Electric power generation system

Abstract

To provide an electric power generation system which can effectively use energy of a Peltier chiller.SOLUTION: An electric power generation system comprises a fuel cell, an inverter converting DC current generated by the fuel cell, a Peltier chiller performing heat transfer between a primary side fluid and a secondary side fluid using a Peltier element, thereby performing cooling operation of cooling the secondary side fluid or heating operation of heating the secondary side fluid, and exhaust piping which is connected to the Peltier chiller and inside which air, the primary side fluid discharged after the heat transfer from the Peltier chiller, passes. The exhaust piping includes: a first flow path for discharging the primary side fluid in such a way that the primary side fluid hits the inverter; and a second flow path for discharging the primary side fluid in such a way that the primary side fluid does not hit the inverter. When the Peltier chiller performs the cooling operation, the primary side fluid passes through the second flow path; and when the Peltier chiller performs the heating operation, the primary side fluid passes through the first flow path.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to power generation systems. [Background technology]

[0002] Patent Document 1 discloses a power generation system that uses a fuel cell. The power generation system includes an adsorption chiller that exerts a cooling capacity by adsorbing and desorbing a refrigerant to an adsorbent. In the power generation system, the air used by the fuel cell is preheated by the condensation heat generated when the refrigerant is adsorbed in the adsorption chiller. This can improve the energy efficiency of the power generation system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-153758 A Summary of the Invention [Problem to be solved by the invention]

[0004] In systems that generate power mainly from fuel cells, Peltier chillers are sometimes used instead of adsorption refrigerators. Peltier chillers are chillers that use Peltier elements and can heat as well as cool a target medium. When heating a target medium, cold air that is lower in temperature than the atmospheric temperature is generated. On the other hand, the power generation system described in Patent Document 1 does not use cold air. As such, no technology has been considered for effectively utilizing the cold air.

[0005] The present disclosure has been made to solve the above-mentioned problems. An object of the present disclosure is to provide a power generation system that can effectively utilize the energy of a Peltier chiller in a system that generates power using a fuel cell. [Means for solving the problem]

[0006] The power generation system of the present disclosure comprises a fuel cell, an inverter that converts the direct current generated by the fuel cell into alternating current, a Peltier chiller that operates with electricity generated by the fuel cell and performs a cooling operation to cool the secondary side fluid or a heating operation to heat the secondary side fluid by transferring heat between a primary side fluid and a secondary side fluid using a Peltier element, and an exhaust piping connected to the Peltier chiller and through which air, which is the primary side fluid discharged from the Peltier chiller after heat transfer, passes, the exhaust piping having a first flow path that discharges the primary side fluid so that it hits the inverter, and a second flow path that discharges the primary side fluid so that it does not hit the inverter, and the primary side fluid passes through the second flow path when the Peltier chiller is performing a cooling operation, and the primary side fluid passes through the first flow path when the Peltier chiller is performing a heating operation. Effect of the Invention

[0007] According to the present disclosure, when the Peltier chiller is performing a heating operation, the primary fluid passes through the first flow path and hits the inverter. This primary fluid is cold air that is lower in temperature than the atmospheric temperature. The inverter is cooled by this cold air. Therefore, the energy of the Peltier chiller can be effectively utilized in a system that generates electricity using a fuel cell. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a power generation system according to a first embodiment. [Diagram 2] FIG. 2 is a schematic diagram of a Peltier chiller of the power generation system in the first embodiment. [Diagram 3] 2 is a diagram showing an outline of a damper circuit of the power generation system in the first embodiment. FIG. [Figure 4] FIG. 2 is a schematic diagram of a Peltier chiller of the power generation system in the first embodiment performing a heating operation. [Diagram 5] FIG. 2 is a schematic diagram of a Peltier chiller of the power generation system in the first embodiment performing a cooling operation. [Figure 6]FIG. 2 is a schematic diagram of a modified example of the power generation system 1 in the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The embodiments for carrying out the present disclosure will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals. The duplicated description of the parts will be appropriately simplified or omitted.

