Geothermal energy recovery heat pump system, design method for geothermal energy recovery heat pump system

Abstract

This technology enables highly efficient operation regardless of the operating conditions of the ground source heat pump, and reduces the installation costs of the system. [Solution] A geothermal heat recovery heat pump system 1 comprises a geothermal heat source 50 that performs heat extraction and release, and a plurality of GSHP10 units that perform heat load processing by circulating a heat transfer medium between them and the geothermal heat source 50. The system further comprises a thermal energy storage power generation system 30 that stores input power as heat and outputs the stored heat as output power, a return pipe 21 through which the heat transfer medium moves from the thermal energy storage power generation system 30 and the plurality of GSHP10 units to the geothermal heat source 50, a supply pipe 22 through which the heat transfer medium moves from the geothermal heat source 50 to the thermal energy storage power generation system 30 and the plurality of GSHP10 units, and a bypass pipe that joins the supply pipe 22 and through which the heat transfer medium moves from the thermal energy storage power generation system 30 and the plurality of GSHP10 units to the supply pipe 22. The temperature of the heat transfer medium at the point where the bypass pipe joins the supply pipe 22 is controlled to be equal to the temperature of the heat transfer medium entering the supply pipe 22 from the geothermal heat source 50.

Description

[[Technical Field]]

[0001] The present disclosure relates to a geothermal heat utilization heat recovery heat pump system, and to a method for designing a geothermal heat utilization heat recovery heat pump system. [[Background Art]]

[0002] For example, Patent Documents 1 and 2 describe a geothermal heat utilization heat recovery heat pump system that performs bypass control. Such bypass control mixes a warmed heat medium and a cooled heat medium, performs mutual waste heat recovery between cooling warm waste heat and heating cold waste heat, and performs direct heat recovery, thereby minimizing the heat load processing by the geothermal heat source and improving the efficiency of heat pump operation. [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Publication No. 2021-148335 [[Patent Document 2]] Japanese Unexamined Patent Publication No. 2019-168184 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] However, when cooling warm waste heat and heating warm waste heat are generated within the same heat pump system, direct heat recovery via a bypass pipe is possible, but when only one of cooling warm waste heat or heating warm waste heat is generated within the same heat pump system, there is a problem that it is difficult to perform direct heat recovery.

[0005] The present disclosure has been made in view of such problems, and an object of the present disclosure is to provide a technology that enables highly efficient operation regardless of the operating conditions of a geothermal heat pump and can reduce the installation cost of the system. [[Means for Solving the Problem]]

[0006] The geothermal energy utilization heat recovery heat pump system of the present disclosure comprises a geothermal heat source that performs heat extraction and discharge, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between them and the geothermal heat source, and further comprises a thermal energy storage power generation system that stores input power as heat and outputs the stored heat as output power, a return pipe through which the heat medium moves from the thermal energy storage power generation system and the plurality of geothermal heat pumps to the geothermal heat source, a supply pipe through which the heat medium moves from the geothermal heat source to the thermal energy storage power generation system and the plurality of geothermal heat pumps, and a bypass pipe that merges with the supply pipe and through which the heat medium moves from the thermal energy storage power generation system and the plurality of geothermal heat pumps to the supply pipe, wherein the temperature of the heat medium at the portion where the bypass pipe merges with the supply pipe is controlled to be equal to the temperature of the heat medium entering the supply pipe from the geothermal heat source. Furthermore, the design method for a geothermal heat recovery heat pump system of the present disclosure comprises: a first heat storage capacity determination step of determining the heat storage capacity of the heat storage unit to be obtained under predetermined conditions based on the output of the first converter and the output of the second converter, a first setting step of setting the output of the second converter, which is the pre-set output, as output A, and the heat storage capacity determined in the first heat storage capacity determination step as heat storage capacity A, a second setting step of setting output B, which is the output of the second converter that is smaller than output A, a second heat storage capacity determination step of determining the heat storage capacity to be obtained under predetermined conditions based on output B, and setting the determined heat storage capacity as heat storage capacity B, and a comparison step of comparing heat storage capacity A and heat storage capacity B, wherein, as a result of the comparison step, in the first case where heat storage capacity B is larger than heat storage capacity A, output A and heat storage capacity A are adopted, and in cases other than the first case, output B is set as the new output A, and the second heat storage capacity determination step and the comparison step are repeated. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a technology that enables highly efficient operation regardless of the operating conditions of the ground source heat pump and can reduce the installation cost of the system. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows the configuration of a geothermal heat recovery heat pump system according to one embodiment of the present disclosure. [Figure 2] This figure shows the configuration of a geothermal heat recovery heat pump system according to a modified example of the present disclosure. [Figure 3] This figure shows the configuration of a geothermal heat recovery heat pump system according to a modified example of the present disclosure. [Figure 4] This is a flowchart illustrating the design method for the geothermal energy recovery heat pump system of this embodiment. [Figure 5] This flowchart shows a part of the design method for the geothermal energy recovery heat pump system of this embodiment. [Modes for carrying out the invention]

[0009] The following describes a geothermal heat recovery heat pump system 1 according to one embodiment of the present invention, with reference to Figures 1 to 5. In this embodiment, the "geothermal heat pump" may be referred to as "GSHP," and the "geothermal heat exchanger" may be referred to as "GHEX."

[0010] Figure 1 shows the configuration of the geothermal energy recovery heat pump system (Heart recovery ground source heart pump & Carnot battery system / HR-GSHP / CNBT system 1) that uses a thermal energy storage power generation system in conjunction with this embodiment. The HR-GSHP / CNBT system 1 consists of multiple types of GSHP10 (heat source units) with different applications, and a control unit 70 that performs measurement at each point of the system and controls the operation of the constituent equipment.

[0011] [HR-GSHP / CNBT System 1 Configuration] As shown in Figure 1, the geothermal energy recovery heat pump system (HR-GSHP / CNBT system 1) supplies the target load (thermal load). The HR-GSHP / CNBT system 1 comprises a geothermal heat exchanger 51 (also called GHEX 51), multiple heat pumps (GSHP 10) that circulate a heat transfer medium between the GHEX 51 and the system, a thermal energy storage power generation system 30, a piping system 20 that connects the GHEX 51, the multiple GSHP 10 and the thermal energy storage power generation system 30, and a control unit 70 that controls the HR-GSHP / CNBT system 1. The control unit 70 can be configured, for example, with a programmable controller (PLC) that controls the operation of the constituent equipment, and software implemented on a computer that sends control parameters to the PLC. The control unit 70 is not limited to this, and can also be configured with information processing equipment such as a server or a personal computer. The HR-GSHP / CNBT system 1 supplies heat or cold to the load.

[0012] GSHP10 adjusts the temperature of the heat transfer medium by circulating it through the piping system 20 to GHEX51. In this disclosure, a thermal energy storage power generation system 30 is connected to the piping system 20. The type of heat transfer medium is not limited. The heat transfer medium may be, for example, water.

[0013] The thermal energy storage power generation system 30, also known as a Carnot cell system, stores input power as heat and outputs the stored heat as output power. The thermal energy storage power generation system 30 of this embodiment includes a first converter 31, a heat storage unit 33, a second converter 32, and piping 35.

