JP2017147889A - Power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system that, in supplying power generated by photovoltaic power generation to a demand destination, is capable of stably supplying the power while utilizing energy without a waste.SOLUTION: A power supply system 1 comprises: a photovoltaic power generation device 10; a power generator 22; a heat pump 30 including a compressor 31; a hot water storage tank 50 for storing a heat medium 51 capable of storing heat; and a control apparatus 83 for controlling the power generator 22 and the heat pump 30. Electric energy of power that is generated by the power supply system 1 and is to be supplied from a power supply unit 40 to a demand destination 80 is taken as supply side electric energy W2. When power generation side electric energy W1 output by the photovoltaic power generation device 10 is smaller than the supply side electric energy W2, an instruction of the control apparatus 83 makes the power generator 22 be operated on the basis of insufficient electric energy W3 corresponding to negative difference between the power generation side electric energy W1 and the supply side electric energy W2. At the time of the operation, waste heat Qc generated at an engine 21 of a cogeneration system 20 is stored in the heat medium 51 inside the hot water storage tank 50.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power supply system that supplies power with a photovoltaic power generation apparatus provided.

  Since solar power generation can generate power using renewable energy as renewable energy, solar power generation systems have been rapidly spreading in recent years for industrial and household use, and part of the power used by customers But it is funded by solar power. Since the power generated by the solar panel is direct-current power, a power conditioner, which is a type of inverter, is used to supply power from a photovoltaic power generation system to customers such as power loads in houses and transmission / distribution systems. Thus, DC power is converted to AC power.

  On the other hand, the output generated by the solar cell panel varies greatly depending on the weather and day and night depending on the sunlight. Therefore, if the output to be generated is smaller than the amount of power required at the customer, the insufficient power is compensated by, for example, a storage battery, but if the output is larger than the required amount of power, the power conditioner Control the power and adjust the output of AC power.

  Patent Document 1 discloses a technique for adjusting the power of a supply destination in accordance with fluctuations in output generated by a solar cell panel. Patent Document 1 is a heat pump system in which two heat pump devices are electrically connected by a direct current section. The first heat pump device exchanges direct current power input from the photovoltaic power generation device, the first generator driven by the first engine, the first compressor for the heat pump, the photovoltaic power generation device and the first generator. And a first inverter that converts the electric power to output. The second heat pump device includes a second generator driven by the second engine, a second compressor for heat pump, and a second inverter that converts DC power input from the generator into AC power and outputs the AC power. doing.

  In Patent Document 1, when the sum of the power generated by the solar power generation device and the first generator exceeds the set power (rated capacity) of the first inverter, the set power is AC power by the first inverter. To be output to the AC system. Further, the sum of the excess power corresponding to the amount exceeding the set power and the power generated by the second generator is converted into AC power by the second inverter and output to the AC system. .

  Such control of the first inverter and the second inverter is performed by the control unit. Thereby, even if the sum of the power generated by the solar power generator and the power generated by the first generator exceeds the set power of the first inverter, without changing the amount of power generated by the first generator, It is said that the operation of the heat pump system can be continued.

JP 2011-61960 A

  However, in the technique of adjusting the output of the AC power after conversion by the power conditioner, heat is generated in the electric circuit when the DC power is controlled and converted to the suppressed AC power. This heat is released, heat energy is lost, and the energy of sunlight cannot be used effectively.

  Moreover, in patent document 1, when the output produced | generated by a solar power generation device exceeds the rated capacity of a 1st inverter, the excess electric power is converted into alternating current power by a 2nd inverter. Although fluctuations in output due to power generation are absorbed, Patent Document 1 is not a system that effectively utilizes thermal energy generated from a compressor or an engine.

  The present invention has been made to solve the above-described problems, and in supplying power generated by solar power generation to a demand destination, energy is used without waste and power is stably supplied. An object of the present invention is to provide a power supply system capable of performing the above.

In order to achieve the above object, a power supply system according to the present invention has the following configuration.
(1) In a power supply system including a solar power generation device that generates power using sunlight, a power generation device that generates power, and a heat pump having a compressor that operates with an electric motor, a heat medium capable of storing heat is stored. A heat storage tank, and a control device that controls the power generation device and the heat pump, and when supplying the power generated by the power supply system toward a demand destination, from the power supply unit serving as the terminal, Assuming that the amount of power supplied to the demand destination is the supply-side power amount, when the power generation-side power amount output by the power generation by the solar power generation device is smaller than the supply-side power amount, the control device command The power generator is operated based on a shortage of energy corresponding to a negative difference between the power generation side power amount and the supply side power amount, and is generated in the power generation device during operation. That heat is being accumulated in the heat medium of the heat storage tank, characterized by.
(2) In the power supply system described in (1), when the power generation side power amount is larger than the supply side power amount, the heat pump causes the power generation side power amount and the supply side to be in accordance with a command from the control device. The heat pump is operated with electric power based on a surplus electric energy corresponding to a positive difference from the electric energy, and heat generated by the heat pump is stored in the heat medium in the heat storage tank during operation.
(3) In the power supply system described in (1) or (2), the heat storage tank is a hot water storage tank using water as the heat medium.
(4) In the power supply system described in any one of (1) to (3), the power generation device is a generator that generates power by driving an engine, and the fuel used for the engine is gas. It is characterized by being.
(5) In the power supply system described in any one of (1) to (3), the power generation device is a fuel cell.

