Geothermal heat recovery heat pump system, and operation method of geothermal heat recovery heat pump system

Abstract

To provide a geothermal heat recovery heat pump system capable of efficient operation regardless of a system scale, and operation method thereof.SOLUTION: Provided is a geothermal heat recovery heat pump system 1 that includes a geothermal heat source for collecting and releasing heat, and a plurality of GSHP units 10 performing heat load treatment by circulating a heat medium between GSHP units and the geothermal heat source, the heat pump including: a first regulating valve 41 and a second regulating valve 42 capable of adjusting the flow rate of the heat transfer medium passing through; a first return pipe 21a through which a heated heat transfer medium flows from a plurality of GSHP units 10 to the first regulating valve 41; a second return pipe 21b through which a cooled heat transfer medium flows from the plurality of GSHP units 10 to the second regulating valve 42; an outflow pipe 22 through which a heat transfer medium flows from a geothermal heat source to the plurality of GSHP units 10; a third return pipe 21c through which a heat transfer medium flows from the first regulating valve 41 and the second regulating valve 42 to the geothermal heat source; and a bypass pipe 23 through which a heat transfer medium flows from the first regulating valve 41 and the second regulating valve 42 to the outflow pipe 22.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a geothermal heat recovery heat pump system and a method for operating a geothermal heat recovery heat pump system. [Background technology]

[0002] For example, Patent Documents 1 and 2 describe geothermal heat recovery heat pump systems that perform bypass control. [Prior art documents] [Patent documents]

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

[0004] However, conventional geothermal heat recovery heat pump systems measure the amount of heat collected and released from each of multiple GSHPs, consolidate the measurement results, and perform centralized control using, for example, a control unit.In this centralized control, it was necessary to control for each GSHP whether the heat transfer medium after passing through the GSHP should flow into the return pipe or the bypass pipe. Such systems have the problem that it is difficult to centrally control multiple GSHPs when they are installed in multiple buildings, for example, due to the large scale of the system.

[0005] The present disclosure has been made in consideration of these problems, and aims to provide a geothermal heat recovery heat pump system that can be operated efficiently regardless of the scale of the system, and a method for operating a geothermal heat recovery heat pump system. [Means for solving the problem]

[0006] A geothermal heat recovery heat pump system according to one embodiment of the present disclosure is a geothermal heat recovery heat pump system comprising a geothermal heat source that extracts and releases heat, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source and the geothermal heat pumps, and further comprising: a first regulating valve and a second regulating valve that can adjust the flow rate of the heat medium passing through; a first return pipe through which a heated heat medium moves from the plurality of geothermal heat pumps to the first regulating valve; a second return pipe through which a cooled heat medium moves from the plurality of geothermal heat pumps to the second regulating valve; a supply pipe through which the heat medium moves from the geothermal heat source to the plurality of geothermal heat pumps; a third return pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the geothermal heat source; and a bypass pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the supply pipe. A geothermal heat recovery heat pump system according to another aspect of the present disclosure is a geothermal heat recovery heat pump system including a geothermal heat source that extracts and releases heat, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source and the geothermal heat pump, and includes an adjustment mechanism that adjusts the flow rate of the heat medium passing through, a first return pipe through which a heated heat medium moves from the plurality of geothermal heat pumps to the adjustment mechanism, a second return pipe through which a cooled heat medium moves from the plurality of geothermal heat pumps to the adjustment mechanism, a supply pipe through which the heat medium moves from the geothermal heat source to the plurality of geothermal heat pumps, a third return pipe through which the heat medium moves from the adjustment mechanism to the geothermal heat source, and a bypass pipe through which the heat medium moves from the adjustment mechanism to the supply pipe. A method for operating a geothermal heat recovery heat pump system according to one embodiment of the present disclosure includes a control process for controlling the first regulating valve and the second regulating valve based on a comparison between the amount of heat extracted by the heat medium passing through the first return pipe and the amount of heat released by the heat medium passing through the second return pipe, wherein the control process controls the heat medium with the smaller amount of heat extracted and released to flow into the bypass pipe, and the heat medium with the larger amount of heat extracted and released to be diverted to the bypass pipe and the third return pipe. A geothermal heat recovery heat pump system according to another aspect of the present disclosure is a geothermal heat recovery heat pump system comprising a geothermal heat recovery heat source network that collects and releases heat, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat recovery heat source network, and further comprising: a first regulating valve and a second regulating valve that can adjust the flow rate of the heat medium passing through; a first return pipe through which a heated heat medium moves from the plurality of geothermal heat pumps to the first regulating valve; a second return pipe through which a cooled heat medium moves from the plurality of geothermal heat pumps to the second regulating valve; a feed pipe through which the heat medium moves from the geothermal heat recovery heat source network to the plurality of geothermal heat pumps; a third return pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the geothermal heat recovery heat source network; and a bypass pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the feed pipe. A geothermal heat recovery heat pump system according to another aspect of the present disclosure includes a geothermal heat source that extracts and releases heat, and a geothermal heat pump group having a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source and the geothermal heat pump group, the geothermal heat recovery heat pump system including a first regulating valve and a second regulating valve that can adjust the flow rate of the heat medium passing through the geothermal heat pump group, and a heat medium circulating valve that circulates the heated heat medium from the geothermal heat pump group to the first regulating valve. a second return pipe through which the cooled heat medium moves from a geothermal heat pump group having the plurality of geothermal heat pumps to the second regulating valve; an outgoing pipe through which the heat medium moves from the geothermal heat source to the geothermal heat pump group having the plurality of geothermal heat pumps; a third return pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the geothermal heat source; and a bypass pipe through which the heat medium moves from the first regulating valve and the second regulating valve to the outgoing pipe. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a geothermal heat recovery heat pump system that can be operated efficiently regardless of the scale of the system, and a method for operating a geothermal heat recovery heat pump system. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a conceptual diagram of a geothermal heat recovery heat pump system according to an embodiment of the present disclosure. FIG. [Figure 2] 1 is a diagram illustrating a configuration of a geothermal heat recovery heat pump system according to an embodiment of the present disclosure. [Figure 3] FIG. 10 is a conceptual diagram of a combined geothermal heat recovery heat pump system according to a modified example of the present disclosure. [Figure 4] FIG. 10 is a diagram illustrating an example of a group of HPs provided in a combined geothermal heat recovery heat pump system according to a modified example of the present disclosure. [Figure 5] FIG. 1 is a diagram illustrating an example of a group of HPs in a geothermal heat recovery heat pump system that uses well water according to an embodiment of the present disclosure. [Figure 6] FIG. 10 is a conceptual diagram of a combined geothermal heat recovery heat pump system according to a second modified example of the present disclosure. [Figure 7] FIG. 10 is a diagram showing an example of a geothermal heat source provided in a combined geothermal heat recovery heat pump system according to a second modified example of the present disclosure. [Figure 8A] FIG. 10 is a diagram showing an example of a building equipped with a combined geothermal heat recovery heat pump system according to a second modified example of the present disclosure. [Figure 8B] FIG. 10 is a diagram showing an example of a building equipped with a combined geothermal heat recovery heat pump system according to a second modified example of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] A geothermal heat recovery heat pump system and an operating method of the geothermal heat recovery heat pump system according to one embodiment of the present disclosure will be described below with reference to Figures 1 to 8. Note that, hereinafter, a "geothermal heat pump" may be referred to as a "GSHP" or a "heat pump." A "ground heat exchanger" may be referred to as a "GHEX."

[0010] FIG. 1 is a conceptual diagram of a geothermal heat recovery heat pump system according to one embodiment of the present disclosure. FIG. 1 shows the configuration of a geothermal heat recovery heat pump system 1 (hereinafter also referred to as a heat pump system) to be controlled.

[0011] The heat pump system 1 covers the load (heat load) of a load target. The heat pump system 1 includes a geothermal heat exchanger 30A that exchanges heat with a geothermal heat source (soil), multiple heat pumps 10 (GSHP) that circulate a heat medium between the geothermal heat source 30 and the multiple GSHPs 10, a piping system 20 that connects the geothermal heat source 30 and the multiple GSHPs 10, an adjustment mechanism 70 that adjusts the flow rate of the heat medium passing through, and a control unit (not shown) that controls the heat pump system 1. The heat pump system 1 supplies hot or cold heat to the load target. In this embodiment, the adjustment mechanism 70 includes an adjustment valve 40 .

[0012] In this embodiment, the geothermal heat source 30 is placed underground (soil), and heat is extracted from and released into the soil by a geothermal heat exchanger 30A (GHEX). In the following description, a configuration in which the heat pump system 1 includes the GHEX 30A will be described.

