JP2016080248A - Hot water system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water system capable of reducing an opportunity of using a combustion type heating device.SOLUTION: A hot water system 1 comprises: a heat pump device 200 for heating water in a hot water storage tank 100; a combustion type heating device 300 for heating hot-water supply water; a power supply adjuster 400 for changing-over a power supply for the heat pump device 200 into one or two or more combinations of a commercial power supply 403, a solar heat power generator 401, and a battery cell 402; and control means (control device 500) for selecting, as a candidate for a power supply for the heat pump device 200, a combination of one or two or more of the commercial power supply 403, the solar heat power generator 401, and the battery cell 402 in response to electrical power that can be supplied from the solar heat power generator 401 to the heat pump device 200 and power storage amount of the battery cell 402, and changing a threshold of hot water storage amount applied as a starting point for energizing the heat pump device 200 when the stored hot water amount is reduced during the stop of the heat pump device 200 in response to a configuration of the candidate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hot water supply system including a heat pump device that heats water in a hot water storage tank and a combustion heating device that heats water for hot water supply.

  A hybrid hot water supply system including both a heat pump device and a combustion heating device is known. In general, the heat pump device can reduce the running cost as compared with the combustion heating device, but has a small heating capacity. Therefore, it is common to use the heat pump device in a time zone where the unit price of electricity is low, store hot water in a hot water storage tank, and prepare for hot water supply demand.

  In the hot water supply system disclosed in Patent Document 1 below, in a first time zone including nighttime, a predetermined amount of hot water is heated by a heat pump hot water supply means (heat pump device) and stored in a hot water storage tank. If the amount of hot water stored in the hot water storage tank is greater than or equal to the predetermined first hot water storage amount during two hours, hot water is supplied only from the hot water storage tank to the hot water supply load. If it falls below, hot water heating by the heat pump hot water supply means is added, and if the amount of hot water stored in the hot water storage tank falls below a predetermined second hot water storage amount less than the first hot water storage amount in the second time zone, auxiliary hot water supply means (combustion heating device) Add hot water by.

  In Patent Document 2 below, in a heat pump hot water supply system that operates a heat pump water heater using electric energy stored in a storage battery, the amount of power generated on the next day of the solar power generation device and the power demand of electric equipment other than the heat pump water heater are predicted. Compare the surplus amount of power generation minus the power demand with the amount of power required by the heat pump water heater the next day. An invention for controlling to store electricity is disclosed.

  The hybrid hot water supply system disclosed in Patent Document 3 below corresponds to the water supply temperature and the outside air temperature by referring to the COP table in which the COP of the heat pump type water heater (heat pump device) is stored according to the conditions of the water supply temperature and the outside air temperature. The COP is obtained, and the obtained COP is compared with the COP threshold value at which the heat pump type water heater is operated more efficiently than the combustion type water heater (combustion type heating device). And a control unit for operating one of the combustion water heaters.

JP 2006-349201 A JP 2011-69587 A JP 2011-12941 A

  In a hot water supply system including both a heat pump device and a combustion heating device, hot water can be supplied by operating a combustion heating device having a high heating capacity even when the hot water in the hot water storage tank is exhausted. For this reason, since the amount of hot water stored in the hot water storage tank can be suppressed at night time when the power unit price is low, the operating cost of the heat pump device and the heat dissipation loss from the hot water storage tank can be suppressed. However, when the amount of hot water used is large, there is a risk that the operating cost of the entire system will increase due to the increased use opportunities of the combustion-type heating device having a high operating cost.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a hot water supply system that can reduce the use opportunity of a combustion heating device.

  A hot water supply system according to the present invention includes a hot water storage tank for storing hot water supply water, hot water storage amount detecting means for detecting the amount of hot water stored in the hot water storage tank, a heat pump device for heating the water in the hot water storage tank, and combustion heating for heating the hot water supply water. And a power supply regulator that switches a power source that supplies power to the heat pump device to a commercial power source, a solar power generation device, and a combination including two or more power storage devices, and the solar power generation device to the heat pump device Depending on the power that can be supplied to the battery and the amount of power stored in the power storage device, a commercial power source, a solar power generation device, and a combination including one or more power storage devices can be used as power source candidates for supplying power to the heat pump device. Select the threshold for the hot water storage amount that triggers the heat pump device to start when the hot water storage amount decreases while the heat pump device is stopped. Flip control means to change, in which comprises a.

  According to the hot water supply system of the present invention, it is possible to reduce the opportunity to use the combustion heating device.