The operation and effect of the power supply system of the present invention having the above configuration will be described.
(1) In a power supply system including a solar power generation device that generates power using sunlight, a power generation device that generates power, and a heat pump having a compressor that operates with an electric motor, a heat medium capable of storing heat is stored. A heat storage tank and a control device for controlling the power generation device and the heat pump, and when supplying the power generated by the power supply system to the customer, from the power supply unit serving as the terminal to the customer Assuming that the amount of power supplied is the supply-side power amount, when the power generation-side power amount output by the power generation by the photovoltaic power generation device is smaller than the supply-side power amount, the power generation device The heat generated in the power generator is stored in the heat medium in the heat storage tank during operation based on the shortage of power corresponding to the negative difference between the power on the side and the power on the supply side. , Characterized by. Due to this feature, even if the power generation by the solar power generation device fluctuates greatly depending on the amount of sunshine, due to the difference in the amount of sunlight, the power generation side power generated by the solar power generation device complements the power generation device. The generated amount of power corresponding to the amount of insufficient power becomes the amount of power required by the customer, and can be stably supplied from the power supply unit to the customer. In addition, when the power generation device supplements the amount of power that is less than the supply-side power required by the customer, for example, the operation of the engine that is the power source of the generator or the heat generation during fuel cell power generation Since the heat energy obtained by the above can be stored in the heat medium in the hot water tank, the heat stored in the heat medium can also be used effectively.

  Therefore, according to the power supply system of the present invention, when supplying power generated by solar power generation to a demand destination, energy can be used without waste and power can be stably supplied. Has an effect.

In the power supply system described in (2), when the power generation side power amount is larger than the supply side power amount, the heat pump corresponds to a positive difference between the power generation side power amount and the supply side power amount according to a command from the control device. The heat generated by the heat pump is stored in the heat medium in the heat storage tank during operation, and is operated with electric power based on the surplus electric power. With this feature, among the power generation-side power generated by the solar power generation device, the power for the supply-side power can be stably supplied from the power supply unit to the customer, and the supply side required by the customer Since the amount of surplus power that exceeds the amount of power is used as the power source of the heat pump, the energy obtained from sunlight can be used without waste. Furthermore, since the heat energy obtained by the operation of the heat pump can be stored in the heat medium in the hot water storage tank, the heat stored in the heat medium can also be used effectively.

In the power supply system described in (3), the heat storage tank is a hot water storage tank using water as a heat medium. With this feature, the water in the hot water storage tank is based on, for example, heat generated from an engine of a generator that is a power generation device, heat exhausted by power generated by a fuel cell that is a power generation device, or heat dissipation from a heat pump. After being heated to about 90 ° C and stored, if the heat is radiated in a temperature band such as 80 to 90 ° C, the heat source is the heat source, such as a hot water supply facility or an air conditioning facility that performs air conditioning. (Energy source) can be used. In particular, heat in a temperature range of 80 to 90 ° C. has a high potenshell energy, and can be supplied as it is to a heat source such as an air conditioner and is easy to manage. Therefore, it is suitable for supplying to a heat source such as an air conditioner. Therefore, it is desirable that the heat medium is stored at about 90 ° C. in the hot water tank.

In the power supply system described in (4), the power generation device is a generator that generates power by driving the engine, and fuel used for the engine is gas. With this feature, the exhaust gas generated from the engine does not generate sulfur oxide (SOx), which is one of the causes of acid rain, and the generation of nitrogen oxide (NOx) can be suppressed to a relatively low level. Further, among the city gas, particularly in the case of natural gas, the generation of carbon dioxide (CO ₂ ), which is one of the causes of global warming, can be suppressed as compared with the case of fuel with oil or coal. In addition, natural gas can be effectively used without waste in multiple stages as energy, high-pressure steam or low-pressure steam, hot water, and energy.

