JP2005321123A - Solar system and its operating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar system utilizing solar heat for compatibly improving the efficiency and reducing operating cost while improving maintenance property. <P>SOLUTION: The solar system comprises a heat collecting cycle which comprises a solar heat collecting part 1 having a solar battery panel 2 installed on the surface and a first heat medium stored therein for storing collected heat such as solar heat and exhaust heat from the solar battery panel 2, a circulation pump 3 for circulating the first heating medium via the solar heat collecting part 1, a control valve 4, and a heat exchanger 5 for heat exchanging the heat stored in the first heating medium with a second heating medium, and a heat pump cycle which consists of a heat exchanger 5 for evaporating refrigerant of the second heating medium with the heat stored in the first heating medium, a compressor 6, an expansion valve 7, and a radiator 8. Solar heat is stored in the first heating medium in the daytime and the first heating medium is circulated in the nighttime when an electric utility rate is lower for evaporating the refrigerant with the heat stored therein, thus improving the efficiency of the heat pump cycle and reducing operating cost. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a solar system using solar heat and an operation method thereof.

Conventionally, solar systems have been developed for the purpose of constructing a system that can more effectively use solar energy. As this solar system, in Patent Document 1, solar cells are arranged on the surface of the heat exchanger of the evaporator element, the temperature of the refrigerant flowing in the heat exchanger is set to a condition lower than the atmospheric temperature, and the efficiency is improved. A solar heat pump heating and cooling water heater is disclosed. FIG. 5 is a configuration diagram showing a conventional solar system described in Patent Document 1. As shown in FIG.
In the solar system shown in FIG. 5, a solar heat pump hot water supply circuit (compressor 21, first four-way valve 22, refrigerant water heat exchanger 23, first electromagnetic valve 24, first electronic expansion valve 25, hybrid collector 26, and second Two-way valve 27), solar heat pump heating circuit (compressor 21, first four-way valve 22, indoor heat exchanger means 28, second electronic expansion valve 29, first electronic expansion valve 25, hybrid collector 26, and second During the operation of the two-way valve 27), the hybrid collector 26 has a heat exchanger configuration, so that the refrigerant temperature acts below the atmospheric temperature by the operation of the first electronic expansion valve 25. As a result, the solar cell 31 The solar heat incident from a portion other than the arrangement of the solar cell, the exhaust heat of the solar cell 31, and the atmospheric heat through the fins 32 are also collected, and the obtained heat quantity is radiated to the atmosphere. Ku, everything will be utilized as a heating and hot water supply heat, as a result, system efficiency is increased. Moreover, since the solar cell 31 is cooled by the low-temperature refrigerant, the photoelectric conversion efficiency of the solar cell 31 is further increased.
Patent Document 2 discloses a solar energy utilization device having a latent heat storage material in which a heat collection module undergoes phase transition at a predetermined temperature or lower. FIG. 6 is a configuration diagram showing another conventional solar system described in Patent Document 2. As shown in FIG.
In the solar system shown in FIG. 6, the hybrid module receives solar energy, generates power in the power generation cell 35 of the power generation module, and receives the exhaust heat of the power generation cell 35 and the power generation cell 35 in the heat collection plate 36 of the heat collection module. The heat generated by the solar energy is stored in the liquid heat medium filled in the heat medium flow path 37 in the heat collection module and the latent heat storage material 38 installed on the back surface of the heat collection plate 36. For this reason, it is possible to collect heat while maintaining the temperature at which there is no risk of damaging the power generation cell 35 without reducing the power generation efficiency of the power generation cell 35 when the amount of solar radiation is high and the outside air temperature is high, such as in summer.
JP-A-5-66065 (page 2-3, FIG. 1) Japanese Patent Laid-Open No. 11-108467 (page 3-4, FIG. 1)

In the solar system in which the heat exchanger of the hybrid collector 26 acts as an evaporator of the solar heat pump heating and hot water supply circuit, the power generation efficiency is higher than that in the case where power generation is performed without cooling the solar cell 31, and at the same time, the solar cell 31 is collected from the atmosphere. Since the heat pump efficiency (COP) of the solar heat pump heating and the hot water supply circuit is also improved as compared with the case of heating, the system efficiency combining the efficiency of both is increased.
However, in this solar system, since the heat medium having a cooling function is a refrigerant and has no heat storage capability, the heat cannot be used in a time zone other than the time of heat storage such as solar heat. There was a problem that the running cost could not be reduced by storing heat using electric power and using the heat in the heat pump system.
On the other hand, in the solar system having the latent heat storage material 38 in the heat collection module, solar energy can be stored in the latent heat storage material 38, but the latent heat storage material 38 is filled in the heat collection module. There was a problem that maintenance such as replacement of the latent heat storage material 38 in which deterioration such as separation occurred was difficult. And if the heat collection module is installed on the roof, it will be a maintenance work on the roof, and it is necessary to remove the power generation module that has no problem in terms of durability. There was a problem with the maintainability of the media.