[0014] In this embodiment, the thermal energy storage power generation system 30 converts input power into heat using a first converter 31. The heat converted by the first converter 31 warms a heat transfer medium, which is then supplied to a thermal energy storage unit 33 via piping 35 and stored as heat in the thermal energy storage unit 33. The heat stored in the thermal energy storage unit 33 is supplied to a second converter 32 via piping 35 as a warmed heat transfer medium. The heat supplied as a warmed heat transfer medium is converted into electricity by the second converter 32 and becomes output power. Hereafter, a case in which a thermal energy storage geothermal heat pump (thermal energy storage GSHP) is used as the first converter 31 and a binary power generator is used as the second converter 32 will be described, but the first converter 31 and the second converter 32 are not limited to these. In this embodiment, electricity generated by a solar power generation panel 100 is used as input power, but the input power is not limited to this. As input power, from the viewpoint of reducing environmental impact, it is preferable to use electricity generated using renewable energy, for example. As renewable energy, wind power may be used, for example. Hereafter, the piping 35 that moves the heat transfer medium from the first converter 31 to the heat storage unit 33 may be referred to as the first piping 35a, and the piping 35 that moves the heat transfer medium from the heat storage unit 33 to the first converter 31 may be referred to as the second piping 35b. Furthermore, the piping 35 of the thermal energy storage power generation system 30 is not connected to the piping system 20. Therefore, the heat transfer medium moving within the piping 35 of the thermal energy storage power generation system 30 and the heat transfer medium moving within the piping system 20 are not mixed.

[0015] The piping system 20 includes a supply pipe 22 (first supply pipe 22a, second supply pipe 22b), a return pipe 21, and a bypass pipe 23. The first supply pipe 22a represents the supply pipe 22 before it merges with the bypass pipe 23, and the second supply pipe 22b represents the supply pipe 22 after it merges with the bypass pipe 23. The piping system 20 may be equipped with a pump P, a flow sensor M, and a temperature sensor T. The measurement results from the flow sensor M and the temperature sensor T may be sent to the control unit 70. The operation of the pump may be controlled by the control unit 70.

[0016] The first outgoing pipe 22a is a pipe to which the heat medium that has passed through GHEX 51 is supplied. The second outgoing pipe 22b is a pipe to which the heat medium that has passed through the first outgoing pipe 22a and the heat medium that has passed through the bypass pipe 23 are supplied, and is a pipe that moves the heat medium to GSHP 10 and the heat storage power generation system 30 (the first converter 31 and the second converter 32). A temperature sensor T may be provided in the outgoing pipe 22. In the present embodiment, a temperature sensor Tg is provided on the first outgoing pipe 22a, and a temperature sensor Ts is provided on the second outgoing pipe 22b. The temperature sensor T measures the temperature of the heat medium.

[0017] The return pipe 21 is a pipe that moves the heat medium that has passed through GSHP 10 or the heat storage power generation system 30 to GHEX 51.

[0018] The bypass pipe 23 is a pipe to which the heat medium after passing through the second regulating valve 11b is supplied, and moves the heat medium to the confluence point, which is the portion where the outgoing pipe 22 and the bypass pipe 23 merge, without passing through GHEX 51. The bypass pipe 23 merges the warmed heat medium and the cooled heat medium and supplies them to the outgoing pipe 22. The bypass pipe 23 is a pipe that mixes heat media of different temperatures and directly recovers heat. In other words, the bypass pipe 23 is a pipe that performs mutual waste heat recovery between cooling waste heat and heating cold waste heat, and performs direct heat recovery. A temperature sensor Tb may be provided in the bypass pipe 23.

[0019] Note that the warmed heat medium is, for example, a heat medium whose temperature becomes higher after passing through GSHP 10 or the second converter 32 than before passing through, due to the cold operation of GSHP 10 or the second converter 32. Further, the cooled heat medium is, for example, a heat medium whose temperature becomes lower after passing through GSHP 10 or the first converter 31 than before passing through, due to the hot operation of GSHP 10 or the first converter 31.

[0020] Note that the first converter 31 of the heat storage power generation system 30 is connected to the return pipe 21 and the bypass pipe 23 of the piping system 20. The second converter 32 is connected to the return pipe 21 and the bypass pipe 23 of the piping system 20. The temperature of the heat transfer medium can be obtained by a temperature sensor T. The temperature of the heat transfer medium obtained by the temperature sensor T is sent to, for example, the control unit 70.

[0021] The HR-GSHP / CNBT system 1 of this embodiment is equipped with three GSHPs (cooling / heating switching GSHPs) that can switch between cooling operation and heating operation. However, the number of GSHPs 10 installed in the heat pump system 1 and their combinations are not limited to this. It may also be equipped with a GSHP dedicated to cooling operation (cooling-only GSHP) or a GSHP dedicated to heating operation (heating-only GSHP).

[0022] A first control valve 11a is located between the GSHP10 and the return pipe 21. A second control valve 11b is located between the GSHP10 and the bypass pipe 23. A first switching valve 34a is located between the thermal energy storage power generation system 30 and the return pipe 21. A second switching valve 34b is located between the thermal energy storage power generation system 30 and the bypass pipe 23. Specifically, a first switching valve 34a is located between the first converter 31 and the return pipe 21, and between the second converter 32 and the return pipe 21, while a second switching valve 34b is located between the first converter 31 and the bypass pipe 23, and between the second converter 32 and the bypass pipe 23. A control valve is a valve that regulates the flow rate of fluid. A switching valve is a valve that can only be opened and closed. The control of the adjustment valve 11 and the switching valve 34 may be performed, for example, by the control unit 70.

[0023] In this embodiment, the GSHP10 is connected to the return pipe 21 and the bypass pipe 23 via the connecting pipe 12. The heat transfer medium that has passed through the GSHP10 is supplied to the connecting pipe 12. A first control valve 11a, located between the GSHP10 and the return pipe 21, and a second control valve 11b, located between the GSHP10 and the bypass pipe 23, adjust the amount of heat transfer fluid that has passed through the GSHP10 flowing into the return pipe 21 and the bypass pipe 23. The control valves 11 may also be proportional control valves.

[0024] In this embodiment, the first converter 31 is connected to the return pipe 21 and the bypass pipe 23 via the connecting pipe 12. The cooling heat transfer medium that has passed through the first converter 31 is supplied to the connecting pipe 12. A first switching valve 34a, located between the first converter 31 and the return pipe 21, and a second switching valve 34b, located between the first converter 31 and the bypass pipe 23, switch whether the heat transfer medium that has passed through the first converter 31 flows into the return pipe 21 or into the bypass pipe 23.

[0025] In this embodiment, the second converter 32 is connected to the return pipe 21 and the bypass pipe 23 via the connecting pipe 12. The heated heat transfer medium that has passed through the second converter 32 is supplied to the connecting pipe 12. A first switching valve 34a, located between the second converter 32 and the return pipe 21, and a second switching valve 34b, located between the second converter 32 and the bypass pipe 23, switch whether the heat transfer medium that has passed through the second converter 32 flows into the return pipe 21 or into the bypass pipe 23.

