JP2007051579A - Cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cogeneration system of high energy efficiency by preventing the shortage of hot water supply capacity in winter time and surplus of hot water in summer time as much as possible without enlarging the capacity of a cogeneration device. <P>SOLUTION: The cogeneration system is provided with a power generating device 11, a hot water storage tank 15, and an electric air conditioning device 50 constructed to exchange heat between refrigerant circulated inside and hot water in the hot water storage tank 15. The power generating device 11 is controlled to maintain fixed output electric power established according to electric power consumed by a load apparatus. When thermal energy of hot water used by hot water using apparatuses 20a, 20b can not be covered by only thermal energy from the power generating device 11, the electric air conditioning device 50 is operated to replenish the same with thermal energy from the electric air conditioning device 50. When thermal energy from the power generating device 11 is more than thermal energy of hot water used by the hot water using apparatuses 20a, 20b, the electric air conditioning device 50 is operated to use surplus thermal energy to heat refrigerant of the electric air conditioning device 50. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cogeneration system.

As this cogeneration system, as shown in Patent Document 1, a cogeneration apparatus 10 that outputs fuel and electric power and heat is supplied, and the heat generated by the cogeneration apparatus 10 is used for processing. What is provided with the air conditioner 20 which supplies the air which was performed indoors, and the hot water supply apparatus 40 which supplies the hot water produced | generated by the warm heat which the said cogeneration apparatus 10 outputs to the utilization side is known.
JP 2003-227628 A

  On the other hand, the following points are clear from the monthly energy consumption statistics of general detached houses in Japan. When comparing hot water supply in summer and winter, for example, the amount of hot water supply in February is about three times that in August. Further, if hot water is supplied using hot water in the hot water storage tank 41 of the hot water supply apparatus 40, the hot water supply amount in February is about five times that in August. On the other hand, the amount of electricity is less likely to fluctuate annually than the amount of hot water supply, and is stable at 250 to 350 Mcal. As described above, when the fluctuation of hot water supply is large between summer and winter and the fluctuation of electricity is small, there is a problem that the hot water supply is insufficient in winter and the hot water is surplus in summer.

  In order to solve this, it is conceivable that the capacity of the cogeneration device 10 is increased to increase the amount of hot water supply. However, there is a problem that increasing the capacity reduces energy efficiency and increases costs.

  The present invention has been made to solve the above-mentioned problems, and without increasing the capacity of the cogeneration apparatus, prevents a shortage of hot water supply in the winter and a surplus of hot water in the summer as much as possible to achieve high energy efficiency cogeneration. The purpose is to provide a system.

  In order to solve the above problems, the structural feature of the invention according to claim 1 is that a power generation device, a storage battery that stores electric energy from the power generation device, and thermal energy generated by power generation of the power generation device are recovered. A hot water storage tank for storing the hot water and supplying the hot water stored in the hot water supply equipment that uses the hot water, cooling or heating the air-conditioning target space, and circulating refrigerant and hot water in the hot water storage tank. An electric air conditioner configured to exchange heat between the power generation device, a power generation control means for controlling the power generation device so as to have a constant output power set according to the power consumption of the load device, and the output power from the power consumption If there are many, the storage control means for storing the surplus electrical energy in the storage battery, and the thermal energy of hot water used in hot water use equipment only by the thermal energy from the power generator If not, heat energy supplement control means that operates the electric air conditioner and replenishes it with the heat energy from the electric air conditioner, and the heat energy from the power generator generates heat from the hot water used in the hot water use equipment. In the case where the energy is higher than the energy, a heat energy utilization control means is provided for operating the electric air conditioner and utilizing the remaining heat energy for heating the refrigerant of the electric air conditioner.

  A structural feature of the invention according to claim 2 is that, in claim 1, the constant output power is set in a range in which the power generator operates with high efficiency.

  Further, the structural feature of the invention according to claim 3 is that in claim 1, the constant output power depends on the power consumption of the load device from a plurality of set values set in a range in which the power generator operates with high efficiency. Are automatically selected.

  According to a fourth aspect of the present invention, there is provided a configurational feature of the electric heating apparatus according to the first aspect, wherein the electric heating device is provided between the hot water storage tank and the hot water use device and heats the hot water in the hot water storage tank and supplies the hot water Is further provided.

  The structural feature of the invention according to claim 5 is the structural feature of claim 1, further comprising an electric desiccant air conditioner that uses an adsorbent to adjust the humidity of the air-conditioning target space. It is to regenerate by the heat energy of the air conditioner.