  Accordingly, an object of the present invention is to solve the above-described conventional problems, and to provide a solar system having a low running cost and excellent maintainability, and an operation method thereof.

The solar system according to the first aspect of the present invention includes a solar heat collecting part that collects solar heat or the like in a built-in first heat medium and stores the heat, and the first heat medium and the second heat medium. A heat exchanger for performing heat exchange, wherein the circulating power of the first heat medium in a predetermined time zone is greater than the circulating power of the first heat medium in a time zone other than the predetermined time zone. To do.
According to a second aspect of the present invention, in the solar system according to the first aspect, the first heat medium contains a substance that undergoes a phase change at a temperature equal to or lower than a maximum temperature reached by the solar heat collecting part, and the substance In any state, the first heat medium has fluidity.
According to a third aspect of the present invention, in the solar system according to the second aspect, the first heat medium contains a plurality of the substances having different phase change temperatures.
According to a fourth aspect of the present invention, in the solar system according to the second or third aspect, the substance is a material that changes phase from a solid phase to a liquid phase when receiving heat.
The present invention according to claim 5 is the solar system according to claim 2, wherein the substance is dispersed in a medium.
According to a sixth aspect of the present invention, in the solar system according to the fifth aspect, the substance has a density smaller than that of the medium in either a solid phase or a liquid phase.
According to a seventh aspect of the present invention, in the solar system according to the fifth aspect, the solar heat collecting part has a two-layer structure of a first layer and a second layer, and the first layer is adjacent to a solar cell panel. Providing a content rate adjusting means for separating the first heat medium into a low content rate heat medium and a high content rate heat medium having different content rates of the substance, and providing the low content rate heat medium in the first layer. Storing, and storing the high content heat medium in the second layer.
The present invention according to claim 8 is the solar system according to claim 5, wherein a storage container for separating and storing a part of the first heat medium is different from a content ratio of the substance in the first heat medium. A content rate adjusting means for separating the low content rate heat medium and the high content rate heat medium is provided, the low content rate heat medium is stored in the storage container, and the high content rate heat is stored in the solar heat collecting part. It is characterized by storing a medium.
The present invention according to claim 9 is the solar system according to claims 1 to 6 and 8, wherein a solar cell panel is installed on a surface of the solar heat collecting section.
According to a tenth aspect of the present invention, in the solar system according to any one of the first to ninth aspects, a refrigerant is used as the second heat medium, and the heat exchanger is an evaporator of a heat pump cycle. It is characterized by.
The solar system operating method according to claim 11 is the solar system according to any one of claims 1 to 10, wherein the first heat medium is circulated in a time zone other than the predetermined time zone. It is characterized by stopping.
A solar system operating method according to a twelfth aspect of the present invention is the solar system according to any one of the first to tenth aspects, wherein at least the first heat medium is used in a time zone other than the predetermined time zone. It is characterized by circulating a part.
A solar system operating method according to a thirteenth aspect of the present invention is the solar system according to any one of the first to tenth aspects, wherein the first heat medium is supplied in the predetermined time zone where the power rate is low. It is characterized by circulation.

  According to the solar system and the operation method thereof of the present invention, low running cost and good maintainability can be realized.

