JP7022487B2 - Solar power generation hot water supply system - Google Patents

Description

The present invention relates to a photovoltaic power generation hot water supply system using a photovoltaic power generation panel and a heat pump.

A power generation device using a photovoltaic power generation panel (hereinafter, “photovoltaic power generation panel”) is disclosed in, for example, Patent Document 1.
Further, a system using a photovoltaic power generation panel and a heat pump is disclosed in, for example, Patent Document 2.

In the "power generation device using solar energy" of Patent Document 1, a cooling unit having a shape substantially the same as that of the photovoltaic panel and having a flow hole inside is provided on the back side of the light receiving surface of the photovoltaic cell (photovoltaic panel). The photovoltaic panel is cooled by passing a flow cooling medium through the flow hole of the cooling unit. By this cooling, the temperature rise of the photovoltaic power generation panel is suppressed to improve the power generation efficiency.

The "solar energy utilization system" of Patent Document 2 is a heat medium between a first heat exchanger for cooling a photopower panel, a heat pump connected to the first heat exchanger, and the first heat exchanger and the heat pump. It is provided with a circulation pump that circulates the energy and a flow control unit that changes the flow rate of the circulation pump. This is aimed at improving the efficiency of solar energy utilization.

Japanese Patent Application Laid-Open No. 2003-113771 Japanese Unexamined Patent Publication No. 2013-83397

In Patent Document 1, for example, by using low temperature (20 to 30 ° C.) tap water as the flow cooling medium, it is possible to suppress the temperature rise of the photovoltaic power generation panel and improve the power generation efficiency.
However, in this case, the temperature of tap water heated by the photovoltaic panel depends on the weather, and is, for example, only 50 to 60 ° C. at the maximum. Therefore, a large hot water storage tank was indispensable to hold the required amount in the house.

In Patent Document 2, since the water supply is heated by the heat pump, hot water having a high temperature (for example, 70 to 80 ° C.) can be stored in the hot water storage tank.
However, in Patent Document 2, when water or an antifreeze liquid is used as the heat medium, this heat medium circulates between the first heat exchanger and the evaporator of the heat pump, so that the heat medium temperature after cooling by the evaporator is changed. High (eg 30-40 ° C). Therefore, the cooling capacity of the photovoltaic power generation panel is lower than that of Patent Document 1, and the power generation efficiency is also lowered accordingly.

The present invention has been devised to solve the above-mentioned problems. That is, an object of the present invention is a solar power generation hot water supply system capable of cooling a photovoltaic power generation panel to improve power generation efficiency and storing hot water at a high temperature (for example, 70 to 80 ° C.) in a hot water storage tank without an auxiliary heat source. To provide.

According to the present invention, a photovoltaic panel that generates electricity with sunlight and
A heat collecting mat attached to the back surface of the photovoltaic power generation panel, having a flow path through which water supply and circulating water flow, and cooling the photovoltaic power generation panel,
A heat pump that has a compressor, a condenser, an expander, and an evaporator, and a heat medium circulates inside.
A hot water storage tank that holds hot water inside, and
A low-temperature circulation line that circulates the circulating water between the heat collecting mat and the evaporator and cools the heat collecting mat.
A high-temperature circulation line that circulates the hot water between the hot water storage tank and the condenser and heats the hot water storage.
A water supply line that supplies the water supply to the heat collecting mat,
Provided is a photovoltaic power generation hot water supply system including a hot water storage line for supplying the water supplied heated by the heat collecting mat to the hot water storage tank or the high temperature circulation line.

According to the present invention, since the heat collecting mat has a flow path through which water supply and circulating water flow, even if the circulating water temperature for cooling is high, by using low temperature (20 to 30 ° C.) tap water as water supply, it is possible to use tap water at a low temperature (20 to 30 ° C.). The photovoltaic power generation panel can be cooled to below the circulating water temperature to improve power generation efficiency.

Further, since the water supply heated by the heat collecting mat is supplied to the hot water storage tank or the high temperature circulation line as hot water (for example, 50 to 60 ° C.) by the hot water storage line, the temperature of the hot water held in the hot water storage tank can be raised in advance. ..