  In the invention according to claim 1 configured as described above, the power generation control unit controls the power generation device so as to obtain a constant output power set according to the power consumption of the load device. Since the power generation device is operated with a constant output power without causing the output power to follow the power consumption of the load device, the power generation device can be operated with high energy efficiency. Further, when the power storage control means has a larger output power than the power consumption, the remaining electrical energy is stored in the storage battery, so that the electrical energy can be used without waste.

  Furthermore, when the thermal energy supplement control means cannot cover the thermal energy of the hot water used in the hot water use equipment only by the thermal energy from the power generator, the electric air conditioner is operated to Refill with thermal energy. In other words, if the exhaust heat of the power generator operating at a constant output power cannot cover the thermal energy of hot water used in hot water use equipment, it is stored in the storage battery, for example, electric energy surplus in power generation It can be replenished with thermal energy from an electric air conditioner that can be operated using electrical energy. Therefore, the energy (thermal energy and electric energy) generated by the operation of the power generation apparatus can be used effectively, and a shortage of hot water can be prevented as much as possible.

  Furthermore, when the thermal energy utilization control means has more thermal energy from the power generator than hot water used in hot water utilization equipment, the electric air conditioner is operated and the remaining thermal energy is removed from the electric air conditioning. It is used for heating the refrigerant of the device. That is, when the exhaust heat of the power generator operating at a constant output power is surplus, the surplus heat energy can be used for heating the refrigerant of the electric air conditioner. Therefore, the energy (thermal energy and electric energy) generated by the operation of the power generator can be used effectively, and excess hot water can be prevented as much as possible.

  In the invention according to claim 2 configured as described above, in the invention according to claim 1, the constant output power is set in a range in which the power generator operates with high efficiency. Since the power is driven with a constant output power within the range of the high-efficiency operation without following the power consumption of the load device, it is possible to operate with high efficiency.

  In the invention according to claim 3 configured as described above, in the invention according to claim 1, the constant output power is obtained from a plurality of set values set in a range in which the power generator operates with high efficiency. Since the power generator is automatically selected according to the power consumption, the power generator does not cause the output power to continuously follow the power consumption of the load device, and the output power is constant according to the power consumption within the range of high-efficiency operation. Therefore, it is possible to drive with high efficiency and appropriateness.

  In the invention according to claim 4 configured as described above, in the invention according to claim 1, the hot water in the hot water storage tank is provided between the hot water storage tank and the hot water use device and is supplied to the hot water use device. Since the electric heating device is further provided, when the output power is larger than the power consumption, the surplus electric energy is used in the electric heating device, so that the electric energy can be used without waste.

  The invention according to claim 5 configured as described above further includes an electric desiccant air conditioner that adjusts the humidity of the air-conditioning target space using the adsorbent in the invention according to claim 1, and generates the adsorbent as power generation. Since the heat energy from the power generator or electric air conditioner is surplus, the surplus heat energy is used by the electric desiccant air conditioner. It can be used without waste, and the shortage of hot water can be prevented as much as possible.

  Hereinafter, an embodiment of a cogeneration system according to the present invention will be described. FIG. 1 is a schematic diagram showing an overview of this cogeneration system. This cogeneration system is generated in accordance with the power generation of the power generation device 11, the inverter 12 that supplies electric energy from the power generation device 11 to the load device 21 and stores it in the storage battery 13, and the power generation device 11. A hot water storage tank 15 is provided that stores hot water from which thermal energy has been collected and supplies the stored hot water to hot water use devices 20a and 20b that use the hot water.

  The power generation device 11 generates power and supplies the power to a load device 21 such as an electric device. For example, a fuel cell power generation device, a diesel engine, a gas engine, a gasoline engine, a gas turbine, a micro gas turbine, or the like. An engine power generator using an engine as a drive source can be mentioned. In the present embodiment, an engine power generator will be described as an example. This power generator 11 is supplied with fuel, for example, natural gas, and burns this fuel to drive the engine. The power generation device 11 is connected to the control device 70 and is controlled according to a command from the control device 70.

  A power generator 11 is connected to the inverter 12. When the power generation device 11 is a DC power generation device such as a fuel cell power generation device, the inverter 12 converts DC power into AC power and supplies it to the load device 21. When the power generation device 11 is an AC power generation device such as an engine power generation device, the inverter 12 changes from AC power to DC power, and then converts DC power to AC power and supplies it to the load device 21. When the power generation device 11 is a DC power generation device, the storage battery 13 is connected to DC power from the power generation device 11, and when the power generation device 11 is an AC power generation device, the storage battery 13 is converted to DC power converted by the inverter 12. It is connected. FIG. 1 shows a case where the power generator 11 is an AC power generator. The storage battery 13 has a charge / discharge control function. The DC power from the storage battery 13 is converted into AC power by the inverter 12 and supplied to the load device 21. The system power supply 14 is connected so as to merge with AC power output from the inverter 12.

