Air conditioning / hot water supply system

Abstract

Provided is an air conditioning / hot water supply system capable of efficiently performing heat storage with respect to a hot water storage tank by using electric power from photovoltaic power generation, suppressing reverse power flow of the electric power to a system of a power company, and performing the heat storage with respect to the hot water storage tank at the same time as an air conditioning operation. To this end, the air conditioning / hot water supply system comprises: a heat source machine having a refrigeration cycle; an air conditioning device for performing air conditioning using the heat source machine as a heat source; a hot water storage unit having a hot water storage tank for storing heated hot water; a control device for causing a first hot water supply operation using the heat source machine as the heat source to be performed until the temperature of the hot water in the hot water storage tank reaches a first set temperature; and an electric heater for heating the hot water in the hot water storage tank. In a case where the air conditioning device is performing the air conditioning operation using the heat source machine as the heat source and the generated power of a photovoltaic power generation device is equal to or greater than reference power, the control device causes the electric heater to perform a second hot water supply operation for heating the hot water in the hot water storage tank until the temperature of the hot water in the hot water storage tank reaches a second set temperature obtained by adding an additional value to the first set temperature.

Description

Air conditioning and hot water supply system

[0001] The present disclosure relates to an air conditioning and hot water supply system.

[0002] An air conditioning and hot water supply system is known that includes a solar cell unit, an air conditioning unit, two or more hot water storage tanks that absorb heat from a heat storage tank on the high-temperature water side of the air conditioning unit on an alternate-day cycle, a control device, and an inverter that converts the power obtained from the solar cells into AC.The control device is equipped with a reverse flow means that compares in advance the power value required to operate the air conditioning unit the next day with the power value generated by the solar cell unit on that day, and if surplus power is generated in the solar cell unit, causes the surplus power to flow reversely to the electric power company via the inverter (see, for example, Patent Document 1).

[0003] Japanese Patent Publication No. 06-241685

[0004] However, in an air conditioning and hot water supply system such as that disclosed in Patent Document 1, power consumption fluctuates greatly, and if the surplus power fluctuates greatly, there is a possibility that an unexpected power flow will occur in the reverse direction to the power company's grid. If an unexpected power flow occurs in the reverse direction to the power company's grid, there is a risk of a power outage or the like occurring.

[0005] The present disclosure has been made to solve these problems. Its purpose is to provide an air conditioning and hot water supply system that efficiently stores heat in a hot water storage tank using electricity generated by solar power, suppresses reverse power flow to the power company's grid, and is capable of simultaneously operating the air conditioning system and storing heat in the hot water storage tank.

[0006] The air conditioning and hot water supply system of the present disclosure comprises a heat source machine having a refrigeration cycle, an air conditioning device that performs air conditioning using the heat source machine as a heat source, a hot water storage unit having a hot water storage tank that stores heated hot water, a control device that performs a first hot water supply operation using the heat source machine as a heat source until the temperature of the hot water in the hot water storage tank reaches a first set temperature, and an electric heater that heats the hot water in the hot water storage tank, and when the air conditioning device is performing air conditioning operation using the heat source machine as a heat source and the power generation power of a solar power generation device is equal to or greater than a reference power, the control device performs a second hot water supply operation in which the electric heater heats the hot water in the hot water storage tank until the temperature of the hot water in the hot water storage tank reaches a second set temperature obtained by adding an additional value to the first set temperature.

[0007] The air conditioning and hot water supply system of the present disclosure has the advantage that it can efficiently store heat in a hot water storage tank using electricity generated by solar power, suppressing the reverse flow of electricity to the power company's grid, and enabling air conditioning operation and heat storage in the hot water storage tank to be performed simultaneously.

[0008] 1 is a diagram showing a schematic configuration of an electrical system of an air conditioning and hot water supply system according to embodiment 1. FIG. 2 is a system circuit diagram showing the overall configuration of an air conditioning and hot water supply system according to embodiment 1. FIG. 3 is a block diagram showing the configuration of a heat pump control device of an air conditioning and hot water supply system according to embodiment 1. FIG. 4 is a block diagram showing the configuration of a hydro control device of an air conditioning and hot water supply system according to embodiment 1. FIG. 5 is a system circuit diagram showing the overall configuration of an air conditioning and hot water supply system according to embodiment 1. FIG. 6 is a system circuit diagram showing the overall configuration of an air conditioning and hot water supply system according to embodiment 1. FIG. 7 is a flow diagram showing an example of operation of an air conditioning and hot water supply system according to embodiment 1. FIG. 8 is a flow diagram showing an example of operation of an air conditioning and hot water supply system according to embodiment 1. FIG. 9 is a diagram explaining an example of a change in the operating state of the air conditioning and hot water supply system according to embodiment 1. FIG. 10 is a system circuit diagram showing the overall configuration of another example of the air conditioning and hot water supply system according to embodiment 1. FIG. 11 is a diagram showing an example of a configuration that realizes the functions of the heat pump control device and the hydro control device of the air conditioning and hot water supply system according to embodiment 1.

[0009] An embodiment of an air conditioning and hot water supply system according to the present disclosure will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations are appropriately simplified or omitted. For convenience, the following description may express the positional relationship of each structure based on the illustrated state. Note that the present disclosure is not limited to the following embodiments, and any combination of the embodiments, any modification of any component of each embodiment, or any omission of any component of each embodiment are possible within the scope of the present disclosure.

[0010] Embodiment 1. Embodiment 1 of the present disclosure will be described with reference to Figures 1 to 10. Figure 1 is a diagram showing the schematic configuration of the electrical system of an air conditioning and hot water supply system. Figures 2, 5, and 6 are each a system circuit diagram showing the overall configuration of an air conditioning and hot water supply system. Figure 3 is a block diagram showing the configuration of a heat pump control device of an air conditioning and hot water supply system. Figure 4 is a block diagram showing the configuration of a hydro control device of an air conditioning and hot water supply system. Figures 7 and 8 are flow diagrams showing an example of the operation of an air conditioning and hot water supply system. Figure 9 is a diagram explaining an example of a change in the operating state of an air conditioning and hot water supply system. Figure 10 is a system circuit diagram showing the overall configuration of another example of an air conditioning and hot water supply system. Figure 11 is a diagram showing an example of a configuration that realizes the functions of the heat pump control device and hydro control device of an air conditioning and hot water supply system.

[0011] As shown in Fig. 1, the power system of the air conditioning and hot water supply system according to this embodiment is equipped with a solar power generation device 400. The solar power generation device 400 includes a plurality of solar cell panels (not shown). The solar cell panels are capable of receiving light and generating electricity. The solar power generation device 400 is connected to a power conditioner 420 via a connecting member 410. The power conditioner 420 has functions such as converting DC power generated by the solar power generation device 400 into AC power.

[0012] The power conditioner 420 is connected to a distribution board 430. The AC power converted by the power conditioner 420 is transmitted to the distribution board 430. The distribution board 430 supports two-system interconnection between a commercial power source and the solar power generation device 400. The distribution board 430 has an automatic power supply control function. That is, when the power generated by the solar power generation device 400 is less than the power consumed, the distribution board 430 covers the shortfall with commercial power. Conversely, when the power generated by the solar power generation device 400 is greater than the power consumed, the distribution board 430 can reverse flow the surplus power and sell it to the power company.