In the solar system according to the first embodiment of the present invention, the circulating power of the first heat medium in a predetermined time zone is larger than the circulating power of the first heat medium in a time zone other than the predetermined time zone. According to the present embodiment, for example, by circulation of the first heat medium in a predetermined time zone at night, it becomes possible to use the heat storage of the first heat medium at night, reducing the running cost, The first heat medium can be recovered from the roof, for example, by the circulation, and the maintainability of the heat medium can be improved.
In the solar system according to the first embodiment, the second embodiment of the present invention contains, in the first heat medium, a substance that undergoes a phase change at a temperature equal to or lower than the maximum temperature reached by the solar heat collector, The first heat medium has fluidity in any state of the substance. According to the present embodiment, the heat capacity of the first heat medium is increased, and the heat storage characteristics in the solar heat collecting section are improved.
According to the third embodiment of the present invention, in the solar system according to the second embodiment, the first heat medium contains a plurality of substances having different phase change temperatures. According to the present embodiment, for example, responsiveness to changes in the outside air temperature due to the season is improved.
The fourth embodiment of the present invention is a solar system according to the second or third embodiment, wherein the substance is a material that changes phase from a solid phase to a liquid phase upon receiving heat. According to the present embodiment, the change from the solid phase to the liquid phase in the solar heat collecting section has a small volume change and reduces pressure fluctuation and flow resistance, so the volume of the solar heat collecting section is reduced. be able to.
The fifth embodiment of the present invention is a solar system according to the second embodiment in which a substance is dispersed in a medium. According to the present embodiment, the heat transfer characteristics of the first heat medium are made uniform, and the heat transfer efficiency is improved.
In the sixth embodiment of the present invention, in the solar system according to the fifth embodiment, the substance has a density smaller than that of the medium in either the solid phase or the liquid phase. According to the present embodiment, natural convection of the first heat medium is generated in the solar heat collector, and the heat transfer efficiency in the solar heat collector is improved.
According to a seventh embodiment of the present invention, in the solar system according to the fifth embodiment, the solar heat collecting part has a two-layer structure of a first layer and a second layer, and the first layer is adjacent to the solar cell panel. Providing a content rate adjusting means for separating the first heat medium into a low content rate heat medium and a high content rate heat medium having different substance contents, and storing the low content rate heat medium in the first layer; A high content heat medium is stored in the second layer. According to the present embodiment, natural convection of the first heat medium is generated in the solar heat collector, and the heat transfer efficiency in the solar heat collector is improved.
In the solar system according to the fifth embodiment, the eighth embodiment of the present invention is different from the storage container that separates and stores a part of the first heat medium in the solar system according to the fifth embodiment, and the content ratio of the first heat medium is different. A content rate adjusting means for separating the low content rate heat medium and the high content rate heat medium is provided, the low content rate heat medium is stored in the storage container, and the high content rate heat medium is stored in the solar heat collecting part. Is. According to this Embodiment, the weight of the heat medium stored in a solar heat collecting part can be reduced, and the load to the house by installation of a solar heat collecting part can be reduced.
The ninth embodiment of the present invention is a solar system according to the first to sixth and eighth embodiments, in which a solar cell panel is installed on the surface of the solar heat collecting section. According to the present embodiment, the power generation efficiency is improved by lowering the temperature of the solar cell panel, and the running cost can be reduced.
In the solar system according to the first to ninth embodiments, the tenth embodiment of the present invention uses a refrigerant as the second heat medium and the heat exchanger is an evaporator of a heat pump cycle. According to the present embodiment, the heat pump efficiency can be improved and the running cost can be reduced.
In the solar system operating method according to the eleventh embodiment of the present invention, in the solar system according to the first to tenth embodiments, the circulation of the first heat medium is stopped in a time zone other than the predetermined time zone. Is. According to this embodiment, since no electric power or the like is used for circulation of the first heat medium, the running cost can be further reduced.
The solar system operating method according to the twelfth embodiment of the present invention is the solar system according to the first to tenth embodiments, wherein at least a part of the first heat medium is applied in a time zone other than the predetermined time zone. It circulates. According to the present embodiment, it is possible to reduce the running cost and improve the power generation efficiency by lowering the temperature of the solar cell panel by natural circulation of the first heat medium.
In the solar system operating method according to the thirteenth embodiment of the present invention, in the solar system according to the first to tenth embodiments, the first heat medium is circulated in a predetermined time zone where the power rate is low. It is. According to the present embodiment, the running cost can be further reduced.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a configuration diagram of a solar system in a first embodiment of the present invention.
The solar system of the present embodiment shown in FIG. 1 includes a heat collection cycle, a heat pump cycle, and hot water supply means. The heat collection cycle in which the first heat medium circulates is the first heat in which the solar cell panel 2 is installed on the surface, and the solar heat, exhaust heat from the solar cell panel 2 and the like are collected and stored therein. A solar heat collecting section 1 for storing heat in the medium, a control valve 4 for controlling the flow of the first heat medium, a heat exchanger 5 for exchanging heat stored in the first heat medium to the second heat medium, and solar heat The circulation pump 3 is configured to circulate the first heat medium via the heat collector 1 and the like.
The heat pump cycle in which the second heat medium circulates includes a heat exchanger 5 that collects heat in the solar heat collecting unit 1 and evaporates the refrigerant as the second heat medium with the heat stored in the first heat medium; The compressor 6, the radiator 8, and the expansion valve 7 are included. Furthermore, the hot water supply means includes a radiator 8 that heats hot water and a heat storage tank 9 that stores the heated hot water.
Here, a crystalline silicon solar cell is used as the solar cell panel 2, and minute capsules filled with a phase change material (for example, octadecane) that changes phase between a solid phase and a liquid phase at a predetermined temperature as a first heat medium are dispersed in water. The slurry (for example, carbon dioxide) is used as the slurry and the second heat medium. In addition, the said predetermined temperature is the temperature within the heat collection temperature range of the solar heat collection part 1, in other words, the temperature below the maximum temperature which the solar heat collection part 1 reaches | attains.