  The inverter 12 is connected not only to the load device 21 but also to the electric water heater 17, the electric air conditioner 50, and the electric desiccant air conditioner 60 that are electric devices constituting the cogeneration system. The inverter 12 is connected to the control device 70 and is controlled according to a command from the control device 70. Moreover, the wattmeter 12a is provided in the point where the alternating current power output from the system power supply 14 and the inverter 12 merges. The wattmeter 12 a detects the total power consumption of all the load devices 21, the electric water heater 17, the electric air conditioner 50, the electric desiccant air conditioner 60, etc., and transmits it to the control device 70. Yes.

  Further, the power generation device 11 is connected to a cooling circuit 31 in which a first heat medium that recovers exhaust heat of the power generation device 11 and cools the power generation device 11 circulates. On the cooling circuit 31, the 1st heat exchanger 41 and the 1st pump P1 are arrange | positioned. The first pump P1 is driven and controlled in accordance with a command from the control device 70 to circulate the first heat medium. Thus, when the first pump P1 is driven while the power generation device 11 is generating power, the first heat medium that has recovered the exhaust heat of the power generation device 11 is cooled through the first heat exchanger 41 and is again generated. To come back. For example, in the case of a fuel cell power generation device, the exhaust heat of the power generation device 11 refers to exhaust heat of a fuel cell stack or exhaust heat of a reformer, and in the case of an engine power generation device, examples include exhaust heat of an engine. However, the present invention is not limited to this, and any recoverable exhaust heat such as heat of the generator itself can be used.

  The hot water storage tank 15 includes one columnar container, and hot water is stored in a layered manner inside the hot water tank 15, that is, the hot water in the upper part is the hottest and the temperature is lowered as it goes to the lower part, and the hot water in the lower part is coldest. It has become so. Hot water stored in the hot water storage tank 15 is led out from the upper part of the columnar container of the hot water storage tank 15, and water is supplied from the lower part of the columnar container of the hot water storage tank 15 through the water supply port 15a so as to replenish the derived amount. Water such as water (low-temperature water) has been introduced.

  Further, inside the hot water storage tank 15, a temperature sensor group T1 that is a remaining hot water amount detection sensor is provided. The temperature sensor group T1 includes a plurality of (in this embodiment, five) temperature sensors T1-1, T1-2, T1-3,..., T1-5, and is arranged in the vertical direction (vertical direction). Are arranged at equal intervals (distance of a quarter of the vertical height in the hot water storage tank 15). The temperature sensor T <b> 1-1 is disposed at the upper surface position inside the hot water storage tank 15. Each of the temperature sensors T1-1, T1-2, T1-3,..., T1-5 detects the temperature of the liquid (hot water or water) in the hot water storage tank 15 at that position. The amount of hot water in the hot water storage tank 15 is detected based on the detection result of the hot water temperature at each position by the temperature sensor group. The remaining hot water amount represents the remaining amount of hot water remaining in the hot water storage tank 15 that is equal to or higher than a predetermined temperature (for example, 60 ° C.). Therefore, for example, when each temperature sensor T1-1 to T1-3 detects 60 ° C. or more and each temperature sensor T1-4 and T1-5 detects less than 60 ° C., the remaining hot water amount detection sensor T1 Detects the water amount (hot water amount) from the ceiling inner wall surface of the hot water storage tank 15 to the temperature sensor T1-3 as the remaining hot water amount. The amount of remaining hot water at this time is ½ of the capacity of the hot water storage tank 15. When each temperature sensor T1-1 to T1-4 detects 60 ° C. or more and each temperature sensor T1-5 detects less than 60 ° C., the remaining hot water amount detection sensor T1 is a capacity of the hot water storage tank 15. 3/4 is detected as the amount of remaining hot water.

  The amount of remaining hot water between the temperature sensor detecting 60 ° C. or more and the temperature sensor detecting less than 60 ° C. is based on the temperature gradient calculated by a plurality of upper and lower temperature sensors including these two temperature sensors and the distance between the sensors. Therefore, the amount of remaining hot water in the hot water storage tank 15 can be calculated more accurately by adding the calculated amount of remaining hot water between the sensors.