It is a block diagram which shows the hot water supply system of Embodiment 1 of this invention. It is a functional block diagram of the control apparatus with which the hot water supply system 1 of Embodiment 1 of this invention is provided. It is a flowchart which shows the control action (boiling judgment process) which a control apparatus performs in Embodiment 1 of this invention. It is a flowchart which shows the control operation | movement (starting judgment process of a combustion type heating apparatus) which a control apparatus performs in Embodiment 1 of this invention. It is a flowchart which shows the control operation (power supply state determination process) which a control apparatus performs in Embodiment 1 of this invention. It is a schematic diagram of the look-up table which described heat pump prediction electric power Ee based on heat pump incoming water temperature Tw and external temperature DB. It is a flowchart which shows the control operation (power supply switching process) which a control apparatus performs in Embodiment 1 of this invention via a power supply regulator. It is a graph which shows transition of the amount of hot water storage in the daytime time slot | zone at the time of using the hot water supply system of a comparative example, and a cumulative hot water supply load. It is a graph which shows transition of the amount of hot water storage and accumulation hot water supply load in the daytime time slot | zone (time slot | zone (2)) at the time of utilizing the hot water supply system of Embodiment 1 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted. In this specification, “water” is a concept including water of all temperatures from low-temperature cold water to high-temperature hot water.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram illustrating a hot water supply system according to Embodiment 1 of the present invention. A hot water supply system 1 according to the first embodiment shown in FIG. 1 includes a hot water storage tank 100, a heat pump device 200, a combustion heating device 300, a power conditioner (power conditioner) 400, and a control device 500. Hot water supply water is stored in the hot water storage tank 100. In the hot water storage tank 100, a temperature stratification in which the upper side is high-temperature water and the lower side is low-temperature water can be formed due to the difference in water density due to the temperature difference.

  An upper temperature sensor 101, a middle temperature sensor 102, a lower temperature sensor 103, and a lowermost temperature sensor 104 that detect the surface temperature of the hot water storage tank 100 are attached to the surface of the hot water storage tank 100. The upper temperature sensor 101 is attached at a position above an intermediate point in the height direction of the hot water storage tank 100. The middle temperature sensor 102 is attached to the intermediate point in the height direction of the hot water storage tank 100 or a position in the vicinity thereof. The lower temperature sensor 103 is attached at a position below the intermediate point in the height direction of the hot water storage tank 100. The lowest temperature sensor 104 is attached to the lowest position of the hot water storage tank 100. By detecting the temperature distribution in the vertical direction in the hot water storage tank 100 by these four temperature sensors 101, 102, 103, 104, the amount of hot water stored in the hot water storage tank 100 can be detected. In the first embodiment, the temperature sensors 101, 102, 103, and 104 correspond to hot water storage amount detection means. The number of temperature sensors constituting the hot water storage amount detection means in the present invention is not limited to four, but may be five or more or three.

  A water supply port 106 provided in the hot water supply system 1 is connected to a water source such as a water supply for supplying hot water. A water supply pipe 107 communicating with the water supply port 106 is connected to the lower part of the hot water storage tank 100. The water supplied to the water supply port 106 flows into the lower part of the hot water storage tank 100 through the water supply pipe 107, so that the hot water storage tank 100 is always maintained in a full state. The upper part of hot water storage tank 100 is connected to hot water supply terminal 600 through hot water supply pipe 110. The hot water supply terminal 600 is, for example, a bathtub, a shower, a faucet, or the like. The hot water supply pipe 110 is provided with a hot water supply flow rate sensor 601 that detects the flow rate of hot water sent to the hot water supply terminal 600. When hot water is supplied from the hot water storage tank 100 to the hot water supply terminal 600, the hot water stored in the hot water storage tank 100 is sent out to the hot water supply pipe 110 by the water pressure of the water source acting on the hot water storage tank 100 from the water supply pipe 107.

  The heat pump apparatus 200 includes a refrigerant circuit. The refrigerant circuit includes a compressor that compresses the refrigerant, a water-refrigerant heat exchanger, a decompression device that decompresses the refrigerant, and low-temperature side heat that causes the refrigerant to absorb heat from a low-temperature heat source (outside air in the first embodiment). It includes an exchanger (evaporator) and refrigerant piping that connects these devices in an annular shape. The heat pump apparatus 200 heats water by operating a heat pump cycle (refrigeration cycle) with this refrigerant circuit. The heat pump device 200 heats water by exchanging heat between the high-temperature and high-pressure refrigerant compressed by the compressor and water using a water-refrigerant heat exchanger.

  The lower part of the hot water storage tank 100 and the water inlet of the water-refrigerant heat exchanger of the heat pump device 200 are connected via a water channel 108. A water pump 105 that sends water from the lower part of the hot water storage tank 100 to the heat pump device 200 is installed in the middle of the water channel 108. A water outlet of the water-refrigerant heat exchanger of the heat pump device 200 and the upper part of the hot water storage tank 100 are connected via a water channel 109.

  By operating the heat pump device 200 and the water pump 105, the amount of hot water stored in the hot water storage tank 100 can be increased. This operation is hereinafter referred to as “HP boiling”. In the HP boiling, water in the lower part of the hot water storage tank 100 is led to the water-refrigerant heat exchanger of the heat pump device 200 through the water channel 108 and heated. The heated hot water flows into the upper part of the hot water storage tank 100 through the water channel 109. As the water circulates between the hot water storage tank 100 and the heat pump device 200 in this way, hot water gradually accumulates from the top to the bottom in the hot water storage tank 100, and the amount of stored hot water increases.