In the power supply system described in (5), the power generation device is a fuel cell. Due to this feature, for example, since the fuel cell generates power by directly converting chemical energy of fuel such as city gas into electric energy, energy loss can be suppressed to a lower level and highly efficient power generation can be performed. it can. In addition, since no carbon dioxide (CO ₂ ) is generated and the only byproduct generated after the electrochemical reaction between hydrogen and oxygen is water, power generation by the fuel cell is environmentally friendly.

It is a figure which shows typically the concept of the electric power supply system which concerns on Example 1 of embodiment. FIG. 5 is a diagram schematically illustrating the concept of the power supply system according to the second embodiment, as in FIG. 1. It is a figure which shows typically the concept of the electric power supply system which concerns on the modification of Example 1. FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a power supply system according to the present invention will be described in detail with reference to the drawings. The power supply system according to the present embodiment will be described with reference to a case where power is supplied to demand destinations such as hospitals, buildings, large commercial facilities, apartment houses, and detached houses for general households. FIG. 1 is a diagram schematically illustrating a concept of a power supply system according to an embodiment. FIG. 1 is a diagram illustrating a case where a generator that generates power by driving an engine is configured as the first embodiment. However, the same parts as those in the configurations of the second embodiment and the modified example of the first embodiment are illustrated. Will be described with reference to FIG.

  As shown in FIG. 1, the power supply system 1 includes a solar power generation device 10, a generator 22 (power generation device), a heat pump 30, a heat storage tank 50, and the like. The solar power generation device 10 is a device that includes one or more power generation modules in which a plurality of power generation cells (not shown) are arranged on a glass substrate, and generates power using sunlight. A power generation cell is an element that directly converts light energy generated by incident light of the sun into electrical energy. For example, a single crystal type, a polycrystalline type, a thin film type, an amorphous type, a dye sensitized type, a multi-junction type, and the like are well known. It consists of technology. The power generation module is formed by electrically connecting a plurality of power generation cells in series, and the power generated by the solar power generation device 10 is DC power.

  The heat pump 30 is, for example, an air heat utilization heat pump or the like, and includes a compressor 31 that is operated by an electric motor (not shown), a condenser, an expansion valve, an evaporator, and the like, and is configured by a well-known technique. The heat pump 30 is electrically connected to a control device 83 of the EMS 81 described later. The compressor 31 is operated by electric power based on the surplus power amount W4 of the solar power generation device 10 to be described later. In the heat pump 30, the heat medium is compressed by the compressor 31 to become a high-temperature and high-pressure gas, dissipated by heat exchange by the condenser, and the released heat is supplied to the heat medium 51 stored in the heat storage tank 50. Is done. In the heat pump 30, the heat medium after heat radiation is injected through the expansion valve, sent to the evaporator, absorbs heat from the surrounding outside air, and becomes a low-temperature and low-pressure gaseous state.

  The heat storage tank stores a heat medium 51 capable of storing heat. Specifically, the heat storage tank is a hot water storage tank 50 using the heat medium 51 as water. In addition, not only the water which is the heat medium 51 is stored in the heat storage tank, but the heat storage material sealed in the filling container may be accommodated in the heat storage tank together with the heat medium 51. This heat storage material performs heat storage or heat dissipation by utilizing the input and output of heat generated by state change or chemical reaction.

  That is, the heat storage material is a latent heat storage material that stores or releases heat by using the input and output of latent heat associated with phase change, and a chemical heat storage material that stores and releases heat using the input and output of reaction heat accompanying a chemical reaction with water. It is also possible to store heat in the heat storage material or to release heat from the heat storage material by transferring heat to and from the heat medium 51 through the filling container.

  When such a latent heat storage material or the like is accommodated in the hot water storage tank 50 together with the heat medium 51, for example, in the amount of stored heat when the temperature is raised from 80 ° C. to 90 ° C., the latent heat storage material or the like has the same volume. It has the physical property which can hold | maintain a larger amount of heat storage, such as exceeding about several to 10 times with respect to the amount of heat storage 42kJ in the case of heating up water. Therefore, in the hot water storage tank 50 using such a latent heat storage material or the like, the size of the entire tank is compared with, for example, a conventional heat storage tank (hot water storage tank), for example, about 1/3 to 1/4, It can be made compact. Further, the structure of the heat storage tank can be simplified.

  Next, an energy management system 81 (hereinafter abbreviated as “EMS (Energy Management System) 81”) will be described. The EMS 81 is introduced at a demand destination 80 of power generated by the power supply system 1. Specifically, when the customer 80 is, for example, a hospital, a building, a large commercial facility, an apartment house, or the like, the EMS 81 is a building energy management system (BEMS), and the customer 80 However, for example, in the case of a detached house for a general household, the EMS 81 is a home energy management system (HEMS).