  The hot water storage tank 15 is connected to a hot water circulation circuit 32 for heating the hot water in the hot water storage tank 15. On the hot water circulation circuit 32, the 2nd heat exchanger 42, the 1st heat exchanger 41, and the 2nd pump P2 are arrange | positioned. The first heat exchanger 41 performs heat exchange between the first heat medium circulating in the cooling circuit 31 and the hot water circulating in the hot water circulation circuit 32. The second heat exchanger 42 performs heat exchange between the second heat medium circulating in the heat medium circulation circuit 33 and hot water circulating in the hot water circulation circuit 32. The second pump P2 is driven and controlled according to a command from the control device 70 to circulate hot water.

  A hot water supply pipe 34 is connected to the hot water storage tank 15. In the hot water supply pipe 34, an electric water heater 16, a temperature sensor T2, and a flow rate sensor 17, which are electric heating devices, are arranged in order from the upstream. The electric water heater 16 heats hot water from the hot water storage tank 15 passing through the hot water supply pipe 34 to supply hot water. The temperature sensor T <b> 2 detects the temperature of the hot water after passing through the electric water heater 16, and the detection signal is transmitted to the control device 70. That is, the electric water heater 16 is heated so that the temperature of the hot water detected by the temperature sensor T2 becomes the set hot water supply temperature. Although not shown, tap water from the water supply port 15a joins the hot water supply pipe 34 between the outlet port of the hot water storage tank 15 and the temperature sensor T2. Thereby, the temperature of the hot water from the hot water storage tank 15 is lowered. The flow rate sensor 17 detects the amount of hot water supplied from the hot water storage tank 15. A detection signal of the flow sensor 17 is transmitted to the control device 70.

  The hot water supply pipe 34 is connected to a plurality of hot water use devices 20a that use hot water stored in the hot water storage tank 15 as hot water supply. Examples of the hot water use device 20a include a bathtub, shower, kitchen (kitchen faucet), and washroom (toilet faucet). The hot water supply pipe 34 is connected to a heat utilization device 20b that uses hot water in the hot water storage tank 15 as a heat source. Examples of the heat utilization device 20b include bathroom heating, floor heating, and a mechanism for cooking hot water from a bathtub. The heat utilization device 20b may use the hot water in the hot water storage tank 15 directly or may indirectly use the hot water in the hot water storage tank 15. The hot water utilization device 20a and the heat utilization device 20b are both hot water utilization devices. Furthermore, an electric desiccant air conditioner 60 is connected to the hot water supply pipe 34, and the thermal energy of the hot water in the hot water storage tank 15 is used as a heat source for regenerating the adsorbent of the rotary dehumidifier 63 described later. .

  Further, the cogeneration system includes an electric air conditioner 50. The electric air conditioner 50 is of a type in which a compressor (compressor) 52 is driven by an electric motor 51. The electric air conditioner 50 is configured to cool or heat the air-conditioning target space and exchange heat between the refrigerant circulating inside and the hot water in the hot water storage tank 15. The electric air conditioner 50 includes an outdoor unit 50a and an indoor unit 50b as mainly shown in FIG. The outdoor unit 50a and the indoor unit 50b are connected via a refrigerant circuit 50c in which the refrigerant circulates.

  The outdoor unit 50 a includes an electric motor 51, a compressor 52 driven by the electric motor 51, a four-way valve 53, an outdoor heat exchanger 54, an outdoor expansion valve 55, and a third heat exchanger 43. The four-way valve 53 switches the refrigerant flow between the heating operation and the refrigerant operation according to a command from the control device 70. The outdoor heat exchanger 54 performs heat exchange between the refrigerant and the outside air. The outdoor heat exchanger 54 includes a blower 54 a that is controlled by a command from the control device 70. The outdoor expansion valve 55 is controlled to open and close according to a command from the control device 70, and is a valve for expanding the compressed gaseous refrigerant to a low temperature. The third heat exchanger 43 performs heat exchange between the refrigerant circulating in the refrigerant circuit 50 c and the second heat medium circulating in the heat medium circulation circuit 33. A second heat exchanger 42 and a third pump P3 are disposed on the heat medium circuit 33. The third pump P3 is driven and controlled according to a command from the control device 70 to circulate the second heat medium.