  The combustion heating device 300 heats hot water supply water by burning, for example, gas, kerosene, heavy oil, coal, or other fuel. A water supply pipe 111 leading to the water supply port 106 is connected to the water inlet of the combustion heating apparatus 300. One end of a hot water supply pipe 112 is connected to the water outlet of the combustion heating apparatus 300. The other end of the hot water supply pipe 112 communicates with the hot water supply pipe 110 between the upper part of the hot water storage tank 100 and the hot water supply flow rate sensor 601. When the hot water supply water is heated by the combustion type heating device 300, the water supplied to the water supply port 106 is sent to the combustion type heating device 300 through the water supply pipe 111, and the hot water heated by the combustion type heating device 300 is supplied. The hot water supply pipe 112 and the hot water supply flow rate sensor 601 are sent to the hot water supply terminal 600.

  The heat pump device 200 is driven by electric power supplied from at least one of the solar power generation device 401, the power storage device 402, and the commercial power source 403. The power conditioner 400 is connected to the solar power generation device 401 via the power line 404, connected to the power storage device 402 via the power line 405, connected to the commercial power source 403 via the power line 406, and heat pump via the power line 407. It is connected to the device 200. The power conditioner 400 can switch the power source that supplies power to the heat pump device 200 to one of the commercial power source 403, the solar power generation device 401, and the power storage device 402, or a combination including two or more. The power conditioner 400 can convert DC power supplied from at least one of the solar power generation device 401 and the power storage device 402 into AC power and supply the AC power to the heat pump device 200. The power conditioner 400 can also supply the AC power thus converted and the AC power supplied from the commercial power supply 403 to the heat pump apparatus 200. The power storage device 402 includes a storage battery, a capacitor, and the like. The power conditioner 400 can cause the power storage device 402 to store the power generated by the solar power generation device 401. When the generated power of the solar power generation apparatus 401 is surplus, the power conditioner 400 converts the direct current power generated by the solar power generation apparatus 401 into alternating current power, and is connected to the power system of the commercial power supply 403. Reverse power flow can be performed.

  The control device 500 corresponds to control means for controlling the entire hot water supply system 1. The control device 500 includes a storage unit including a ROM (Read Only Memory), a RAM (Random Access Memory), and a nonvolatile memory, and a CPU (Central Processing Unit) that executes arithmetic processing based on a program stored in the storage unit. ) And an input / output port for inputting / outputting external signals to / from the CPU. Actuators and sensors provided in the hot water supply system 1 (upper temperature sensor 101, middle temperature sensor 102, lower temperature sensor 103, lowest temperature sensor 104, water pump 105, heat pump device 200, outside air temperature sensor 201, combustion heating device 300 , And a user interface device (not shown) such as a remote controller are electrically connected to the control device 500. The control device 500 controls the operation of the hot water supply system 1 based on detection values of sensors, signals from the user interface device, and the like.

  The control device 500 is one of the commercial power supply 403, the solar power generation device 401, and the power storage device 402 according to the power that can be supplied from the solar power generation device 401 to the heat pump device 200 and the power storage amount of the power storage device 402. Or a combination including two or more is selected as a power source candidate for supplying power to the heat pump apparatus 200 (hereinafter referred to as a “heat pump power source candidate”). In the first embodiment, the control device 500 can detect the power that can be supplied from the solar power generation device 401 to the heat pump device 200 and the value of the amount of power stored in the power storage device 402 via the power supply regulator 400.

  FIG. 2 is a functional block diagram of control device 500 provided in hot water supply system 1 of the first embodiment. As shown in FIG. 2, the control device 500 includes a hot water storage measuring unit 501, a boiling determination unit 502, and a power supply switching instruction unit 503. The hot water storage measuring unit 501 determines the current hot water storage amount of the hot water storage tank 100 based on the detected temperatures of the upper temperature sensor 101, the middle temperature sensor 102, the lower temperature sensor 103, and the lowermost temperature sensor 104. In the first embodiment, the hot water storage unit 501 determines the amount of hot water stored in the hot water storage tank 100 as follows. The hot water storage measuring unit 501 determines that the detected temperature is 60 ° C. or higher as hot water. When the temperature detected by the lowest temperature sensor 104 is 60 ° C. or higher, the hot water storage measuring unit 501 determines that the amount of stored hot water is A or higher. When the temperature detected by the lower temperature sensor 103 is 60 ° C. or higher and the temperature detected by the lowermost temperature sensor 104 is lower than 60 ° C., the hot water storage measuring unit 501 determines that the amount of stored hot water is B or higher (and less than A). . When the temperature detected by the middle temperature sensor 102 is 60 ° C. or higher and the temperature detected by the lower temperature sensor 103 is lower than 60 ° C., the hot water storage measuring unit 501 determines that the amount of stored hot water is C or higher (and less than B). When the temperature detected by the upper temperature sensor 101 is 60 ° C. or higher and the temperature detected by the middle temperature sensor 102 is lower than 60 ° C., the hot water storage measuring unit 501 determines that the hot water storage amount is D or higher (and less than C). Here, A to D are amounts of hot water that satisfy the relationship of A> B> C> D.