Further, the heat pump uses the circulating water heated by the heat collecting mat (for example, 30 to 40 ° C.) as a heat source to heat the hot water storage (for example, 50 to 60 ° C.) circulating between the hot water storage tank and the condenser. Can be heated to high temperatures (eg 70-80 ° C) without an auxiliary heat source.

Therefore, since hot water storage at a high temperature (for example, 70 to 80 ° C.) can be stored in the hot water storage tank, the hot water storage tank for holding the required amount in the house can be miniaturized.

It is an overall conceptual diagram of the solar power generation hot water supply system by this invention. It is an overall block diagram of the solar power generation hot water supply system by this invention. It is a schematic diagram which shows the relationship between the heat transfer length and the temperature in a heat pump. It is 1st Embodiment figure of the heat collecting mat. It is a 2nd Embodiment figure of the heat collecting mat. It is a 3rd embodiment diagram of a heat collecting mat.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In addition, the same reference numerals are given to the common parts in each figure, and duplicate description is omitted.

FIG. 1 is an overall conceptual diagram of a photovoltaic power generation hot water supply system 100 according to the present invention.
In this figure, the solar power generation hot water supply system 100 includes a photovoltaic power generation panel 10, a heat collecting mat 20, a heat pump 30, and a hot water storage tank 40.

The photovoltaic power generation panel 10 generates electricity with the energy of sunlight. The obtained electric power may be supplied to the outside or may be used to drive a pump or the like constituting the solar power generation hot water supply system 100.

The heat collecting mat 20 is attached in close contact with the back surface of the photovoltaic power generation panel 10 to cool the photovoltaic power generation panel 10. This attachment may be, for example, by pasting with an adhesive.
The heat pump 30 heats the hot water storage 3 of the hot water storage tank 40 using the circulating water 2 heated by the photovoltaic power generation panel 10 as a heat source.
The hot water storage tank 40 holds the hot water storage 3 inside. The hot water storage 3 is used, for example, for use in a house (bath, kitchen, heating, etc.).

FIG. 2 is an overall configuration diagram of the photovoltaic power generation hot water supply system 100 according to the present invention.
In this figure, the heat pump 30 has a compressor 32, a condenser 34, an expander 36, and an evaporator 38, and the heat medium 4 circulates inside.
The circulation path of the heat medium 4 is shown by a → b → c → d → a in the figure. The condensation temperature TH in the condenser 34 is set to, for example, 90 to 100 ° C., and the evaporation temperature TL in the evaporator 38 is set to, for example, 30 to 40 ° C.
From a to b, the heat medium 4 is adiabatically compressed and the pressure rises from PL to PH and the steam temperature rises from TL to TH. From b to c, the heat medium 4 is isothermally cooled and liquefied at the pressure PH. From c to d, the heat medium 4 adiabatically expands and the pressure drops from PH to PL and the steam temperature drops from TH to TL. From d to a, the heat medium 4 is isothermally heated with the pressure PL and vaporized.
With this configuration, the condensation temperature TH and the evaporation temperature TL can be maintained, the circulating water 2 can be cooled by the evaporator 38, and the hot water storage 3 can be heated by the condenser 34.

FIG. 3 is a schematic diagram showing the relationship between the heat transfer length and the temperature in the heat pump 30.
In this figure, the heat source inlet temperature is the temperature of the circulating water 2 heated by the photovoltaic panel 10 (for example, 50 to 60 ° C.). Further, the utilization temperature is the temperature of hot water heated by the heat pump 30 (for example, 70 to 80 ° C.).
In this case, the evaporation temperature TL is lower than the heat source inlet temperature, for example, 30 to 40 ° C. Further, the condensation temperature TH is higher than the utilization temperature, for example, 90 to 100 ° C.
The heat medium 4 of the heat pump 30 must satisfy the above-mentioned conditions, and is selected from well-known operating media (for example, R-11, R-12, etc.).

The heat pump 30 is not limited to the above-mentioned example, and may be another type of heat pump.