[0013] The distribution board 430 is connected to the heat pump system 100. The distribution board 430 supplies one or both of the power generated by the solar power generation device 400 and commercial power to the heat pump system 100. The heat pump system 100 is driven by the power supplied from the distribution board 430.

[0014] Fig. 4 is a system circuit diagram of a heat pump system 100 according to this embodiment. As shown in Fig. 4, the heat pump system 100 according to this embodiment includes a heat pump unit 301, a hot water storage tank unit 302, and an air conditioning unit 305. The heat pump unit 301 is a unit equipped with a refrigerant circuit 51 and a part of a heat medium circulation circuit 52 of a vapor compression refrigeration cycle (heat pump cycle). The hot water storage tank unit 302 is a unit equipped with a part of the heat medium circulation circuit 52 and a hot water storage circuit 53.

[0015] The air conditioning unit 305 is a unit that is configured as part of the heat medium circulation circuit 52 and heats the room. In the illustrated configuration example, two air conditioning units 305 are provided: a first air conditioning unit 305a and a second air conditioning unit 305b. The number of air conditioning units 305 is not limited to two, and may be one, or three or more. In the present disclosure, the first air conditioning unit 305a and the second air conditioning unit 305b are collectively referred to as air conditioning unit 305 when they are not distinguished from each other.

[0016] The heat pump unit 301 and the hot water storage tank unit 302 are connected via a first heat medium pipe 303 and a second heat medium pipe 304. The hot water storage tank unit 302 and the air conditioning unit 305 are connected via a third heat medium pipe 306 and a fourth heat medium pipe 307. The hot water storage tank unit 302 is also connected to a hot water supply pipe 308 and a water supply pipe 309. The hot water supply pipe 308 is a pipe connected to a hot water terminal (not shown) (for example, a faucet in a kitchen or bathroom). The water supply pipe 309 is a pipe for supplying water from a water source (not shown), such as a tap. The heat pump system 100 according to the present disclosure corresponds to a hot water supply and air conditioning system equipped with a hot water supply function and an air conditioning function.

[0017] The refrigerant used in the refrigerant circuit 51 of the heat pump unit 301 is not particularly limited, and for example, natural refrigerants such as R410A, R32, HFO-1234yf, hydrocarbons, or carbon dioxide can be used. In addition, the heat medium used in the heat medium circulation circuit 52 is not particularly limited, and for example, liquids such as water, ethylene glycol, propylene glycol, or mixtures thereof can be used. In addition, ethylene glycol, propylene glycol, etc. can be used in any concentration.

[0018] The heat pump system 100 is installed in, for example, an ordinary house or an office building, etc. The heat pump system 100 can process a hot water supply command (hot water supply ON / OFF), a cooling command (cooling ON / OFF), or a heating command (heating ON / OFF) selected by the hot water storage tank unit 302.

[0019] The heat pump unit 301 is equipped with a refrigerant circuit 51. The refrigerant circuit 51 is a circuit in which a compressor 1, a liquid heat exchanger 2, an expansion valve 3, a heat source heat exchanger 4, and a four-way valve 21 are connected in a ring shape by refrigerant piping, and through which a refrigerant circulates. The compressor 1 draws in and compresses the refrigerant to a high temperature and high pressure state. The compressor 1 is preferably a type whose rotational speed is controlled, for example, by inverter control. The liquid heat exchanger 2 exchanges heat between a heat medium and the refrigerant, thereby heating the heat medium and cooling the refrigerant, or cooling the heat medium and heating the refrigerant. The liquid heat exchanger 2 is, for example, a plate-type heat exchanger. The expansion valve 3 decompresses the refrigerant to a low temperature and low pressure state. The opening degree of the expansion valve 3 is variable. The heat source heat exchanger 4 exchanges heat between the refrigerant and outside air, thereby absorbing heat from the outside air to heat the refrigerant, or releasing heat to the outside air to cool the refrigerant. The heat source heat exchanger 4 is, for example, a cross-fin type fin-and-tube air heat exchanger composed of heat transfer tubes and multiple fins. A blower 5 is installed in the heat source heat exchanger 4. The blower 5 draws in outside air, exchanges heat in the heat source heat exchanger 4, and then discharges the air to the outside. The blower 5 includes a fan such as a propeller fan and a motor, for example, a DC fan motor, that drives the fan. The blower 5 is configured to vary the flow rate of the supplied air. The four-way valve 21 switches the circulation direction of the refrigerant in the refrigerant circuit 51. The heat pump unit 301 corresponds to a heat source machine having a refrigeration cycle.

[0020] The heat pump unit 301 further includes a pressure sensor 201, a first temperature sensor 202, a second temperature sensor 203, a third temperature sensor 204, a fourth temperature sensor 205, a fifth temperature sensor 206, and a sixth temperature sensor 207. The pressure sensor 201 detects the pressure of the refrigerant discharged from the compressor 1. The first temperature sensor 202 detects the temperature of the refrigerant discharged from the compressor 1. The second temperature sensor 203 detects the temperature of the refrigerant flowing out from the liquid heat exchanger 2. The third temperature sensor 204 detects the temperature of the refrigerant flowing into the heat source heat exchanger 4. The fourth temperature sensor 205 detects the temperature of the air flowing into the heat source heat exchanger 4, i.e., the outside air temperature. The fifth temperature sensor 206 detects the temperature of the heat medium flowing into the liquid heat exchanger 2. The sixth temperature sensor 207 detects the temperature of the heat medium flowing out from the liquid heat exchanger 2.

[0021] The hot water storage tank unit 302 is equipped with a heat medium pump 6, a three-way valve 7, a heating heat exchanger 8, a water pump 9, a hot water storage tank 10, and a mixing valve 11. The heat medium pump 6 circulates the heat medium through a heat medium circulation circuit 52. The heat medium pump 6 may be a variable-speed pump (e.g., inverter-controlled) or a constant-speed pump. The three-way valve 7 functions as a flow path switching device for switching the flow direction of the heat medium. During hot water supply operation, in which hot water is supplied to the hot water storage tank 10 and heat is stored therein, the three-way valve 7 is switched so that the heat medium flows to the heating heat exchanger 8. During air-conditioning operation, the three-way valve 7 is switched so that the heat medium flows to the air-conditioning unit 305. The heating heat exchanger 8 heats the water and cools the heat medium by exchanging heat between the heat medium and water. The heating heat exchanger 8 is, for example, a plate-type heat exchanger. In the configuration example described here, the heat medium and water flow in opposite directions within the heating heat exchanger 8. The water pump 9 circulates water through the hot water storage circuit 53. The water pump 9 may be a variable-speed pump (e.g., inverter-controlled) or a constant-speed pump. The hot water storage tank 10 stores heated hot water and unheated water. The hot water storage tank 10 is a full-capacity tank. One end of the hot water storage circuit 53 is connected to a first connection point 14 at the bottom of the hot water storage tank 10. The other end of the hot water storage circuit 53 is connected to a second connection point 17 at the bottom of the hot water storage tank 10, which is located higher than the first connection point 14. When the water pump 9 is driven, water in the hot water storage tank 10 flows out from the first connection point 14, is sent to the heating heat exchanger 8, is heated, returns to the hot water storage tank 10, and flows into the hot water storage tank 10 through the second connection point 17.