  The boiling determination unit 502 determines start and stop of HP boiling (start and stop of the heat pump device 200 and the water pump 105) and start and stop of combustion of the combustion type heating device 300. The power supply switching instruction unit 503 controls the power supply regulator 400 to switch the power supply that supplies power to the heat pump apparatus 200. FIG. 3 is a flowchart showing a control operation (boiling determination process) performed by control device 500 in the first embodiment. Below, with reference to FIG. 3, the process which the boiling judgment part 502 determines the start and stop of HP boiling is demonstrated first.

  When the boiling determination process is started in step S510, first, a startup determination process for the combustion heating apparatus 300 is performed in step S530, and a power state determination process is performed in step S540. The activation determination process of the combustion heating apparatus 300 in step S530 will be described later with reference to FIG. The power supply state determination process in step S540 will be described later with reference to FIG.

  Subsequently, in step S511, it is determined whether or not the current time is included in the time zone (1). If the current time is included in the time zone (1), the process proceeds to step S512. If the current time is not included in the time period (1), the process proceeds to step S513. The time zone (1) is a time zone in which the power demand of the commercial power source 403 is small in one day and the power unit price of the commercial power source 403 is lower than other time zones (for example, night time from 23:00 to 7:00) Obi).

  In step S512, when the hot water storage amount determined by the hot water metering unit 501 is greater than or equal to A, the process proceeds to step S517 to stop the HP boiling, and when the current hot water storage amount is less than A, step S518. The HP boiling is started after transitioning to. Thereafter, the process proceeds to operation S530.

  In step S513, it is determined whether or not the current time is included in the time zone (2). If the current time is included in the time zone (2), the process proceeds to step S514. If the current time is not included in the time period (2), the process proceeds to step S523. The time zone (2) is a time zone that does not overlap with the time zone (1) in the day, and is a daytime time zone in which the power unit price of the commercial power supply 403 is higher than the time zone (1). In the first embodiment, all the time zones that do not overlap with the time zone (1) in the day may be set as the time zone (2). In the first embodiment, a time zone other than the time zone (1) and the time zone (2) may be further set. When the process proceeds to step S523, that is, when the current time is not included in either the time zone (1) or the time zone (2), the HP boiling is stopped, and then the process proceeds to step S530.

  In step S514, it is determined whether the heat pump drive flag Fhp is ON or OFF. If the heat pump drive flag Fhp is ON, the process proceeds to step S515. If the heat pump drive flag Fhp is OFF, the process proceeds to step S516. In step S515, it is determined whether the current hot water storage amount is B or more. When the current hot water storage amount is B or more, the process proceeds to step S519 to stop the HP boiling, and when the current hot water storage amount is less than B, the process proceeds to step S520 to start the HP boiling. After step S519 or step S520, the process proceeds to step S530.

  In step S516, it is determined whether the current hot water storage amount is C or more. When the current hot water storage amount is C or more, the process proceeds to step S521 to stop the HP boiling, and when the current hot water storage amount is less than C, the process proceeds to step S522 to start the HP boiling. After step S521 or step S522, the process proceeds to step S530.

  According to the control of the flowchart of FIG. 3 described above, in the time zone (2), hot water storage that triggers activation of the heat pump device 200 when the amount of hot water stored in the hot water storage tank 100 decreases while the heat pump device 200 is stopped. The amount threshold value (hereinafter referred to as “heat pump activation hot water storage amount”) is changed according to the state of the heat pump drive flag Fhp. That is, when the heat pump drive flag Fhp is ON, the heat pump activation hot water storage amount is set to B. When the heat pump drive flag Fhp is OFF, the heat pump activation hot water storage amount is set to C.

  Next, with reference to FIG. 4, the start determination process of the combustion heating apparatus 300 in step S530 will be described. FIG. 4 is a flowchart showing a control operation (start-up determination process of combustion heating apparatus 300) performed by control device 500 in the first embodiment. When start determination processing of the combustion heating apparatus 300 is started in step S530, first, it is determined in step S531 whether or not the detected flow rate of the hot water supply flow rate sensor 601 is greater than zero. If the detected flow rate of the hot water supply flow rate sensor 601 is greater than 0, the process proceeds to step S532. When the detected flow rate of the hot water supply flow rate sensor 601 is 0, the process proceeds to step S533 to stop the combustion of the combustion heating apparatus 300, and the process proceeds to step S536 to end the start determination process of the combustion heating apparatus 300. .

  In step S532, it is determined whether or not the current hot water storage amount is D or more. When the current hot water storage amount is D or more, the process proceeds to step S534 to stop the combustion of the combustion heating apparatus 300, and the process proceeds to step S536 to end the activation determination process of the combustion heating apparatus 300. If the current hot water storage amount is less than D, the process proceeds to step S535 to start combustion of the combustion heating apparatus 300, and the process proceeds to step S536 to end the activation determination process of the combustion heating apparatus 300. When the current hot water storage amount of the hot water storage tank 100 is less than D and hot water is supplied to the hot water supply terminal 600 by the control of FIG. 4 described above, hot water supplied by the combustion heating device 300 is supplied to the hot water supply terminal 600. The hot water supply system 1 according to the first embodiment includes the combustion heating device 300 having a higher heating capacity than the heat pump device 200, so that hot water can be supplied to the hot water supply terminal 600 even when the amount of hot water stored in the hot water storage tank 100 is insufficient. It becomes possible.