[0026] The connecting pipe 12 to which the heat transfer medium that has passed through the GSHP10 is supplied, and the connecting pipe 12 to which the heat transfer medium that has passed through the converters (first converter 31, second converter 32) is supplied, are equipped with a temperature sensor T for measuring the temperature of the heat transfer medium and a flow sensor M for measuring the flow rate of the heat transfer medium. Specifically, temperature sensors T are provided on the inlet and outlet sides of each GSHP10 and on the inlet and outlet sides of the converters (first converter 31, second converter 32), respectively, and flow sensors M are provided on the outlet side of each GSHP10 and on the outlet side of the converters (first converter 31, second converter 32).

[0027] With the above configuration, the temperature and flow rate of the heat medium that has passed through each GSHP10, the temperature and flow rate of the heat medium that has passed through the first converter 31, and the temperature and flow rate of the heat medium that has passed through the second converter 32 can be measured. The measured data on the temperature and flow rate of the heat medium may be collected in, for example, the control unit 70. Based on the measured data on the temperature and flow rate of the heat medium, the heat extraction and discharge amounts of each GSHP10, the first converter 31, and the second converter 32 are calculated. The heat extraction and discharge amounts of each GSHP10, the first converter 31, and the second converter 32 may be calculated in, for example, the control unit 70. By controlling the adjustment valve 11 and the switching valve 34 according to the calculated heat extraction and discharge amounts, the amount of heat transfer fluid that has passed through each GSHP 10, the first converter 31, and the second converter 32 flowing into the return pipe 21 and the bypass pipe 23 can be controlled.

[0028] As will be explained in more detail later, by controlling the adjustment valve 11 and the switching valve 34 according to the calculated heat extraction and release amounts, the temperature of the heat transfer medium at the point where the bypass pipe 23 merges with the supply pipe 22 is controlled to be equal to the temperature of the heat transfer medium entering the first supply pipe 22a from the geothermal heat source 50.

[0029] The HR-GSHP / CNBT system 1 of this embodiment further includes an auxiliary heat source to assist in heat extraction and dissipation by the geothermal heat source 50. The auxiliary heat source compensates for any insufficient heat supply from the geothermal heat exchanger 51 as a heat source. In this embodiment, a cooling auxiliary heat source 24 is provided as the auxiliary heat source. Note that the HR-GSHP / CNBT system 1 does not need to have an auxiliary heat source, or it may have a heating auxiliary heat source. In this embodiment, the cooling auxiliary heat source 24 is located on the inlet side of the GHEX 51. In this embodiment, the cooling auxiliary heat source 24 is a cooling tower, but the cooling auxiliary heat source 24 is not limited to a cooling tower.

[0030] [Operating Instructions for HR-GSHP / CNBT System 1] The HR-GSHP / CNBT system 1 is equipped with a bypass pipe 23. By controlling the circulation flow to the bypass pipe 23 according to the control flow shown below, heat transfer fluids with different temperatures are mixed, and some or all of the heat transfer fluid with the larger heat output is recovered directly before being sent to the GHEX 51.

[0031] This document describes the operation method and bypass control flow of the HR-GSHP / CNBT system 1. The operation method of the HR-GSHP / CNBT system 1 of this embodiment comprises a calculation step, a determination step, and a control step.

[0032] As described above, the connecting pipe 12 to which the heat transfer medium that has passed through the GSHP 10 is supplied, and the connecting pipe 12 to which the heat transfer medium that has passed through the converters (first converter 31, second converter 32) is supplied, are equipped with a temperature sensor T for measuring the temperature of the heat transfer medium and a flow sensor M for measuring the flow rate of the heat transfer medium. Therefore, the temperature and flow rate data of the heat transfer medium that has passed through each GSHP 10, the temperature and flow rate data of the heat transfer medium that has passed through the first converter 31, and the temperature and flow rate data of the heat transfer medium that has passed through the second converter 32 are aggregated, for example, in the control unit 70.

[0033] In the calculation process, based on the temperature and flow rate data aggregated in the control unit 70, the amount of heat extracted and released (individual heat extraction and release) for each GSHP10 and converter (first converter 31, second converter 32) is calculated. Based on the calculated heat extraction and release amounts for each GSHP10 and converter (first converter 31, second converter 32), the total heat extracted (total heat extracted) and heat released (total heat released) for the entire HR-GSHP / CNBT system 1 are then calculated.

[0034] Specifically, the amount of heat extracted and released for each GSHP10 and converter (first converter 31, second converter 32) (individual heat extraction and release amounts) is calculated as follows. Individual heat extraction / discharge amount = (temperature of the heat medium inside the supply pipe 22 - temperature of the heat medium that has passed through the GSHP10 or converter) × flow rate of the heat medium that has passed through the GSHP10 or converter ... Equation (A) Based on the individual heat extraction and release amounts calculated as described above, the total heat extraction amount (total heat extraction amount) and total heat release amount (total heat release amount) for the entire HR-GSHP / CNBT system 1 are calculated as follows. The total amount of heat extracted is calculated by adding the amount of heat extracted by the GSHP10, which is in the heat supply / heat extraction operation state, and the amount of heat extracted by the second converter 32. The total heat extraction amount is calculated by adding the heat dissipation amount of the GSHP10, which is in the cooling / heat dissipation operation state, and the heat dissipation amount of the first converter 31.

[0035] In the determination step, the amount of heat extracted and the amount of heat released are compared based on the calculation results of the total heat extracted and the amount of heat released for the entire HR-GSHP / CNBT system 1. In the determination step, it is determined which of the heat extracted or the heat released is dominant (higher in absolute value) for the entire HR-GSHP / CNBT system 1.

[0036] In the control process, the circulating flow rate to the bypass pipe 23 is controlled based on the determination result in the determination process. For example, the flow rate to the bypass pipe 23 of the heat transfer medium with the larger heat extraction / discharge capacity may be adjusted so that the temperature of the heat transfer medium at the point where the bypass pipe 23 merges with the supply pipe 22 (the junction) becomes equal to the temperature of the heat transfer medium entering the supply pipe 22 from the geothermal heat source 50.