  The EMS 81 includes a terminal device 82 and a control device 83. In the EMS 81, the control device 83 includes a generator 22 of the cogeneration system 20 (hereinafter abbreviated as “cogeneration 20”), a compressor 31 of the heat pump 30, a heat exchanger and a valve in the hot water tank 50, and the like. An electrical control unit (not shown) that performs operation control, the first watt-hour meter 65, and the second watt-hour meter 66 are electrically connected, and are also electrically connected to the terminal device 82. The control device 83 detects the amount of power measured by the first watt-hour meter 65 and the amount of power measured by the second watt-hour meter 66, and based on both detected amounts of power, the generator 22 And the operation of the compressor 31 are controlled. The cogeneration 20, the heat pump 30, and the hot water storage tank 50 can be automatically operated while being controlled by the control device 83 by the operation of the terminal device 82.

  Although not shown in FIG. 1, in the EMS 81, in addition to the cogeneration 20, the heat pump 30, the hot water storage tank 50, the first watthour meter 65, and the second watthour meter 66, the control device 83 is connected to sunlight. The power generation apparatus 10 and, for example, air conditioning equipment, home appliances, and the like, may be electrically connected to each power load used by the customer 80 and connected to each other via a communicable line. As a result, the terminal device 82 uses the individual power used by the customer 80 such as the solar power generation device 10, the cogeneration 20, the heat pump 30, and the hot water tank 50 as well as the air conditioning equipment and home appliances exemplified above. It is possible to confirm the energy (power consumption) consumed for each load. In addition, it becomes possible to operate air conditioning equipment, home appliances, and the like that are centrally managed by constructing a network through the terminal device 82 by remote control or automatic control.

Example 1
Next, the power supply system 1 according to the first embodiment will be described. The first embodiment is a cogeneration system 20 that generates power from a generator 22 by driving an engine 21, and converts the DC power generated by the solar power generation device 10 into AC power and transmits the AC power to a power supply unit. 1. The power supply system 1 is mainly intended for power demand destinations 80 such as hospitals, buildings, large commercial facilities, and apartment houses.

  In the first embodiment, the generator 22 is configured in the cogeneration 20 and generates power by driving an engine 21 that is a power source. In the present embodiment, the engine 21 is a power generation gas turbine engine that uses city gas as fuel, such as compressed natural gas or liquefied petroleum gas (LPG). As in the first embodiment, the cogeneration 20 including the gas turbine engine type engine 21 has an advantage that the output of the generator 22 can be relatively increased even if the cogeneration 20 is small in size.

  In addition, the cogeneration 20 which can use city gas and oil together as the fuel of the engine 21 may be used. The engine 21 of the cogeneration 20 may be, for example, an internal combustion engine such as a gas engine or a diesel engine in addition to a gas turbine engine that is a kind of internal combustion engine. Furthermore, the power source is not limited to the internal combustion engine, and may be an external combustion engine such as a steam boiler, a steam turbine, or a Stirling engine.

  As shown in FIG. 1, in the power supply system 1, the hot water storage tank 50 uses water (heat medium 51), for example, based on exhaust heat Qc from the engine 21 of the cogeneration 20 or heat dissipation Qp from the heat pump 30. Hot water heated to about 90 ° C. is stored.

  Further, the solar power generation device 10 is connected in series with the power supply unit 40 via the inverter 61 (the first inverter 61 in FIG. 2), the first watthour meter 65, and the second watthour meter 66. Yes. Between the first watt hour meter 65 and the second watt hour meter 66, the generator 22 of the cogeneration 20 is provided on the second power system 3 connected in parallel with the first power system 2. Although not shown, the cogeneration inverter is electrically connected to the generator 22 as necessary regardless of whether it is built in or externally attached to the cogeneration 20, and an AC voltage generated by the generator 22 is described later. To a predetermined voltage value required for power supply to the power supply unit 40.

  The compressor 31 of the heat pump 30 is provided on the third power system 4 connected in parallel with the first power system 2 between the first watt-hour meter 65 and the second watt-hour meter 66. Although not shown, the heat pump inverter is electrically connected to the compressor 31 as necessary regardless of whether the heat pump inverter is built in or externally attached to the heat pump 30, and the AC voltage converted by the inverter 61 is converted into the compressor. The voltage is varied to a predetermined voltage value suitable for power supply to 31.

  The inverter 61 (first inverter 61) converts the DC power generated by the solar power generation device 10 into AC power. The first watt-hour meter 65 measures the output of the AC power converted by the inverter 61 (first inverter 61). The second watt-hour meter 66 is a sum of outputs of AC power transmitted through the first power system 2 or outputs of AC power transmitted from both the first power system 2 and the second power system 3. Measure. The power supply unit 40 is a part that serves as a terminal for supplying the power generated by the power supply system 1 to the customer 80.