Next, operation | movement of the solar system of a present Example is demonstrated. The operation of the solar system employs a power charge system in which the electricity charge in the midnight hours is cheaper than the daytime.
First, during the daytime period, the slurry is stored in the solar heat collecting section 1 with the circulation pump 3 stopped and the control valve 4 closed. The solar radiation energy from the sun is partly converted into electric power by the solar cell panel 2, and part is collected by the slurry in the solar heat collector 1. Here, the collected solar heat or the like is stored by changing the phase change material in the slurry from solid to liquid. On the other hand, the output power in the solar cell panel 2 is converted from direct current to alternating current by an inverter (not shown), and can be connected to another power system for sale.
Subsequently, when the power charge is lower than the daytime time zone, the control valve 4 is opened, the circulation pump 3 is operated, and the slurry circulation is started. At the same time, when the operation of the heat pump cycle is started, the refrigerant depressurized by the expansion valve 7 absorbs and evaporates from the slurry that collects solar heat in the daytime time zone in the heat exchanger 5 and becomes high temperature and high pressure in the compressor 6. Heat is dissipated by the radiator 8 to heat the hot water supply water. Here, in the heat storage of the phase change material, the phase change material in the slurry undergoes a phase change from a liquid to a solid and is used for evaporation of the refrigerant.
On the other hand, the heated hot water is stored in the heat storage tank 9. At this time, the operation of the circulation pump 3 is stopped when the heat storage amount in the heat storage tank 9 becomes equal to or greater than a predetermined heat amount, and the slurry is stored again in the solar heat collecting unit 1 with the control valve 4 closed.

Due to the configuration of the solar system of the present embodiment, the heat capacity (capacity capable of absorbing heat) is increased by the amount of slurry stored in the solar heat collector 1 and the solar heat collector 1 in the daytime period. Since the temperature of the solar cell panel 2 at this time is lower than when the solar cell panel 2 is installed alone, the power generation efficiency is increased. In addition, since the amount of power generation increased with this is all sold during the daytime hours, and the equivalent amount is generated as income, an effect of reducing utility costs can be obtained.
In addition, during the midnight hours, the heat pump cycle is operated alone by operating the heat pump cycle using the slurry that collects solar heat higher than the outside air temperature during the day as the heat sink (the heat radiation source for the refrigerant). Since the heat pump efficiency (COP) is improved more than the case, an effect of reducing the utility cost can be obtained.
Thus, the circulation of the slurry is stopped in the daytime (or a minute amount of the slurry is circulated) and heat is stored in the slurry, and the heat storage can be used by circulating the slurry at night. The solar system's heat collection cycle configuration and its operating method can both improve efficiency and reduce utility costs.
That is, when the heat pump cycle is operated simultaneously with the power generation in the solar cell panel 2 during the daytime period as in the past, the efficiency is improved as compared with the case where the solar cell panel 2 and the heat pump cycle are installed individually, Since the price difference between the daytime hours and the midnight hours cannot be used, the problem of increased utility costs can be solved, and the running cost of the solar system can be further reduced.
Furthermore, in the configuration of the present embodiment, maintainability can be improved by allowing the slurry to circulate. That is, in order to obtain the same power generation efficiency improvement effect as the present configuration, in the conventional configuration in which the phase change material is installed on the back surface of the solar cell panel 2, the maintenance of the phase change material was substantially impossible. In this embodiment, the phase change material in the slurry can be obtained by circulation, so that the replacement work of the deteriorated phase change material or the like is not performed on the roof, and the solar battery panel 2 The solar system can be easily maintained without removing the battery.