[0010] Embodiment 1 Fig. 1 is a schematic diagram of a power generation system in accordance with embodiment 1. Fig. 2 is a schematic diagram of a Peltier chiller of the power generation system in accordance with embodiment 1.

[0011] The power generation system 1 shown in Fig. 1 is a cogeneration system that produces electricity and hot water in stages from fuel gas such as city gas or LP gas. For example, the power generation system 1 is installed in a building where people live or work, such as a residence or a building. The power generation system 1 includes a power conditioning unit 2, a hot water supply unit 16, and a Peltier chiller 30. In Fig. 1, the solid arrows indicate piping and paths for fluids, such as gas or liquid. The dashed arrows indicate paths for electricity.

[0012] The power conditioning unit 2 produces electricity and hot water from the fuel gas. The power conditioning unit 2 includes a fuel cell unit 3, an inverter 10, a heat exchanger 11, a reforming water tank 12, a reforming water pump 13, a fuel boost pump 14, and a cathode side air fan 15.

[0013] The fuel cell unit 3 is a fuel cell that generates electricity from an oxidation reaction between oxygen molecules in the air and fuel gas. In this embodiment, a SOFC type fuel cell that uses a solid oxide as an electrolyte is exemplified. The fuel cell unit 3 includes a desulfurizer 4, a reformer 5, a reactor 6, and a burner 7.

[0014] Fuel gas is supplied to the desulfurizer 4 from a supply port through a fuel supply pipe 20. A fuel boost pump 14 is provided in the fuel supply pipe 20. The fuel gas pressurized by the fuel boost pump 14 is blown into the desulfurizer 4. The desulfurizer 4 desulfurizes the fuel gas, i.e., removes sulfur components from the fuel gas.

[0015] The fuel gas desulfurized by the desulfurizer 4 is blown into the reformer 5 through an inlet pipe 21. The reformer 5 is supplied with reforming water from a reforming water tank 12 through a reforming water pipe 22. A reforming water pump 13 is provided midway through the reforming water pipe 22. The reformer 5 is blown with reforming water pressurized by the reforming water pump 13. The reformer 5 reacts the fuel gas with the reforming water to generate reformed fuel gas. The reformed fuel gas is a fuel gas that contains more components used in the oxidation reaction of the fuel cell than before reforming. For example, the reformed fuel gas contains more hydrogen molecule gas than before reforming.

[0016] The reactor 6 has a fuel electrode section 6a and an air electrode section 6b. Reformed fuel gas is blown into the fuel electrode section 6a. Air pressurized by the cathode-side air fan 15 is blown into the air electrode section 6b through an intake piping. For example, oxygen ions move through the electrolyte between the fuel electrode section 6a and the air electrode section 6b, causing an oxidation reaction generally represented by the following formula (1). In the reactor 6, electricity is extracted based on the potential difference generated between the fuel electrode section 6a and the air electrode section 6b by the oxidation reaction. Hereinafter, the extraction of electricity by this oxidation reaction is also referred to as power generation. 2H 2 +O 2 =2H 2 O (1)

[0017] The fuel gas that has reacted in the fuel electrode portion 6a and the air that has reacted in the air electrode portion 6b are blown into the burner 7. The burner 7 combusts the fuel gas and the air to generate high-temperature combustion gas.

[0018] The inverter 10 converts the direct current, which is the electricity generated in the reactor 6, into an alternating current. For example, the alternating current converted by the inverter 10 is used as a commercial power source in a residence or the like.

[0019] Combustion gas is blown into the heat exchanger 11 from the burner 7. The heat exchanger 11 exchanges heat between the combustion gas and water to generate hot water, which is heated water. The water is supplied from a water source such as a water pipe or a hot water supply unit 16. The combustion gas after heat exchange is exhausted from the heat exchanger 11.