[0037] Specifically, for example, if the HR-GSHP / CNBT system 1 as a whole is determined to have a large amount of heat extraction, the heat transfer medium that has passed through the GSHP 10, which is in the cooling / heat supply operation state, and the heat transfer medium that has passed through the second converter 32 are all supplied to the bypass pipe 23 by the control of the regulating valve 11 and the switching valve 34. At this time, among the regulating valve 11 that controls the flow rate of the heat transfer medium that has passed through the GSHP 10, which is in the cooling / heat supply operation state, the second regulating valve 11b, which adjusts the inflow of the heat transfer medium into the bypass pipe 23, is fully open, and the first regulating valve 11a, which adjusts the inflow of the heat transfer medium into the return pipe 21, is fully closed. Also, among the switching valve 34 that switches the supply destination of the heat transfer medium that has passed through the second converter 32, the second switching valve 34b, which adjusts the inflow of the heat transfer medium into the bypass pipe 23, is fully open, and the first switching valve 34a, which adjusts the inflow of the heat transfer medium into the return pipe 21, is fully closed. As a result, the entire amount of cooled heat transfer medium is supplied to the bypass pipe 23. Meanwhile, the flow rate of the heat transfer medium that has passed through the GSHP10, which is in the heat supply / heat extraction operation state, and the heat transfer medium that has passed through the first converter 31, to the bypass pipe 23 is adjusted by the control of the control valve 11 and the switching valve 34. At this time, among the switching valves 34 that switch the supply destination of the heat medium that has passed through the first converter 31, the second switching valve 34b, which adjusts the inflow of the heat medium into the bypass pipe 23, is fully closed, and the first switching valve 34a, which adjusts the inflow of the heat medium into the return pipe 21, is fully open. The heat medium that has passed through the GSHP10, which is in the heat supply / heat extraction operation state, is adjusted by the first adjustment valve 11a of the adjustment valves 11 so that a portion of the flow rate flows into the return pipe 21, and the remaining flow rate flows into the bypass pipe 23 so that it is mixed with the heat medium cooled in the bypass pipe 23, and the temperature of the heat medium at the point where the bypass pipe 23 merges with the first supply pipe 22a (the junction point) is controlled to be the same as the temperature of the heat medium entering the first supply pipe 22a from the geothermal heat source 50. Conversely, if, for example, the HR-GSHP / CNBT system 1 as a whole is determined to have a large amount of heat dissipation, the heat transfer medium that has passed through the GSHP 10 in the heat supply / heat extraction operation state, and the heat transfer medium that has passed through the first converter 31, are all supplied to the bypass pipe 23 by the control of the regulating valve 11 and the switching valve 34. At this time, among the regulating valve 11 that controls the flow rate of the heat transfer medium that has passed through the GSHP 10 in the heat supply / heat extraction operation state, the second regulating valve 11b, which adjusts the inflow of the heat transfer medium into the bypass pipe 23, is fully opened, and the first regulating valve 11a, which adjusts the inflow of the heat transfer medium into the return pipe 21, is fully closed. Also, among the switching valve 34 that switches the supply destination of the heat transfer medium that has passed through the first converter 31, the second switching valve 34b, which adjusts the inflow of the heat transfer medium into the bypass pipe 23, is fully opened, and the first switching valve 34a, which adjusts the inflow of the heat transfer medium into the return pipe 21, is fully closed. As a result, the entire amount of heated heat transfer medium is supplied to the bypass pipe 23. Meanwhile, the flow rate of the heat transfer medium that has passed through the GSHP10, which is in a cooling / heat dissipation operation state, and the heat transfer medium that has passed through the second converter 32, to the bypass pipe 23 is adjusted by the control of the control valve 11 and the switching valve 34. At this time, of the switching valves 34 that switch the destination of the heat transfer medium that has passed through the second converter 32, the second switching valve 34b, which adjusts the inflow of the heat transfer medium into the bypass pipe 23, is fully closed, and the first switching valve 34a, which adjusts the inflow of the heat transfer medium into the return pipe 21, is fully open. The heat transfer medium that has passed through the GSHP10, which is in the cooling / heat dissipation operation state, is adjusted by the first adjustment valve 11a of the adjustment valves 11, so that a portion of the flow rate flows into the return pipe 21, and the remaining flow rate flows into the bypass pipe 23, which is adjusted by the second adjustment valve 11b. The heat transfer medium is mixed with the heat transfer medium heated in the bypass pipe 23, and the temperature of the heat transfer medium at the point where the bypass pipe 23 merges with the first supply pipe 22a (the junction) is controlled so that it is equal to the temperature of the heat transfer medium entering the first supply pipe 22a from the geothermal heat source 50.

[0038] The basic configuration of the HR-GSHP / CNBT system 1 described herein is as above, but additional equipment may be added to the thermal energy storage system 30 as needed, as shown in the following modified examples. The HR-GSHP / CNBT system 1 generates cold heat (heat extraction) from the thermal storage HP and hot waste heat (heat discharge) from the binary power generator throughout the year. Additional equipment may be added, for example, if the basic configuration described above does not achieve the target cost reduction effect (reduction in the use of the ground source heat exchanger 51 or reduction in system power consumption).

[0039] (First variation) Figure 2 shows the configuration of the first modified HR-GSHP / CNBT system 1A. The thermal energy storage power generation system 30A of the first modified HR-GSHP / CNBT system 1A has a third converter 36 as additional equipment. The third converter 36 may be, for example, an air-cooled heat pump (air-cooled HP).

[0040] The third converter 36 is connected to the first pipe 35a, which connects the first converter 31 and the heat storage unit 33 via the first connecting pipe 37a, and to the second pipe 35b, which connects the first converter 31 and the heat storage unit 33 via the second connecting pipe 37b. Furthermore, the modified thermal energy storage power generation system 30A has a third switching valve 38a on the inlet side of the confluence point between the first pipe 35a and the first connecting pipe 37a in the first pipe 35a, and on the outlet side of the confluence point between the second pipe 35b and the second connecting pipe 37b in the second pipe 35b, and a fourth switching valve 38b in the first connecting pipe 37a and the second connecting pipe 37b, respectively.

[0041] In office buildings and commercial facilities, there is a lot of internal heat generation, and the amount of heat released for cooling in the summer is greater than the amount of heat collected for heating in the winter. Therefore, the volume of the ground heat exchanger 51 is determined by the amount of heat released in the summer, and even if the heat collected by the thermal storage HP overlaps with the heat collected for heating in the winter, the reduction effect of the ground heat exchanger 51 is not significantly impaired because there is relatively little surplus electricity in the winter. However, in buildings where the difference between the amount of heat released for cooling and the amount of heat collected for heating is not large, such as school facilities where there is not much internal heat generation, if the amount of heat collected by the thermal storage HP overlaps with the amount of heat collected for heating in the winter, it will exceed the amount of heat released for cooling in the summer, and the reduction effect of the ground heat exchanger 51 will be impaired. In the case of a building with such a heat load configuration, a third converter 36 (air-cooled HP) is installed, and during the heating season, the operation of the first converter (thermal storage HP) is limited to the amount of heat extracted that does not impair the reduction effect of the ground heat exchanger 51. Beyond that point, the supply of surplus electricity is switched from the first converter 31 to the air-cooled HP, and the air-cooled HP is used to store heat from surplus solar power generation.

[0042] Specifically, the thermal energy storage power generation system 30A of this modified example is controlled as follows. For example, during the cooling season, if the cold exhaust heat from the thermal energy storage system 30A to the piping system 20 can be effectively recovered by directly combining it with the warm exhaust heat from the cooling heat radiated by the GSHP 10, the surplus power is controlled to be supplied only to the first converter 31 (supply path B). At the same time, the third switching valve 38a is opened and the fourth switching valve 38b is closed to circulate the heat transfer medium between the first converter 31 and the heat storage unit 33. This allows the first converter 31 to convert electricity into heat, store the converted heat in the heat storage unit 33, and supply the cold exhaust heat generated in the process of converting electricity into heat to the piping system 20. On the other hand, if, for example, during the heating season, the cold exhaust heat from the thermal energy storage system 30A to the piping system 20 combines with the cold exhaust heat from the heating heat radiated by the GSHP 10, increasing the capacity of the ground heat exchanger 51 and becoming detrimental, the surplus power is controlled to be supplied only to the third converter 36 (supply path A). At the same time, the fourth switching valve 38b is opened and the third switching valve 38a is closed in order to circulate the heat transfer medium between the third converter 36 and the heat storage unit 33. This allows the surplus power to be used to release the cold exhaust heat generated from the third converter 36 (air-cooled HP) into the atmosphere. Therefore, the cold exhaust heat generated when converting electricity to heat is not released into the piping system 20, and the converted heat can be stored in the heat storage unit 33. The above control may be performed, for example, by the control unit 70.