In the present embodiment, the circulation pump 3 is stopped in the daytime to completely stop the circulation of the slurry. However, within the input range corresponding to the power generation amount increased by lowering the temperature of the solar cell panel 2. If so, the same effect as described above can be obtained even when the slurry is circulated at a minute flow rate without being completely stopped. Moreover, if this slurry micro quantity circulation structure is used, since the forced convection of a slurry is formed in the solar heat collecting part 1, the heat collection efficiency to a slurry (namely, phase change material) rises, and the solar cell panel 2 As a result, the power generation efficiency is also increased.
In the present embodiment, the box-shaped solar heat collecting section 1 is installed on the back surface of the solar cell panel 2, but the present invention is not necessarily limited to this, and any shape may be used. The solar heat collecting section 1 may be configured to have a space capable of storing a slurry capable of storing the necessary heat collection amount, and the same effects as described above can be obtained.
In addition, any method such as brazing, welding, pressure bonding means such as roll bonding, etc. may be used as a method of manufacturing the solar heat collecting section 1, and the phase change between the solid phase and the liquid phase of the phase change material is used. Therefore, since the volume change and pressure increase inside the solar heat collecting part 1 are extremely small, it is possible to manufacture by a simple method. For example, in the case where the solar heat collecting unit 1 is made of a material having a large heat capacity such as roof tiles and is a building material integrated type, the first heat medium such as slurry is not necessarily stored in the solar heat collecting unit 1. Also, the same effect as described above can be obtained. This building material integrated type has a configuration that can be easily realized, and has an effect that an increase in initial cost is small as compared with the case where the solar heat collecting unit 1 is separately installed in addition to roof tiles and the like.

Moreover, although the slurry which disperse | distributed what filled the phase-change material into the microcapsule in water is used as a 1st heat medium of a present Example, it is not necessarily limited to this.
Although octadecane is used as the phase change material, it may be a substance using sodium sulfate decahydrate, calcium chloride hexahydrate or the like, and the melting point and heat of fusion depending on the system configuration and the type of the second heat medium. Judging from the above, the substance can be selected.
In addition, the phase change material may be dispersed in the medium as it is without being encapsulated, and the medium is not limited to water. If the density is adjusted and there is no problem with the solubility of the phase change material, it is not necessary. The medium may be used. With the configuration of the first heat medium in which the phase-changing substance is dispersed in the medium, the heat transfer characteristics of the first heat medium are made uniform, that is, the heat transfer efficiency in the solar heat collecting section is increased, and the running cost is reduced. Can lead to a reduction.
Further, although octadecane is used alone as the phase change material, for example, phase change materials having different melting points such as hexadecane may be mixed with octadecane and used. That is, the first heat medium may include a plurality of phase-changing substances having different phase change temperatures. The solar cell panel 2 is caused by the octadecane phase change in the summer and the hexadecane phase change in the winter. Temperature rise is suppressed, and the effect of improving the response to changes in the outside air temperature for each season is obtained.

Even if water, antifreeze, oil, or the like is used alone as the first heat medium instead of a slurry made of a phase change material or the like, the same effect as described above can be obtained. However, the lowering of the temperature of the solar battery panel 2 is more effective as the heat capacity of the first heat medium is larger. Therefore, the first heat medium causes a phase change within the heat collection temperature range of the solar heat collection unit 1. If it contains, a greater effect can be obtained. Furthermore, in order to prevent the solar heat collecting part 1 that is often installed on the roof from becoming large in terms of securing volume and pressure resistance, the phase change is performed between the solid phase and the liquid phase. It is preferable.
Moreover, although the crystalline silicon solar cell is used as the solar cell panel 2, it is not necessarily limited thereto, and a thin film silicon solar cell such as amorphous silicon or a compound solar cell such as CIS may be used. If the power generation efficiency of the solar cell panel 2 has temperature dependence, the same effect as described above can be obtained.
Furthermore, it is not always necessary to install the solar battery panel 2, and even when only the solar heat collector 1 is installed and the heat storage of the slurry is used for the heat pump cycle, compared to the case where the heat pump cycle is installed alone, In the same manner as described above, the effects of reducing utility costs and improving maintainability can be obtained.