[0020] Hot water supply unit 16 includes hot water storage tank 17, waste heat recovery pump 18, and auxiliary hot water heater 19. Hot water heated by heat exchanger 11 or the like is stored in hot water storage tank 17. For example, in hot water storage tank 17, the hot water is separated into a plurality of layers having different temperatures in the vertical direction due to a temperature difference. Hot water storage tank 17 is connected to heat exchanger 11 by a supply pipe 23 and a return pipe 24. Hot water storage tank 17 is supplied with water or hot water from a water source such as a water pipe, heat exchanger 11, and auxiliary hot water heater 19. For example, the hot water stored in hot water storage tank 17 is used as hot water or water for heating in a residence.

[0021] Waste heat recovery pump 18 is provided midway through supply pipe 23. Waste heat recovery pump 18 generates a water flow that passes through hot water storage tank 17, supply pipe 23, heat exchanger 11, and return pipe 24 in this order. Auxiliary water heater 19 is a heating burner. For example, auxiliary water heater 19 is a burner that burns gas (not shown) with air. When the heat quantity of the hot water stored in hot water storage tank 17 decreases, auxiliary water heater 19 heats the hot water inside hot water storage tank 17 or water from a water source and supplies it to hot water storage tank 17.

[0022] The Peltier chiller 30 is a chiller that uses a Peltier element to perform heat exchange. The Peltier chiller 30 is a non-freon type chiller, so there is no risk of ozone layer destruction compared to chillers that use refrigerants such as freon. In addition, the Peltier chiller 30 does not use a compressor, so it makes much less noise during operation compared to chillers that use refrigerants such as freon.

[0023] The Peltier chiller 30 transfers heat between a primary fluid and a secondary fluid. The primary fluid is air. The primary fluid is taken in through an air inlet 30a and discharged through an exhaust port 30b. In this example, the secondary fluid is water. The secondary fluid is taken in through a water supply port 30c and discharged through a drain port 30d. The Peltier chiller 30 can perform a cooling operation to cool the secondary fluid and a heating operation to heat the secondary fluid. As an example, hot water, which is the secondary fluid, is taken in through a water supply port 30c from a hot water tank 17 via a feed pipe 25. The hot water that is accurately temperature-adjusted and discharged through a drain port 30d is then used as hot water in a residence or the like via a feed pipe 26.

[0024] As shown in FIGS. 1 and 2, the Peltier chiller 30 includes a heat transfer device 31, an exhaust fan 32, a water-side pump 33, a converter 34, a temperature sensor 35, a temperature regulator 36, and a switching circuit 37.

[0025] The heat transfer device 31 transfers heat between the primary fluid and the secondary fluid by using a Peltier element. The transfer of heat is performed by passing an electric current through the Peltier element. At this time, the direction of the heat transfer differs depending on the direction of the electric current. The heat transfer device 31 is provided with a plurality of sets of an N-type semiconductor 31a, a P-type semiconductor 31b, and a metal body 31c. FIG. 2 shows an overview of one of the sets. As an example, the N-type semiconductor 31a and the P-type semiconductor 31b can exchange heat with the primary fluid between the intake port 30a and the exhaust port 30b. The metal body 31c can exchange heat with the secondary fluid between the water supply port 30c and the drain port 30d. In the Peltier element, heat transfer occurs between the N-type semiconductor 31a and the P-type semiconductor 31b and the metal body 31c. Due to a temperature gradient between the primary fluid and the secondary fluid generated by the heat transfer, heat exchange occurs between the Peltier element and the primary fluid, and heat exchange occurs between the Peltier element and the secondary fluid.

[0026] The exhaust fan 32 is provided between the heat transfer device 31 and the exhaust port 30b. The exhaust fan 32 generates a flow of a primary fluid from the intake port 30a through the heat transfer device 31 and the exhaust port 30b. The water-side pump 33 is provided between the water supply port 30c and the heat transfer device 31. The water-side pump 33 generates a flow of a secondary fluid from the water supply port 30c through the heat transfer device 31 and the drain port 30d.