[0043] (Second variation) Figure 3 shows the configuration of the second modified HR-GSHP / CNBT system 1B. The thermal energy storage power generation system 30B of the second modified HR-GSHP / CNBT system 1B is equipped with an additional cooling auxiliary heat source 60 as additional equipment. In this embodiment, the additional cooling auxiliary heat source 60 is a cooling tower, but is not limited thereto.

[0044] The additional cooling auxiliary heat source 60 is connected via a third connecting pipe 40a to the supply pipe 22 leading to the second converter 32, and via a fourth connecting pipe 40b to the connecting pipe 12 through which the heat transfer medium that has passed through the second converter 32 travels. Furthermore, the modified thermal energy storage power generation system 30B has a fifth switching valve 39a in both the third connecting pipe 40a and the fourth connecting pipe 40b. In addition, the supply pipe 22 leading to the second converter 32 has a sixth switching valve 39b on the inlet side of the junction of the supply pipe 22 leading to the second converter 32 and the third connecting pipe 40a, and the connecting pipe 12 has a sixth switching valve 39b on the outlet side of the junction of the connecting pipe 12 and the fourth connecting pipe 40b.

[0045] The second converter 32 (binary generator) generates hot waste heat (heat dissipation) during power generation. In the basic embodiment, similar to conventional GSHP systems, the heat fluid supplied to the return pipe 21 is processed by releasing the hot waste heat into the atmosphere at the cooling auxiliary heat source 24 installed in the return pipe 21 before it enters the ground heat exchanger 51. However, with this method, it is not possible to release 100% of the generated hot waste heat into the atmosphere, and some of it may be released into the ground. In particular, if the hot waste heat is concentrated during the cooling season (summer), it may impair the reduction effect of the ground heat exchanger 51. In such cases, by arranging an additional cooling auxiliary heat source 60 in the thermal energy storage power generation system 30 as described above, the heat fluid that has passed through the second converter 32 (binary generator) is moved to the additional cooling auxiliary heat source 60 during the cooling season, and the hot waste heat is released into the atmosphere.

[0046] Specifically, the thermal energy storage power generation system 30B of this modified example is controlled as follows. For example, during the heating season, if the hot waste heat from the thermal energy storage system 30B to the piping system 20 can be directly recovered with the cold waste heat from the GSHP 10's heating, the heat transfer medium that has passed through the second converter 32 is not supplied to the additional cooling auxiliary heat source 60, but is supplied to the return pipe 21 or bypass pipe 23. Therefore, if it is necessary to supply hot waste heat from the thermal energy storage system 30B to the piping system 20, the two sixth switching valves 39b are opened and the two fifth switching valves 39a are closed. This allows the hot waste heat generated from the second converter 32 to be supplied to the piping system 20. On the other hand, for example, during the cooling season, if the cooling load of the GSHP 10 is excessive and the hot waste heat from the thermal energy storage system 30B to the piping system 20 is added to the hot waste heat from cooling, the cooling auxiliary heat source 24 cannot dissipate the excess hot waste heat into the atmosphere, the heat transfer medium that has passed through the second converter 32 is controlled to be supplied only to the additional cooling auxiliary heat source 60. At this time, in order to circulate the heat source between the second converter 32 and the additional cooling auxiliary heat source 60, the two fifth switching valves 39a are opened and the two sixth switching valves 39b are closed. This allows the waste heat generated from the second converter 32 to be released into the atmosphere by the additional cooling auxiliary heat source 60. Therefore, power generation can be performed without releasing the waste heat generated when converting heat into electricity into the piping system 20. The above control may be performed, for example, by the control unit 70.

[0047] [Design Method for HR-GSHP / CNBT System 1] The output of the second converter 32 (binary generator) and the heat storage capacity of the accumulator 33 required for proper operation vary depending on the scale of the HR-GSHP / CNBT system 1. Therefore, when designing the HR-GSHP / CNBT system 1, it is preferable to appropriately determine the heat storage capacity of the second converter 32 (binary generator) and the accumulator 33.

[0048] Figure 4 shows a flowchart illustrating the design method of the HR-GSHP / CNBT system 1 according to this embodiment. As shown in Figure 4, the design method for the HR-GSHP / CNBT system 1 of this embodiment includes a first heat storage capacity determination step, a setting step, a second heat storage capacity determination step, and a comparison step.

[0049] <First heat storage capacity determination process> In the first heat storage capacity determination step, the heat storage capacity of the heat storage unit 33 of the heat storage power generation system 30 is determined under predetermined conditions based on the preset outputs of the first converter 31 and the second converter 32 (S100A). Details of the method for calculating the heat storage capacity based on the preset output of the second converter 32 will be described later.

[0050] <Setting process> The setting process of this embodiment includes a first setting step and a second setting step. In the first setting step, the output of the second converter 32, which has been set in advance, is set as output A, and the heat storage capacity determined in the first heat storage capacity determination step is set as heat storage capacity A (S200). In the second setting step, output B, which is the output of the second converter 32 that is smaller than output A, is set (S300).

[0051] <Second heat storage capacity determination process> In the second heat storage capacity determination step, the heat storage capacity required under predetermined conditions is determined based on the output B of the second converter 32 set in the second setting step, and the determined heat storage capacity is set as the heat storage capacity B (S100B).

[0052] <Comparison process> In the comparison process, heat storage capacity A and heat storage capacity B are compared (S400). If the comparison process results in a first case where the heat storage capacity B is greater than the heat storage capacity A, output A is adopted as the output of the second converter 32, and heat storage capacity A is adopted as the heat storage capacity of the heat storage unit 33 (S600). If the result of the comparison process is not the first case, output B is set as the new output A (S500), and the second setting process, the second heat storage capacity determination process, and the comparison process are repeated.

[0053] Figure 5 shows a detailed flow chart of the process for determining the heat storage capacity. In this embodiment, the heat storage capacity is calculated as follows based on the output of the second converter 32, which is set in advance.

[0054] The heat storage capacity determination step of this embodiment comprises a surplus power calculation step, a heat storage amount calculation step, and a maximum heat storage amount determination step.

[0055] <Process for calculating surplus electricity> In the surplus power calculation process, the amount of surplus power for each time period is calculated (S111). Specifically, for example, as in this embodiment, when the thermal energy storage power generation system 30 utilizes surplus power from the solar power generation panels 100, the annual hourly data of the amount of power generated by the solar power generation panels 100 (solar power generation amount) and the annual hourly data of the amount of electricity received by the target building (for example, the building on which the HR-GSHP / CNBT system 1 is installed) are estimated. Based on the estimated annual hourly data, the amount of surplus power for each time period is calculated. Hereafter, when the amount of surplus power is expressed as positive, it indicates that there is power supplied to the thermal energy storage power generation system 30, and when the amount of surplus power is expressed as negative or 0, it indicates that there is a power shortage, i.e., there is no power supplied to the thermal energy storage power generation system 30.