  The indoor unit 50b includes an indoor expansion valve 56 and an indoor heat exchanger 57. The indoor expansion valve 56 is controlled to open and close according to a command from the control device 70, and is a valve for expanding the compressed gaseous refrigerant to a low temperature. The indoor heat exchanger 57 performs heat exchange between the refrigerant and the air in the room where the indoor unit 50b, which is the air-conditioning target space, is installed. The indoor heat exchanger 57 includes a blower 57 a that is controlled by a command from the control device 70. A plurality of indoor units 50b may be connected to one outdoor unit 50a.

  The operation of the electric air conditioner 50 configured as described above will be described. During the heating operation, the four-way valve 53 is switched to the state shown by the solid line in FIG. 2, and the compressor 52 is driven by the operation of the electric motor 51. The refrigerant evaporated and absorbed by the outdoor heat exchanger 54 to become a low-temperature / low-pressure gas is compressed by the compressor 52 to become a high-temperature / high-pressure gas. Thereafter, the refrigerant is condensed in the indoor heat exchanger 57 to become a high-temperature and high-pressure liquid, and releases heat when liquefied. At this time, the air blown by the blower 57a becomes warm air to heat the room. Then, the refrigerant passes through the indoor expansion valve 56 controlled to be throttled to become a low-temperature / low-pressure liquid, passes through the outdoor expansion valve 55 in the open state, and then returns to the outdoor heat exchanger 54. This process is repeated.

  At this time, if the third pump P3 provided on the heat medium circulation circuit 33 is driven, the third heat exchanger 43 further heats the refrigerant that is a high-temperature and high-pressure gas compressed by the compressor 52. In addition, the heating capacity of the electric air conditioner 50 can be improved.

  On the other hand, during the cooling operation, the four-way valve 53 is switched to the state indicated by the broken line in FIG. 2, and the compressor 52 is driven by the operation of the electric motor 51. The refrigerant sent in the low-temperature / low-pressure liquid evaporates in the indoor heat exchanger 57 to become a low-temperature / low-pressure gas, but at this time, it takes heat from the indoor air. If it blows here with the air blower 57a, it becomes a cold wind and can be cooled. The refrigerant that has become a low-temperature and low-pressure gas is then compressed by the compressor 52 to become a high-temperature and high-pressure gas. Then, in the outdoor heat exchanger 54, the refrigerant is condensed by the outside air and releases heat to become a high-temperature / high-pressure liquid. Then, the refrigerant expands through the outdoor expansion valve 55 to become a low-temperature and low-pressure liquid, passes through the open indoor expansion valve 56, and then returns to the indoor heat exchanger 57. This process is repeated.

  At this time, when the third pump P3 provided on the heat medium circulation circuit 33 is driven, the refrigerant that is evaporated in the third heat exchanger 43 by the indoor heat exchanger 57 and becomes a low-temperature / low-pressure gas. And a second heat medium circulating in the heat medium circuit 33 are exchanged. As a result, the heat of the refrigerant of the electric air conditioner 50 is transferred to the second heat medium and is recovered in the hot water in the hot water storage tank 15 via the second heat exchanger 42. For this reason, the energy utilization efficiency of the whole system can be improved. On the other hand, since the refrigerant of the electric air conditioner 50 is cooled by the second heat medium, the cooling capacity of the electric air conditioner 50 can also be improved.

  The cogeneration system also includes an electric desiccant air conditioner 60 that adjusts the humidity of the air-conditioned space using an adsorbent. The electric desiccant air conditioner 60 includes an air supply passage 61 that introduces outside air into the room and an exhaust passage 62 that exhausts room air. The air supply passage 61 and the exhaust passage 62 are disposed adjacent to each other. In the air supply passage 61, one half of the rotary dehumidifier 63 and one half of the rotary sensible heat exchanger 64 are sequentially arranged from the outdoor side toward the indoor side. On the other hand, the other half of the rotary dehumidifier 63, the regeneration heater 65, the other half of the rotary sensible heat exchanger 64, and the exhaust fan 66 are sequentially arranged in the exhaust passage 62.

  The rotary dehumidifier 63 is a rotary rotor in which a honeycomb-like air passage is formed by a sheet-like material impregnated and synthesized with silica gel using a glass fiber as a base material. The rotary dehumidifier 63 is disposed across the adjacent air supply passage 61 and the exhaust passage 62 so as to adsorb and dehumidify the water vapor in the air supply passing through one half of the air supply passage 61. In the other half of the exhaust passage 62, the adsorbent is dehumidified and regenerated by the heated hot indoor exhaust that passes therethrough.