  Here, based on the DC power generated by the solar power generation device 10, the power amount measured by the first watt hour meter 65 with the output converted into AC power is defined as the power generation side power amount W1, and the power supply unit The amount of power supplied from 40 to the customer 80 and measured by the second watt-hour meter 66 is defined as a supply-side power amount W2. Further, when the power generation-side power amount W1 is smaller than the supply-side power amount W2, the power amount corresponding to the negative difference between the power-generation-side power amount W1 and the supply-side power amount W2 is set as an insufficient power amount W3. On the contrary, when the power generation side power amount W1 is larger than the supply side power amount W2, the power amount corresponding to the positive difference between the power generation side power amount W1 and the supply side power amount W2 is set as the surplus power amount W4.

  In the power supply system 1, when the power generation-side power amount W1 is smaller than the supply-side power amount W2, the generator 22 of the cogeneration 20 is operated based on the insufficient power amount W3 in accordance with a command from the control device 83 of the EMS 81. Sometimes, the exhaust heat Qc generated in the engine 21 is stored in the heat medium 51 in the hot water storage tank 50. At this time, the compressor 31 of the heat pump 30 does not operate, no heat is generated in the heat pump 30, and the heat dissipation Qp is zero.

  On the other hand, when the power generation-side power amount W1 is larger than the supply-side power amount W2, the compressor 31 of the heat pump 30 is operated by the power based on the surplus power amount W4 according to a command from the control device 83 of the EMS 81. The heat dissipation Qp generated at 30 is stored in the heat medium 51 in the hot water storage tank 50. At this time, the engine 21 of the cogeneration 20 does not operate, and the exhaust heat Qc from the engine 21 is zero. Of course, the generator 22 does not generate electricity.

(Example 2)
Next, a power supply system 1A according to the second embodiment will be described with reference to FIG. FIG. 2 is a diagram schematically illustrating the concept of the power supply system according to the second embodiment. Example 2 is a cogeneration system 20A that generates power using a fuel cell 25 (power generation device). The power supply system 1A converts DC power generated by the solar power generation device 10 into AC power and transmits the AC power to a power supply unit. It is. The power supply system 1A according to the second embodiment is mainly intended for a power demand destination 80, for example, a detached house for general households, and has a second inverter 62, and the cogeneration 20A Except for the configuration, it is the same as the power supply system 1 according to the first embodiment.

  The fuel cell 25 is configured in the cogeneration 20A. The fuel cell 25 is a battery that generates electricity by directly converting chemical energy of the fuel into electrical energy by causing an electrochemical reaction between hydrogen extracted from city gas or the like as fuel and oxygen in the air, for example. The electric power generated by the fuel cell 25 is direct current. The second inverter 62 converts the DC power generated by the fuel cell 25 into AC power. In the fuel cell 25, the responsiveness of the electrochemical reaction between hydrogen and oxygen is good, and the fuel cell 25 can generate power at any time by continuously supplying hydrogen contained in city gas or the like and oxygen in the air. Therefore, the fuel cell 25 has a controller (not shown) that controls the execution and stop of the electrochemical reaction. This control unit operates based on a command from the control device 83 of the EMS 81.

  As shown in FIG. 2, in the power supply system 1 </ b> A, the hot water storage tank 50 uses water (heat medium 51), for example, based on exhaust heat Qc generated during power generation of the fuel cell 25 and heat dissipation Qp from the heat pump 30. The hot water heated to about 90 ° C. is stored.

  Similarly to the power supply system 1 of the first embodiment, even in the power supply system 1A, when the power generation-side power amount W1 is smaller than the supply-side power amount W2, the cogeneration 20A causes the shortage power amount W3 by the command from the control device 83 of the EMS 81. The exhaust heat Qc generated in the fuel cell 25 is stored in the heat medium 51 in the hot water tank 50 during operation. At this time, the compressor 31 of the heat pump 30 does not operate, no heat is generated in the heat pump 30, and the heat dissipation Qp is zero.

  On the other hand, when the power generation-side power amount W1 is larger than the supply-side power amount W2, the compressor 31 of the heat pump 30 is operated by the power based on the surplus power amount W4 according to a command from the control device 83 of the EMS 81. The heat dissipation Qp generated at 30 is stored in the heat medium 51 in the hot water storage tank 50. At this time, the fuel cell 25 in the cogeneration 20A does not generate power, and the exhaust heat Qc from the cogeneration 20A is zero.