  Next, the power supply state determination process in step S540 will be described with reference to FIG. FIG. 5 is a flowchart showing a control operation (power supply state determination process) performed by control device 500 in the first embodiment. When the power supply state determination process is started in step S540, first, in step S541, the heat pump predicted power Ee stored in advance in the storage unit of the control device 500 is read based on the heat pump incoming water temperature Tw and the outside air temperature DB. . In the first embodiment, the detected temperature of the lowest temperature sensor 104 is used as the heat pump incoming water temperature Tw, and the detected temperature of the outside air temperature sensor 201 is used as the outside air temperature DB. The heat pump predicted power Ee corresponds to the power required by the heat pump device 200 when performing HP boiling. The required power of the heat pump apparatus 200 changes according to the heat pump incoming water temperature Tw and the outside air temperature DB. In the first embodiment, the required power of the heat pump device 200 can be predicted with high accuracy by storing the relationship between the heat pump incoming water temperature Tw and the outside air temperature DB and the heat pump predicted power Ee in the storage unit of the control device 500 in advance. .

FIG. 6 is a schematic diagram of a look-up table in which the heat pump predicted power Ee is described based on the heat pump incoming water temperature Tw and the outside air temperature DB. In the look-up table shown in FIG. 6, the columns are divided by the outside air temperature DB, the rows are divided by the heat pump incoming water temperature Tw, the ridges are divided in increments of 10 ° C. from 10 ° C. to 60 ° C., and the value of the predicted heat pump power Ee for each ridge It is arranged as _{E 56} from _{E 11.} For example, the above processing can be realized by storing such a lookup table in a nonvolatile memory included in the storage unit of the control device 500.

  Subsequent to the process of step S541 described above, in step S542, the heat pump predicted power Ee is compared with the current generated power Ep of the solar power generation device 401. If Ep is greater than or equal to Ee, the process proceeds to step S543, and if Ep is less than Ee, the process proceeds to step S544. In the first embodiment, the current generated power Ep of the solar power generation device 401 corresponds to the power that can be supplied from the solar power generation device 401 to the heat pump device 200. In this invention, you may make it the structure which supplies the electric power generated of the solar power generation device 401 also to other electric equipments other than the heat pump apparatus 200. FIG. In that case, a value obtained by subtracting the power supplied to other electrical equipment from the current generated power Ep of the solar power generation device 401 is set as the power that can be supplied from the solar power generation device 401 to the heat pump device 200, and step S542 is performed. Then, the electric power and the heat pump predicted electric power Ee are compared.

  In step S543, the heat pump drive flag Fhp is turned on, the power supply flag Fpv is turned on, and the discharge flag Fd is turned off. The heat pump drive flag Fhp is a flag for switching the heat pump activation hot water storage amount as described above. The power supply flag Fpv is a flag indicating whether or not power supply from the solar power generation device 401 to the heat pump device 200 is permitted. The discharge flag Fd is a flag indicating whether or not power supply from the power storage device 402 to the heat pump device 200 is permitted. When power supply from the solar power generation device 401 to the heat pump device 200 is permitted, that is, when the solar power generation device 401 is included in the heat pump power source candidates, the power supply flag Fpv is turned ON. When power supply from the solar power generation device 401 to the heat pump device 200 is not permitted, that is, when the solar power generation device 401 is not included in the heat pump power source candidates, the power supply flag Fpv is turned off. When power supply from power storage device 402 to heat pump device 200 is permitted, that is, when power storage device 402 is included in a heat pump power source candidate, discharge flag Fd is turned ON. When power supply from power storage device 402 to heat pump device 200 is not allowed, that is, when power storage device 402 is not included in the heat pump power source candidates, discharge flag Fd is turned off. After step S543, the process proceeds to step S550, and the power state determination process ends.

  When the power (generated power Ep) that can be supplied from the solar power generation device 401 to the heat pump device 200 is equal to or higher than the necessary power (heat pump predicted power Ee) of the heat pump device 200, the power cost to the commercial power supply 403 is not applied. Since HP boiling can be performed, it is advantageous to perform HP boiling using the power generated by the photovoltaic power generation apparatus 401 in order to reduce the operating cost of the entire system. Therefore, in this Embodiment 1, the solar power generation device 401 is included in the heat pump power supply candidate by turning on the power supply flag Fpv in step S543.

  In step S544, a value obtained by subtracting the generated power Ep of the photovoltaic power generation apparatus 401 from the heat pump predicted power Ee and the daytime power purchase unit price Cb1 and a value obtained by multiplying the heat pump predicted power Ee by the night power purchase unit price Cb2 are obtained. Compare. If the former value is less than or equal to the latter value, the process proceeds to step S545. If the former value exceeds the latter value, the process proceeds to step S546. The daytime power purchase unit price Cb1 corresponds to the power unit price of the commercial power source 403 in the time zone (2). The night power purchase unit price Cb2 corresponds to the power unit price of the commercial power source 403 in the time zone (1).