[0013] As shown in FIG. 1, the GSHP 10 adjusts the temperature of the heat medium by circulating the heat medium between the GSHP 10 and the GHEX 30A via a piping system 20. The heat pump system 1 of the present embodiment has four GSHPs 10, but the number of GSHPs 10 is not limited to this. The piping system 20 includes outgoing pipes 22 and 22b, a first return pipe 21a, a second return pipe 21b, a third return pipe 21c, and a bypass pipe 23. Note that the outgoing pipe 22b represents the outgoing pipe before merging with the bypass pipe 23, and the outgoing pipe 22 represents the outgoing pipe after merging with the bypass pipe 23.

[0014] FIG. 2 is a diagram illustrating the configuration of a geothermal heat recovery heat pump system according to an embodiment of the present disclosure. FIG. 2 shows the configuration of a heat pump system 1 of this embodiment. The piping system 20 may be provided with a pump P, a flow meter M, and a thermometer T. Measurement results from the flow meter M and the thermometer T may be sent to a control unit. The operation of the pump P may be controlled by the control unit. The outgoing pipe 22 is a pipe to which the heat medium that has passed through the GHEX 30A, the outgoing pipe 22b, and the bypass pipe 23 is supplied, and is a pipe that moves the heat medium to the GSHP 10. The outgoing pipes 22, 22b may be provided with a thermometer T. In this embodiment, the outgoing pipe 22 is provided with a thermometer Ts, and the outgoing pipe 22b is provided with a thermometer Tg. The first return pipe 21a is a pipe that receives the heat medium heated by the GSHP 10 and transfers the heated heat medium to the first adjustment valve 41. The second return pipe 21b is a pipe that receives the heat medium cooled by the GSHP 10 and transfers the cooled heat medium to the second adjustment valve . The heated heat medium is a heat medium whose temperature is higher after passing through the GSHP 10 than before, for example, due to the cold operation of the GSHP 10. The cooled heat transfer medium is a heat transfer medium whose temperature is lower after passing through the GSHP 10 than before, for example, due to the heating operation of the GSHP 10. The temperature of the heat medium may be obtained by a thermometer T. The temperature of the heat medium obtained by the thermometer T may be determined by, for example, a control unit.

[0015] The heat pump system 1 of this embodiment includes two GSHPs 10A (cooling / heating switching GSHPs) that can switch between cold-heating operation (cooling) and hot-heating operation (heating), one GSHP 10B dedicated to cold-heating operation (cold-heat-only GSHP), and one GSHP 10C dedicated to hot-heating operation (hot-heat-only GSHP). However, the number of GSHPs 10 installed in the heat pump system 1 and their combinations are not limited to this. Furthermore, when the heat pump system 1 is equipped with multiple GSHPs 10, all of the GSHPs 10 may be located in the same building, some of the GSHPs 10 may be located in different rooms or buildings, or all of the GSHPs 10 may be located in different rooms or buildings.

[0016] A first switching valve 11a is disposed between the cold / hot switching GSHP 10A and the first return pipe 21a, and a second switching valve 11b is disposed between the cold / hot switching GSHP 10A and the second return pipe 21b. When the cooling / heating switching GSHP 10A is operating as a cooling system, the switching valves 11 (first switching valve 11a and second switching valve 11b) are controlled to open the switching valve 11a and close the switching valve 11b, so that the heat medium heated by the cooling / heating switching GSHP 10A is supplied to the first return pipe 21a. When the cooling / heating switching GSHP 10A is operating as a heating system, the switching valves 11 are controlled to close the switching valve 11a and open the switching valve 11b, so that the heat medium cooled by the cooling / heating switching GSHP 10A is supplied to the second return pipe 21b. The control of the switching valve 11 may be performed by, for example, a control unit. The first return pipe 21a to which the heat medium is supplied from the cold-only GSHP 10B or the second return pipe 21b to which the heat medium is supplied from the hot-only GSHP 10C may be provided with a valve 12 that can be opened or closed depending on the operating status of the cold-only GSHP 10B or the hot-only GSHP 10C. The valve 12 may be controlled by, for example, a control unit.

[0017] A first adjustment valve 41 connected to the first return pipe 21a and a second adjustment valve 42 connected to the second return pipe 21b adjust the amount of heat transfer medium that has passed through the first return pipe 21a and the second return pipe 21b, respectively, flowing into the third return pipe 21c and the bypass pipe 23. Specifically, the first return pipe 21a and the second return pipe 21b each have branches for connection to the third return pipe 21c and the bypass pipe 23. The first return pipe 21a is provided with a first adjustment valve 41 between the branching of the first return pipe 21a and the connection to the third return pipe 21c and the bypass pipe 23. The second return pipe 21b is provided with a second adjustment valve 42 between the branching of the second return pipe 21b and the connection to the third return pipe 21c and the bypass pipe 23. One regulating valve 40 (first regulating valve 41 and second regulating valve 42) is provided for each branch, so there are two first regulating valves 41 and two second regulating valves 42. The regulating valves 40 may be proportional regulating valves. Furthermore, the first return pipe 21a has a first temperature sensor T1 at the inlet side of the branch of the first return pipe 21a to measure the temperature of the heat medium in the first return pipe 21a, and the second return pipe 21b has a second temperature sensor T2 at the inlet side of the branch of the second return pipe 21b to measure the temperature of the heat medium in the second return pipe 21b. The first return pipe 21a has a first flow rate sensor M1 at the inlet side of the branch of the first return pipe 21a to measure the flow rate of the heat medium in the first return pipe 21a, and the second return pipe 21b has a second flow rate sensor M2 at the inlet side of the branch of the second return pipe 21b to measure the flow rate of the heat medium in the second return pipe 21b.

[0018] With the above configuration, the amount of heat medium flowing into the third return pipe 21c and the bypass pipe 23 can be controlled by controlling the adjustment valve 40 in accordance with the amount of heat collected and released that is calculated from the temperature of the heat medium that has passed through the outflow pipe 22 measured by the temperature sensor Ts installed on the outflow pipe 22, the temperature and flow rate of the heated heat medium that has passed through the first return pipe 21a measured by the first temperature sensor T1 and the first flow rate sensor M1, and the temperature and flow rate of the cooled heat medium that has passed through the second return pipe 21b measured by the second temperature sensor T2 and the second flow rate sensor M2. This control of the adjustment valve 40 may be performed by, for example, a control unit. Although details will be described later, of the first regulating valve 41 and the second regulating valve 42, the regulating valve 40 through which the heat medium with the smaller amount of heat extraction and release passes is controlled to reduce the flow rate to the third return pipe 21c and allow the heat medium to flow to the bypass pipe 23, while the regulating valve 40 through which the heat medium with the larger amount of heat extraction and release passes adjusts the flow rate of the heat medium to the bypass pipe 23. In this way, the temperature of the heat medium at the point where the bypass pipe 23 joins the outflow pipe 22 is controlled to be equivalent to the temperature of the heat medium entering the outflow pipe 22 from the geothermal heat source 30.

[0019] In this embodiment, the adjustment mechanism 70 has the above-described configuration including the adjustment valve 40, but the configuration of the adjustment mechanism 70 is not limited to the above. At least one of the first regulating valve 41 and the second regulating valve 42 may be installed in a building different from the building in which the multiple geothermal heat pumps 10 are installed.

[0020] The third return pipe 21c is a pipe that receives the heat medium that has passed through the regulating valve 40 and transfers the heat medium to the GHEX 30A. The bypass pipe 23 is a pipe that receives the heat medium after passing through the regulating valve 40 and moves the heat medium to the junction 22a, which is the portion where the supply pipe 22 and the bypass pipe 23 join, without passing through the GHEX 30A. The bypass pipe 23 joins the heated heat medium that has passed through the first return pipe 21a and the cooled heat medium that has passed through the second return pipe 21b, and supplies the combined heat to the supply pipe 22. The bypass pipe 23 is a pipe that mixes heat mediums of different temperatures and directly recovers heat. In other words, the bypass pipe 23 is a pipe that directly recovers heat by mutually recovering exhaust heat from cooling hot exhaust heat and heating cold exhaust heat. A thermometer Tb may be provided in the bypass pipe 23.

[0021] The third return pipe 21c and the outgoing pipe 22b are pipes that send the heat medium to the GHEX 30A after the heat medium from the multiple GSHPs 10 joins together, and send the heat medium coming out of the outlet side of the GHEX 30A to the multiple GSHPs 10. In this embodiment, the third return pipe 21c and the outgoing pipe 22b are pipes that exchange heat with the ground and perform indirect heat recovery.