[0056] <Heat storage amount calculation process> In the heat storage amount calculation process, the amount of heat stored at each time is calculated based on the amount of surplus electricity at each time. This calculation of heat storage at each time is performed, for example, for all times of the year. Specifically, the amount of heat stored at each time point is calculated as follows.

[0057] First, it is determined whether the amount of surplus power calculated in the surplus power calculation process at time t is positive (S112).

[0058] (If the surplus power at time t is positive) Assuming that the first converter 31 (thermal storage HP) is in operation when the surplus power at time t is positive, the amount of heat stored at time t is calculated as follows (S113). The expected output (expected output) when the first converter 31 is operated by the surplus power at time t is compared with the maximum output of the first converter 31. The expected output (expected output) when the first converter 31 is operated by the surplus power at time t is calculated by the following equation (B). Expected output = surplus power at time t × COP of the first converter 31 ... Equation (B)

[0059] The expected output is compared with the maximum output of the first converter 31 (S114). If the expected output is greater than the maximum output of the first converter 31, the load of the first converter 31 at time t equals the maximum output of the first converter 31 (S115). On the other hand, if the expected output at time t is less than the maximum output of the first converter 31, the load of the first converter 31 at time t equals the expected output (S116).

[0060] Based on the load of the first transducer 31 at time t calculated as described above, the amount of heat stored at time t is calculated (S117). The amount of heat stored at time t is calculated using the following formula (C). Heat stored at time t = Heat stored at t-1 + Load of the first transducer 31 at time t ... Equation (C)

[0061] (If the surplus power at time t is negative or zero) If the surplus power at time t is negative or 0, it is determined whether the amount of stored heat at time t-1 is greater than 0 (S118). If the amount of stored heat at time t-1 is greater than 0, the second converter 32 (binary generator) is operated. Therefore, the amount of heat consumed when the second converter 32 is operating at time t is calculated. Based on the calculated amount of heat consumed due to the operation of the binary generator, the amount of stored heat at time t is calculated (S119). The amount of stored heat at time t is calculated using the following formula (D). Heat stored at time t = Heat stored at t-1 - Heat consumed by the second transducer 32 at time t ... Equation (D) Furthermore, if the amount of heat stored at time t-1 is 0 or less, the second converter 32 will not be operated (S120).

[0062] The above process is repeated until the calculation of the heat storage amount for each time of day throughout the year is completed (S121, S122). In this way, the heat storage amount calculation process calculates the heat storage amount for each time of day throughout the year. Note that the heat storage amount for each time of day calculated here is a predicted value.

[0063] <Maximum heat storage amount determination process> The amount of heat stored at each time of day throughout the year, calculated in the heat storage amount calculation process, is compared, and the amount of heat stored at the time with the maximum amount of heat stored is taken as the maximum amount of heat stored at each time. The maximum amount of heat stored determined in this way is determined as the heat storage capacity of the heat storage unit 33 (S123).

[0064] As described above, the geothermal energy utilization heat recovery heat pump system 1 of the present disclosure comprises a geothermal energy source 50 that performs heat extraction and discharge, and a plurality of GSHP 10 units that perform heat load processing by circulating a heat medium between them and the geothermal energy source 50. The system comprises a thermal energy storage power generation system 30 that stores input power as heat and outputs the stored heat as output power, a return pipe 21 through which the heat medium moves from the thermal energy storage power generation system 30 and the plurality of GSHP 10 to the geothermal energy source 50, a supply pipe 22 through which the heat medium moves from the geothermal energy source 50 to the thermal energy storage power generation system 30 and the plurality of GSHP 10, and a bypass pipe 23 that joins the supply pipe 22 and through which the heat medium moves from the thermal energy storage power generation system 30 and the plurality of GSHP 10 to the supply pipe 22. The temperature of the heat medium at the point where the bypass pipe 23 joins the supply pipe 22 is controlled to be equal to the temperature of the heat medium entering the supply pipe 22 from the geothermal energy source 50. For example, the amount of electricity generated by the solar power generation panel 100 depends on the amount of sunlight, and therefore does not necessarily match the power load demand at any given time, resulting in either a surplus of power or a power shortage. The thermal energy storage power generation system 30, for example, generates heat using a thermal energy storage heat pump (first converter 31) during periods of surplus power, stores the generated heat in a thermal energy storage unit 33, and when a power shortage occurs, uses the stored heat to operate a generator (second converter 32) and supply power. At this time, cold waste heat is generated when hot water is produced by the thermal energy storage heat pump, and warm waste heat is generated when the hot water is used to operate the power generation device and supply power. With the above configuration, even if only cooling waste heat or heating waste heat is generated in the GSHP10, the other waste heat resulting from the operation of the thermal energy storage power generation system 30 can be fed into the bypass pipe 23, enabling direct heat recovery in the bypass pipe 23. Specifically, for example, if only cooling waste heat is generated in the GSHP10, the cooling waste heat generated when producing hot water in the thermal energy storage heat pump of the thermal energy storage power generation system 30 can be supplied to the bypass pipe 23, enabling direct heat recovery. Therefore, a geothermal heat recovery heat pump system 1 can be made that enables highly efficient operation regardless of the operating conditions of the GSHP10 and reduces the installation cost of the system.

[0065] Furthermore, the thermal energy storage power generation system 30 may also include a first converter 31 that converts input power into heat, a thermal storage unit 33 that stores the heat converted by the first converter 31, and a second converter 32 that converts the heat stored in the thermal storage unit 33 into power to produce output power. The operation of the first converter 31, which converts input power into heat, generates cold waste heat, and the operation of the second converter 32, which converts the heat stored in the heat storage unit 33 into power to produce output power, generates warm waste heat. With the configuration described above, the geothermal heat recovery heat pump system 1 can utilize the cold waste heat generated by the operation of the first converter 31 and the hot waste heat generated by the operation of the second converter 32. Therefore, even if, for example, only one of either the cooling waste heat or the heating waste heat is generated by the operation of the GSHP 10, the other waste heat generated as a result of the operation of the thermal energy storage power generation system 30 can be flowed into the bypass pipe 23, and direct heat recovery can be performed in the bypass pipe 23. Therefore, a geothermal heat recovery heat pump system 1 can be made that enables highly efficient operation regardless of the operating conditions of the GSHP10 and reduces the installation cost of the system.

[0066] Furthermore, the thermal energy storage power generation system 30 may discharge the heat transfer medium cooled by the first converter 31 to at least one of the return pipe 21 and the bypass pipe 23, and discharge the heat transfer medium heated by the second converter 32 to at least one of the return pipe 21 and the bypass pipe 23. With this configuration, it is possible to control whether the cooled heat transfer medium and the heated heat transfer medium generated as a result of the operation of the thermal energy storage power generation system 30 are supplied to the return pipe 21 or the bypass pipe 23. For this reason, even if only one of either cooling waste heat or heating waste heat is generated by the operation of the GSHP 10, the other waste heat generated as a result of the operation of the thermal energy storage power generation system 30 can be fed into the bypass pipe 23, thereby enabling direct heat recovery in the bypass pipe 23. Therefore, a geothermal heat recovery heat pump system 1 can be made that enables highly efficient operation regardless of the operating conditions of the GSHP10 and reduces the installation cost of the system.