[0022] The hot water outlet pipe 15 connects the top of the hot water storage tank 10 to the mixing valve 11. The water supply pipe 309 is connected to the bottom of the hot water storage tank 10 and the mixing valve 11. A hot water supply pipe 308 is also connected to the mixing valve 11. In response to a user's hot water request, hot water flows out from the top of the hot water storage tank 10 to the hot water outlet pipe 15 and is supplied to the mixing valve 11. At this time, low-temperature water in an amount equal to the hot water flowing out to the hot water outlet pipe 15 flows from the water supply pipe 309 into the bottom of the hot water storage tank 10. The mixing valve 11 mixes the hot water from the hot water outlet pipe 15 with the low-temperature water from the water supply pipe 309 and supplies the water to the hot water supply pipe 308. The mixing valve 11 is capable of controlling the mixing ratio of hot water and low-temperature water, and generates hot water at a set temperature.

[0023] The hot water storage tank unit 302 further includes a seventh temperature sensor 208, an eighth temperature sensor 209, a ninth temperature sensor 210, a tenth temperature sensor 211, an eleventh temperature sensor 212, and a twelfth temperature sensor 216. The seventh temperature sensor 208 is a sensor that detects the temperature of the heat medium flowing into the heating heat exchanger 8. The eighth temperature sensor 209 is a sensor that detects the temperature of the heat medium flowing out from the heating heat exchanger 8. The ninth temperature sensor 210 is a sensor that detects the temperature of the water flowing into the heating heat exchanger 8. The tenth temperature sensor 211 is a sensor that detects the temperature of the water flowing out from the heating heat exchanger 8. The eleventh temperature sensor 212 is a sensor that detects the water temperature in the hot water storage tank 10. The twelfth temperature sensor 216 is a sensor that detects the water temperature in the hot water supply pipe 308.

[0024] The air conditioning unit 305 includes an air conditioning heat exchanger 12. In the illustrated configuration example, the first air conditioning unit 305a includes a first air conditioning heat exchanger 12a. The second air conditioning unit 305b includes a second air conditioning heat exchanger 12b. In the present disclosure, the first air conditioning heat exchanger 12a and the second air conditioning heat exchanger 12b are collectively referred to as the air conditioning heat exchanger 12 without distinction. By flowing a heat medium through the air conditioning heat exchanger 12, indoor air can be cooled or heated. Although not illustrated, the air conditioning unit 305 may also include an air conditioning fan that takes indoor air around the air conditioning heat exchanger 12 and sends the cooled or heated air into the room.

[0025] The heat pump unit 301 is provided with a heat pump control device 101, which is implemented, for example, by a microcomputer. The heat pump control device 101 corresponds to a control circuit. The hot water storage tank unit 302 is provided with a hydro control device 121, which is implemented, for example, by a microcomputer. The hydro control device 121 corresponds to a control circuit. FIG. 2 is a block diagram showing the configuration of the heat pump control device 101. As shown in the figure, the heat pump control device 101 includes a heat pump measurement means 102, a heat pump communication means 103, a heat pump calculation means 104, and a heat pump control means 105.

[0026] The heat pump measurement means 102 acquires pressure and temperature information as measurement information based on the outputs of the pressure sensor 201, the first temperature sensor 202, the second temperature sensor 203, the third temperature sensor 204, the fourth temperature sensor 205, the fifth temperature sensor 206, and the sixth temperature sensor 207. The heat pump communication means 103 transmits the operating status (temperature, pressure, etc.) of the heat pump unit 301, abnormality signals, etc. to the hydro control device 121. The heat pump communication means 103 also receives the operating status (temperature, equipment operation, etc.) and abnormality signals of the hot water storage tank unit 302 from the hydro control device 121. The heat pump calculation means 104 calculates the condensing temperature, the degree of subcooling, etc. based on the measurement information acquired by the heat pump measurement means 102. The heat pump control means 105 controls the operating state of the heat pump unit 301 (such as the operating method of the compressor 1 and the opening degree of the expansion valve 3) based on the measurement information acquired by the heat pump measurement means 102 and the calculation results of the heat pump calculation means 104. The heat pump communication means 103 is configured to communicate with the hydro communication means 125 (described later) via, for example, a telephone line, a LAN line, or wireless communication.

[0027] FIG. 3 is a block diagram showing the configuration of the hydro control device 121. As shown in the figure, the hydro control device 121 includes a hydro measurement means 122, a memory means 123, an input means 124, a hydro communication means 125, a hydro calculation means 126, and a hydro control means 127. The hydro measurement means 122 acquires temperature information as measurement information based on the outputs of the seventh temperature sensor 208, the eighth temperature sensor 209, the ninth temperature sensor 210, the tenth temperature sensor 211, the eleventh temperature sensor 212, and the twelfth temperature sensor 216. The memory means 123 stores the type of heat medium flowing through the heat medium circulation circuit 52, etc. The input means 124 recognizes inputs such as an operation mode ON / OFF command from the user and input information from the installation company. The hydro communication means 125 transmits the operating status (temperature, equipment operation, etc.) of the hot water storage tank unit 302, abnormality signals, etc. to the heat pump control device 101. Furthermore, the hydro communication means 125 receives the operating state (temperature, pressure, etc.) of the heat pump unit 301, abnormality signals, etc. from the heat pump control device 101. The hydro calculation means 126 calculates the temperature difference of the water entering and leaving the heating heat exchanger 8 and the temperature difference of the heat medium entering and leaving the heating heat exchanger 8, etc., based on the measurement information acquired by the hydro measurement means 122. The hydro control means 127 controls the operating state of the hot water storage tank unit 302 (the operating states of the heat medium pump 6 and the water pump 9, switching of the three-way valve 7, etc.) based on the measurement information acquired by the hydro measurement means 122, the calculation results of the hydro calculation means 126, etc.

[0028] The hydro control device 121 is further connected to a power meter 141, a remote control device 251, and a flow sensor 131. The power meter 141 measures the power consumption of the heat pump unit 301, which is a refrigeration cycle device. The flow sensor 131 detects the volumetric flow rate of the heat medium flowing through the heat medium circulation circuit 52.

[0029] The remote control device 251 is an example of a user interface. By operating the remote control device 251, a person such as a user can remotely control the heat pump system 100 and perform various settings. The communication between the hydro control device 121 and the remote control device 251 may be wired or wireless. The remote control device 251 may be installed in the bathroom. The remote control device 251 may be installed in the kitchen. The heat pump system 100 may include multiple remote control devices 251 installed in different locations. The remote control device 251 includes a display unit, an operation unit, and an audio output unit. The display unit may be, for example, a liquid crystal display or an organic electroluminescence (EL) display. The display unit can display, for example, information regarding the status of the heat pump system 100, information regarding the settings of the heat pump system 100, etc. The display unit functions as a notification means for notifying a person such as a user of information. The operation unit may include buttons, dials, keys, etc. for user operation. The display unit may be a touch screen that also functions as the operation unit. The audio output unit functions as a notification unit that notifies a person such as a user by audio of information. Instead of or in addition to the remote control device 251, a configuration may be adopted in which a smartphone or other portable device can be used as a user interface.