[0022] The heat pump system 1 of this embodiment further includes an auxiliary heat source 50 that assists the heat collection and release by the geothermal heat source 30. The auxiliary heat source 50 compensates for any shortage in the heat supply of the geothermal heat exchanger 30A. In this embodiment, the auxiliary heat sources 50 include two auxiliary heat sources: an auxiliary cooling heat source 51 and an auxiliary heating heat source 52. Note that the heat pump system 1 does not necessarily have to include the auxiliary heat source 50. In this embodiment, the auxiliary cooling heat source 51 is located on the inlet side of the GHEX 30A, and the auxiliary heating heat source 52 is located on the outlet side of the GHEX 30A.

[0023] In cooling by the GSHP 10, for example, the heat transfer medium temperature is released at a peak of about 35°C, while the outside air temperature is around 30°C and the underground temperature is about 25°C, so the outside air temperature is higher than the underground temperature. In such cases, it is preferable to cool the heat transfer medium in a cooling tower (auxiliary cooling heat source 51) before it enters the ground. The auxiliary cooling heat source 51 is connected to the third return pipe 21c and assists the GHEX 30A when its heat dissipation capacity is insufficient to cover the amount of heat dissipated when the GSHP 10 processes the heat load of the load target. The auxiliary cooling heat source 51 is not limited to a cooling tower and may be, for example, a refrigerator, but since the atmospheric temperature is usually between the warm exhaust heat temperature and the underground temperature, it is preferable to use a cooling tower which consumes less power.

[0024] When heating with the GSHP 10, for example, the heat transfer medium temperature peaks at about 7°C (or below 0°C if antifreeze is used as the heat transfer medium), but the underground temperature can be about 5 to 10°C higher than the heat transfer medium temperature. In such cases, the heat transfer medium after emerging from the underground piping is preferably heated by the auxiliary heating heat source 52. The auxiliary heating heat source 52 is connected to the outflow pipe 22b between the geothermal heat source 30 and the junction 22a where the outflow pipe 22b and the bypass pipe 23 join, and assists the GHEX 30A when its heat extraction capacity is insufficient for the amount of heat extracted when the GSHP 10 processes the heat load of the load target. The auxiliary heating source 52 may be, for example, a boiler, a solar heat storage tank, or a hot wastewater tank.

[0025] [Operating method of heat pump system 1] In this embodiment, a bypass pipe 23 is installed in the heat pump system 1. The flow rate of circulation to the bypass pipe 23 is controlled by the control flow shown below, so that the amount of heat released from the GSHP 10 during cooling operation and the amount of heat collected from the GSHP 10 during heating operation are equalized, and part or all of the larger amount of heat collected or released is recovered before the heat medium is sent to the GHEX 30A.

[0026] In the following, the operation method of the heat pump system 1 and the flow of bypass control will be described using as an example a case where two of the four GSHPs 10 are performing cooling operation and the other two are performing heating operation.

[0027] The operating method of the heat pump system 1 includes a control step of controlling the first regulating valve 41 and the second regulating valve 42 based on a comparison between the amount of heat collected by the heat medium passing through the first return pipe 21a and the amount of heat released by the heat medium passing through the second return pipe 21b. In the control step, the flow rate of the heat medium with the larger amount of collected and released heat to the bypass pipe 23 may be adjusted so that the temperature of the heat medium at the junction where the bypass pipe 23 and the outflow pipe 22b merge is equal to the temperature of the heat medium entering the outflow pipe 22b from the geothermal heat source 30. The amount of heat released by the heat medium may be calculated based on the temperature measured by the thermometer T and the flow rate measured by the flowmeter M. In this case, the calculation result may be sent to the control unit, and the control unit may control the regulating valve 40 and the pump P based on the measurement result to perform the control step. The amount of heat released through the first return pipe 21a is designated Qhp1, and the amount of heat collected through the second return pipe 21b is designated Qhp2. In this embodiment, the heat radiation amount of the heat medium is calculated as follows using the temperature measured by the thermometer T and the flow rate measured by the flow meter M. The heat radiation amount Qhp1 of the heat medium passing through the first return pipe is calculated by (temperature of the heat medium inside the supply pipe 22 - temperature of the heat medium passing through the first return pipe 21a) x flow rate of the heat medium passing through the first return pipe 21a. The amount of heat collected by the heat medium passing through the second return pipe Qhp2 = (temperature of the heat medium inside the supply pipe 22 - temperature of the heat medium passing through the second return pipe 21b) × flow rate of the heat medium passing through the second return pipe 21b...Equation (B) When calculating the heat release amount Qhp1 and the heat collection amount Qhp2, and when determining whether the system is in cold heat supply / heat release operation or hot heat supply / heat collection operation, the heat medium temperature inside the supply pipe is the heat medium temperature before the heat medium is diverted to the heat pump, and the heat medium temperature after passing through the return pipe is the heat medium temperature after the heat medium from all the heat pumps has been combined. An example of bypass control will be described below.

[0028] (1) The heat dissipation amount at the outlet side of each of the two GSHP10 units operating in cooling mode is assumed to be Qhp1,1 and Qhp1,2, respectively. The heat extraction amount at the outlet side of each of the two GSHP10 units operating in heating mode is assumed to be Qhp2,1 and Qhp2,2, respectively. Here, the heat release amount Qhp1 is the total heat release amount of the heat release amounts Qhp1,1 and Qhp1,2, and the heat collection amount Qhp2 is the total heat collection amount of the heat collection amounts Qhp2,1 and Qhp2,2. In the operating method of this embodiment, subsequent control is performed using the total heat release amount Qhp1 that has passed through the first return pipe 21a and the total heat collection amount Qhp2 that has passed through the second return pipe 21b, so it is not necessary to measure the heat collection and release amounts for each GSHP 10, i.e., the heat release amounts Qhp1,1 and Qhp1,2 and the heat collection amounts Qhp2,1 and Qhp2,2. (2) Compare the absolute values ​​of the heat loss Qhp1 and heat collection Qhp2. (3) If Qhp1 is greater than Qhp2, control is performed in the following manner. Of the second regulating valves 42 connected to the second return pipe 21b, the second regulating valve 42a installed in the flow path to the bypass pipe 23 is fully opened, and the second regulating valve 42b installed in the third return pipe 21c is fully closed, thereby sending all of the heat medium (flow rate M2) that has passed through the second return pipe 21b to the bypass pipe 23. At the same time, the first regulating valve 41a installed in the flow path to the bypass pipe 23 of the first regulating valves 41 connected to the first return pipe 21a adjusts the amount m1 of the heat medium that has passed through the first return pipe 21a and is sent to the bypass pipe 23, thereby controlling the amount of heat radiation flowing into the bypass pipe 23 from the return pipe 21a to be equal to the amount of heat collected flowing in from the return pipe 21b, and heat is directly recovered in the bypass pipe 23. In direct heat recovery, as in this embodiment, it is preferable to adjust the flow rate of the heat medium with the greater amount of heat collected and released into the bypass pipe 23 so that the temperature of the heat medium at the point where the bypass pipe 23 merges with the supply pipe 22b (confluence point) is equivalent to the temperature of the heat medium entering the supply pipe 22b from the geothermal heat source 30 (temperature control).However, by controlling the amount of heat, for example, the flow rate m1 of the heat medium that has passed through the first return pipe 21a and is sent to the bypass pipe 23 may be adjusted as follows. When the heat transfer amount of the heat transfer medium that has passed through the first return pipe 21a and is made to flow into the bypass pipe 23 is Qhpb1, the heat transfer amount Qhpb1 of the heat transfer medium that has passed through the bypass pipe 23 is calculated by the following formula (C). The heat radiation amount Qhpb1 of the heat medium flowing into the bypass pipe 23 = (temperature of the heat medium inside the supply pipe 22 - temperature of the heat medium that has passed through the first return pipe 21a) × flow rate m1 of the heat medium flowing into the bypass pipe 23 Equation (C) The flow rate m1 of the heat medium that has passed through the first return pipe 21a and is sent to the bypass pipe 23 is adjusted so that the absolute value of Qhpb1=the absolute value of Qhp2. Note that when Qhp2 = 0, the flow rate M2 of the heat transfer medium in the return pipe 21b becomes 0. As long as the absolute value of Qhp1 is greater than the absolute value of Qhp2, the adjustment valve 42a remains fully open, but since M2 = 0, no bypass flow rate m2 from the return pipe 21b occurs. Therefore, when Qhp2 = 0, direct heat recovery cannot be performed in the bypass pipe 23, so the adjustment valve 41a is fully closed and the adjustment valve 41b is fully open, and the entire amount of the heat transfer medium flowing through the first return pipe 21a is sent to the third return pipe 21c. (4) If Qhp2 is greater than Qhp1, control is performed in the following manner. Of the first regulating valves 41 connected to the first return pipe 21a, the first regulating valve 41a installed in the flow path to the bypass pipe 23 is fully opened, and the first regulating valve 41b installed in the third return pipe 21c is fully closed, thereby sending all of the heat medium (flow rate M1) that has passed through the first return pipe 21a to the bypass pipe 23. At the same time, of the second regulating valves 42 connected to the second return pipe 21b, the second regulating valve 42a installed in the flow path to the bypass pipe 23 adjusts the amount m2 of the heat medium that has passed through the second return pipe 21b and is sent to the bypass pipe 23, thereby controlling the amount of collected heat flowing into the bypass pipe 23 from the return pipe 21b to be equal to the amount of heat released flowing in from the return pipe 21a, and heat is directly recovered in the bypass pipe 23. Of the heat transfer medium that has passed through the second return pipe 21b, the flow rate m2 of the heat transfer medium that is sent to the bypass pipe 23 may be adjusted as follows. When the heat transfer amount of the heat transfer medium that has passed through the second return pipe 21b and is made to flow into the bypass pipe 23 is Qhpb2, the heat transfer amount Qhpb2 of the heat transfer medium that has passed through the bypass pipe 23 is calculated by the following formula (D). The amount of heat collected by the heat medium flowing into the bypass pipe 23, Qhpb2 = (temperature of the heat medium inside the supply pipe 22 - temperature of the heat medium that has passed through the second return pipe 21b) × flow rate of the heat medium flowing into the bypass pipe 23, m2... Equation (D) The flow rate m2 of the heat transfer medium that has passed through the second return pipe 22b and is sent to the bypass pipe 23 is adjusted so that the absolute value of Qhpb2=the absolute value of Qhp1. When Qhp1 = 0, the flow rate M1 of the heat transfer medium in the return pipe 21a becomes 0. As long as the absolute value of Qhp2 is greater than the absolute value of Qhp1, the adjustment valve 41a remains fully open, but since M1 = 0, no bypass flow rate m2 from the return pipe 21a occurs. Therefore, when Qhp1 = 0, direct heat recovery cannot be performed in the bypass pipe 23, so the adjustment valve 42a is fully closed and the adjustment valve 42b is fully open, and the entire amount of the heat transfer medium flowing through the second return pipe 21b is sent to the third return pipe 21c.