(Modification)
Next, a power supply system 1B according to a modification of the first embodiment will be described with reference to FIG. FIG. 3 is a diagram schematically illustrating the concept of a power supply system according to a modification. The third embodiment is a cogeneration 20 that generates power from the generator 22 by driving the engine 21 as in the first embodiment. However, after the direct-current power generated by the solar power generation device 10 passes through the power supply unit 40, It is the electric power supply system 1B which converts into alternating current power.

  As shown in FIG. 3, in the power supply system 1B, the photovoltaic power generation apparatus 10 includes a power supply unit via a DC / DC converter (not shown), a first watthour meter 65A, and a second watthour meter 66A. 40 is connected in series. The DC / DC converter transforms the direct-current voltage generated by the solar power generation device 10 into a predetermined voltage value required for power transmission. Between the first watt hour meter 65A and the second watt hour meter 66A, the generator 22 of the cogeneration 20 is provided on the second power system 3A connected in parallel with the first power system 2A. A converter (not shown) is connected between 20 and the second watt-hour meter 66A. This converter converts AC power generated by the generator 22 of the cogeneration 20 into DC power.

  The compressor 31 of the heat pump 30 includes a first inverter 61A on a third power system 4A connected in parallel with the first power system 2A between the first wattmeter 65A and the second wattmeter 66A. It is provided with. The charging device 70 is connected in parallel with the first power system 2 </ b> A between the second watt-hour meter 66 </ b> A and the power supply unit 40.

  The first inverter 61 </ b> A converts the DC power generated by the photovoltaic power generator 10 into AC power necessary as a power source for the compressor 31. The first watt-hour meter 65 </ b> A measures the output of DC power generated by the solar power generation device 10. The second watt-hour meter 66A is a sum of outputs of DC power transmitted via the first power system 2A or outputs of DC power transmitted from both the first power system 2A and the second power system 3A. Measure.

  The charging device 70 is a device that charges DC power generated by the power supply system 1B to an object to be charged using DC power as a power source, such as an electric vehicle or a hybrid type vehicle equipped with an engine and a motor. is there. The second inverter 62A converts the DC power generated by the power supply system 1B into AC power required by the customer 80.

  Here, the electric power measured by the first watt-hour meter 65A with the output by the DC power generated by the solar power generation device 10 is defined as the power generation-side power amount W1, and the power measured by the second watt-hour meter 66A. Let the amount be the supply-side power amount W2. Note that there is a second inverter 62A between the power supply unit 40 and the customer 80, and a power loss occurs when the second inverter 62A converts DC power into AC power, for example, about 5%. Therefore, it is preferable that the magnitude of the AC power supplied from the power supply unit 40 to the customer 80 is one that takes into account this power loss.

  When the power generation-side power amount W1 is smaller than the supply-side power amount W2, the power amount corresponding to the negative difference between the power-generation-side power amount W1 and the supply-side power amount W2 is set as an insufficient power amount W3. On the contrary, when the power generation side power amount W1 is larger than the supply side power amount W2, the power amount corresponding to the positive difference between the power generation side power amount W1 and the supply side power amount W2 is set as the surplus power amount W4.

  In the power supply system 1B, when the power generation side power amount W1 is smaller than the supply side power amount W2, the generator 22 of the cogeneration 20 is operated based on the insufficient power amount W3 by the control device 83 of the EMS 81. Exhaust heat Qc generated at 21 is stored in the heat medium 51 in the hot water storage tank 50. At this time, the compressor 31 of the heat pump 30 does not operate, no heat is generated in the heat pump 30, and the heat dissipation Qp is zero.

  On the other hand, when the power generation-side power amount W1 is larger than the supply-side power amount W2, the compressor 31 of the heat pump 30 is operated by the power based on the surplus power amount W4 by the control device 83 of the EMS 81 and is generated in the heat pump 30 during operation. The heat radiation Qp to be stored is stored in the heat medium 51 in the hot water storage tank 50. At this time, the engine 21 of the cogeneration 20 does not operate, and the exhaust heat Qc from the engine 21 is zero. Of course, the generator 22 does not generate electricity.