[0030] In the configuration example described here, the heat pump control device 101 is installed in the heat pump unit 301, and the hydro control device 121 is installed in the hot water storage tank unit 302. However, the configuration is not limited to this, and the heat pump control device 101 may be installed in the hot water storage tank unit 302, or the hydro control device 121 may be installed in the heat pump unit 301. The heat pump control device 101 and the hydro control device 121 may also be integrated. Alternatively, a control device (not shown) may be provided in a location other than the heat pump unit 301 and the hot water storage tank unit 302, and the control device may take over some or all of the functions of the heat pump control device 101 and the hydro control device 121.

[0031] The heat pump system 100 controls each device installed in the heat pump unit 301, the hot water storage tank unit 302, and the air conditioning unit 305 in accordance with the air conditioning load required of the air conditioning unit 305 and the hot water supply demand required of the hot water storage tank unit 302, and executes a chilled water cooling operation mode, a hot water heating operation mode, or a hot water supply operation mode. ON / OFF information for the chilled water cooling operation mode, the hot water heating operation mode, or the hot water supply operation mode is input to the input means 124 of the hydro control device 121 by the user or automatically based on the time, etc. The input information is transmitted to the heat pump control device 101 by the communication means 125. The operating operations in each operation mode are described below.

[0032] First, the chilled water cooling operation mode will be described. Arrows in FIG. 4 indicate the flow directions of the refrigerant and heat medium in the chilled water cooling operation mode. In the chilled water cooling operation mode, the four-way valve 21 is switched to connect the outlet of the compressor 1 to the inlet of the heat-source heat exchanger 4. The three-way valve 7 is also switched to connect the outlet of the liquid heat exchanger 2 to the air conditioning unit 305. In this state, the heat pump unit 301 and the hot water storage tank unit 302 are operated. Then, in the refrigerant circuit 51, high-temperature, high-pressure gas refrigerant discharged from the compressor 1 flows into the heat-source heat exchanger 4 and is cooled by outside air to become high-pressure liquid refrigerant. The refrigerant then flows out of the heat-source heat exchanger 4 and is decompressed by the expansion valve 3 to become a low-pressure two-phase refrigerant. The refrigerant then flows into the liquid heat exchanger 2, absorbs heat from the heat medium, and becomes a low-pressure gas refrigerant. The refrigerant is then drawn back into the compressor 1.

[0033] The operating states of the compressor 1, expansion valve 3, and blower 5 are controlled by the heat pump control means 105 of the heat pump control device 101 in accordance with the temperature or pressure measured by the heat pump measurement means 102. Specifically, for example, the rotation speed of the blower 5 is determined in accordance with the outside air temperature. The frequency of the compressor 1 is controlled so that the outlet hot water temperature, i.e., the temperature detected by the sixth temperature sensor 207, becomes the set water temperature. The opening of the expansion valve 3 is controlled so that the degree of subcooling in the heat source heat exchanger 4, which functions as a condenser, becomes 5°C.

[0034] Meanwhile, in the heat medium circulation circuit 52, the heat medium sent by the heat medium pump 6 flows out of the hot water storage tank unit 302 and flows into the heat pump unit 301 via the heat medium piping 304. After flowing into the heat pump unit 301, the heat medium is cooled by the refrigerant in the liquid heat exchanger 2 and becomes a low-temperature state. This low-temperature heat medium flows out of the heat pump unit 301 and flows back into the hot water storage tank unit 302 via the heat medium piping 303. The heat medium then flows out of the hot water storage tank unit 302 via the three-way valve 7 and flows into the air conditioning unit 305 via the heat medium piping 306. The heat medium exchanges heat with the indoor air in the air conditioning heat exchanger 12 to cool the room, and the heat medium becomes hot. The hot heat medium flows out of the air conditioning unit 305 and flows into the hot water storage tank unit 302 via the heat medium piping 307, and then flows into the heat medium pump 6 again.

[0035] The operating state of the heat medium pump 6 is controlled by the hydro control means 127 of the hydro control device 121. Specifically, for example, the rotation speed of the heat medium pump 6 is determined to a set rotation speed. The set rotation speed of the heat medium pump 6 is set, for example, by operating the remote control device 251. Note that in the chilled water cooling operation mode, the water in the hot water storage tank 10 is not heated, so the water pump 9 is stopped and water does not flow in the hot water storage circuit 53.

[0036] Next, the hot water heating operation mode will be described with reference to FIG. 5 . The arrows in FIG. 5 indicate the flow directions of the refrigerant and heat transfer medium in the hot water heating operation mode. In the hot water heating operation mode, the four-way valve 21 is switched to connect the outlet of the compressor 1 to the inlet of the liquid heat exchanger 2. The three-way valve 7 is also switched to connect the outlet of the liquid heat exchanger 2 to the air conditioning unit 305. In this state, the heat pump unit 301 and the hot water storage tank unit 302 are operated. Then, in the refrigerant circuit 51, high-temperature, high-pressure gas refrigerant discharged from the compressor 1 flows into the liquid heat exchanger 2 and is cooled by the heat transfer medium to become high-pressure liquid refrigerant. The refrigerant then flows out of the liquid heat exchanger 2 and is decompressed by the expansion valve 3 to become a low-pressure two-phase refrigerant. The refrigerant then flows into the heat source heat exchanger 4, where it absorbs heat from the outside air and becomes a low-pressure gas refrigerant. The refrigerant is then drawn back into the compressor 1.

[0037] The operating states of the compressor 1, expansion valve 3, and blower 5 are controlled by the heat pump control means 105 of the heat pump control device 101 in accordance with the temperature or pressure measured by the heat pump measurement means 102. Specifically, for example, the rotation speed of the blower 5 is determined in accordance with the outside air temperature. The frequency of the compressor 1 is controlled so that the outlet hot water temperature, i.e., the temperature detected by the sixth temperature sensor 207, becomes the set water temperature. The opening of the expansion valve 3 is controlled so that the degree of subcooling in the liquid heat exchanger 2, which functions as a condenser, becomes 5°C.

[0038] Meanwhile, in the heat medium circulation circuit 52, the heat medium sent by the heat medium pump 6 flows out of the hot water storage tank unit 302 and flows into the heat pump unit 301 via the heat medium piping 304. After flowing into the heat pump unit 301, the heat medium is heated by the refrigerant in the liquid heat exchanger 2 and reaches a high temperature. This high-temperature heat medium flows out of the heat pump unit 301 and flows back into the hot water storage tank unit 302 via the heat medium piping 303. The heat medium then flows out of the hot water storage tank unit 302 via the three-way valve 7 and flows into the air conditioning unit 305 via the heat medium piping 306. The heat medium exchanges heat with the indoor air in the air conditioning heat exchanger 12, heating the room, and the heat medium becomes cold. The cooled heat medium flows out of the air conditioning unit 305, flows into the hot water storage tank unit 302 via the heat medium piping 307, and flows back into the heat medium pump 6.