[0029] As described above, it is possible to maximize direct heat recovery by mixing the heat transfer medium containing the heat release amount generated by the cooling operation of the GSHPs 10A and 10C with the heat transfer medium containing the heat collection amount generated by the heating operation of the GSHPs 10A and 10B, while minimizing indirect heat recovery by recovering heat through heat exchange with the remaining heat transfer medium from the geothermal heat source 30. By minimizing indirect heat recovery, it is possible to minimize the amount of heat collection and release between the heat transfer medium and geothermal heat, thereby improving the efficiency and cost performance of the heat pump system 1 as a whole.

[0030] In the above-described operating method, the heat medium with the smaller absolute value of the heat release amount Qhp1 or the heat collection amount Qhp2 is entirely sent to the bypass pipe 23, but the operating method is not limited to this. It is sufficient that the heat mediums are mixed in the bypass pipe 23 based on the respective heat collection and release amounts of the heat mediums inside the first return pipe 21a and the second return pipe 21b, and direct heat recovery is performed.

[0031] Next, a modified example of the heat pump system will be described. FIG. 3 is a conceptual diagram of a combined geothermal heat recovery heat pump system according to a modified example of the present disclosure. The combined heat pump system 100A of the modified example is used, for example, when a geothermal heat source 30 is utilized locally. In Fig. 3, the HP groups indicated as "HP group (1)" to "HP group (3)" are applied to buildings having the heat pump systems 1, 200 of Fig. 4(a) or Fig. 4(b), for example. Note that the portion indicated as the HP group in Fig. 3 may be applied to a single heat pump, for example, when the target is a small building.

[0032] In the following, an example will be described in which a building 140 having the heat pump system 1, 200 shown in FIG. 4(a) or 4(b) is applied to the HP group of the combined heat pump system 100A. 4(a) and 4(b) are diagrams showing an example of a group of HPs provided in a combined geothermal heat recovery heat pump system according to a modified example of the present disclosure. The heat pump system 200 shown in FIG. 4(a) has one bypass pipe 223 and one return pipe 221, measures the amount of heat collected and released for each GSHP 10, and selects the pipe into which the heat medium flows after passing through. The heat pump system shown in Figure 4(b) is the heat pump system 1 of the present disclosure, and has one bypass pipe 23 and first to third return pipes 21a, 21b, and 21c. The amount of heat collected and released may be measured by a temperature sensor or flow meter (not shown), and the flow rate may be controlled by a regulator valve, pump, or controller (not shown). As shown in FIGS. 4(a) and 4(b), the return pipe 221 of the heat pump system 200 or the third return pipe 21c of the heat pump system 1 incorporated in the combined heat pump system 100A has a switching valve 60 before connecting to the connection point B of the first return pipe 121a or the connection point C of the second return pipe 121b of the combined heat pump system 100A. This controls whether the heat medium passing through the heat pump system 1, 200 is sent to the first return pipe 121a or the second return pipe 121b of the combined heat pump system 100A, depending on whether the heat pump system 200 is in a cold heat supply / heat release operation state or a hot heat supply / heat extraction operation state. The amount of heat extraction and release may be calculated based on the temperature and flow rate measured by a temperature sensor and a flow meter (not shown). The flow rate may be controlled by a regulator valve, pump, or control unit (not shown). Whether the heat pump system 200 incorporated in the combined heat pump system 100A is in a cold heat supply / heat radiation operation state or a hot heat supply / heat extraction operation state can be determined if the temperature of the heat medium in the return pipe 221 minus the temperature of the heat medium in the supply pipe 222 is positive, or if the result is negative, it is determined to be a hot heat supply / heat extraction operation state. Whether the heat pump system 1 incorporated in the combined heat pump system 100A is in a cold heat supply / heat radiation operation state or a hot heat supply / heat extraction operation state can be determined if the temperature of the heat medium in the return pipe 21c minus the temperature of the heat medium in the supply pipe 22 is positive, or if the result is negative, it is determined to be a cold heat supply / heat radiation operation state.

[0033] Regardless of whether the heat pump system shown in FIG. 4(a) or (b) is used, the piping of the combined heat pump system 100A and the piping of the heat pump systems 1 and 200 of the HP group are connected as follows.

[0034] The outgoing pipe 122 of the combined heat pump system 100A is connected at a connection point A to the outgoing pipes 22, 222 of the HP group. The first return pipe 121a of the combined heat pump system 100A is connected to the first branch return pipe 61 of the HP group at a connection point B. The second return pipe 121b of the combined heat pump system 100A is connected to the second branch return pipe 62 of the HP group at a connection point C.

[0035] Comparing the heat pump system in Fig. 1 with the HP groups in Fig. 4(a)(b), the heat pump system in Fig. 1 is directly connected to a geothermal heat source, whereas the HP groups in Fig. 4(a)(b) are connected to a geothermal heat source via the heat source piping network shown in Fig. 3. Hereinafter, this heat source piping network to which the HP groups are connected, and the piping network including the geothermal heat source, auxiliary heat source, and regulating valve excluding the HP groups from the heat pump system 100A will be referred to as the geothermal heat recovery heat source network 150.

[0036] In the above, a case where a building 140 is used as a group of HPs has been described, but instead of the building 140, for example, a group of buildings in the same block (a section that constitutes an urban area and is surrounded by streets) may be grouped together as a single system to form a group of HPs. In this case, one of the groups of HPs shown in Fig. 3 may become a combined heat pump system 100A that includes a group of HPs in a lower-level block.

[0037] Up to this point, the case where the geothermal heat source 30 is underground (soil) has been described, but the geothermal heat source 30 may be, for example, well water. FIG. 5 is a diagram illustrating an example of a group of HPs included in a geothermal heat recovery heat pump system that uses well water according to an embodiment of the present disclosure. FIG. 5 shows a heat pump system 100B in which well water is used as the geothermal heat source 30. Geothermal energy can be utilized indirectly through pipe walls, as in the geothermal heat exchanger 30A, where a heat medium flows through heat exchange pipes inserted underground, and the heat is exchanged indirectly through the pipe walls (indirect method), as well as through open-loop methods (direct method) that directly circulate groundwater, such as well water. For large-scale heat pump systems, direct methods like well water use are preferable because they are more cost-effective than indirect methods like the geothermal heat exchanger 30A. However, there are many design considerations, such as the need to pass groundwater through a heat pump directly, due to concerns about corrosion prevention depending on the water quality. Furthermore, there are many design issues to consider, such as the need to pass the water through a heat exchanger, and the difficulty of pressure management due to the open piping system. Furthermore, pumping restrictions are imposed in some areas, so caution is required when adopting this method. In the case of an open loop system that directly recycles groundwater, such as well water use, a well water facility 30B may be provided. The well water facility 30B is composed of a pumping well 31 with a pumping pump 31a and a reinjection well 32 that returns the heat source water after heat utilization to groundwater. The pumping well 31 pumps up groundwater, uses it as a heat medium, and then returns the heat source water after heat utilization to the groundwater in the reinjection well 32.