In FIG. 2, the heat collecting mat 20 has a flow path (pipe 22) through which the water supply 1 and the circulating water 2 flow.
Further, in this figure, the solar power generation hot water supply system 100 further includes a low temperature circulation line 50, a high temperature circulation line 60, a water supply line 70, and a hot water storage line 80.

The low temperature circulation line 50 has a low temperature circulation pump 52, and circulates the circulating water 2 between the heat collecting mat 20 and the evaporator 38 to cool the heat collecting mat 20. In this case, the circulating water 2 heated by the heat collecting mat 20 is supplied to the evaporator 38, and the circulating water 2 cooled by the evaporator 38 is resupplied to the heat collecting mat 20.

The high temperature circulation line 60 has a high temperature circulation pump 62, and circulates the hot water storage 3 between the hot water storage tank 40 and the condenser 34 to heat the hot water storage 3. In this case, the hot water storage 3 is supplied from the hot water storage tank 40 to the condenser 34, and the hot water storage 3 heated by the condenser 34 is returned to the hot water storage tank 40.

The water supply line 70 supplies water supply 1 to the heat collecting mat 20. The water supply 1 is preferably tap water having a low temperature (20 to 30 ° C.), for example.
With this configuration, even when the temperature of the circulating water after cooling is high (for example, 30 to 40 ° C), by using low temperature (20 to 30 ° C) tap water as the water supply 1, the photopower panel 10 is heated to the temperature of the circulating water 2. The power generation efficiency can be improved by cooling to the following.

The hot water storage line 80 supplies the water supply 1 heated by the heat collecting mat 20 to the hot water storage tank 40.
With this configuration, the water supply 1 heated by the heat collecting mat 20 (hereinafter, “heated water 1a”) is supplied to the hot water storage tank 40 as hot water of, for example, 50 to 60 ° C., so that the hot water storage 3 held in the hot water storage tank 40 The temperature of the water can be raised in advance.

In FIG. 2, the hot water storage line 80 has a hot water storage branch line 82 on the downstream side thereof. The hot water storage branch line 82 directly supplies the water supply 1 (heated water 1a) heated by the heat collecting mat 20 to the upstream side of the high temperature circulation line 60. It is preferable to provide 80a and 82a.
With this configuration, a part or all of the heated water 1a (for example, 50 to 60 ° C.) heated by the heat collecting mat 20 is directly supplied to the high temperature circulation line 60, and the hot water (heated water 1a) before being supplied to the hot water storage tank 40. ) Can be heated to a high temperature (for example, 70 to 80 ° C.) without an auxiliary heat source.

In FIG. 2, the photovoltaic power generation hot water supply system 100 further includes a control device 90. The control device 90 is, for example, a computer (PC), and controls the flow rate of the low temperature circulation line 50, the high temperature circulation line 60, or the water supply line 70.
The low temperature circulation line 50, the high temperature circulation line 60, the water supply line 70, and the hot water storage line 80 are provided with temperature sensors (not shown).

The control device 90 controls the flow rate of the low temperature circulation line 50 so that the temperature of the circulating water 2 flowing into the evaporator 38 is within a predetermined temperature range (for example, 50 to 60 ° C.).
With this configuration, the flow rate of the low temperature circulation line 50 can be controlled according to the increase or decrease of the energy of sunlight, and the temperature of the circulating water 2 after heating can be maintained within a predetermined temperature range. When the energy of sunlight is small (for example, at night) and the temperature of the circulating water 2 cannot be maintained at a predetermined temperature or higher (for example, 40 ° C. or higher), it is preferable to stop the circulation of the circulating water 2.

Further, the control device 90 controls the flow rate of the high temperature circulation line 60 so that the temperature of the hot water storage 3 flowing out of the condenser 34 is within a predetermined temperature range (for example, 70 to 80 ° C.).
With this configuration, the flow rate of the high temperature circulation line 60 can be controlled according to the increase or decrease of the energy of sunlight, and the temperature of the hot water storage 3 after heating can be maintained within a predetermined temperature range. If the energy of sunlight is small (for example, at night) and the temperature of the hot water storage 3 flowing out of the condenser 34 cannot be maintained above a predetermined temperature (for example, 60 ° C. or higher), the circulation of the hot water storage 3 is stopped. good.