[0039] The operating state of the heat medium pump 6 is controlled by the hydro control means 127 of the hydro control device 121. Specifically, for example, the rotation speed of the heat medium pump 6 is determined to a set rotation speed. The set rotation speed of the heat medium pump 6 is set, for example, by operating the remote control device 251. Note that in the hot water heating operation mode, the water in the hot water storage tank 10 is not heated, so the water pump 9 is stopped and water does not flow in the hot water storage circuit 53.

[0040] Next, the hot water supply operation mode will be described with reference to FIG. 6 . The arrows in FIG. 6 indicate the flow directions of the refrigerant, heat transfer medium, and water in the hot water supply operation mode. In the hot water supply operation mode, the four-way valve 21 is switched to connect the outlet of the compressor 1 to the inlet of the liquid heat exchanger 2. The three-way valve 7 is also switched to connect the outlet of the liquid heat exchanger 2 to the inlet of the heating heat exchanger 8. In this state, the heat pump unit 301 and the hot water storage tank unit 302 are operated. Then, in the refrigerant circuit 51, high-temperature, high-pressure gas refrigerant discharged from the compressor 1 flows into the liquid heat exchanger 2 and is cooled by the heat transfer medium to become high-pressure liquid refrigerant. The refrigerant then flows out of the liquid heat exchanger 2 and is decompressed by the expansion valve 3 to become a low-pressure two-phase refrigerant. The refrigerant then flows into the heat source heat exchanger 4, where it absorbs heat from the outside air and becomes a low-pressure gas refrigerant. The refrigerant is then drawn back into the compressor 1.

[0041] The operating states of the compressor 1, expansion valve 3, and blower 5 are controlled by the heat pump control means 105 of the heat pump control device 101 in accordance with the temperature or pressure measured by the heat pump measurement means 102. Specifically, for example, the rotation speed of the blower 5 is determined in accordance with the outside air temperature. The frequency of the compressor 1 is controlled to be fixed at a preset hot water supply operation frequency. The opening of the expansion valve 3 is controlled so that the degree of subcooling in the liquid heat exchanger 2, which functions as a condenser, is 5°C.

[0042] Meanwhile, in the heat medium circulation circuit 52, the heat medium sent by the heat medium pump 6 flows out of the hot water storage tank unit 302 and flows into the heat pump unit 301 via the heat medium piping 304. After flowing into the heat pump unit 301, the heat medium is heated by the refrigerant in the liquid heat exchanger 2 and reaches a high temperature. This high-temperature heat medium flows out of the heat pump unit 301 and flows back into the hot water storage tank unit 302 via the heat medium piping 303. The heat medium then flows into the heating heat exchanger 8 via the three-way valve 7, where it exchanges heat with water, heating the water and lowering the temperature of the heat medium. This lowered-temperature heat medium then flows back into the heat medium pump 6.

[0043] In the hot water storage circuit 53, water flowing out from connection point 14 of the hot water storage tank 10 is sent to the heating heat exchanger 8 by the water pump 9. This water is heated by the heat medium in the heating heat exchanger 8 to become hot water. The hot water flowing out from the heating heat exchanger 8 flows into the hot water storage tank 10 from connection point 17 and is stored there. As water continuously flows out from connection point 14 of the hot water storage tank 10 and hot water continuously flows into connection point 17, the water temperature in the hot water storage tank 10 increases. In the hot water supply operation mode, no heating or cooling of the room is performed, and no heat medium flows through the air conditioning unit 305.

[0044] The operating states of the heat medium pump 6 and the water pump 9 are controlled by the hydro control means 127 of the hydro control device 121. Specifically, for example, the rotation speeds of the heat medium pump 6 and the water pump 9 are determined to be set respectively. The set rotation speeds of the heat medium pump 6 and the water pump 9 are set, for example, by operating the remote control device 251.

[0045] As described above, water heated by the heating heat exchanger 8 flows into the hot water storage tank 10 through the connection point 17 at the bottom of the hot water storage tank 10. Low-temperature water exists at the bottom of the hot water storage tank 10. As the water heated by the heating heat exchanger 8 flows into the hot water storage tank 10, the water temperature of the entire hot water storage tank 10 increases. The hot water supply operation in this embodiment gradually increases the temperature of the entire hot water storage tank 10, and hot water accumulates in the hot water storage tank 10 through multiple heat exchanges in the heating heat exchanger 8. This heating method is called circulating heating. In circulating heating, the water is heated by, for example, 5°C in the heating heat exchanger 8, thereby increasing the water temperature in the hot water storage tank 10. Therefore, the temperature of the water flowing into the heating heat exchanger 8 increases, for example, to 25°C, 30°C, etc., and the temperature of the water flowing out of the heating heat exchanger 8 also increases accordingly, for example, to 30°C, 35°C, etc. In circulating heating, at the beginning of heating, the water temperature in the hot water storage tank 10 is low, and the temperatures of the heat medium flowing into the heating heat exchanger 8 and the water flowing out of the heating heat exchanger 8 are also low, so the temperatures of the heat medium flowing out of the liquid heat exchanger 2 and the heat medium flowing into the liquid heat exchanger 2 are low. Therefore, the operating efficiency of the heat pump unit 301 is high.

[0046] The water pump 9 is controlled as follows. In order to keep the temperature of the heat medium flowing into the heating heat exchanger 8 low, the water flow rate is increased to lower the temperature of the water flowing out of the heating heat exchanger 8. In other words, the water pump 9 is operated at a constant flow rate, for example, so that the temperature difference between the water inlet and outlet of the heating heat exchanger 8 is about 5°C. For example, if the heating capacity of the heating heat exchanger 8 is 9 kW, the specific heat of water is 4.18 kJ / kgK, and the density of water is 1000 kg / m3, the required water flow rate is 25.84 liters / minute. Therefore, a pump that can ensure a flow rate of 25.84 liters / minute is selected as the water pump 9.

[0047] In the heat medium pump 6, too, a flow rate of the heat medium equal to or greater than the flow rate of water must be ensured in order to make the temperature difference between the inlet and outlet of the heat medium equal to or less than the temperature difference between the inlet and outlet of the water in the heating heat exchanger 8. In other words, if the flow rate of water delivered by the water pump 9 is 25.84 liters / minute, a pump capable of ensuring a flow rate of 25.84 liters / minute or more must be selected as the heat medium pump 6.

[0048] The high-pressure liquid refrigerant temperature is the temperature of the refrigerant flowing through the refrigerant circuit 51 at the outlet of the liquid heat exchanger 2. In controlling the expansion valve 3 of the heat pump unit 301, a target value for the high-pressure liquid refrigerant temperature is set according to either the temperature of the heat medium flowing into the liquid heat exchanger 2 or the temperature of the heat medium flowing out of the liquid heat exchanger 2, and the expansion valve 3 is controlled so that the high-pressure liquid refrigerant temperature reaches the target value. The target value for the high-pressure liquid refrigerant temperature can be, for example, 3°C higher than the temperature of the heat medium flowing into the liquid heat exchanger 2. Furthermore, because the heat medium pump 6 is controlled so that the temperature difference between the inlet and outlet of the heat medium in the heating heat exchanger 8 is approximately 5°C, the temperature difference between the inlet and outlet of the heat medium in the liquid heat exchanger 2 is also approximately 5°C. Therefore, because the temperature of the heat medium flowing into the liquid heat exchanger 2 is not so low, the expansion valve 3 may be controlled so that the degree of subcooling of the liquid heat exchanger 2 reaches a target value (e.g., 2°C). Here, the degree of subcooling of liquid heat exchanger 2 is a value obtained by subtracting the temperature detected by temperature sensor 203 from the saturation temperature of the pressure detected by pressure sensor 201 .