[0038] Furthermore, when a group of buildings in the same block (a section that makes up an urban area and is surrounded by streets) are grouped together as a single system to form an HP group, rather than building 140, as in the above-mentioned combined heat pump system 100A, the heat pump systems in each building may not individually exchange heat with the geothermal heat source 30, but heat exchange may be performed using a single geothermal heat source 30 (common geothermal heat source 33) that is centrally installed throughout the combined heat pump system 100A, or a configuration having individual geothermal heat sources 34 installed in a distributed manner may be adopted, for example, as follows.

[0039] FIG. 6 is a conceptual diagram of a combined geothermal heat recovery heat pump system according to a second modification of the present disclosure. Similar to the first modification, the combined heat pump system 100C of the second modification is used, for example, when a geothermal heat source 30 is used locally. The combined heat pump system 100C of the second modification has a geothermal heat recovery heat source network 150. In this embodiment, the geothermal heat recovery heat source network 150 includes a common geothermal heat source 33 and individual geothermal heat sources 34 connected to the common geothermal heat source 33. The HP group is, for example, a building 140 shown in FIG. 4(a) or 4(b).

[0040] In the first modified example, just as the HP group 141 was connected to the geothermal heat recovery heat source network 150, the individual geothermal heat sources 34 are connected to the return pipe 121c and the supply pipe 22 of the combined heat pump system 100C, and the individual geothermal heat sources 34 are connected to the geothermal heat recovery heat source network 150, so that all of the HP groups 141 in the combined heat pump system 100C can exchange heat with the individual geothermal heat sources 34 in addition to the common geothermal heat source 33. In this way, with a configuration that includes the geothermal heat recovery heat source network 150, even if new HP groups 141 are connected, the geothermal heat source capacity is increased by adding the individual geothermal heat sources 34 in addition to the common geothermal heat source 33, and then the heat load is processed by circulating the heat medium, so there is no shortage of geothermal heat source capacity and the combined heat pump system 100C can be expanded. For example, the addition of the HP group 141 and the geothermal heat source 30 will be described using an example in which only the HP group (1) and the common geothermal heat source 33 in Figure 6 are installed when the heat pump system is first constructed. Note that one or more HP groups 141 may be installed in the heat pump system 100C. Furthermore, the geothermal heat source 30 may be installed in multiple locations rather than centrally in a single location. When the HP group 141 is to be installed, if there is a surplus in the heat extraction and release capacity of the common geothermal heat source 33 and the heat extraction and release amount for the additional HP group (2) can be covered within that capacity, then it is sufficient to simply connect the HP group (2) to the supply pipe 122 and the return pipes 121a and 121b. When an additional HP group 141 is to be installed, if the heat extraction and release capacity of the common geothermal heat source 33 is insufficient, the HP group (2) can be connected to the supply pipe 122 and the return pipes 121a and 121b, and additional individual geothermal heat sources (1) 34 with the required heat extraction and release capacity can be installed somewhere within the geothermal heat recovery heat source network 150, and the individual geothermal heat source (1) 34 can be connected to the return pipe 121c and the supply pipe 122b. Also, if space for installing the individual geothermal heat sources 34 can be secured under the building or on the premises where the additional HP group is to be installed, the individual geothermal heat source (2) 34 can be installed under the building or on the same premises where the additional HP group (3) is to be installed, and the individual geothermal heat source (1) 34 can be connected to the return pipe 121c and the supply pipe 122b.

[0041] The individual geothermal heat sources 34 connected to the geothermal heat recovery heat source network 150 in the combined heat pump system 100C will be described below using FIG. 7(a) or (b) as an example. 7(a) illustrates a case where a GHEX 30A is used as the individual geothermal heat source 34. This embodiment includes an outgoing pipe 22c through which a heat medium flows from the GHEX 30A to the geothermal heat recovery heat source network 150, and a return pipe 21d through which a heat medium flows from the geothermal heat recovery heat source network 150 to the GHEX 30A. The outgoing pipe 22c is connected to an outgoing pipe 122b of the geothermal heat recovery heat source network 150 at a connection point D. The return pipe 21d is connected to a return pipe 121c of the geothermal heat recovery heat source network 150 at a connection point E. 7(b) illustrates a case where well water facility 30B is used as individual geothermal heat source 34. This embodiment includes an outgoing pipe 22c through which a heat medium flows from well water facility 30B to geothermal heat recovery heat source network 150, and a return pipe 21d through which a heat medium flows from geothermal heat recovery heat source network 150 to well water facility 30B. Outgoing pipe 22c is connected to outgoing pipe 122b of geothermal heat recovery heat source network 150 at connection point D. Return pipe 21d is connected to return pipe 121c of geothermal heat recovery heat source network 150 at connection point E.

[0042] In the following, an example will be described in which a building 140 having the heat pump system 1, 200 shown in FIG. 8A or FIG. 8B is applied as the building of the combined heat pump system 100C. The building 140 includes a group of HPs 141 and individual geothermal heat sources 34 .

[0043] 8A and 8B are diagrams showing an example of a building 140 equipped with a combined geothermal heat recovery heat pump system 100C according to a second modification of the present disclosure. 8A shows a case where the HP group in the building 140 is the heat pump system 200 shown in FIG. 4(a), and the individual geothermal heat source 34 includes a GHEX 30A in which the geothermal heat source 30 is underground (soil), but is not limited to this. The geothermal heat source 30 may be, for example, well water. 8B shows a case in which the HP group in the building 140 is the heat pump system 1 of the present disclosure shown in FIG. 4(b), and the individual geothermal heat source 34 includes a well water facility 30B in which the geothermal heat source 30 used is well water, but is not limited to this. The geothermal heat source 30 used may be underground (soil), for example. 8A and 8B, the individual geothermal heat source 34 is installed in the same location as the building 140 that has the group of HPs, but it may also be installed in a location separate from the building 140 that has the group of HPs.

[0044] The building 140, the group of HPs 141, and the individual geothermal heat sources 34 shown in FIGS. 8A and 8B correspond to the building 140, the group of HPs 141, and the individual geothermal heat sources 34 shown in FIG.

[0045] Regardless of whether the heat pump system of FIG. 8A or FIG. 8B is used, the piping of the combined heat pump system 100C and the piping of the heat pump systems 1, 200 of the building 140 are connected as follows.

[0046] The supply pipe 122b of the combined heat pump system 100C is connected to the common geothermal heat source 33 and the individual geothermal heat source 34 of the building 140 at a connection point A. The third return pipe 121c of the combined heat pump system 100C is connected to the common geothermal heat source 33 and the individual geothermal heat source 34 at a connection point E. The first return pipe 121a of the combined heat pump system 100C is connected to the first branch return pipe 61 of the HP group 141 at a connection point B. The second return pipe 121b of the combined heat pump system 100A is connected to the second branch return pipe 62 of the HP group 141 at a connection point C.