  The rotary sensible heat exchanger 64 is a rotary rotor in which a honeycomb-shaped air passage is formed by an aluminum plate. The rotary sensible heat exchanger 64 passes through one half of the air supply passage 61 and the other half of the exhaust passage 62 through an aluminum plate forming a honeycomb-like air passage. The sensible heat is exchanged with the indoor exhaust.

  The regenerative heater 65 is a regenerative heater that dehumidifies and regenerates the adsorbent by heating indoor exhaust using hot water in the hot water storage tank 15 supplied from the hot water supply pipe 34 as a heat source. The room exhaust heated by the other half of the exchanger 64 is further heated. P4 represents a hot water supply pump. Further, the regeneration heater 65 may use the heat energy of the electric air conditioner 50 as a heat source via a heat medium circulation circuit.

  The power generator 11, the inverter 12, the power meter 12a, the storage battery 13, the temperature sensor group T1 of the hot water storage tank 15, the electric water heater 6, the flow sensor 17, the temperature sensor T2, the pumps P1 to P4, the electric motor 51, and the four-way valve 53. The blower 54a, the outdoor expansion valve 55, the indoor expansion valve 56, the blower 57a, the rotary dehumidifier 63, the rotary sensible heat exchanger 64, and the exhaust fan 66 are connected to the control device 70 as shown in FIG. Has been. The control device 70 includes a microcomputer (not shown), and the microcomputer includes an input / output interface, a CPU, a RAM, and a ROM (all not shown) connected via a bus. The CPU controls the operation of the above-described cogeneration system. The RAM temporarily stores variables necessary for executing a control program for controlling the operation of the system, and the ROM stores the control program.

  Next, the operation of the above-described cogeneration system will be described with reference to the flowcharts of FIGS. When a main switch (not shown) is turned on, the control device 70 starts the program at step 100 and repeatedly executes it at predetermined short intervals. The control device 70 measures the total power consumption of the load device 21 by the wattmeter 12a (step 102). Then, based on the measurement result, the power generation device 11 is controlled to have a constant output power within the high efficiency region (power generation control means: step 104). Specifically, the control device 70 sets constant output power according to the power consumption of the load device 21. This constant output power may be set based on the amount of electricity of the monthly energy shown above, for example. This constant output power is preferably set in a range in which the power generator 11 operates with high efficiency. That is, it is an output range in which the power generator 11 can be operated with high efficiency (for example, within 70 to 100% of the rated output). The constant output power may be automatically selected according to the power consumption of the load device 21 from a plurality of set values set in a range in which the power generation apparatus 11 operates with high efficiency.

  The control device 70 compares the output power of the power generation device 11 with the power consumption of the load device 21 (step 106). If the output power is insufficient, the control device 70 supplements the power from the system power supply 14 (step 112). . On the other hand, when the output power is surplus, when the storage battery 13 is not fully charged, the inverter 12 is controlled to store the surplus electrical energy in the storage battery 13 (storage control means: step 110). If the storage battery 13 is fully charged, the program proceeds to step 114.

  The control device 70 measures the outside air temperature with the outside air temperature sensor T3 (step 114), and predicts the hot water demand based on the measurement result (step 116). Thereby, the hot water demand according to the season which operates a cogeneration system can be predicted appropriately. Specifically, the season is predicted based on the trend of the outside temperature, the past hot water usage history map of the predicted season is read, and the hot water demand is predicted based on the hot water usage history map.

  In step 118, the control device 70 measures the amount of hot water in the hot water storage tank 15 by the temperature sensor group T1. Then, control device 70 determines whether or not the amount of hot water supply is insufficient based on the previously obtained hot water demand and remaining hot water amount (step 120). Specifically, for example, when the remaining hot water amount is larger than the hot water demand amount within a predetermined time from the present time, it is determined that the hot water supply amount is not insufficient. Moreover, when the remaining hot water amount is smaller than the hot water demand amount, it is determined that the hot water supply amount is insufficient.

  Then, when the thermal energy from the power generator 11 alone cannot cover the thermal energy of the hot water used in the hot water use devices 20a and 20b, the control device 70 operates the electrical air conditioner 50 to perform the electrical air conditioning. Replenishment with thermal energy from the apparatus 50 (thermal energy supplementation control means: step 126). Specifically, the control device 70 determines “YES”, “YES”, or “NO” in steps 120, 122, and 124 and operates both the power generation device 11 and the electric air conditioner 50. In step 126, the electric air conditioner 50 is cooled as described above, and the second and third pumps P2 and P3 are driven. Thus, as described above, the heat of the high-temperature refrigerant is recovered into the hot water through the third heat exchanger 43, the heat medium circulation circuit 33, and the second heat exchanger 42, and the hot water is heated.