[0049] By doing as described above, the heat pump system 100 can perform chilled water cooling operation, hot water heating operation, and hot water supply operation, and can perform hot water supply operation with high efficiency. Specifically, by using the heating heat exchanger 8 installed outside the hot water storage tank 10, heat transfer performance is improved. Since the temperature of the heat medium flowing into the heat pump unit 301 can be lowered, the heat pump unit 301 can be operated with high operating efficiency. Furthermore, because the heating heat exchanger 8 is installed outside the hot water storage tank 10, it can be easily replaced if a malfunction occurs in the heating heat exchanger 8, thereby improving maintainability.

[0050] In this embodiment, the heating capacity of the heat pump unit 301 corresponds to the capacity of the refrigeration cycle device. The hydro control device 121 can calculate the heating capacity [kW] of the heat pump unit 301 using the following formula based on the outlet water temperature detected by the temperature sensor 208, the inlet water temperature detected by the temperature sensor 209, and the flow rate of the heat medium detected by the flow sensor 131. The specific heat of the heat medium and the density of the heat medium are stored in the storage means 123. Heating capacity = Heat medium flow rate × Heat medium specific heat × Heat medium density × (Outlet water temperature - Inlet water temperature)

[0051] In this embodiment, the seventh temperature sensor 208, the eighth temperature sensor 209 and the flow sensor 131 correspond to a capacity detector that detects the capacity of the refrigeration cycle device.

[0052] The heat pump system 100 further includes an electric heater 60. The electric heater 60 is provided in the hot water storage tank 10 of the hot water storage tank unit 302. In the configuration example described here, two electric heaters 60, a first electric heater 61 and a second electric heater 62, are provided. However, the number of electric heaters 60 is not limited to two, and may be one or more. In the present disclosure, when the first electric heater 61 and the second electric heater 62 are referred to collectively without distinction, they are referred to as electric heaters 60.

[0053] The electric heater 60 can heat the hot water in the hot water storage tank 10 using power supplied from the distribution board 430, i.e., one or both of the power generated by the solar power generation device 400 and commercial power, without relying on the heat source of the heat pump unit 301. The operation of the electric heater 60 is controlled by the hydro control means 127 of the hydro control device 121.

[0054] The second electric heater 62 is provided below the first electric heater 61. In particular, it is preferable to place the second electric heater 62 below the center in the height direction of the hot water storage tank 10. In this way, the low-temperature hot water in the lower part of the hot water storage tank 10 can be efficiently heated by the second electric heater 62. In the illustrated example, the first electric heater 61 is located at the center in the height direction of the hot water storage tank 10.

[0055] Furthermore, it is preferable that the hydro control means 127 be able to individually and independently control the operation of each of the first electric heater 61 and the second electric heater 62. In this way, the heating capacity of the electric heater 60 can be changed depending on the situation. In addition to individually controlling each of the multiple electric heaters 60, the heating capacity of the electric heater 60 may be made variable by inverter controlling the electric heater 60 or by changing the voltage value applied to the electric heater 60.

[0056] The heat pump system 100 of this embodiment is capable of performing a first hot water supply operation and a second hot water supply operation. The first hot water supply operation is an operation that supplies hot water in the hot water supply operation mode described above. That is, the first hot water supply operation is a hot water supply operation that uses the heat pump unit 301 as a heat source. The second hot water supply operation is an operation that heats hot water in the hot water storage tank 10 using the electric heater 60.

[0057] In this embodiment, the hydro control means 127 performs the first hot water supply operation until the temperature of the hot water in the hot water storage tank 10 reaches the first set temperature. That is, the hydro control device 121 performs the first hot water supply operation using the heat pump unit 301, which is a heat source machine, as the heat source until the temperature of the hot water in the hot water storage tank 10 reaches the first set temperature. Here, the first set temperature is, for example, a temperature that is set in advance.

[0058] Furthermore, the hydro control means 127 executes the second hot water supply operation when the air conditioning unit 305 is in air conditioning operation using the heat pump unit 301 as a heat source and the power generated by the solar power generation device 400 is equal to or greater than the reference power. In this case, the hydro control means 127 executes the second hot water supply operation until the temperature of the hot water in the hot water storage tank 10 reaches a second set temperature. The second set temperature is a temperature obtained by adding an additional value to the first set temperature. That is, when the air conditioning unit 305 is in air conditioning operation using the heat pump unit 301, which is a heat source machine, as a heat source and the power generated by the solar power generation device 400 is equal to or greater than the reference power, the hydro control device 121 executes the second hot water supply operation in which the electric heater 60 heats the hot water in the hot water storage tank 10 until the temperature of the hot water in the hot water storage tank 10 reaches a second set temperature obtained by adding the additional value to the first set temperature. Note that the additional value is a positive value. For example, the second set temperature is set to the maximum temperature (e.g., 90°C) that can be set as the water temperature in the hot water storage tank 10. In this case, the first set temperature is set to a temperature (e.g., 70°C) that is lower than the maximum temperature that can be set as the water temperature in the hot water storage tank 10.

[0059] The hydro control device 121 can acquire information about the power generated by the solar power generation device 400, for example, by acquiring the measurement results of a power meter (not shown) connected to the distribution board 430 or built into the distribution board 430. Furthermore, as shown in FIG. 3 , the hydro control device 121 may be able to communicate with a power information terminal 440. The power information terminal 440 is connected to the distribution board 430. The hydro control device 121 may then acquire information about the power generated by the solar power generation device 400 via the power information terminal 440.

[0060] The heat pump system 100 configured as described above efficiently stores heat in the hot water storage tank 10 using the power generated by the solar power generation device 400, thereby suppressing the reverse flow of power to the power company's grid. In addition, the air conditioning operation of the air conditioning unit 305, which uses the heat pump unit 301 as a heat source, and the storage of heat in the hot water storage tank 10 can be performed simultaneously.

[0061] In this embodiment, in particular, the hydro control means 127 of the hydro control device 121 may be configured to perform the first hot water supply operation when the power generated by the solar power generation device 400 is less than the aforementioned reference power and the temperature of the hot water in the hot water storage tank 10 is equal to or lower than the hot water supply operation start temperature. Here, the hot water supply operation start temperature is set to a temperature that is lower by a certain temperature than the aforementioned first set temperature, for example. Then, the hydro control means 127 of the hydro control device 121 may be configured to perform the second hot water supply operation when the power generated by the solar power generation device 400 is equal to or higher than the aforementioned reference power and the temperature of the hot water in the hot water storage tank 10 is lower than the aforementioned second set temperature.

[0062] Alternatively, even if the power generated by the solar power generation device 400 is equal to or greater than the aforementioned reference power, if the air conditioning unit 305 is not in air conditioning operation using the heat pump unit 301, which is a heat source machine, as a heat source, the hydro control means 127 may be configured to perform the first hot water supply operation.