[0047] As described above, the heat pump systems 1, 100A, 100B, and 100C of the present disclosure are heat pump systems 1, 100A, 100B, and 100C that include a geothermal heat source 30 that collects and releases heat, and a plurality of GSHPs 10 that perform heat load processing by circulating a heat medium between the geothermal heat source 30 and the geothermal heat source 30, and include a first regulating valve 41 and a second regulating valve 42 that can adjust the flow rate of the heat medium passing through, and a first regulating valve 42 through which the heated heat medium moves from the plurality of GSHPs 10 to the first regulating valve 41. the first return pipes 21a, 121a, second return pipes 21b, 121b through which the cooled heat transfer medium moves from the multiple GSHPs 10 to the second regulating valve 42, outgoing pipes 22, 122 through which the heat transfer medium moves from the geothermal heat source 30 to the multiple GSHPs 10, third return pipes 21c, 121c through which the heat transfer medium moves from the first regulating valve 41 and the second regulating valve 42 to the geothermal heat source 30, and bypass pipes 23, 123 through which the heat transfer medium moves from the first regulating valve 41 and the second regulating valve 42 to the outgoing pipes 22, 122. In heat pump systems 1, 100A, 100B, and 100C, based on the total heat extraction and release amounts of multiple GSHPs 10, a portion of the heat extraction and release amount is used for direct heat recovery, thereby minimizing the heat load processing by the geothermal heat source 30, thereby enabling more efficient heat pump operation and improved system cost performance. In the above configuration, for example, it is determined whether each of the multiple GSHPs 10 is operating in cold heat supply / heat radiation operation or hot heat supply / heat extraction operation, and if it is determined that cold heat supply / heat radiation operation is being performed, the heated heat medium is caused to flow into the first return pipes 21a, 121a, and if it is determined that hot heat supply / heat extraction operation is being performed, the cooled heat medium is caused to flow into the second return pipes 21b, 121b. Simply by calculating the amount of heat extracted by the heat medium passing through the first return pipes 21a, 121a (total extracted heat amount) and the amount of heat released by the heat medium passing through the second return pipes 21b, 121b (total released heat amount), it is possible to control the flow rate of the heat medium to the bypass pipe 23 and the third return pipe 21c using the first adjustment valve 41 and the second adjustment valve 42, and a portion of the total amount of heat extracted and released by the multiple GSHPs 10 can be used directly for heat recovery. For this reason, even if multiple GSHPs 10 are installed distributed across multiple buildings, such as in the case of large-scale heat pump systems 1, 100A, 100B, and 100C, highly efficient operation is possible without the need for centralized control, including measuring the amount of heat collected and released by each GSHP 10 and aggregating the measurement results. Therefore, the geothermal heat recovery heat pump systems 1, 100A, 100B, and 100C can be operated efficiently regardless of the system scale.

[0048] Furthermore, of the first regulating valve 41 and the second regulating valve 42, the regulating valve through which the heat medium with the smaller amount of heat extraction and release passes may be controlled to reduce the flow rate to the third return pipe 21c, 121c and allow the heat medium to flow to the bypass pipe 23, and the regulating valve through which the heat medium with the larger amount of heat extraction and release passes may be controlled by adjusting the flow rate of the heat medium to the bypass pipe 23 so that the temperature of the heat medium at the point where the bypass pipe 23 joins the supply pipes 22, 122 is equivalent to the temperature of the heat medium entering the supply pipes 22, 122 from the geothermal heat source 30. With this configuration, by controlling the first adjustment valve 41 and the second adjustment valve 42, the ratio between the amount of heat medium flowing from the first return pipes 21a, 121a and the second return pipes 21b, 121b into the bypass pipe 23 and the amount of heat medium flowing from the first return pipes 21a, 121a and the second return pipes 21b, 121b into the third return pipe 21c can be adjusted, so that the temperature of the heat medium passing through the bypass pipe 23 can be made approximately equal to the temperature of the heat medium on the inlet side of the junction. This means that part of the heat radiation amount occurring on the return pipes 21a, 121a side and the heat collection amount occurring on the return pipes 21b, 121b side are mutually recovered. Therefore, the amount of heat radiation generated on the return pipes 21a and 121a side is subtracted by an amount equal to the amount of heat collected on the return pipes 21b and 121b side, and only the remaining amount is sent to the return pipes 21c and 121c for heat exchange in the geothermal heat source 30. This allows for a reduction in the volume of the geothermal heat source 30, i.e., the number of geothermal heat exchangers (GHEX) 30A and the amount of water pumped by the well equipment 30B. This allows for significant cost reductions regardless of the system size. Furthermore, by limiting the reduction in the volume of the geothermal heat source 30 to a certain extent, changes in the underground temperature, which is the heat source, can be mitigated, resulting in a geothermal heat recovery heat pump system 1, 100A, 100B, or 100C that can operate more efficiently regardless of the system size.

[0049] Moreover, the first regulating valve 41 and the second regulating valve 42 may be proportional regulating valves. With this configuration, by controlling the flow rate of the heat medium with the proportional control valve, it is easy to make the temperature of the heat medium flowing through the bypass pipe 23 equal to the temperature of the heat medium flowing through the outflow pipes 22b, 122b. Therefore, it is possible to provide geothermal heat recovery heat pump systems 1, 100A, 100B, 100C that can operate more efficiently regardless of the scale of the system.

[0050] The heat pump systems 1, 100A, 100B, and 100C are geothermal heat recovery heat pump systems 1, 100A, 100B, and 100C that include a geothermal heat source 30 that extracts and releases heat, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source 30, and include an adjustment mechanism 70 that adjusts the flow rate of the heat medium passing through, and a first flow control mechanism 70 that moves the heated heat medium from the plurality of geothermal heat pumps 10 to the adjustment mechanism 70. The system may also include return pipes 21a, 121a, second return pipes 21b, 121b through which the cooled heat transfer medium moves from the multiple geothermal heat pumps 10 to the adjustment mechanism 70, supply pipes 22, 122 through which the heat transfer medium moves from the geothermal heat source 30 to the multiple geothermal heat pumps 10, third return pipes 21c, 121c through which the heat transfer medium moves from the adjustment mechanism 70 to the geothermal heat source 30, and bypass pipes 23, 123 through which the heat transfer medium moves from the adjustment mechanism 70 to the supply pipes 22, 122. With this configuration, after the heat medium from all of the geothermal heat pumps 10 flows into the first return pipes 21a, 121a or the second return pipes 21b, 121b, for example, the amount of heat collected by the heat medium that passed through the first return pipes 21a, 121a and the amount of heat released by the heat medium that passed through the second return pipes 21b, 121b are calculated, and the flow rate of the heat medium to the bypass pipe 23 and the third return pipe 21c is controlled by the adjustment mechanism 70, thereby making it possible to directly recover heat within the system the total amount of heat collected and released by the multiple geothermal heat pumps 10. Thus, the geothermal heat recovery heat pump systems 1, 100A, 100B, 100C can be operated efficiently regardless of the scale of the system.

[0051] The geothermal heat source 30 may also be soil. With this configuration, the heat pump can perform heat load processing by collecting and releasing heat from the soil (underground).

[0052] Furthermore, the geothermal heat source 30 may be well water (groundwater). With this configuration, the heat pump can perform heat load processing by using well water as a heat medium and extracting and releasing heat.

[0053] An auxiliary heat source that supplements the geothermal heat source 30 may also be provided. When multiple geothermal heat pumps 10 are operated, for example, if either the amount of heat collected or the amount of heat released becomes excessively large, the geothermal heat source 30 may not be able to sufficiently process the amount of heat collected and released. With the above configuration, for example, the amount of heat collected and released that cannot be fully processed by the geothermal heat source 30 can be processed by the auxiliary heat source, thereby assisting the geothermal heat source 30 in processing the heat load.

[0054] The auxiliary heat source may be a cooling auxiliary heat source that is connected to the third return pipe 21c and assists the geothermal heat pump 10 in treating the heat load of the load target. With this configuration, for example, when the temperature of the heat medium inside the third return pipe 21c is higher than the temperature of the geothermal heat source 30, the heat medium inside the third return pipe 21c can be cooled by an auxiliary cooling heat source such as a cooling tower before it reaches the geothermal heat source 30. Therefore, the heat load treatment by the geothermal heat source 30 can be assisted.

[0055] The auxiliary heat source may be an auxiliary heating heat source that is connected to the supply pipes 22b, 122b between the geothermal heat source 30 and the point where the supply pipes 22, 122 and the bypass pipe 23 join, and assists the geothermal heat pump 10 in processing the heat load of the load target. With this configuration, for example, when the temperature of the heat medium flowing inside the outflow pipes 22, 122 is lower than the temperature of the heat medium required for the heating operation of the geothermal heat pump 10, the auxiliary heating heat source can heat the heat medium. Therefore, the heat load treatment by the geothermal heat source 30 can be assisted.

[0056] The multiple geothermal heat pumps 10 include a cold / hot switching geothermal heat pump 10A that can switch between cold heat supply / heat release operation and hot heat supply / heat extraction operation, and a first switching valve 11a is arranged between the cold / hot switching geothermal heat pump 10A and the first return pipe 21a, and a second switching valve 11b is arranged between the cold / hot switching geothermal heat pump 10A and the second return pipe 21b. With this configuration, even if the system includes a geothermal heat pump 10A that can switch between cold and hot operation, the switching valve 11 can be used to select whether the heat transfer medium flows through the first return pipe 21a or the second return pipe 21b depending on the operating conditions. Specifically, when the geothermal heat pump 10A is operating in cold operation, the first switching valve 11a is opened and the second switching valve 11b is closed, allowing the heated heat transfer medium to flow into the first return pipe. When the geothermal heat pump 10A is operating in hot operation, the first switching valve 11a is closed and the second switching valve 11b is opened, allowing the cooled heat transfer medium to flow into the second return pipe 21b. This allows the geothermal heat recovery heat pump system 1 to operate efficiently.