[0027] The converter 34 is a DC / DC converter. The converter 34 is electrically connected between the reactor 6 of the fuel cell unit 3 and the Peltier chiller 30. The converter 34 supplies the direct current generated by the fuel cell unit 3 to the Peltier chiller 30. At this time, the converter 34 converts the voltage of the direct current generated by the fuel cell unit 3, etc. into values ​​suitable for use by the Peltier chiller 30.

[0028] As shown in FIG. 2, the temperature sensor 35 is provided in the middle of the feed pipe 26. The temperature sensor 35 measures the temperature of the secondary fluid. The temperature regulator 36 is electrically connected between the converter 34 and the heat transfer device 31. The temperature regulator 36 receives the measurement result of the temperature of the secondary fluid from the temperature sensor 35. The temperature regulator 36 adjusts the temperature of the secondary fluid so that the difference between the temperature command value O of the secondary fluid from a control device (not shown) and the measured temperature from the temperature sensor 35 becomes small. At this time, the temperature regulator 36 adjusts the temperature of the discharged secondary fluid by controlling the magnitude of the current flowing from the converter 34 to the heat transfer device 31, etc. For example, the temperature regulator 36 controls the amount of heat transferred per specified time in the heat transfer device 31 by switching the current ON and OFF, and adjusts the temperature of the discharged secondary fluid. The temperature control performed by the temperature regulator 36 may be performed by directly adjusting the magnitude of the current, etc. In addition, any method such as PID control may be adopted as the method of temperature control.

[0029] The switching circuit 37 is electrically connected between the converter 34 and the heat transfer device 31. Specifically, the switching circuit 37 is connected to the positive and negative poles of the converter 34. The switching circuit 37 is connected to the N-type semiconductor 31a and the P-type semiconductor 31b of the heat transfer device 31, respectively. As shown in FIG. 2, for example, the temperature regulator 36 is provided between the switching circuit 37 and the N-type semiconductor 31a. The switching circuit 37 switches the connection state between the positive and negative poles of the converter 34 and the N-type semiconductor 31a and the P-type semiconductor 31b of the heat transfer device 31 by two contacts X1, thereby switching the direction of the current flowing through the heat transfer device 31. Specifically, the switching circuit 37 changes the direction of the current flowing through the heat transfer device 31 between a heating direction and a cooling direction. The heating direction is the direction of the current in which the heat transfer device 31 performs a heating operation. The cooling direction is the direction opposite to the heating direction and is the direction of current flow in which the cooling operation is performed in the heat transfer device 31 .

[0030] As particularly shown in FIG. 1, the power generation system 1 further includes an exhaust pipe 100 and a damper unit 60.

[0031] The exhaust piping 100 has an exhaust pipe 101, a first cold air pipe 102, a second cold air pipe 103, a first hot air pipe 104, a second hot air pipe 105, and an outside air pipe 106. The exhaust pipe 101 is connected to the exhaust port 30b, and is a pipe that exhausts the primary side fluid from the Peltier chiller 30.

[0032] One end of the first cold air duct 102 is connected to the exhaust duct 101 by a branch duct 110. An opening at the other end of the first cold air duct 102 opposite to the one end faces the inverter 10. In this manner, the first cold air duct 102 discharges the primary fluid so that it hits the inverter 10. Note that the first cold air duct 102 may be connected to the inside of the inverter 10, or a heat sink or the like for cooling the inside of the inverter 10 may be provided midway along the first cold air duct 102. Even in this case, the primary fluid hits the inverter 10.

[0033] One end of the second cold air duct 103 is connected to a midway portion of the first cold air duct 102 by a branch pipe 110. The other end of the second cold air duct 103 is directed toward the converter 34. In this manner, the second cold air duct 103 discharges a portion of the primary-side fluid so that the primary-side fluid hits the converter 34. The second cold air duct 103 may be connected to the inside of the converter 34, or a heat sink or the like for cooling the inside of the converter 34 may be provided midway along the second cold air duct 103. Even in this case, the primary-side fluid hits the converter 34.

