the surface portion 54 without incident on the sealed container 31 and then to enter the sealed container 31. In the end, such various delicate consideration is given. Will increase the overall solar energy conversion efficiency of the system.

Of course, other condensing means, for example, a condensing lens may be adopted, and the device 30, the reflecting mirror segment 53, and the condensing lens system are used for the movement of the sun in accordance with the known existing solar light tracking method. It may be movable together.

[Effect] According to the invention described in claim 1 of the present application, the heat medium flow is generated in the same hermetically sealed container that houses the solar cell, so that the solar cell is forcibly cooled very efficiently,
Moreover, since the structure does not require a boundary surface or a gap between the heat medium and the solar cell, it is possible to provide a sufficiently high efficiency solar energy conversion device for practical use.

Since the entire structure of the device can be simplified and the element used for forced cooling is also a heat transfer medium, it is easy to obtain and handle, and a pollution-free one can be selected.

Furthermore, the heat transfer stream also keeps the incident light surface of the solar cell and the inner surface of the window provided in the closed container continuously clean, so that it is convenient to suppress the secular change of the solar light transmission efficiency and the solar cell incident efficiency. To be

In addition to such a basic effect, when the heat medium turbulent flow promoting means is provided according to the invention described in claim 2, the solar cell is uniformly cooled, and the cooling efficiency, and further the photoelectric conversion efficiency is further enhanced.

Further, according to the configuration of claim 3 of the present application, when at least one or more fluorescent particles are mixed or dissolved in the heat transfer medium, the utilization efficiency in view of the wavelength band of sunlight is increased, and in that case. Also in this case, since the fluorescent particles are mixed or dissolved in the heat medium which is a fluid, the maintenance and management thereof are extremely easy, and there is no waste of having to replace even a member which is not bad. It is not difficult but rather easy as a work to additionally supply fluorescent particles to the heat medium flow or replace the whole heat medium.

Furthermore, since the heat medium used for cooling the solar cell can be used as a heat collecting medium for solar energy itself,
According to claim 4 of the present application, it is possible to provide a hybrid-type solar energy conversion device having both photoelectric conversion and photothermal conversion. By doing so, the relative solar energy utilization efficiency can be made extremely high. it can.

Therefore, no matter what is placed, it is excellent in that it does not pollute the atmospheric environment at all, and in the future, it will be used for this type of solar energy conversion device system that should be widely adopted on a global scale. There is no doubt that the invention will be a big help.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a basic embodiment of a solar energy conversion device configured according to the present invention, FIG. 2 (A) is a vertical sectional view of the first illustrated device, and FIG. 2 (B) is 1 is a horizontal sectional view of the illustrated apparatus, FIG. 2 (C) is a sectional view taken along the sectional line CC in FIG. 2 (A), and FIG. 2 (D) is a structural example of the heat medium turbulent flow promoting means. FIG. 3 is a schematic configuration diagram in a practical embodiment of the solar energy conversion apparatus of the present invention, and FIG. 4 is a practical further embodiment of the solar energy conversion apparatus of the present invention. FIG. 5 is a schematic configuration diagram, FIG. 5 is an explanatory diagram of a conventional example of a photoelectric conversion device having a wavelength conversion function using fluorescent particles, and FIG. 6 is an explanatory diagram of a conventional example in which photothermal conversion is also possible in addition to photoelectric conversion. is there. In the figure, 30 is a solar energy conversion device according to the present invention as a whole, 31 is a sealed container, 32 is a solar cell, 37 is a heat medium or a heat medium flow, 38 is a pump unit, 39 is a heat exchanger, 40 is fluorescent. A particle supply unit, 41 and 54 are reflective coatings, 49 is a heat medium turbulent flow promoting means exemplified as a tongue portion, 50 is an outer case, and 53 is a reflector segment.

Claims (4)

[Claims] 1. A hermetically sealed container having a window through which sunlight can enter, at least in part; for allowing a heat medium, which is a fluid of a material that can transmit sunlight, to flow into the hermetically sealed container. And an outlet for discharging from the sealed container; causing the heat medium to flow into the sealed container through the inlet.
A heat medium flow supply means for generating a heat medium flow in the closed container by discharging the heat medium from the outlet, the heat medium being in the closed container, being thermally coupled to the heat medium flow, and being incident through the window. A solar energy conversion device comprising: a solar cell provided at a position exposed to the incoming sunlight. 2. A heat medium turbulence having a shape that disturbs the direction of the heat medium flow flowing from the inflow port toward the outflow port to cause an appropriate turbulent flow in the heat medium flow flowing in the sealed container. It has a flow promotion means; The solar energy conversion device of Claim 1 characterized by these. 3. In the heat medium flow flowing in the hermetically sealed container, at least a part of the wavelength range deviating from the relative high sensitivity range of the solar cell in the wavelength range of sunlight is used as the relative range. The one or more types of fluorescent particles that convert to a wavelength in a high sensitivity region are mixed therein; The solar energy conversion device according to claim 1 or 2, wherein: 4. A heat exchanger for extracting the amount of heat collected by the heat collecting medium is provided outside the sealed container in order to utilize the heat medium flow flowing in the sealed container as a heat collecting medium. In addition to the photoelectric conversion function according to 1., the solar energy conversion device according to any one of claims (1) to (3).