When the circulation (operation) of the low temperature circulation line 50 and the high temperature circulation line 60 is stopped, the control device 90 preferably stops the operation of the heat pump 30. This stop can reduce the operating power of the heat pump 30 and increase the energy efficiency of the system.

The control device 90 also switches the supply destination of the water supply 1 (heated water 1a) to the hot water storage tank 40 or the high temperature circulation line 60 based on the temperature of the water supply 1 (heated water 1a) heated by the heat collecting mat 20.
For example, when the temperature of the heated water 1a heated by the heat collecting mat 20 is low, the hot water (heated water 1a) before being supplied to the hot water storage tank 40 is heated to a high temperature without an auxiliary heat source by switching to the high temperature circulation line 60. It can be heated to (for example, 70-80 ° C.).

FIG. 4 is a first embodiment view of the heat collecting mat 20. In this figure, (A) is a schematic view of the back surface of the photovoltaic power generation panel 10, and (B) is a sectional view taken along the line BB of (A).

In FIG. 4A, the heat collecting mat 20 has a pipe 22 (in this example, a common heat transfer pipe 22A) through which the water supply 1 and the circulating water 2 flow. In this example, the common heat transfer tube 22A is arranged close to the back surface of the photovoltaic power generation panel 10, and a single water supply 1 and circulating water 2 flow in the same surface from a single inlet to a single outlet. It is a heat transfer tube. The heat transfer tube is preferably made of metal or resin having high thermal conductivity.

In FIG. 4B, the heat collecting mat 20 further surrounds the metal leaf 24 that is continuously in close contact with the back surface of the photopower generation panel 10 and the outer peripheral surface of the pipe 22, and the back surface of the metal foil 24 and the pipe 22 to the outside. It has a heat insulating material 26 that suppresses heat dissipation to.
The entire outer peripheral surface of the pipe 22 is in close contact with the metal foil 24. The heat insulating material 26 is preferably a heat insulating material (for example, expanded polystyrene) having high heat insulating performance in the temperature range of the outside air temperature (for example, −20 ° C. to 50 ° C.).
With this configuration, the heat of the photovoltaic panel 10 heated by sunlight is transferred to the water supply 1 and the circulating water 2 via the metal leaf 24 and the pipe 22, so that the photovoltaic panel 10 is efficiently cooled. Can be done.

In FIG. 4A, the heat collecting mat 20 has a merging pipe 27 that merges the water supply 1 and the circulating water 2 and flows into the common heat transfer pipe 22A, and the mixed water flowing out from the common heat transfer pipe 22A is the water supply 1 and the circulating water. It has a branch pipe 28 that branches into two.
With this configuration, the combined water 1 and the circulating water 2 can be merged and flowed into the common heat transfer tube 22A by the merging pipe 27, and the mixed water flowing out from the common heat transfer tube 22A is heated by the branch pipe 28. It can be branched into (that is, heated water 1a) and circulating water 2.

FIG. 5 is a second embodiment view of the heat collecting mat 20. In this figure, (A) is a schematic view of the back surface of the photovoltaic power generation panel 10, and (B) is a sectional view taken along the line BB of (A).

In FIG. 5A, the combined pipe 27 is horizontally provided below the inclined heat collecting mat 20, and the water supply 1 and the circulating water 2 flow in from both ends thereof. Further, the branch pipe 28 is horizontally provided on the upper portion of the inclined heat collecting mat 20, and the water supply 1 and the circulating water 2 flow out from both ends thereof. The common heat transfer tube 22A is a plurality of straight tubes in this example, and communicates the confluence tube 27 and the branch tube 28, and is located at a distance from each other.
Other configurations are the same as those of the first embodiment.
Even with this configuration, the combined pipe 27 allows the water supply 1 and the circulating water 2 to merge and flow into the common heat transfer tube 22A, and the branch pipe 28 heats the mixed water flowing out of the common heat transfer tube 22A. It can be branched into 1 (that is, heated water 1a) and circulating water 2.