[0067] Furthermore, the input power may be generated from renewable energy sources. Renewable energy generation can experience significant fluctuations in power output depending on the season and weather. For example, the amount of electricity generated by a solar power panel 100 depends on the amount of sunlight and therefore does not necessarily match the power load demand at any given time, resulting in either a surplus or a shortage of power. With the above configuration, surplus electricity (surplus energy) generated by renewable energy generation can be stored, for example, as hot water by the thermal energy storage system 30, and when there is a power shortage, the stored hot water can be used to operate the power generation device and supply electricity. Therefore, a geothermal heat recovery heat pump system 1 can be made that enables highly efficient operation regardless of the operating conditions of the GSHP10, reduces system installation costs, effectively utilizes surplus electricity from renewable energy sources, and suppresses environmental impact.

[0068] Furthermore, an auxiliary heat source may be provided to supplement the geothermal heat source 50. As a result of operating multiple GSHP10 units, if, for example, either the amount of heat extracted or the amount of heat released becomes excessively large, the heat load processing by the geothermal heat source 50 may not be able to adequately handle the extracted and released heat. With the above configuration, for example, the amount of extracted and released heat that cannot be handled by the geothermal heat source 50 can be processed by an auxiliary heat source, thereby assisting the heat load processing by the geothermal heat source 50.

[0069] Furthermore, the thermal energy storage power generation system 30A may also include a third converter 36, the third converter 36 of which may be an air-cooled heat pump. The HR-GSHP / CNBT system 1 generates cold heat (heat extraction) from the thermal storage HP and hot waste heat (heat release) from the binary power generator throughout the year. For example, if the cold waste heat from the thermal storage HP coincides with the heating season, it will impair the reduction effect of the ground heat exchanger 51. In the case of a building with such a heat load configuration, a third converter 36 (air-cooled thermal storage HP) is installed, and during the heating season, the system switches from ground heat to the air-cooled HP to store heat using surplus solar power. With this configuration, if releasing the cold waste heat generated by the operation of the first converter 31 into the piping system 20 would be detrimental, the surplus power can be supplied to the air-cooled thermal storage HP (third converter 36), thereby reducing the inflow of cold waste heat into the piping system 20. Therefore, highly efficient operation is possible regardless of the operating status of the GSHP 10, and the installation cost of the system can be reduced.

[0070] Furthermore, the thermal energy storage power generation system 30B may also be equipped with a cooling auxiliary heat source 24. Similar to conventional heating and cooling switching GSHP10s, after all the heat transfer fluids that have passed through the GSHP10s merge, it is possible to process the waste heat using a cooling tower installed in the return pipe 21 before the heat transfer fluid enters the ground heat exchanger 51. However, even with this method, it is not possible to release all the waste heat into the atmosphere, and some may end up being released into the ground, which can impair the reduction effect of the ground heat exchanger 51. In such cases, for example, an additional cooling auxiliary heat source 60 dedicated to the thermal energy storage power generation system 30 can be installed, and during the cooling season, the destination of the heat release can be switched from the return pipe 21 to a cooling tower provided in the thermal energy storage power generation system 30B, making it possible to process 100% of the waste heat generated by the thermal energy storage power generation system 30B by releasing it into the atmosphere. Therefore, highly efficient operation is possible regardless of the operating conditions of the GSHP10s, and the installation cost of the system can be reduced.

[0071] Each of the multiple GSHP10 units may be equipped with a control valve 11 between the return pipe 21 and the bypass pipe 23, and the control valve 11 may be used to control the temperature of the heat transfer medium at the point where the bypass pipe 23 merges with the supply pipe 22 so that it is equal to the temperature of the heat transfer medium entering the supply pipe 22 from the ground heat exchanger 51. By controlling the control valve 11, the amount of heat transfer medium supplied from each GSHP 10 to the bypass pipe 23 can be adjusted, making the temperature of the heat transfer medium that has passed through the bypass pipe 23 approximately the same as the temperature of the heat transfer medium at the inlet of the junction. For example, a portion of the heat dissipation occurring on the return pipe 21 side and the same amount of heat as the heat extracted on the return pipe 21 side can be mutually recovered. Therefore, only the heat dissipation remaining after subtracting the same amount of heat extracted on the return pipe 21 side from the heat dissipation occurring on the return pipe 21 side is sent to the return pipe 21 and heat exchange is performed in the ground heat source 50, thus reducing the volume of the ground heat source 50, i.e., the number of ground heat exchangers 51 (GHEX 51). Thus, highly efficient operation is possible regardless of the operating conditions of the GSHP 10, and the installation cost of the system can be reduced. Furthermore, by limiting the reduction in volume of the geothermal heat source 50 to a certain extent, changes in the temperature of the ground, which is the heat source, can be mitigated, resulting in a geothermal heat recovery heat pump system 1 that can operate more efficiently regardless of the scale of the system.

[0072] Furthermore, the control valve 11 may be a proportional control valve. With this configuration, the flow rate of the heat transfer medium can be controlled by a proportional control valve, making it easy to set the temperature of the heat transfer medium moving through the bypass pipe 23 to be the same as the temperature of the heat transfer medium moving through the supply pipe 22. Therefore, highly efficient operation is possible regardless of the operating conditions of the GSHP10, and the installation cost of the system can be reduced.

[0073] The geothermal energy recovery heat pump system 1 of this disclosure may be designed as follows: The process includes: a first heat storage capacity determination step which determines the heat storage capacity of a heat storage accumulator 33 required under predetermined conditions based on the outputs of a first converter 31 and a second converter 32 set in advance; a first setting step which, after the first heat storage capacity determination step, sets the output of the second converter 32 set in advance as output A and the heat storage capacity determined in the first heat storage capacity determination step as heat storage capacity A; a second setting step which sets output B, which is the output of the second converter 32 that is smaller than output A; a second heat storage capacity determination step which determines the heat storage capacity required under predetermined conditions based on output B and sets the determined heat storage capacity as heat storage capacity B; and a comparison step which compares heat storage capacity A and heat storage capacity B. In the first case where, as a result of the comparison step, heat storage capacity B is larger than heat storage capacity A, output A and heat storage capacity A are adopted; in cases other than the first case, output B is set as the new output A, and the second heat storage capacity determination step and the comparison step are repeated.

[0074] Furthermore, at least one of the first heat storage capacity determination step and the second heat storage capacity determination step includes a surplus power calculation step that calculates the surplus power amount for each time period, a heat storage amount calculation step that calculates the heat storage amount for each time period based on the surplus power amount for each time period, and a maximum heat storage amount determination step that compares the heat storage amounts for each time period and determines the maximum value of the heat storage amount for each time period as the heat storage capacity. In the heat storage amount calculation step, if it is determined that the surplus power amount for each time period is negative or zero, the heat storage amount may be calculated based on the output of the second converter 32.