  Next, functions and effects of the power supply systems 1, 1A, 1B according to the present embodiment will be described. The power supply systems 1, 1 </ b> A, and 1 </ b> B are heat pumps including a solar power generation device 10 that generates power using sunlight, a power generation device (power generator 22 or fuel cell 25) that generates power, and a compressor 31 that operates with an electric motor. 30, a hot water tank 50 for storing a heat medium 51 capable of storing heat, and a control device 83 for controlling the generator 22 and the heat pump 30 (or the fuel cell 25 and the heat pump 30). I have. In supplying the power generated by the power supply systems 1, 1 </ b> A, 1 </ b> B toward the customer 80, the power supplied from the power supplier 40 serving as the terminal to the customer 80 is determined as the supply-side power. When the amount W2 is set, the power generation side power amount W1 output by the power generation by the solar power generation apparatus 10 is smaller than the supply side power amount W2. In the power supply systems 1 and 1B, the power generation side power amount W1 and the supply side power amount The generator 22 is operated on the basis of the insufficient electric energy W3 corresponding to the negative difference with W2, and the exhaust heat Qc generated in the engine 21 of the cogeneration 20 during operation is stored in the heat medium 51 in the hot water storage tank 50. It is characterized by that. Further, in the power supply system 1A, the fuel cell 25 is operated based on the insufficient power amount W3 corresponding to the negative difference between the power generation side power amount W1 and the supply side power amount W2, and the fuel cell of the cogeneration 20A is operated during the operation. The exhaust heat Qc generated at 25 is stored in the heat medium 51 in the hot water storage tank 50.

  Due to this feature, even if the power generation by the solar power generation device 10 fluctuates greatly in season, weather, day and night due to the difference in the amount of sunlight, the power generation side power amount W1 generated by the solar power generation device 10 complementarily. The power corresponding to the insufficient power amount W3 generated by the cogeneration 20 and 20A becomes the power amount required by the customer 80 and can be stably supplied from the power supply unit 40 to the customer 80. In particular, even when an electric product having a relatively large power consumption such as an air conditioner is used during the daytime and a time when the power consumption is large at the customer 80, the generator 22 of the cogeneration 20 or the fuel cell 25 of the cogeneration 20A is used. However, since the power corresponding to the insufficient power amount W3 can be supplemented, the customer 80 can stably obtain the power supply by the power supply systems 1, 1A, 1B. Further, when the cogeneration 20, 20 </ b> A supplements the power for the insufficient power amount W <b> 3 that is less than the supply-side power amount W <b> 2 required by the customer 80, the thermal energy obtained by the operation of the engine 21, the power generation of the fuel cell 25 Since the heat energy obtained at the time of the electrochemical reaction between hydrogen and oxygen can be stored in the heat medium 51 in the hot water tank 50, the heat stored in the heat medium 51 can also be used effectively. .

  Therefore, according to the power supply systems 1, 1 </ b> A, and 1 </ b> B according to the present embodiment, when supplying power generated by solar power generation to the customer 80, energy is used without waste and power is stably supplied. There is an excellent effect of being able to.

  Further, in the power supply systems 1, 1A, 1B according to the present embodiment, when the power generation side power amount W1 is larger than the supply side power amount W2, a positive difference between the power generation side power amount W1 and the supply side power amount W2 is obtained. The compressor 31 is operated by electric power based on the corresponding surplus electric power W4, and the heat radiation Qp generated by the heat pump 30 is stored in the heat medium 51 in the hot water tank 50 during operation.

  With this feature, among the power generation-side power amount W1 generated by the solar power generation device 10, the power for the supply-side power amount W2 can be stably supplied from the power supply unit 40 to the customer 80, and the customer 80 Since the power for the surplus power amount W4 that exceeds the supply-side power amount W2 required for the heat pump 30 is used as the power source of the heat pump 30, the energy obtained from sunlight can be used without waste. Furthermore, since the heat energy obtained by the operation of the heat pump 30 can be stored in the heat medium 51 in the hot water storage tank 50, the heat stored in the heat medium 51 can also be used effectively.

  In the power supply systems 1, 1 </ b> A, and 1 </ b> B according to the present embodiment, the heat storage tank is a hot water storage tank 50 using the heat medium 51 as water. With this feature, in the power supply systems 1 and 1B, the heat medium 51 (water) in the hot water storage tank 50 is, for example, based on the exhaust heat Qc from the engine 21 of the cogeneration 20 or the heat dissipation Qp from the heat pump 30. After being heated to about ℃ and stored, if the heat is radiated in a temperature band such as 80 to 90 ℃, the heat from the heat medium 51 is used as a heat supply source, such as a hot water supply facility or an air conditioning facility for air conditioning (Energy source) can be used. In the power supply system 1A, the heat medium 51 (water) in the hot water storage tank 50 is, for example, about 90 ° C. based on the exhaust heat Qc from the fuel cell 25 of the cogeneration 20A and the heat dissipation Qp from the heat pump 30. After being heated and stored, if the heat is radiated in a temperature range such as 80 to 90 ° C., the heat radiated by the heat medium 51 is used as a heat supply destination, such as a hot water supply facility or a heat source (energy source) such as an air conditioner for air conditioning. ). As described above, the heat in the temperature range of 80 to 90 ° C. has a particularly high potential energy and can be supplied to a heat source such as an air conditioner as it is and can be easily managed. Since the temperature is suitable, it is desirable that the heat medium 51 is stored at about 90 ° C. in the hot water storage tank 50.