FIG. 6 is a third embodiment diagram of the heat collecting mat 20. In this figure, (A) is a schematic view of the back surface of the photovoltaic power generation panel 10, and (B) is a sectional view taken along the line BB of (A).

In FIGS. 6A and 6B, the pipe 22 has a water supply heat transfer tube 22B through which the water supply 1 flows independently and a circulating water heat transfer tube 22C through which the circulating water 2 flows independently.
In this example, the circulating water heat transfer tube 22C is close to the back surface of the photovoltaic power generation panel 10, and the circulating water 2 flows independently from the plurality of inlets to the plurality of outlets.
Further, the water supply heat transfer tube 22B is close to the back surface of the circulating water transfer tube 22C, and the water supply 1 flows independently from the plurality of inlets to the plurality of outlets.
The water supply heat transfer tube 22B and the circulating water transfer tube 22C may be provided independently in the same plane.
With this configuration, it is possible to prevent the water supply 1 and the circulating water 2 from being mixed and to control each of them independently.

According to the above-described embodiment of the present invention, the heat collecting mat 20 has a flow path through which the water supply 1 and the circulating water 2 flow. As a result, even when the circulating water temperature for cooling is high, for example, by using low temperature (20 to 30 ° C.) tap water as the water supply 1, the photovoltaic panel 10 is cooled to the circulating water temperature or lower to improve the power generation efficiency. be able to.

Further, since the water supply 1 heated by the heat collecting mat 20 is supplied to the hot water storage tank 40 or the high temperature circulation line 60 as hot water (for example, 50 to 60 ° C.) by the hot water storage line 80, the hot water storage 3 held in the hot water storage tank 40 The temperature can be raised in advance.

Further, the heat pump 30 uses the circulating water 2 (for example, 30 to 40 ° C.) heated by the heat collecting mat 20 as a heat source, and the hot water storage 3 (for example, 50 to 60 ° C.) circulates between the hot water storage tank 40 and the condenser 34. To heat. As a result, the hot water storage 3 held in the hot water storage tank 40 can be heated to a high temperature (for example, 70 to 80 ° C.) without an auxiliary heat source.

Therefore, since the hot water storage 3 having a high temperature (for example, 70 to 80 ° C.) can be stored in the hot water storage tank 40, the hot water storage tank 40 for holding the required amount in the house can be miniaturized.

It should be noted that the present invention is not limited to the above-described embodiment, and of course, various modifications can be made without departing from the gist of the present invention.

1 Water supply, 2 Circulating water, 3 Hot water storage, 4 Heat medium, 10 Photovoltaic panel,
20 heat collecting mat, 22 piping, 22A common heat transfer tube, 22B water supply heat transfer tube,
22C circulating water heat transfer tube, 24 metal leaf, 26 heat insulating material, 27 combined tube,
28 branch tube, 30 heat pump, 32 compressor, 34 condenser,
36 Inflator, 38 Evaporator, 40 Hot Water Storage Tank, 50 Low Temperature Circulation Line,
52 low temperature circulation pump, 60 high temperature circulation line, 62 high temperature circulation pump,
70 water supply line, 80 hot water storage line, 82 hot water storage branch line,
80a, 82a flow control valve, 90 control device,
100 solar power generation hot water supply system

Claims (6)