[0063] Furthermore, the hydro control means 127 of the hydro control device 121 may be configured to perform the second hot water supply operation when the air conditioning unit 305 is operating in chilled water cooling mode, particularly using the heat pump unit 301 as a heat source. By doing so, the hot water in the hot water storage tank 10 can be efficiently heated using the power generated by the solar power generation device 400 during the summer cooling season when there is a lot of solar radiation.

[0064] In this embodiment, the hydro control means 127 of the hydro control device 121 may change the second set temperature in response to user input. In this case, the user inputs a desired temperature as the second set temperature, for example, by operating the remote control device 251, the power information terminal 440, or the like. The hydro control means 127 sets the second set temperature in response to the input via the remote control device 251, the power information terminal 440, or the like. If the user wants to prioritize use of the power generated by the solar power generation device 400 for other devices in the home (for example, if the user wants to store some surplus power in a storage battery for air conditioning at night), the user can lower the second set temperature to allow the power generated by the solar power generation device 400 to be used by other devices in the home.

[0065] As described above, if the heating capacity of the electric heater 60 is variable, the hydro control means 127 of the hydro control device 121 may change the heating capacity of the electric heater 60 in accordance with the second set temperature. For example, the higher the second set temperature, the higher the heating capacity of the electric heater 60, and conversely, the lower the second set temperature, the lower the heating capacity of the electric heater 60. In this way, the hot water in the hot water storage tank 10 can be efficiently heated by the electric heater 60 in accordance with the second set temperature.

[0066] The hydro control means 127 of the hydro control device 121 may acquire information about surplus power generated by the solar power generation device 400 and may perform the second hot water supply operation when the surplus power is equal to or greater than the power consumption of the electric heater 60. Here, the surplus power generated by the solar power generation device 400 is the difference between the power generated by the solar power generation device 400 and the total power consumption of the devices supplied with power from the distribution panel 430 when the power generated by the solar power generation device 400 is greater than the total power consumption of the devices supplied with power from the distribution panel 430. In many cases, the total power consumption of the devices supplied with power from the distribution panel 430 can be rephrased as the total power consumption of the building in which the heat pump system 100 is installed. The hydro control device 121 can acquire information about surplus power generated by the solar power generation device 400, for example, via the aforementioned power information terminal 440. In this way, use of the electric heater 60 can be suppressed when the surplus power is smaller than the heater power consumption, thereby preventing increases in commercial power usage fees.

[0067] Furthermore, as described above, if the heating capacity of the electric heater 60 is variable, the hydro control means 127 of the hydro control device 121 may change the heating capacity of the electric heater 60 according to the surplus power generated by the solar power generation device 400. For example, the greater the surplus power, the higher the heating capacity of the electric heater 60, and conversely, the lower the surplus power, the lower the heating capacity of the electric heater 60. In this way, the hot water in the hot water storage tank 10 can be efficiently heated by the electric heater 60 according to the surplus power.

[0068] Next, an example of the operation of the heat pump system 100 configured as described above will be described with reference to the flow charts of Figures 7 and 8. In step S11 of Figure 7, the heat pump control means 105 of the heat pump control device 101 and the hydro control means 127 of the hydro control device 121 start chilled water cooling operation by the air conditioning unit 305 using the heat pump unit 301 as a heat source. In the following step S12, the hydro control means 127 determines whether the surplus power generated by the solar power generation device 400 is equal to or greater than the capacity of the electric heater 60, i.e., the power consumption. If the surplus power generated by the solar power generation device 400 is equal to or greater than the capacity of the electric heater 60, the hydro control means 127 then performs the process of step S13.

[0069] In step S13, the hydro control means 127 starts a second hot water supply operation in which the electric heater 60 heats the hot water in the hot water storage tank 10. In the following step S14, the hydro control means 127 again determines whether the surplus power generated by the solar power generation device 400 is equal to or greater than the capacity, i.e., the power consumption, of the electric heater 60. If the surplus power generated by the solar power generation device 400 is not equal to or greater than the capacity of the electric heater 60, the hydro control means 127 then performs the process of step S15.

[0070] In step S15, the hydro control means 127 ends the second hot water supply operation. After step S15, the hydro control means 127 then performs the processing of step S16. In step S16, the hydro control means 127 determines whether the chilled water cooling operation of the air conditioning unit 305 has ended. If the chilled water cooling operation of the air conditioning unit 305 has ended, the series of processing ends. On the other hand, if the chilled water cooling operation of the air conditioning unit 305 has not ended, the processing returns to step S12 to continue.

[0071] If it is determined in step S14 that the surplus power generated by the solar power generation device 400 is equal to or greater than the capacity of the electric heater 60, the hydro control means 127 then performs the process of step S17. In step S17, the hydro control means 127 determines whether the temperature of the hot water in the hot water storage tank 10 is equal to or greater than the second set temperature, i.e., equal to or greater than the temperature obtained by adding the additional value to the first set temperature. If the temperature of the hot water in the hot water storage tank 10 is equal to or greater than the second set temperature, the hydro control means 127 then performs the process of step S15. On the other hand, if the temperature of the hot water in the hot water storage tank 10 is not equal to or greater than the second set temperature, the hydro control means 127 then performs the process of step S16.

[0072] Furthermore, in the second hot water supply operation, the hydro control means 127 executes the process shown in Fig. 8. That is, in step S21 of Fig. 8, the hydro control means 127 determines whether the surplus power generated by the solar power generation device 400 is equal to or greater than the total capacity of the electric heater 60, i.e., the sum of the power consumption of the first electric heater 61 and the power consumption of the second electric heater 62. If the surplus power generated by the solar power generation device 400 is equal to or greater than the total capacity of the electric heater 60, the hydro control means 127 then executes the process of step S22. In step S22, the hydro control means 127 operates both the first electric heater 61 and the second electric heater 62 simultaneously.

[0073] On the other hand, if the surplus power generated by the solar power generation device 400 is not equal to or greater than the total capacity of the electric heaters 60 in step S21, the hydro control means 127 then performs the process of step S23. In step S23, the hydro control means 127 operates only the second electric heater 62.

[0074] After step S22 or step S23, the hydro control means 127 then performs the process of step S24. In step S24, the hydro control means 127 determines whether the second hot water supply operation has ended. If the second hot water supply operation has ended, the series of processes ends. On the other hand, if the second hot water supply operation has not ended, the process returns to step S21 and continues.

[0075] Next, an example of a change in the operating state of the heat pump system 100 configured as described above will be described with reference to FIG. 9 . When the water temperature in the hot water storage tank 10 drops below the hot water supply operation start temperature, such as early in the morning, the first hot water supply operation is performed in preference to the chilled water cooling operation and the hot water heating operation. If the amount of solar radiation increases during the day and the surplus power generated by the solar power generation device 400 exceeds the electric heater power threshold (e.g., the capacity value of the electric heater 60), the second hot water supply operation is started even if the tank water temperature has not yet dropped to the hot water supply operation start temperature. Then, when the amount of solar radiation decreases in the evening and the surplus power generated by the solar power generation device 400 falls below the electric heater power threshold, the second hot water supply operation is terminated.