[0057] At least one of the first regulating valve 41 and the second regulating valve 42 may be installed in a building different from the building in which the multiple geothermal heat pumps 10 are installed. In the heat pump systems 1, 100A, 100B, and 100C of the present disclosure, there is no need to measure and centrally control the heat extraction and release rates for each of the multiple geothermal heat pumps 10. Therefore, at least one of the first regulating valve 41 and the second regulating valve 42 may be located in a building different from the building in which the multiple geothermal heat pumps 10 are installed. With this configuration, the geothermal heat recovery heat pump systems 1, 100A, 100B, and 100C can be large-scale systems spanning multiple buildings. Therefore, the geothermal heat recovery heat pump systems 1, 100A, 100B, and 100C can be operated efficiently regardless of the system scale.

[0058] The system may further include a first temperature sensor T1 that measures the temperature of the heat medium on the inlet side of the first regulating valve 41 and a second temperature sensor T2 that measures the temperature of the heat medium on the inlet side of the second regulating valve 42. With this configuration, the temperature of the heat transfer medium at the inlet side of each regulating valve can be measured. Furthermore, the amount of heat transfer and heat release of the heat transfer medium passing through the first return pipes 21a, 121a and the second return pipes 21b, 121b can be calculated based on the temperature measured by the temperature sensor and the flow rate of the heat transfer medium measured, for example, by a flow meter. This allows for adjustment of the amount of heat transfer medium flowing from the first return pipes 21a, 121a and the second return pipes 21b, 121b into the bypass pipe 23 and the amount of heat transfer medium flowing from the first return pipes 21a, 121a and the second return pipes 21b, 121b into the third return pipe 21c. Therefore, the geothermal heat recovery heat pump systems 1, 100A, 100B, and 100C can be efficiently operated regardless of the system size.

[0059] The operating method of the geothermal heat recovery heat pump systems 1, 100A, 100B, 100C disclosed herein includes a control process for controlling the first regulating valve 41 and the second regulating valve 42 based on the comparison result between the heat extraction amount of the heat medium passing through the first return pipe 21a, 121a and the heat release amount of the heat medium passing through the second return pipe 21b, 121b, and in the control process, the heat medium with the smaller heat extraction and release amount may be controlled to flow into the bypass pipe 23, and the heat medium with the larger heat extraction and release amount may be diverted to the bypass pipe 23 and the third return pipe 21c. With this configuration, by controlling the flow rate of the heat medium to the bypass pipe 23 and the third return pipe 21c using the first regulating valve 41 and the second regulating valve 42, the total amount of heat collected and released from the multiple geothermal heat pumps 10 can be directly recovered within the system. Therefore, even if multiple geothermal heat pumps 10 are installed distributed across multiple buildings, such as in the case of a large-scale geothermal heat recovery heat pump system 1, 100A, 100B, 100C, highly efficient operation can be achieved without the need to measure the amount of heat collected and released from each geothermal heat pump 10. This allows for an efficient operation method for a geothermal heat recovery heat pump system regardless of the system size.

[0060] In the control process, the flow rate of the heat medium with the greater amount of heat extraction and release into the bypass pipe 23 may be adjusted so that the temperature of the heat medium at the point where the bypass pipe 23 joins the supply pipes 22, 122 is equal to the temperature of the heat medium entering the supply pipes 22, 122 from the geothermal heat source 30. With this configuration, the temperature of the heat medium passing through the bypass pipe 23 can be made approximately equal to the temperature of the heat medium at the inlet of the confluence. This means that a portion of the heat radiation generated on the return pipes 21a and 121a side, equal to the heat collected on the return pipes 21b and 121b side, is mutually recovered. Therefore, only the remaining heat radiation generated on the return pipes 21a and 121a side, minus the heat collected on the return pipes 21b and 121b side, is sent to the return pipes 21c and 121c and heat exchanged in the geothermal heat source 30. This reduces the volume of the geothermal heat source 30, i.e., the number of geothermal heat exchangers (GHEX) 30A and the pumping rate of the well equipment 30B. This allows for significant cost reductions regardless of the system size. Furthermore, if the reduction in volume of the geothermal heat source 30 is limited to a certain extent, the change in the underground temperature, which is the heat source, can be mitigated, resulting in a geothermal heat recovery heat pump system 1, 100A, 100B, 100C that can operate more efficiently regardless of the size of the system.

[0061] The geothermal heat recovery heat pump system 1 of the present disclosure includes a geothermal heat recovery heat source network 150 that collects and releases heat, and a plurality of geothermal heat pumps 10 that perform heat load processing by circulating a heat medium between the geothermal heat recovery heat source network 150. The geothermal heat recovery heat pump system 1 includes a first regulating valve 41 and a second regulating valve 42 that can adjust the flow rate of the heat medium passing through the first regulating valve 41, and a valve that controls the flow rate of the heated heat medium from the plurality of geothermal heat pumps 10 to the first regulating valve 41. The system is equipped with a first return pipe 21a, a second return pipe 21b through which the cooled heat transfer medium moves from the multiple geothermal heat pumps 10 to the second regulating valve 42, an outgoing pipe 22 through which the heat transfer medium moves from the geothermal heat recovery heat source network 150 to the multiple geothermal heat pumps 10, a third return pipe 21c through which the heat transfer medium moves from the first regulating valve 41 and the second regulating valve 42 to the geothermal heat recovery heat source network 150, and a bypass pipe 23 through which the heat transfer medium moves from the first regulating valve 41 and the second regulating valve 42 to the outgoing pipe 22.

[0062] The geothermal heat recovery heat pump system 100C of the present disclosure is a geothermal heat recovery heat pump system 100C that includes a geothermal heat source 30 that collects and releases heat, and a geothermal heat pump group having a plurality of geothermal heat pumps 10 that perform heat load processing by circulating a heat medium between the geothermal heat source 30 and the geothermal heat pump group. The geothermal heat recovery heat pump system 100C includes a first regulating valve 41 and a second regulating valve 42 that can adjust the flow rate of the heat medium passing through the geothermal heat pump group having the plurality of geothermal heat pumps 10, and a valve that controls the flow rate of the heated heat medium to be transferred from the geothermal heat pump group having the plurality of geothermal heat pumps 10 to the first regulating valve 41. the first return pipe 21a moving through the ground source heat pump group having a plurality of geothermal heat pumps 10, the second return pipe 21b through which the cooled heat medium moves from the geothermal heat pump group having a plurality of geothermal heat pumps 10 to the second regulating valve 42, the supply pipe 22 through which the heat medium moves from the geothermal heat source 30 to the geothermal heat pump group having a plurality of geothermal heat pumps 10, the third return pipe 21c through which the heat medium moves from the first regulating valve 41 and the second regulating valve 42 to the geothermal heat source 30, and the bypass pipe 23 through which the heat medium moves from the first regulating valve 41 and the second regulating valve 42 to the supply pipe 22.

[0063] The geothermal heat source 30 may also include a plurality of geothermal heat sources 30 installed in a distributed manner. The distributed geothermal heat sources 30 may be individual geothermal heat sources 34 installed individually in a building or on a site where an HP group 141 having a plurality of geothermal heat pumps for heat load treatment is installed. The system may be configured to be expandable in scale by adding more geothermal heat sources 30 installed centrally or in a distributed manner in response to an increase in the number of HP groups 141. When a combined geothermal heat recovery heat pump system 100C having HP groups 141 is connected to a geothermal heat recovery heat source network 150, as regional (area-wide) use of geothermal heat pump systems progresses, it is conceivable that new buildings constructed in the area will also be incorporated into the combined geothermal heat recovery heat pump system 100C. Even if the number of HP groups 141 newly connected to the geothermal heat recovery heat pump system 1 having HP groups increases, the combined heat pump system 100C can be expanded without a shortage of geothermal heat source capacity by installing additional individual geothermal heat sources 34 and connecting them to the geothermal heat recovery heat source network 150.

[0064] Although one embodiment of the present disclosure has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and configuration changes, combinations, deletions, etc. are also included within the scope that does not deviate from the gist of the present disclosure.