In the power supply systems 1 and 1B according to Examples 1 and 1B of the present embodiment, the power generation device is the generator 22 that generates power by driving the engine 21, and the fuel used for the engine 21 is gas. It is characterized by. Due to this feature, the exhaust gas generated from the engine 21 does not generate sulfur oxide (SOx), which is one of the causes of acid rain, and the generation of nitrogen oxide (NOx) can be suppressed to a relatively low level. Further, among the city gas, particularly in the case of natural gas, the generation of carbon dioxide (CO ₂ ), which is one of the causes of global warming, can be suppressed as compared with the case of fuel with oil or coal. In addition, natural gas can be effectively used without waste in multiple stages as energy, high-pressure steam or low-pressure steam, hot water, and energy.

Moreover, in the electric power supply system 1A which concerns on Example 2 of this embodiment, the electric power generating apparatus is the fuel cell 25, It is characterized by the above-mentioned. Due to this feature, the fuel cell 25 generates electricity by directly converting chemical energy of fuel such as city gas into electric energy, so that energy loss can be suppressed to a lower level and highly efficient power generation can be performed. . In addition, since no carbon dioxide (CO ₂ ) is generated and water is the only byproduct generated after the electrochemical reaction between hydrogen and oxygen, power generation by the fuel cell 25 is environmentally friendly.

  In the above, the present invention has been described according to the first and second embodiments and the modified examples of the embodiment. However, the present invention is not limited to the first and second embodiments and the modified examples, and the gist thereof is described. The present invention can be changed and applied as appropriate without departing from the scope.

  For example, in Examples 1 and 2 and the modification of the embodiment, the concept of the power supply systems 1, 1 </ b> A, and 1 </ b> B is illustrated in FIGS. 1 to 3, but the concept of the power supply system is limited to FIGS. Is not to be done. That is, in the power supply system, the generator and the heat pump configured in the cogeneration system or the like are connected in parallel between the photovoltaic power generation apparatus and the power supply unit, respectively. However, what is necessary is just to be connected with the thermal storage tank. And a cogeneration system etc. should generate | occur | produce the electric power for insufficient electric energy, and the heat medium in a thermal storage tank should just be heat-stored with the heat which arises at the time of electric power generation. The heat pump may be operated by electric power corresponding to the surplus electric power, and the heat medium in the heat storage tank may be stored by heat generated from the heat pump.

1,1A, 1B Power supply system 10 Photovoltaic generator 20, 20A Cogeneration (cogeneration system)
21 Engine 22 Generator (power generation device)
25 Fuel cell (power generator)
30 Heat pump 31 Compressor 40 Power supply unit 50 Hot water storage tank (heat storage tank)
51 Water (heat medium)
80 Demand 83 Control equipment (control equipment)
W1 Power generation side power amount W2 Supply side power amount W3 Insufficient power amount W4 Surplus power amount Qc Waste heat (heat generated in engine or fuel cell)
Qp heat dissipation (heat generated by heat pump)

Claims (5)

In a power supply system comprising a solar power generation device that generates power by sunlight, a power generation device that generates power, and a heat pump that has a compressor that operates with an electric motor,
A heat storage tank for storing a heat medium capable of storing heat, and a control device for controlling the power generation device and the heat pump,
When supplying the electric power generated by the electric power supply system to the demand destination, when the magnitude of the electric power to be supplied to the demand destination from the power supply section serving as the terminal is the supply-side power amount,
When the power generation side electric energy output by the power generation by the solar power generation device is smaller than the supply side electric energy,
In response to a command from the control device, the power generation device is operated based on an insufficient power amount corresponding to a negative difference between the power generation side power amount and the supply side power amount, and is generated in the power generation device during operation. Heat is stored in the heat medium in the heat storage tank,
Power supply system characterized by The power supply system according to claim 1,
When the power generation side electric energy is larger than the supply side electric energy,
According to a command from the control device, the heat pump is operated with electric power based on a surplus electric energy corresponding to a positive difference between the power generation side electric energy and the supply side electric energy. During operation, heat generated by the heat pump is generated. Heat is stored in the heat medium in the heat storage tank,
Power supply system characterized by In the electric power supply system according to claim 1 or 2,
The heat storage tank is a hot water storage tank using the heat medium as water;
Power supply system characterized by In the electric power supply system according to any one of claims 1 to 3,
The power generator is a generator that generates power by driving an engine,
The fuel used for the engine is gas,
Power supply system characterized by In the electric power supply system according to any one of claims 1 to 3,
The power generator is a fuel cell;
Power supply system characterized by

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