In this embodiment, carbon dioxide is used as the refrigerant of the heat pump cycle. However, the present invention is not necessarily limited thereto, and the same effect as in the above embodiment can be obtained even if a refrigerant such as HFC is used. It is. However, when carbon dioxide is used as the refrigerant, the refrigerant may reach a supercritical state within the heat collection temperature range in the solar heat collecting section 1, and therefore the opening of the expansion valve 7 during the heat pump cycle operation. Need to be controlled.
In the present embodiment, the first heat medium is circulated, and the heat storage source is transmitted to the refrigerant of the second heat medium by the heat exchanger 5 and used as the evaporation heat source of the heat pump cycle. The first heat medium stored in the solar heat collector 1 is circulated using the inexpensive solar energy, and is stored and used as it is (for example, hot water supply or heating system), or After the first heating medium is heated with an electric heater or the like and further stored, a configuration or method for storing and using the first heating medium may be used. ) And the effect of improving the maintainability.
Furthermore, although the heat source output from the heat radiator 8 of the heat pump cycle is used for heating water for hot water supply, the heat source is not necessarily limited to this, and is based on a heat source for heating, an absorption type, and an adsorption type heat pump. It is good also as a structure utilized as a heat source for air_conditioning | cooling, and the same effect as the above is acquired.

The solar system of the second embodiment has the same basic configuration as that of the first embodiment, but the density of the phase change material in the slurry is smaller than that of water in either the solid phase or the liquid phase. The point of using materials is different, and this point will be mainly described.
FIG. 2 is a diagram illustrating the configuration of the solar heat collecting section of the solar system and the slurry flow in the solar system according to the second embodiment of the present invention.
In the solar system of the present embodiment shown in FIG. 2, by using a phase change material having a density lower than that of water for the slurry as the first heat medium in the heat collection system of the first embodiment, The high content slurry 10 having a high content of the phase change material and the low content slurry 11 having a low content are separated and stored in the solar heat collecting section 1.

Next, operation | movement of the solar system of a present Example is demonstrated.
First, during the daytime period, the slurry is stored in the solar heat collecting section 1 with the circulation pump 3 stopped and the control valve 4 closed. The solar radiation energy from the sun is partly converted into electric power by the solar cell panel 2, and part is collected by the slurry in the solar heat collector 1. At this time, due to the density difference between the phase change material (for example, using octadecane) and water, a high content slurry 10 having a high content of the phase change material is gathered upward in FIG.
Thereby, the upper part of the heat capacity of the solar heat collecting part 1 and the slurry is larger in the upper part, and therefore, the upper part of the solar cell panel 2 is cooler than the lower part.
On the other hand, the low content slurry 11 having a low content of the phase change material gathering downward is heated on the surface in contact with the solar cell panel 2 to form an upward flow, and the high content slurry 10 on the upper side. , The heat is taken away and cooled, and a downward flow is formed along the surface not in contact with the solar cell panel 2. From the above, a circulating flow (arrow flow shown) is formed in the solar heat collecting section 1 by natural convection of the slurry.

In the configuration of the solar system of this embodiment, the heat collection efficiency in the solar heat collecting section 1 is increased by convective heat transfer, and power is not used to improve the heat collection efficiency. All the power is sold and the equivalent amount is generated as income, so the utility cost can be reduced.
Further, in this embodiment, there is an effect that it can be realized with a simple configuration in which only the type of the first heat medium is changed without substantially changing the system configuration of the first embodiment.

In addition, although the slurry which disperse | distributed what filled the phase change material into the microcapsule in water is used as a 1st heat medium of a present Example, it is not necessarily limited to this.
Although octadecane is used as the phase change material, it is not necessarily limited to this. Depending on the system configuration and the type of the second heat medium, the substance is selected based on the melting point, heat of fusion, and density. Just do it.
Further, the phase change material of the phase change material may be dispersed as it is in the medium without being encapsulated, and the medium is not limited to water. If there is no other medium, another medium may be used.
Furthermore, the solar cell panel 2 does not necessarily have to be installed, and even when only the solar heat collecting unit 1 is installed, as compared with the case where the heat pump cycle is installed alone, the utility cost reduction and maintainability are the same as described above. An improvement effect can be obtained.

The solar system of the third example has the same basic configuration as the first example, but the solar heat collecting part has two layers, and the content of the phase change material in the solar heat collecting part is The difference is that the slurry having a high content and the slurry having a low content are separated and stored, and this point will be mainly described.
FIG. 3 is a configuration diagram of the solar system in the third embodiment of the present invention.
In the solar system of the present embodiment shown in FIG. 3, in the heat collection system configuration of the first embodiment, a slurry (that is, a low content of phase change material disposed so as to contact the solar cell panel 2) The solar heat collector first layer 12 storing the content heat medium) and the slurry having a high content of the phase change material disposed so as to be in contact with the solar heat collector first layer 12 (ie, high content) The content of the phase change material in the slurry for adjusting the solar heat collecting part 1a composed of the solar heat collecting part second layer 13 for storing the heat medium) and the low content slurry and the high slurry is adjusted. Content rate adjusting means 14.