[0065] For example, thermometers may be provided on the inlet and outlet sides of each GSHP 10 and on the inlet and outlet sides of the auxiliary heat source. For example, the number and types of GSHPs 10 included in the heat pump system 1 and the number and types of HP groups included in the combined heat pump systems 100A, 100B, and 100C are not limited. For example, an auxiliary heat source may not be included, and only one of an auxiliary heating heat source or an auxiliary cooling heat source may be included. [Explanation of symbols]

[0066] 1, 100A, 100B, 100C Geothermal Heat Recovery Heat Pump System 10. Geothermal Heat Pump (GSHP) 10A Cooling and heating switching type geothermal heat pump (cooling and heating switching GSHP) 10B Cold-only geothermal heat pump (Cold-only GSHP) 10C Heat-only geothermal heat pump (heat-only GSHP) 11, 60 Switching valve 11a First switching valve 11b Second switching valve 20 Piping system 21a, 121a 1st return tube 21b, 121b Second return tube 21c, 121c 3rd return tube 21d Return tube 22, 22b, 22c, 122 Outlet pipe 23 Bypass pipe 30 Geothermal heat source 30A geothermal heat exchanger (GHEX) 30B Well water equipment 31 Pumping well 31a Water pump 32 Reinjection well 33 Common ground heat source 34 Individual geothermal sources 40 Regulating valve 41, 41a, 41b First adjusting valve 42, 42a, 42b Second regulating valve 50 Auxiliary heat source 51 Cooling auxiliary heat source 52 Heating auxiliary heat source 61 First branch return pipe 62 Second branch return pipe 140 Buildings 141 HP group 150 Geothermal Heat Recovery Heat Source Network 200 Heat Pump System 221 Return pipe 222, 222b Outbound pipe T, Ts, Tg, Tb temperature sensors T1 First temperature sensor T2 Second temperature sensor M flow sensor M1 First flow sensor M2 Second flow sensor

Claims

1. A geothermal heat recovery heat pump system comprising a geothermal heat source that extracts and releases heat, and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source and the geothermal heat pump, a first adjusting valve and a second adjusting valve capable of adjusting the flow rate of the heat medium passing through; a first return pipe through which a heated heat medium flows from the plurality of geothermal heat pumps to the first regulating valve; a second return pipe through which the cooled heat medium flows from the plurality of geothermal heat pumps to the second regulating valve; an outgoing pipe through which a heat transfer medium flows from the geothermal heat source to the plurality of geothermal heat pumps; a third return pipe through which a heat medium flows from the first regulating valve and the second regulating valve to the underground heat source; a bypass pipe through which the heat medium flows from the first regulating valve and the second regulating valve to the outflow pipe; A geothermal heat recovery heat pump system equipped with a

2. Among the first regulating valve and the second regulating valve, The adjusting valve through which the heat medium with the smaller heat extraction / radiation amount passes is controlled to suppress the flow rate to the third return pipe and to allow the heat medium to flow to the bypass pipe, 2. The geothermal heat recovery heat pump system of claim 1, wherein the regulating valve through which the heat medium with the greater amount of heat extraction and release passes adjusts the flow rate of the heat medium into the bypass pipe so that the temperature of the heat medium at the point where the bypass pipe joins the supply pipe is controlled to be equivalent to the temperature of the heat medium entering the supply pipe from the geothermal heat source.

3. The geothermal heat recovery system according to claim 1 , wherein the first regulating valve and the second regulating valve are proportional regulating valves.

4. A geothermal heat recovery heat pump system comprising a geothermal heat source that extracts and releases heat, and a plurality of geothermal heat pumps that perform heat load treatment by circulating a heat medium between the geothermal heat source and the geothermal heat pump, an adjusting mechanism for adjusting the flow rate of the heat transfer medium passing through; a first return pipe through which a heated heat medium flows from the plurality of geothermal heat pumps to the adjustment mechanism; a second return pipe through which the cooled heat medium flows from the plurality of geothermal heat pumps to the adjustment mechanism; an outgoing pipe through which a heat transfer medium flows from the geothermal heat source to the plurality of geothermal heat pumps; a third return pipe through which the heat medium flows from the adjustment mechanism to the underground heat source; a bypass pipe through which the heat transfer medium flows from the adjustment mechanism to the outgoing pipe; Equipped with Geothermal heat recovery heat pump system.

5. The geothermal source is soil. The geothermal heat recovery heat pump system according to any one of claims 1 to 4.

6. The geothermal source is well water. The geothermal heat recovery heat pump system according to any one of claims 1 to 4.

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

8. The auxiliary heat source is a cooling auxiliary heat source connected to the third return pipe and assisting the geothermal heat pump in treating the heat load of a load target.

8. The geothermal heat recovery heat pump system according to claim 7.

9. The auxiliary heat source is connected to the supply pipe between the geothermal heat source and a portion where the supply pipe and the bypass pipe join, and is an auxiliary heating heat source that assists the geothermal heat pump in treating the heat load of a load target.

8. The geothermal heat recovery heat pump system according to claim 7.

10. The plurality of geothermal heat pumps include a geothermal heat pump that can be switched between cold and hot operation, a first switching valve is disposed between the cold / hot switching geothermal heat pump and the first return pipe; A second switching valve is disposed between the cold / hot switching geothermal heat pump and the second return pipe. The geothermal heat recovery heat pump system according to any one of claims 1 to 4.

11. At least one of the first regulating valve and the second regulating valve is installed in a building different from a building in which the plurality of geothermal heat pumps are installed. The geothermal heat recovery heat pump system according to claim 1 .

12. Further provided is a first temperature sensor that measures the temperature of the heat medium on the inlet side of the first regulating valve, and a second temperature sensor that measures the temperature of the heat medium on the inlet side of the second regulating valve. The geothermal heat recovery heat pump system according to claim 1 .

13. 2. A method for operating a geothermal heat recovery heat pump system according to claim 1, comprising: a control step of controlling the first regulating valve and the second regulating valve based on a comparison result between a heat collection amount of the heat medium passing through the first return pipe and a heat release amount of the heat medium passing through the second return pipe; In the control step, the heat medium with a smaller amount of heat extraction and release is controlled to flow into the bypass pipe, and the heat medium with a larger amount of heat extraction and release is controlled to flow into the bypass pipe and the third return pipe. A method for operating a geothermal heat recovery heat pump system.

14. In the control step, the flow rate of the heat medium with a larger amount of heat extraction and release into the bypass pipe is adjusted so that the temperature of the heat medium at the portion where the bypass pipe joins the outflow pipe is equal to the temperature of the heat medium entering the outflow pipe from the geothermal heat source. A method for operating a geothermal heat recovery heat pump system according to claim 13.

15. A geothermal heat recovery heat pump system comprising: a geothermal heat recovery heat source network that collects and releases heat; and a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat recovery heat source network, a first adjusting valve and a second adjusting valve capable of adjusting the flow rate of the heat medium passing through; a first return pipe through which a heated heat medium flows from the plurality of geothermal heat pumps to the first regulating valve; a second return pipe through which the cooled heat medium flows from the plurality of geothermal heat pumps to the second regulating valve; an outgoing pipe through which a heat medium flows from the geothermal heat recovery heat source network to the plurality of geothermal heat pumps; a third return pipe through which a heat medium flows from the first regulating valve and the second regulating valve to the geothermal heat recovery heat source network; a bypass pipe through which the heat medium flows from the first regulating valve and the second regulating valve to the outflow pipe; A geothermal heat recovery heat pump system equipped with a

16. A geothermal heat recovery heat pump system comprising: a geothermal heat source that extracts and releases heat; and a geothermal heat pump group having a plurality of geothermal heat pumps that perform heat load processing by circulating a heat medium between the geothermal heat source and the geothermal heat pump; a first adjusting valve and a second adjusting valve capable of adjusting the flow rate of the heat medium passing through; a first return pipe through which a heated heat medium flows from the geothermal heat pump group including the plurality of geothermal heat pumps to the first regulating valve; a second return pipe through which the cooled heat medium flows from the geothermal heat pump group including the plurality of geothermal heat pumps to the second regulating valve; an outgoing pipe through which a heat medium flows from the geothermal heat source to the geothermal heat pump group including the plurality of geothermal heat pumps; a third return pipe through which a heat medium flows from the first regulating valve and the second regulating valve to the underground heat source; a bypass pipe through which the heat medium flows from the first regulating valve and the second regulating valve to the outflow pipe; A geothermal heat recovery heat pump system equipped with a

17. The geothermal heat source has a plurality of geothermal heat sources installed in a dispersed manner.

17. The geothermal heat recovery heat pump system of claim 16.

18. The distributed geothermal heat sources are individual geothermal heat sources installed individually in the buildings or on the premises where the geothermal heat pump group that performs heat load treatment is installed.

17. The geothermal heat recovery heat pump system of claim 16.

19. The system is configured so that the scale can be expanded by adding more geothermal heat sources, either centrally or distributed, in response to an increase in the number of geothermal heat pumps.

17. The geothermal heat recovery heat pump system of claim 16.

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