  In step 122, it is determined whether or not the power generation apparatus 11 is in operation. In step 124, based on the current power generation status of the power generation device 11 and the past power demand history of the season, the thermal energy of the hot water used in the hot water use devices 20a and 20b is obtained only by the thermal energy associated with the current power generation amount. Determine if you can afford.

  When the power generator 11 is not operated, “YES” and “NO” are determined in steps 120 and 122, and the electric air conditioner 50 is operated alone. At this time, when the thermal energy from the electric air conditioner 50 can cover the thermal energy of the hot water used in the hot water use devices 20a and 20b, it is determined as “YES” in step 132, and the program proceeds to step 128. Exit the program. Further, when the thermal energy from the electric air conditioner 50 is not enough to cover the thermal energy of the hot water used in the hot water utilization devices 20a and 20b, it is determined as “NO” in step 132, and the power is generated in step 134. The apparatus 11 is also operated.

  On the other hand, when the thermal energy from the power generation device 11 is greater than the thermal energy of the hot water used in the hot water use devices 20a and 20b, the electric air conditioner 50 is operated and the remaining heat energy is transferred to the electric air conditioner 50. This is used for heating the refrigerant (thermal energy utilization control means: step 142). Specifically, the control device 70 determines “YES” in steps 120, 136, and 138, and operates both the power generation device 11 and the electric air conditioner 50. In step 142, the electric air conditioner 50 is heated as described above, and the second and third pumps P2 and P3 are driven. Thereby, as described above, the heat of the hot water in the hot water storage tank 14 is recovered into the refrigerant of the refrigerant circuit 50c via the second heat exchanger 42, the heat medium circulation circuit 33, and the third heat exchanger 43, and the refrigerant is As it is heated, the temperature of the hot water drops.

  In step 136, as in step 120, it is determined whether or not there is a remaining hot water supply amount based on the previously obtained hot water demand and remaining hot water amount. Specifically, for example, when the remaining hot water amount is larger than the hot water demand amount within a predetermined time from the present time, it is determined that the hot water supply amount is excessive. Further, when the remaining hot water amount is smaller than the hot water demand amount, it is determined that the hot water supply amount is not excessive. In step 138, it is determined whether or not the electric air conditioner 50 is in operation. If the electric air conditioner 50 is not operated, “NO” is determined in step 138, the operation of the electric air conditioner 50 is started, and the program proceeds to step 142.

  As is apparent from the above description, in this embodiment, the power generation control means (step 104) controls the power generation device 11 so as to have a constant output power set according to the power consumption of the load device 21. . Since the power generation device 11 is operated with a constant output power without causing the output power to follow the power consumption of the load device 21, it can be operated with high energy efficiency. Further, when the power storage control means (step 110) has a larger output power than the power consumption, the remaining electrical energy is stored in the storage battery 13, so that the electrical energy can be used without waste.

  Furthermore, when the thermal energy supplement control means (step 126) cannot cover the thermal energy of the hot water used in the hot water use devices 20a and 20b only by the thermal energy from the power generator 11, the electric air conditioner 50 is switched on. It is operated and replenished with thermal energy from the electric air conditioner 50. That is, if the heat energy of the hot water used in the hot water use devices 20a and 20b cannot be covered by the exhaust heat of the power generation device 11 that is operating at a constant output power, for example, the electric energy remaining in the power generation, the storage battery 13 It can be replenished with thermal energy from the electric air conditioner 50 that can be operated using the electrical energy stored in the battery. Therefore, the energy (thermal energy and electrical energy) generated by the operation of the power generator 11 can be used effectively, and a shortage of hot water can be prevented as much as possible.

  Furthermore, when the thermal energy utilization control means (step 142) has more thermal energy from the power generator 11 than hot water used in the hot water utilization devices 20a and 20b, the electric air conditioner 50 is operated. The surplus heat energy is used for heating the refrigerant of the electric air conditioner 50. That is, when the exhaust heat of the power generation apparatus 11 operating at a constant output power is surplus, the surplus heat energy can be used for heating the refrigerant of the electric air conditioner 50. Therefore, the energy (thermal energy and electrical energy) generated by the operation of the power generation device 11 can be used effectively, and excess hot water can be prevented as much as possible.

  Further, since the constant output power is set in a range in which the power generation device 11 operates with high efficiency, the power generation device 11 can perform high efficiency operation without causing the output power to follow the power consumption of the load device 21. Since it is operated with constant output power within the range, it can be operated with high efficiency.