[0076] FIG. 10 shows another example of the heat pump system 100 according to this embodiment. The configuration examples described above are so-called indirect air conditioning and hot water supply systems that include a heat medium circulation circuit 52 and a hot water storage circuit 53 in addition to a refrigerant circuit 51. In contrast, the configuration example shown in FIG. 10 performs air conditioning and hot water supply using only the refrigerant circuit 51. In the configuration example shown in FIG. 10, hot water in the hot water storage tank 10 is heated by winding refrigerant piping around the hot water storage tank 10. This other example of the heat pump system 100 can also perform the first and second hot water supply operations described above. Furthermore, the conditions for performing the first and second hot water supply operations are the same as those described above. Therefore, heat can be efficiently stored in the hot water storage tank 10 using power generated by the solar power generation device 400, thereby suppressing reverse power flow to the electric power company's grid. Furthermore, air conditioning operation of the air conditioning unit 305 using the heat pump unit 301 as a heat source and heat storage in the hot water storage tank 10 can be performed simultaneously.

[0077] FIG. 11 is a diagram showing an example of a configuration for realizing the respective functions of the heat pump control device 101 and the hydro control device 121 in this embodiment. The respective functions of the heat pump control device 101 and the hydro control device 121 are realized, for example, by a processing circuit. The processing circuit may include a processor 601 and a memory 602. The processing circuit may also be dedicated hardware 600. A portion of the processing circuit may be formed as dedicated hardware 600, and the processing circuit may further include a processor 601 and a memory 602. In the example shown in the figure, a portion of the processing circuit is formed as dedicated hardware 600. Furthermore, in the example shown in the figure, the processing circuit further includes a processor 601 and a memory 602.

[0078] The processing circuitry, part of which is at least one dedicated hardware 600, may be, for example, a single circuit, a multiple circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof. If the processing circuitry comprises at least one processor 601 and at least one memory 602, the functionality of the control device 30 may be realized by software, firmware, or a combination of software and firmware.

[0079] The software and firmware are written as programs and stored in memory 602. The processor 601 realizes the functions of each unit by reading and executing the programs stored in memory 602. The processor 601 is also called a CPU (Central Processing Unit), central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, or DSP. The memory 602 may be, for example, a non-volatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM, or EEPROM, or a magnetic disk, flexible disk, optical disk, compact disk, minidisk, DVD, etc.

[0080] In this way, the processing circuits of the heat pump control device 101 and the hydro control device 121 can realize each function of the control device 30 by hardware, software, firmware, or a combination of these. When the processing circuit of the control device 30 includes at least a processor 601 and a memory 602, the processor 601 executes a program stored in the memory 602 in the control device 30, and the hardware and software of the control device 30 work together to realize the functions of each part of the heat pump control device 101 and the hydro control device 121. Note that the air conditioning and hot water supply system is not limited to a configuration in which operation is controlled by a single heat pump control device 101 and a single hydro control device 121. The operation of the air conditioning and hot water supply system may be controlled by multiple devices working together.

[0081] The present disclosure can be used in an air conditioning and hot water supply system that includes a heat source machine that is supplied with power generated by a solar power generation device and has a refrigeration cycle, an air conditioning device that performs air conditioning using the heat source machine as a heat source, and a hot water storage unit that has a hot water storage tank that stores heated hot water.

[0082] REFERENCE SIGNS LIST 1 Compressor 2 Liquid heat exchanger 3 Expansion valve 4 Heat source heat exchanger 5 Blower 6 Heat medium pump 7 Three-way valve 8 Heating heat exchanger 9 Water pump 10 Hot water storage tank 11 Mixing valve 12 Air conditioning heat exchanger 12a First air conditioning heat exchanger 12b Second air conditioning heat exchanger 14 First connection point 15 Hot water outlet pipe 17 Second connection point 21 Four-way valve 51 Refrigerant circuit 52 Heat medium circulation circuit 53 Hot water storage circuit 60 Electric heater 61 First electric heater 62 Second electric heater 100 Heat pump system 101 Heat pump control device 102 Heat pump measurement means 103 Heat pump communication means 104 Heat pump calculation means 105 Heat pump control means 121 Hydro control device 122 Hydro measurement means 123 Storage means 124 Input means 125 Hydro communication means 126 Hydro calculation means 127 Hydro control means 131 Flow sensor 141 Wattmeter 201 Pressure sensor 202 First temperature sensor 203 Second temperature sensor 204 Third temperature sensor 205 Fourth temperature sensor 206 Fifth temperature sensor 207 Sixth temperature sensor 208 Seventh temperature sensor 209 Eighth temperature sensor 210 Ninth temperature sensor 211 Tenth temperature sensor 212 Eleventh temperature sensor 216 Twelfth temperature sensor 251 Remote control device 301 Heat pump unit 302 Hot water storage tank unit 303 First heat medium piping 304 Second heat medium piping 305 Air conditioning unit 305a First air conditioning unit 305b Second air conditioning unit 306 Third heat medium piping 307 Fourth heat medium piping 308 Hot water supply pipe 309 Water supply pipe 400 Photovoltaic power generation device 410 Connection member 420 Power conditioner 430 Distribution board 440 Power information terminal 600 Dedicated hardware 601 Processor 602 Memory

Claims

1. An air conditioning and hot water supply system comprising: a heat source machine having a refrigeration cycle; an air conditioning device that performs air conditioning using the heat source machine as a heat source; a hot water storage unit having a hot water storage tank that stores heated hot water; a control device that performs a first hot water supply operation using the heat source machine as a heat source until the temperature of the hot water in the hot water storage tank reaches a first set temperature; and an electric heater that heats the hot water in the hot water storage tank, wherein when the air conditioning device is performing air conditioning operation using the heat source machine as a heat source and the power generation output of a solar power generation device is equal to or higher than a reference power, the control device performs a second hot water supply operation in which the electric heater heats the hot water in the hot water storage tank until the temperature of the hot water in the hot water storage tank reaches a second set temperature obtained by adding an additional value to the first set temperature.

2. The air conditioning and hot water supply system of claim 1, wherein the control device performs the first hot water supply operation when the power generated by the solar power generation device is less than the reference power and the temperature of the hot water in the hot water storage tank is below the hot water supply operation start temperature, and performs the second hot water supply operation when the power generated by the solar power generation device is equal to or greater than the reference power and the temperature of the hot water in the hot water storage tank is below the second set temperature.

3. An air conditioning and hot water supply system according to claim 1 or claim 2, wherein the air conditioning operation is chilled water cooling operation.

4. An air conditioning and hot water supply system as described in any one of claims 1 to 3, wherein the electric heater comprises a first electric heater and a second electric heater arranged below the first electric heater, and the second electric heater is arranged below the center of the hot water storage tank in the vertical direction.

5. An air conditioning and hot water supply system according to any one of claims 1 to 4, wherein the control device changes the second set temperature in response to a user input.

6. The air conditioning and hot water supply system according to claim 5, wherein the control device changes the heating capacity of the electric heater in accordance with the second set temperature.

7. An air conditioning and hot water supply system as described in any one of claims 1 to 5, wherein the control device obtains surplus electricity generated by the solar power generation device and, when the surplus electricity is greater than or equal to the power consumption of the electric heater, performs the second hot water supply operation.

8. The air conditioning and hot water supply system according to claim 7, wherein the control device changes the heating capacity of the electric heater in accordance with the surplus power.

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