[0075] The output of the second converter 32 (binary generator) and the heat storage capacity of the accumulator 33 required for proper operation vary depending on the scale of the HR-GSHP / CNBT system 1. Therefore, when designing the HR-GSHP / CNBT system 1, it is preferable to appropriately determine the heat storage capacity of the second converter 32 (binary generator) and the accumulator 33. With the configuration described above, it is possible to determine the appropriate output of the second converter 32 and the heat storage capacity of the heat storage unit 33 based on the output of the set first converter 31. Therefore, this can be a design method for operating a geothermal heat recovery heat pump system 1 that enables highly efficient operation regardless of the operating conditions of the GSHP 10 and reduces the installation cost of the system.

[0076] Although one embodiment of this disclosure has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment and may include modifications, combinations, deletions, etc., of the configuration that do not depart from the gist of this disclosure.

[0077] For example, it is not necessary to have an auxiliary heat source, and it may have only one of either a heating auxiliary heat source or a cooling auxiliary heat source 24, or it may have both a heating auxiliary heat source and a cooling auxiliary heat source 24. The number and type of GSHP10 are not limited; for example, there may be one unit or multiple units. For example, the thermal energy storage power generation system 30 may include both a third converter 36, which is an additional piece of equipment for the first modified example, and an additional cooling auxiliary heat source 60, which is an additional piece of equipment for the second modified example. [Explanation of symbols]

[0078] 1, 1A, 1B Geothermal Energy Recovery Heat Pump System (HR-GSHP / CNBT System) 10. Ground Source Heat Pump (GSHP) 11. Adjustment valve 11a First regulating valve 11b Second Adjustment Valve 12 connecting pipes 20 Piping system 21 Return 22 Outbound 22a 1st outbound pipe 22b 2nd outbound pipe 23 Bypass pipe 24 Cooling auxiliary heat source 30, 30A, 30B Thermal Energy Storage System 31. First Converter 32 Second Converter 33 Heat storage 34. Switching valve 34a First switching valve 34b Second switching valve 35 Piping 35a 1st piping 35b 2nd piping 36 Third Converter 37a First connecting pipe 37b Second connecting pipe 38a Third switching valve 38b Fourth switching valve 39a Fifth switching valve 39b Sixth switching valve 40a Third connecting pipe 40b Fourth connecting pipe 50 Geothermal heat source 51 Geothermal heat exchanger 60 Additional cooling auxiliary heat source 70 Control Unit 100 solar panels T temperature sensor M Flow Sensor

Claims

1. A geothermal heat recovery heat pump system comprising a geothermal heat source that performs heat extraction and release, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat transfer medium between the geothermal heat source and the geothermal heat source, A thermal energy storage power generation system that stores input power as heat and can output the stored heat as output power, A return pipe through which the heat transfer medium moves from the thermal energy storage power generation system and the multiple geothermal heat pumps to the geothermal heat source, A supply pipe through which the heat transfer medium moves from the aforementioned geothermal heat source to the thermal energy storage power generation system and the multiple geothermal heat pumps, A bypass pipe that merges with the supply pipe and carries the heat transfer medium from the thermal energy storage power generation system and the multiple geothermal heat pumps to the supply pipe, Equipped with, A geothermal energy recovery heat pump system in which the temperature of the heat medium at the point where the bypass pipe merges with the supply pipe is controlled to be equal to the temperature of the heat medium entering the supply pipe from the geothermal heat source.

2. The aforementioned heat storage power generation system is A first converter that converts the input power into heat, A heat storage device that stores the heat converted by the first converter, A geothermal heat recovery heat pump system according to claim 1, comprising a second converter that converts the heat stored in the heat storage device into electricity to obtain the output power.

3. The aforementioned heat storage power generation system further comprises a third converter that converts the input power into heat, The third converter is an air-cooled heat pump. The geothermal energy recovery heat pump system according to claim 2.

4. The aforementioned thermal energy storage power generation system further comprises a cooling auxiliary heat source. The geothermal energy recovery heat pump system according to claim 2.

5. The aforementioned heat storage power generation system is The heat transfer medium cooled by the first converter is discharged to at least one of the return pipe and the bypass pipe. The geothermal energy recovery heat pump system according to claim 2, wherein the heat transfer medium heated by the second converter is discharged to at least one of the return pipe and the bypass pipe.

6. The geothermal heat recovery heat pump system according to claim 1, wherein the input power is generated by renewable energy.

7. The geothermal heat recovery heat pump system according to claim 1, further comprising an auxiliary heat source to supplement the aforementioned geothermal heat source.

8. The first and second converters of the thermal energy storage power generation system are equipped with a switching valve between the return pipe and the bypass pipe. Each of the aforementioned geothermal heat pumps is equipped with a control valve between the return pipe and the bypass pipe. The total amount of heat extracted and released from the first converter, the second converter, and the multiple geothermal heat pumps of the thermal energy storage power generation system is compared. If the amount of heat extracted is greater, the switching valve of the first converter is controlled to flow the heat transfer medium into the return pipe, and the switching valve of the second converter is controlled to flow it into the bypass pipe. If the amount of heat released is greater, the switching valve of the first converter is controlled to flow the heat transfer medium into the bypass pipe, and the switching valve of the second converter is controlled to flow it into the return pipe. The control valve of the ground source heat pump through which the heat transfer medium with the lower heat extraction / dissipation capacity passes is controlled to allow the heat transfer medium to flow through the bypass pipe. The ground source heat recovery heat pump system according to any one of claims 2 to 5, wherein the control valve of the ground source heat pump through which the heat transfer medium with a larger heat extraction / discharge capacity passes is controlled so that the temperature of the heat transfer medium at the point where the bypass pipe merges with the supply pipe is equal to the temperature of the heat transfer medium entering the supply pipe from the ground heat source.

9. The geothermal heat recovery heat pump system according to claim 8, wherein the control valve is a proportional control valve.

10. A method for designing a geothermal heat recovery heat pump system according to claim 2, A first heat storage capacity determination step, which determines the heat storage capacity of the heat storage device to be obtained under predetermined conditions based on the output of the first converter and the output of the second converter, After the first heat storage capacity determination step, a first setting step is performed in which the output of the pre-set second converter is set as output A, and the heat storage capacity determined in the first heat storage capacity determination step is set as heat storage capacity A. A second setting step of setting output B, which is the output of the second converter and is smaller than output A, A second heat storage capacity determination step in which the heat storage capacity obtained under the predetermined conditions is determined based on the output B, and the determined heat storage capacity is set as the heat storage capacity B, A comparison step of comparing the heat storage capacity A and the heat storage capacity B, Equipped with, As a result of the comparison step, in the first case where the heat storage capacity B is larger than the heat storage capacity A, the output A and the heat storage capacity A are adopted. In cases other than the first case, the output B is set as the new output A, and the second heat storage capacity determination step and the comparison step are repeated. Design method.

11. At least one of the first heat storage capacity determination step and the second heat storage capacity determination step is A process for calculating surplus power for each time period, A heat storage amount calculation step that calculates the amount of heat stored for each time period based on the amount of surplus power for each time period, The system includes a maximum heat storage amount determination step, which compares the amount of heat stored at each time point and determines the maximum value of the amount of heat stored at each time point as the heat storage capacity. In the heat storage amount calculation step, if it is determined that the surplus power amount for each time period is negative or zero, the heat storage amount is calculated based on the output of the second converter. The design method according to claim 10.

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