  Further, the constant output power is automatically selected according to the power consumption of the load device 21 from a plurality of set values set in a range in which the power generation device 11 operates with high efficiency. Since the output power is operated with a constant output power corresponding to the power consumption within the range of the high-efficiency operation without continuously following the power consumption of the load device 21, it is possible to operate with high efficiency and appropriately. .

  In addition, since the electric water heater 16 is provided between the hot water storage tank 15 and the hot water use devices 20a and 20b and is an electric heating device that heats the hot water in the hot water storage tank 15 and supplies the hot water to the hot water use devices 20a and 20b. When the output power is higher than the power consumption, the excess electric energy is used in the electric water heater 16, so that the electric energy can be used without waste.

  Further, the electric desiccant air conditioner 60 that adjusts the humidity of the air-conditioning target space using the adsorbent is further provided, and the adsorbent is regenerated by the thermal energy of the power generator 11 or the electric air conditioner 50. When there is surplus heat energy from the electric air conditioner 50, the surplus heat energy is used in the electric desiccant air conditioner 60, so that the heat energy can be used without waste and to prevent hot water shortage as much as possible. Can do.

It is a schematic diagram showing an outline of one embodiment of a cogeneration system according to the present invention. It is a schematic diagram which shows the outline | summary of the electric air conditioner and electric desiccant air conditioner which are shown in FIG. It is a block diagram which shows the cogeneration system shown in FIG. 4 is a flowchart of a control program executed by the control device shown in FIG. 3. 4 is a flowchart of a control program executed by the control device shown in FIG. 3.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Power generation device, 12 ... Inverter, 12a ... Wattmeter, 13 ... Storage battery, 14 ... System power supply, 15 ... Hot water storage tank, 16 ... Electric water heater, 17 ... Flow rate sensor, 21 ... Load equipment, 20a ... Hot water use equipment, 20b ... Heat utilization equipment, 31 ... Cooling circuit, 32 ... Hot water circulation circuit, 33 ... Heat circulation circuit, 34 ... Hot water supply pipe, 41-43 ... First to third heat exchangers, 50 ... Electric air conditioner, 51 ... Electric motor, 52 ... compressor, 53 ... four-way valve, 54 ... outdoor heat exchanger, 55 ... outdoor expansion valve, 56 ... indoor expansion valve, 57 ... indoor heat exchanger, 60 ... electric desiccant air conditioner, 63 ... rotary type Dehumidifier, 64 ... Rotary sensible heat exchanger, 65 ... Regeneration heater, 70 ... Control device, T1 ... Temperature sensor group, T2 ... Temperature sensor, T3 ... Outside air temperature sensor.

Claims (5)

A power generator,
A storage battery for storing electrical energy from the power generator;
A hot water storage tank for storing hot water recovered from the heat energy generated by the power generation of the power generation device and supplying the stored hot water to a hot water use device using the hot water;
An air conditioner configured to cool or heat the air-conditioning target space and to exchange heat between the refrigerant circulating inside and the hot water in the hot water storage tank;
Power generation control means for controlling the power generation device so as to have a constant output power set according to the power consumption of the load device;
When the output power is greater than the power consumption, power storage control means for storing the excess electrical energy in the storage battery,
When the thermal energy from the power generation device alone cannot cover the thermal energy of the hot water used in the hot water utilization equipment, the electric air conditioner is operated and replenished with the thermal energy from the electric air conditioner. Thermal energy replenishment control means;
When the thermal energy from the power generation device is greater than the thermal energy of hot water used in the hot water utilization equipment, the electric air conditioner is operated and the remaining heat energy is used to heat the refrigerant of the electric air conditioner. Thermal energy utilization control means used for
Cogeneration system characterized by having   2. The cogeneration system according to claim 1, wherein the constant output power is set in a range in which the power generator operates with high efficiency.   2. The constant output power according to claim 1, wherein the constant output power is automatically selected according to power consumption of the load device from a plurality of set values set in a range in which the power generator operates with high efficiency. Cogeneration system.   The electric heating device according to claim 1, further comprising an electric heating device provided between the hot water storage tank and the hot water use device and heating the hot water in the hot water storage tank and supplying the hot water to the hot water use device. Cogeneration system.   The electric desiccant air conditioner that adjusts the humidity of the air-conditioning target space using an adsorbent material according to claim 1, wherein the adsorbent material is regenerated by thermal energy of the power generator or the electric air conditioner. A featured cogeneration system.

Images