Photovoltaic panels that generate electricity from sunlight and
A heat collecting mat attached to the back surface of the photovoltaic power generation panel, having a flow path through which water supply and circulating water flow, and cooling the photovoltaic power generation panel,
A heat pump that has a compressor, a condenser, an expander, and an evaporator, and a heat medium circulates inside.
A hot water storage tank that holds hot water inside, and
A low-temperature circulation line that circulates the circulating water between the heat collecting mat and the evaporator and cools the heat collecting mat.
A high-temperature circulation line that circulates the hot water between the hot water storage tank and the condenser and heats the hot water storage.
A water supply line that supplies the water supply to the heat collecting mat,
A hot water storage line that supplies the water supplied heated by the heat collecting mat to the hot water storage tank or the high temperature circulation line .
A photovoltaic hot water supply system including a control device for controlling the flow rate of the low temperature circulation line so that the temperature of the circulating water flowing into the evaporator is within a predetermined temperature range . Photovoltaic panels that generate electricity from sunlight and
A heat collecting mat attached to the back surface of the photovoltaic power generation panel, having a flow path through which water supply and circulating water flow, and cooling the photovoltaic power generation panel,
A heat pump that has a compressor, a condenser, an expander, and an evaporator, and a heat medium circulates inside.
A hot water storage tank that holds hot water inside, and
A low-temperature circulation line that circulates the circulating water between the heat collecting mat and the evaporator and cools the heat collecting mat.
A high-temperature circulation line that circulates the hot water between the hot water storage tank and the condenser and heats the hot water storage.
A water supply line that supplies the water supply to the heat collecting mat,
A hot water storage line that supplies the water supplied heated by the heat collecting mat to the hot water storage tank or the high temperature circulation line .
A photovoltaic power generation hot water supply system including a control device for controlling the flow rate of the high temperature circulation line so that the temperature of the hot water flowing out of the condenser is within a predetermined temperature range . Photovoltaic panels that generate electricity from sunlight and
A heat collecting mat attached to the back surface of the photovoltaic power generation panel, having a flow path through which water supply and circulating water flow, and cooling the photovoltaic power generation panel,
A heat pump that has a compressor, a condenser, an expander, and an evaporator, and a heat medium circulates inside.
A hot water storage tank that holds hot water inside, and
A low-temperature circulation line that circulates the circulating water between the heat collecting mat and the evaporator and cools the heat collecting mat.
A high-temperature circulation line that circulates the hot water between the hot water storage tank and the condenser and heats the hot water storage.
A water supply line that supplies the water supply to the heat collecting mat,
A hot water storage line that supplies the water supplied heated by the heat collecting mat to the hot water storage tank or the high temperature circulation line .
A control device for controlling the flow rate of the low temperature circulation line, the high temperature circulation line, or the water supply line is provided.
The control device is a solar power generation hot water supply system that switches the supply destination of the water supply to the hot water storage tank or the high temperature circulation line based on the temperature of the water supply heated by the heat collecting mat . Photovoltaic panels that generate electricity from sunlight and
A heat collecting mat attached to the back surface of the photovoltaic power generation panel, having a flow path through which water supply and circulating water flow, and cooling the photovoltaic power generation panel,
A heat pump that has a compressor, a condenser, an expander, and an evaporator, and a heat medium circulates inside.
A hot water storage tank that holds hot water inside, and
A low-temperature circulation line that circulates the circulating water between the heat collecting mat and the evaporator and cools the heat collecting mat.
A high-temperature circulation line that circulates the hot water between the hot water storage tank and the condenser and heats the hot water storage.
A water supply line that supplies the water supply to the heat collecting mat,
A hot water storage line for supplying the water supply heated by the heat collecting mat to the hot water storage tank or the high temperature circulation line is provided .
The heat collecting mat is arranged close to the back surface of the photovoltaic power generation panel, and has a pipe through which the water supply or the circulating water flows.
A metal foil that continuously adheres to the back surface and the outer peripheral surface of the pipe,
A solar power generation hot water supply system having a heat insulating material that surrounds the metal foil and the back surface of the pipe and suppresses heat dissipation to the outside . The pipe is a common heat transfer pipe through which the water supply and the circulating water flow.
The heat collecting mat includes a merging pipe that merges the water supply and the circulating water and flows into the common heat transfer pipe, and a branch pipe that branches the mixed water flowing out of the common heat transfer pipe into the water supply and the circulating water. The solar power generation hot water supply system according to claim 4 . The solar power generation hot water supply system according to claim 4 , wherein the pipe has a water supply heat transfer pipe through which the water supply flows independently and a circulating water heat transfer pipe through which the circulating water flows independently.

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