  In step S545, the heat pump drive flag Fhp is turned on, the power supply flag Fpv is turned on, and the discharge flag Fd is turned off. That is, in step S545, the solar power generation device 401 is included in the heat pump power supply candidate, and the power storage device 402 is not included in the heat pump power supply candidate. After step S545, the process proceeds to step S550, and the power state determination process ends. In this Embodiment 1, when the electric power (generated electric power Ep) which can be supplied from the solar power generation apparatus 401 to the heat pump apparatus 200 is insufficient with respect to the required electric power (heat pump predicted electric power Ee) of the heat pump apparatus 200, the shortage In step S544, the power cost for supplementing the power with the power supplied from the commercial power source 403 and the power cost for driving the heat pump device 200 with the commercial power source 403 at night time are compared with each other. It can be determined whether or not to include the candidate. When the former power cost is less than or equal to the latter power cost, it is advantageous to suppress the operation cost of the entire system by performing HP boiling using the generated power of the solar power generation device 401. . Therefore, in this Embodiment 1, the solar power generation device 401 is included in the heat pump power supply candidate by turning on the power supply flag Fpv in step S545.

  In step S546, the value obtained by subtracting the generated power Ep of the photovoltaic power generation device 401 and the discharge power Ed of the power storage device 402 from the predicted heat pump power Ee and the daytime power purchase unit price Cb1 and the heat pump predicted power Ee are purchased at night. A value obtained by multiplying the unit price Cb2 is compared. If the former value is less than or equal to the latter value, the process proceeds to step S547. If the former value exceeds the latter value, the process proceeds to step S549. Discharge power Ed of power storage device 402 corresponds to power that can be supplied from power storage device 402 to heat pump device 200. In the first embodiment, control device 500 can detect the value of discharge power Ed of power storage device 402 via power supply regulator 400.

  In step S547, if the storage rate Rc of the power storage device 402 is greater than the first storage rate threshold value Rc1, the process proceeds to step S548, and if the storage rate Rc is equal to or less than the first storage rate threshold value Rc1, the process proceeds to step S549. The power storage rate Rc is an index of the amount of power stored in the power storage device 402. The first power storage rate threshold value Rc1 is a threshold value for determining whether power can be supplied from the power storage device 402 to the heat pump device 200. When the power storage rate Rc is greater than the first power storage rate threshold value Rc1, power can be supplied from the power storage device 402 to the heat pump device 200.

  In step S548, the heat pump drive flag Fhp is turned on, the power supply flag Fpv is turned on, and the discharge flag Fd is turned on. That is, in step S548, the solar power generation device 401 and the power storage device 402 are included in the heat pump power source candidates. After step S548, the process proceeds to step S550, and the power state determination process ends. In this Embodiment 1, when the electric power (generated electric power Ep) which can be supplied from the solar power generation apparatus 401 to the heat pump apparatus 200 is insufficient with respect to the required electric power (heat pump predicted electric power Ee) of the heat pump apparatus 200, the shortage In step S546, the power cost for supplementing the power with the power supplied from the commercial power source 403 and the power supplied from the power storage device 402 is compared with the power cost for driving the heat pump device 200 with the commercial power source 403 during the night time. Thus, it can be determined whether the solar power generation device 401 and the power storage device 402 are included in the heat pump power source candidates. When the former power cost is less than or equal to the latter power cost, performing HP boiling using the power supplied from the solar power generation device 401 and the power storage device 402 reduces the operating cost of the entire system. This is advantageous. Therefore, in the first embodiment, the power generation flag Fpv and the discharge flag Fd are turned on in step S548 so that the solar power generation device 401 and the power storage device 402 are included in the heat pump power source candidates.

  In step S549, the heat pump drive flag Fhp is turned off, the power supply flag Fpv is turned off, and the discharge flag Fd is turned off. That is, in step S548, the solar power generation device 401 and the power storage device 402 are not included in the heat pump power source candidates. After step S549, the process proceeds to step S550, and the power state determination process ends. When the power (generated power Ep) that can be supplied from the solar power generation device 401 to the heat pump device 200 is insufficient with respect to the necessary power (heat pump predicted power Ee) of the heat pump device 200, the shortage is supplied from the commercial power source 403. When the power cost supplemented with the power to be supplied and the power supplied from the power storage device 402 is higher than the power cost for driving the heat pump device 200 with the commercial power source 403 during the night time, the solar power generation device 401 and the power storage device 402 Not performing the HP boiling using the supplied power is advantageous in reducing the operating cost of the entire system. For this reason, in the first embodiment, the power generation flag Fpv and the discharge flag Fd are turned off in step S549 so that the solar power generation device 401 and the power storage device 402 are not included in the heat pump power source candidates. In addition, when the storage rate Rc is equal to or less than the first storage rate threshold value Rc1 in step S547, that is, when power cannot be supplied from the storage device 402 to the heat pump device 200, the process proceeds to step S549, where the power supply flag Fpv and the discharge are discharged. By setting the flag Fd to OFF, the solar power generation device 401 and the power storage device 402 are not included in the heat pump power source candidates.