[0034] One end of the first hot air pipe 104 is connected to a branched portion of the exhaust pipe 101 and the first cold air pipe 102 by a branch pipe 111. The other end of the first hot air pipe 104 is connected to the air electrode part 6b of the reactor 6 as an intake pipe. A cathode side air fan 15 is provided midway along the first hot air pipe 104.

[0035] One end of second hot air pipe 105 is connected to a midway portion of first hot air pipe 104 by a branch pipe 112. The other end of second hot air pipe 105 is connected to an intake portion of auxiliary water heater 19.

[0036] One end of the outside air pipe 106 is connected to a midway portion of the first hot air pipe 104 by a branch pipe 113. Specifically, one end of the outside air pipe 106 is connected to a midway portion located between the connection portion of the first hot air pipe 104 with the exhaust pipe 101 and the connection portion with the second hot air pipe 105. The other end of the outside air pipe 106 is open to the outside air. At the other end of the outside air pipe 106, the outside air can be freely taken into the inside of the outside air pipe 106.

[0037] The damper unit 60 includes a cold air damper 61, a hot air damper 62, an intake damper 63, and a damper circuit 64. The cold air damper 61, the hot air damper 62, and the intake damper 63 are all motor dampers that can open and close the pipes by blocking or opening the air passage in the pipes. Note that the damper circuit 64 is omitted from illustration in Figs. 1 and 2.

[0038] The cold air damper 61 is provided in the first cold air duct 102 between the connection portion with the exhaust duct 101 and the connection portion with the second cold air duct 103. The cold air damper 61 is capable of opening and closing the portion where the first cold air duct 102 is installed.

[0039] The hot air damper 62 is provided in the first hot air pipe 104 between the connection part with the exhaust pipe 101 and the connection part with the outside air pipe 106. The hot air damper 62 is capable of opening and closing the installation part of the first hot air pipe 104.

[0040] The intake damper 63 is provided in the outside air pipe 106 between the connection portion with the first hot air pipe 104 and the portion open to the outside air. The intake damper 63 is capable of opening and closing the portion where the outside air pipe 106 is installed.

[0041] The damper circuit 64 can control the opening and closing operations of the cold air damper 61, the hot air damper 62, and the intake damper 63. The damper circuit 64 operates in conjunction with the switching circuit 37.

[0042] Next, the damper circuit 64 will be described with reference to FIG. FIG. 3 is a diagram showing an outline of a damper circuit of the power generation system in the first embodiment.

[0043] In the damper circuit 64, the selector switch COS controls the supply of current to the coil CX1 of the relay X1. The relay X1 corresponds to the two contacts X1 of the switching circuit 37 shown in FIG. 2. When the selector switch COS is in the ON state, a current flows through the coil CX1 of the relay X1. In this state, a current flows in the cooling direction in the switching circuit 37 not shown in FIG. 3. That is, when the selector switch COS is in the ON state, the Peltier chiller 30 performs a cooling operation. Also, when the selector switch COS is in the OFF state, a current flows in the heating direction in the switching circuit 37, and the Peltier chiller 30 performs a heating operation.

[0044] In the damper circuit 64, the cooling contact X1a and the heating contact X1b correspond to the relay X1. The cooling contact X1a is an a-contact. The heating contact X1b is a b-contact. When the selector switch COS is in the ON state, the Peltier chiller 30 performs cooling operation, the cooling contact X1a is closed, and the heating contact X1b is open. When the selector switch COS is in the OFF state, the Peltier chiller 30 performs heating operation, the cooling contact X1a is open, and the heating contact X1b is closed.

[0045] The cold air damper 61, the hot air damper 62, and the intake damper 63 are closed when no current flows through their coils, and are open when current flows through their coils. When the cooling contact X1a is closed, current flows through the coil C62 of the hot air damper 62, and the hot air damper 62 opens. When the heating contact X1b is closed, current flows through the coil C61 of the cold air damper 61 and the coil C63 of the intake damper 63, and the cold air damper 61 and the intake damper 63 open.