Next, operation | movement of the solar system of a present Example is demonstrated.
When the circulation pump 3 is operated at an inexpensive midnight time period when the power charge is low, the operation of the circulation pump 3 is stopped when the heat storage amount in the heat storage tank 9 reaches a predetermined heat amount, the control valve 4 is closed, and the slurry is It stores in the solar heat collecting part 1a. At this time, in the content rate adjusting means 14, the slurry is separated into a slurry having a high content of the phase change material and a slurry having a low content of the phase change material by membrane separation, and the low content rate slurry is separated from the solar heat collecting section. In the first layer 12, a slurry having a high content rate is divided and stored in the solar heat collecting part second layer 13.
Further, during the daytime period, the slurry is stored in the solar heat collecting part first layer 12 and the solar heat collecting part second layer 13 with the circulation pump 3 stopped and the control valve 4 closed. The solar radiation energy from the sun is partly converted into electric power by the solar cell panel 2, and part is collected by the slurry in the solar heat collecting part 1a.
At this time, the slurry having a higher content in the solar heat collector second layer 13 has a larger heat capacity than the slurry having a lower content in the solar heat collector first layer 12, so that the solar heat collector The temperature of the side 12a that is in contact with the solar cell panel 2 in the first layer 12 is higher than the temperature of the side 12b that is in contact with the second solar heat collecting part layer 13, and thus the first solar heat collecting part 1 An upward flow is formed on the side 12 a in contact with the solar cell panel 2 in the layer 12, and a downward flow is formed on the side 12 b in contact with the solar heat collecting part second layer 13. From the above, a circulating flow by the natural convection of the slurry is formed in the solar heat collecting section first layer 12.
In the configuration of the solar system of the present embodiment, the heat collection efficiency in the solar heat collecting section 1a is increased by convection heat transfer, and power is not used to form the convection to improve the efficiency. All of the generated power is sold, and a considerable amount of income is generated, so the utility cost can be reduced.

In the present embodiment, a separation method using a membrane is used as the content rate adjusting means 14, but the method is not necessarily limited to this. For example, in order to improve the heat conduction characteristics in the capsule of the phase change material A method of gathering phase change materials by adding minute energy, such as a method of separating metal fibers and the like by separating them by attracting capsules by magnetic force, can obtain the same effect as above. is there. However, the smaller the energy required for the separation, the better.
Furthermore, it is not always necessary to install the solar battery panel 2, and even when only the solar heat collecting part 1a is installed, compared to the case where the heat pump cycle is installed alone, the utility cost reduction and maintainability are the same as described above. An improvement effect can be obtained.

The solar system of the fourth embodiment has the same basic configuration as that of the first embodiment, but separates the slurry having a high phase change material content from the slurry having a low content rate, so that only the slurry having a high content rate is solar heated. It is different in that it is stored in the heat collecting part, and this point will be mainly described.
FIG. 4 is a configuration diagram of the solar system in the fourth embodiment of the present invention.
In the solar system of the present embodiment shown in FIG. 4, in the heat collection system configuration of the first embodiment, the solar heat collecting section 1 b that stores the slurry having a high content of the phase change material, and the phase change material in the slurry. The content rate adjustment means 14 which adjusts a content rate, and the low content rate slurry storage container 15 which stores the slurry with a low content rate of a phase change material are provided.

Next, operation | movement of the solar system of a present Example is demonstrated.
The circulation pump 3 is operated in the low-night time zone when the electricity rate is low, and the slurry stored in the solar heat collecting section 1b and the slurry stored in the low content slurry storage container 15 are circulated while mixing, and the heat storage in the heat storage tank 9 is performed. When the amount reaches a predetermined amount of heat, the operation is stopped, the control valve 4 is closed, and the slurry is stored in the solar heat collecting section 1b. At this time, in the content rate adjusting means 14, the slurry is separated into a slurry having a high phase change material content and a low content slurry by membrane separation, and the slurry having a high content rate is stored in the solar heat collecting section 1 b, and the content rate is low. The slurry is stored in the low content slurry storage container 15.
With the configuration of the solar system of the present embodiment, it is possible to reduce the temperature of the solar cell panel 2, so that the utility cost reduction effect associated with the improvement of power generation efficiency can be obtained as in the first to third embodiments. At the same time, the slurry weight can be suppressed by adjusting the content ratio, and the slurry weight stored on the roof can be reduced. Thereby, since the restrictions with respect to the load resistance of a house are eased, the range of the house which can apply a solar system becomes wide. It also has excellent safety when an earthquake occurs.