  As described above, according to the process of the flowchart of FIG. 5, when the power supply flag Fpv is ON, the heat pump drive flag Fhp is turned ON, and when the power supply flag Fpv is OFF, the heat pump drive flag Fhp is OFF. Is done. Therefore, when the solar power generation device 401 is included in the heat pump power supply candidate, the heat pump activation hot water storage amount is B, and when the solar power generation device 401 is not included in the heat pump power supply candidate, the heat pump activation hot water storage amount is smaller than B. C. Thus, the value of the heat pump activation hot water storage amount is changed according to the configuration of the heat pump power source candidate. That is, when the solar power generation device 401 is included in the heat pump power supply candidate, the heat pump activation hot water storage amount is set to a larger value (B) than when the solar power generation device 401 is not included in the heat pump power supply candidate. .

  FIG. 7 is a flowchart showing a control operation (power supply switching process) performed by the control device 500 via the power supply regulator 400 in the first embodiment. When the power supply switching process is started in step S430, first, in step S431, it is determined whether HP boiling is being performed. If HP boiling is being performed, the process proceeds to step S432. If HP boiling is not being performed, the process proceeds to step S436. In step S432, it is determined whether the power supply flag Fpv is ON or OFF. If the power supply flag Fpv is ON, the process proceeds to step S433, and if the power supply flag Fpv is OFF, the process proceeds to step S436.

  In step S433, the power conditioner 400 is controlled to supply power from the solar power generation device 401 to the heat pump device 200, and the process proceeds to step S434. In step S434, it is determined whether the discharge flag Fd is ON or OFF. If the discharge flag Fd is ON, the process proceeds to step S435, and if the discharge flag Fd is OFF, the process proceeds to step S437. In step S435, power supply regulator 400 is controlled to supply power from power storage device 402 to heat pump device 200. In step S437, power supply regulator 400 is controlled to stop power supply from power storage device 402 to heat pump device 200. After step S435 or step S437, the process proceeds to step S431.

  In step S436, the power supply regulator 400 is controlled so as to stop power supply from the power storage device 402 to the heat pump device 200, and the process proceeds to step S438. In step S438, the storage rate Rc of the power storage device 402 is compared with the first storage rate threshold value Rc1, and if the storage rate Rc is equal to or less than the first storage rate threshold value Rc1, the process proceeds to step S439, where the storage rate Rc is If it exceeds the power storage rate threshold value Rc1, the process proceeds to step S440. In step S439, the power conditioner 400 is controlled so that power is supplied from the solar power generation device 401 to the power storage device 402 and stored in the power storage device 402, and the process proceeds to step S431.

  In step S440, the storage rate Rc of the power storage device 402 is compared with the second storage rate threshold value Rc2, and if the storage rate Rc is equal to or less than the second storage rate threshold value Rc2, the process proceeds to step S441, where the storage rate Rc is the second storage rate Rc. If it exceeds the power storage rate threshold value Rc2, the process proceeds to step S442. The second power storage rate threshold value Rc2 is a value larger than the first power storage rate threshold value Rc1. Second power storage rate threshold value Rc2 corresponds to power storage rate Rc when power storage device 402 is fully charged. In step S441, the power supply regulator 400 is controlled so that power is supplied from the solar power generation device 401 to the power storage device 402 and stored in the power storage device 402, and the process proceeds to step S431. In step S442, the power conditioner 400 is controlled so as to implement a reverse power flow in which the electric power generated by the photovoltaic power generation apparatus 401 flows to the power system of the commercial power supply 403, and the process proceeds to step S431.

  FIG. 8 is a graph showing changes in the amount of hot water stored and the cumulative hot water supply load in the daytime period when the hot water supply system of the comparative example is used. FIG. 9 is a graph showing changes in the amount of stored hot water and the accumulated hot water supply load in the daytime time zone (time zone (2)) when the hot water supply system 1 of the first embodiment is used. The operation of the hot water supply system of the comparative example shown in FIG. 8 is an operation when the heat pump device 200 driven by the commercial power source 403 and the combustion heating device 300 are combined, and the operation of the hot water supply system disclosed in Patent Document 1 is described. Corresponds to the action. The accumulated hot water supply load in FIGS. 8 and 9 is a value obtained by integrating the amount of hot water used. 8 and 9 show the operation when the accumulated hot water supply load has the same transition.

  The hot water storage amount A is secured in the hot water storage tank 100 by HP boiling in the night time zone (time zone (1)). In the operation of the hot water supply system of the comparative example shown in FIG. 8, the heat pump device 200 is activated and HP boiling is started at a time t <b> 1 when the hot water storage amount is reduced to C in the daytime period. By starting the HP boiling, the rate of decrease in the amount of stored hot water decreases. That is, the rate of decrease in the amount of hot water after time t1 is lower than the rate of decrease in the amount of hot water before time t1. Thereafter, the use of the combustion heating apparatus 300 is started at a time t2 when the amount of stored hot water decreases to D.