[0046] In this way, the damper circuit 64 works in conjunction with the switching circuit 37. Specifically, when a current flows in a cooling direction through the switching circuit 37, the damper circuit 64 closes the cold air damper 61 and the intake damper 63 and opens the hot air damper 62. When a current flows in a heating direction through the switching circuit 37, the damper circuit 64 opens the cold air damper 61 and the intake damper 63 and closes the hot air damper 62.

[0047] Next, the flow path of the primary side fluid, which changes depending on the operation of the Peltier chiller 30, will be described. Fig. 4 is a schematic diagram of the Peltier chiller of the power generation system in embodiment 1 performing a heating operation. Fig. 5 is a schematic diagram of the Peltier chiller of the power generation system in embodiment 1 performing a cooling operation. Note that in Figs. 4 and 5, the temperature regulator 36 is omitted from illustration.

[0048] 4 shows the flow path of the exhaust pipe 100 when the Peltier chiller 30 is performing heating operation. The Peltier chiller 30 transfers heat from a primary fluid to a secondary fluid. The secondary fluid, hot water, is heated while its temperature is controlled by a temperature regulator 36. The heated hot water is used in a residence or the like. Heat is removed from the primary fluid by the Peltier element. As a result, cool air at a temperature lower than the atmospheric temperature is exhausted from the exhaust port 30b of the Peltier chiller 30.

[0049] At this time, the cold air damper 61 and the intake damper 63 are open. The hot air damper 62 is closed. As a result, in the exhaust pipe 100, the first flow path F1, the third flow path F3, and the outside air flow path Fo are formed as exhaust flow paths for the primary side fluid.

[0050] The first flow path F1 is a path that passes through the exhaust pipe 101, the branch pipe 111, and the first cold air pipe 102 including the branch pipe 110 in this order, and hits the inverter 10. After passing through the first flow path F1, the primary side fluid hits the inverter 10 and is exhausted to the atmosphere.

[0051] The third flow path F3 is a flow path that branches off from the first flow path F1 at the branch pipe 110, passes through the second cold air duct 103, and then hits the converter 34. After passing through the third flow path F3, the primary side fluid hits the converter 34 and is exhausted to the atmosphere. Note that the third flow path F3 may be regarded as including a part of the first flow path F1, that is, as a flow path that passes through the exhaust pipe 101, the branch pipe 111, a part of the first cold air duct 102, the branch pipe 110, and the second cold air duct 103 in this order.

[0052] The outside air flow path Fo is a path that functions as an intake pipe. The outside air flow path Fo is a flow path that passes through the outside air pipe 106, the branch pipe 113, and a part of the first hot air pipe 104 including the branch pipe 112 in this order, and is taken into the air electrode part 6b of the reactor 6. The outside air flow path Fo also includes a flow path that branches at the branch pipe 112, passes through the second hot air pipe 105, and is taken into the auxiliary water heater 19.

[0053] The inverter 10 and the converter 34 are cooled by the cold air that has passed through the first flow path F1 or the third flow path F3. At this time, the air taken in from the outside is used for power generation in the air electrode portion 6b. Also, the air taken in from the outside is used as combustion air for the burner in the auxiliary water heater 19.

[0054] 5 shows a flow path of the exhaust pipe 100 when the Peltier chiller 30 is performing a cooling operation. The Peltier chiller 30 transfers heat from the secondary fluid to the primary fluid. The hot water, which is the secondary fluid, is cooled while its temperature is controlled by the temperature regulator 36. The cooled hot water is used in residences and the like. Heat is imparted to the primary fluid by the Peltier element. Hot air at a temperature higher than the atmospheric temperature is exhausted from the exhaust port 30b of the Peltier chiller 30.

[0055] At this time, the cold air damper 61 and the intake damper 63 are closed. The hot air damper 62 is open. As a result, in the exhaust pipe 100, the second flow path F2 and the fourth flow path F4 are formed as exhaust flow paths for the primary fluid. Note that, when the cooling operation is performed, the primary fluid does not pass through the first flow path F1 and the third flow path F3.