In the present embodiment, a separation method using a membrane is used as the content rate adjusting means 14, but the method is not necessarily limited to this. For example, in order to improve the heat conduction characteristics in the capsule of the phase change material A method of gathering phase change materials by adding minute energy, such as a method of separating metal fibers and the like by separating them by attracting capsules by magnetic force, can obtain the same effect as above. is there. However, the smaller the energy required for the separation, the better.
Furthermore, it is not always necessary to install the solar battery panel 2, and even when only the solar heat collecting part 1b is installed, compared to the case where the heat pump cycle is installed alone, the reduction of the utility cost and the maintainability as described above. An improvement effect can be obtained.

  The solar system according to the present invention has high energy efficiency, low operating costs, good maintainability, and is useful as a domestic air conditioning and heating water heater. It can also be used for industrial heating / cooling devices.

The block diagram of the solar system in 1st Example of this invention The figure showing the structure of the solar heat collecting part of the solar system in the 2nd Example of this invention, and the slurry flow in the inside The block diagram of the solar system in the 3rd Example of this invention The block diagram of the solar system in the 4th Example of this invention Configuration diagram of a conventional solar system Configuration diagram of other conventional solar systems

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b Solar heat collection part 2 Solar cell panel 3 Circulation pump 4 Control valve 5 Heat exchanger 6 Compressor 7 Expansion valve 8 Radiator 9 Heat storage tank 10 High content slurry 11 Low content slurry 12 Solar heat collection part 1st layer 12a Side in contact with solar cell panel 12b Side in contact with solar heat collecting part second layer 13 13 Solar heat collecting part second layer 14 Content rate adjusting means 15 Low content rate slurry storage container

Claims (13)

  A solar heat collecting part for collecting solar heat and the like in the first built-in heat medium to store the heat, and a heat exchanger for performing heat exchange between the first heat medium and the second heat medium, The solar system, wherein a circulating power of the first heat medium in a time zone is larger than a circulating power of the first heat medium in a time zone other than the predetermined time zone.   The first heat medium contains a substance that undergoes a phase change at a temperature equal to or lower than the maximum temperature reached by the solar heat collecting part, and the first heat medium has fluidity in any state. The solar system according to claim 1, wherein   The solar system according to claim 2, wherein the first heat medium includes a plurality of the substances having different phase change temperatures.   The solar system according to claim 2 or 3, wherein the substance is a material that changes from a solid phase to a liquid phase when receiving heat. The solar system according to claim 2, wherein the substance is dispersed in a medium.   The solar system according to claim 5, wherein the substance has a density smaller than that of the medium in either a solid phase or a liquid phase.   The solar heat collecting part has a two-layer structure of a first layer and a second layer, the first layer is provided adjacent to a solar cell panel, and the first heat medium has a low content ratio in which the contents of the substances are different. A content rate adjusting means for separating the heat medium and the high content heat medium is provided, the low content heat medium is stored in the first layer, and the high content heat medium is stored in the second layer. 6. The solar system according to claim 5, wherein the solar system is characterized.   A storage container that separates and stores a part of the first heat medium, and a content ratio that separates the first heat medium into two low-content heat media and high-content heat media that have different contents of the substance. The solar system according to claim 5, further comprising an adjusting unit, wherein the low content heat medium is stored in the storage container, and the high content heat medium is stored in the solar heat collecting unit.   The solar system according to claim 1, wherein a solar cell panel is installed on a surface of the solar heat collecting part.   The solar system according to any one of claims 1 to 9, wherein a refrigerant is used as the second heat medium, and the heat exchanger is an evaporator of a heat pump cycle.   The solar system according to any one of claims 1 to 10, wherein the circulation of the first heat medium is stopped in a time zone other than the predetermined time zone.   The solar system according to any one of claims 1 to 10, wherein at least a part of the first heat medium is circulated in a time zone other than the predetermined time zone. .   The solar system according to any one of claims 1 to 10, wherein the first heat medium is circulated in the predetermined time zone where the power rate is low.

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