  In the operation of the hot water supply system 1 according to the first embodiment shown in FIG. 9, the heat pump device 200 is activated and the HP boiling is started at the time t3 when the amount of stored hot water decreases to B in the daytime time zone. By starting the HP boiling, the rate of decrease in the amount of stored hot water decreases. That is, the decrease rate of the hot water storage amount after time t3 is lower than the decrease rate of the hot water storage amount before time t3. Thereafter, use of the combustion heating apparatus 300 is started at a time t4 when the amount of stored hot water decreases to D.

  The hot water supply system 1 according to the first embodiment starts using the combustion heating apparatus 300 by starting HP boiling at a time t3 earlier than the time t1 when the hot water supply system of the comparative example starts HP boiling. The time point t4 can be delayed compared to the time point t2 in the case of the hot water supply system of the comparative example. Thus, according to the hot water supply system 1 of the first embodiment, the usage time of the heat pump device 200 with a low operating cost increases, and the use of the combustion heating device 300 with a high operating cost can be suppressed. Therefore, the operating cost of the entire system can be reduced.

  FIG. 9 shows the operation when the solar power generation device 401 is included in the heat pump power source candidates in the daytime time zone (time zone (2)). In the hot water supply system 1 according to the first embodiment, when the solar power generation device 401 is not included in the heat pump power source candidates in the daytime time zone (time zone (2)), the operation is similar to the operation in FIG. At the time t1 when the amount of stored hot water decreases to C, the heat pump device 200 is activated and HP boiling is started. When the solar power generation device 401 is not included in the heat pump power source candidate in the daytime time zone (time zone (2)), the operating cost of the heat pump device 200 in the daytime time zone (time zone (2)) increases. In this case, the hot water stored in the hot water storage tank 100 is used as much as possible at a low operating cost in the night time zone (time zone (1)), and the heat pump device 200 in the daytime time zone (time zone (2)) is used. The operation cost of the entire system can be lowered by suppressing the use time. In view of the above matters, in the first embodiment, the operating cost of the entire system can be reduced by switching the heat pump activation hot water storage amount between B and C in accordance with the configuration of the heat pump power source candidates.

DESCRIPTION OF SYMBOLS 1 Hot water supply system, 100 Hot water storage tank, 101 Upper temperature sensor, 102 Middle temperature sensor, 103 Lower temperature sensor, 104 Bottom temperature sensor, 105 Water pump, 106 Water supply port, 107 Water supply pipe, 108, 109 Water channel, 110 Hot water supply pipe, DESCRIPTION OF SYMBOLS 111 Water supply pipe, 112 Hot water supply pipe, 200 Heat pump apparatus, 201 Outside air temperature sensor, 300 Combustion type heating apparatus, 400 Power supply regulator, 401 Solar power generation apparatus, 402 Power storage apparatus, 403 Commercial power supply, 404, 405, 406, 407 Power line , 500 control device, 501 hot water storage measuring unit, 502 boiling determination unit, 503 power supply switching instruction unit, 600 hot water supply terminal, 601 hot water flow rate sensor

Claims (6)

A hot water storage tank for storing hot water supply water,
Hot water storage amount detecting means for detecting the hot water storage amount of the hot water storage tank;
A heat pump device for heating the water in the hot water storage tank;
A combustion heating device for heating hot water supply water;
A power supply regulator that switches a power source that supplies power to the heat pump device to a commercial power source, a photovoltaic power generation device, and a combination including one or more power storage devices, or
Depending on the power that can be supplied from the solar power generation device to the heat pump device and the amount of power stored in the power storage device, the commercial power source, the solar power generation device, and a combination including one or more of the power storage devices Is selected as a candidate for a power source that supplies power to the heat pump device, and a threshold value of the hot water storage amount that triggers the heat pump device to be activated when the hot water storage amount decreases while the heat pump device is stopped Control means for changing according to the candidate configuration;
Hot water supply system with   2. The hot water supply system according to claim 1, wherein when the candidate includes the solar power generation device, the control unit increases the threshold value compared to a case where the candidate does not include the solar power generation device. .   The hot water supply system according to claim 1 or 2, wherein the control unit determines whether or not electric power can be supplied from the power storage device to the heat pump device by comparing the power storage amount with a threshold value.   The said control means includes the said solar power generation device in the said candidate, when the electric power which can be supplied from the said solar power generation device to the said heat pump device is sufficient with respect to the required power of the said heat pump device. 4. The hot water supply system according to any one of 3.   When the electric power that can be supplied from the photovoltaic power generation apparatus to the heat pump apparatus is insufficient with respect to the necessary electric power of the heat pump apparatus, the control means supplements the shortage with the electric power supplied from the commercial power supply. The determination of whether to include the photovoltaic power generation device as the candidate by comparing the cost and the power cost for driving the heat pump device with the commercial power supply during night time. The hot-water supply system as described in any one.   When the electric power that can be supplied from the photovoltaic power generation apparatus to the heat pump apparatus is insufficient with respect to the necessary electric power of the heat pump apparatus, the control means uses the electric power supplied from the commercial power source and the power storage. The solar power generation device and the power storage device are included in the candidates by comparing the power cost supplemented with the power supplied from the device and the power cost of driving the heat pump device with the commercial power supply during night time The hot water supply system according to any one of claims 1 to 5, wherein it is determined whether or not.

Images