[0056] The second flow path F2 is a flow path that discharges the primary fluid so as not to hit the inverter 10. The second flow path F2 is a flow path that passes through the exhaust pipe 101, the branch pipe 111, and the first hot air pipe 104 including the branch pipes 113 and 112 in this order, and is taken into the air electrode unit 6b. The second flow path F2 is a flow path that functions as an intake pipe. That is, after passing through the second flow path F2, the primary fluid is used for power generation in the air electrode unit 6b.

[0057] The fourth flow path F4 is a flow path that branches off from the second flow path F2 at branch pipe 112, passes through second hot air pipe 105, and is then taken into auxiliary water heater 19. After passing through fourth flow path F4, the primary side fluid is used as combustion air for the burner in auxiliary water heater 19. Note that the fourth flow path F4 may be considered to include a portion of the second flow path F2, that is, to be considered to be a flow path that passes through exhaust pipe 101, branch pipe 111, a portion of first hot air pipe 104 including branch pipe 113, branch pipe 112, and second hot air pipe 105 in that order.

[0058] In the reactor 6, air having a higher temperature than the atmosphere is used for power generation, so power generation efficiency is improved. In the auxiliary water heater 19, air having a higher temperature than the atmosphere is used for combustion, so energy efficiency is improved.

[0059] According to the above-described first embodiment, the power generation system 1 includes a fuel cell, an inverter 10, a Peltier chiller 30, and an exhaust pipe 100. The exhaust pipe 100 has a first flow path F1 and a second flow path F2. When the Peltier chiller 30 is performing a cooling operation, the primary fluid, which is hot air, passes through the second flow path F2 that does not hit the inverter 10. When the Peltier chiller 30 is performing a heating operation, the primary fluid, which is cold air, passes through the first flow path F1 that hits the inverter 10. The inverter 10 generates heat when converting electric power. The cold air cools the inverter 10. The average operating temperature of the inverter 10 is reduced by the cooling, so that the inverter 10 is less likely to break down. In this way, the energy of the Peltier chiller 30 can be effectively utilized in a system that generates power using a fuel cell.

[0060] Furthermore, the Peltier chiller 30 transfers heat using the current generated by the fuel cell. In this way, the electricity used by the Peltier chiller 30 is generated near the Peltier chiller 30, so the loss of electricity during transmission is reduced compared to when electricity transmitted from a power plant is used. This achieves energy conservation and can reduce CO2 emissions. Furthermore, even in the event of a power outage in which electricity cannot reach homes and the like from the power plant, the Peltier chiller 30 can still operate using gas or the like.

[0061] The power generation system 1 further includes a burner 7, a heat exchanger 11, and a hot water tank 17. In the burner 7, the fuel gas used in the fuel cell is burned and discharged as exhaust heat. In the heat exchanger 11, the exhaust heat is exchanged with hot water to heat the hot water. The heated hot water is stored in the hot water tank 17. In a heating operation, the Peltier chiller 30 heats the hot water supplied from the hot water tank 17 as a secondary fluid. Compared to when the hot water is supplied directly from the hot water tank 17, the Peltier chiller 30 controls the temperature of the hot water with higher accuracy. As a result, the temperature of the hot water supplied to a residence or the like can be controlled with higher accuracy.

[0062] The power generation system 1 further includes a converter 34. When the Peltier chiller 30 is performing heating operation using the current converted by the converter 34, cold air, which is a primary fluid, is discharged from the Peltier chiller 30 through the third flow path F3 of the exhaust piping 100 and hits the converter 34. The converter 34 is cooled by the cold air. This allows the converter 34 to operate at a lower temperature, and the failure rate of the converter 34 can be reduced.

[0063] Also, when the Peltier chiller 30 is performing cooling operation, the hot air, which is the primary fluid that has passed through the second flow path F2 of the exhaust pipe 100, is supplied to the air electrode 6b of the fuel cell as air for reaction. In the fuel cell, air at a higher temperature than the atmosphere is used for the reaction. This improves the energy efficiency of the fuel cell.

[0064] The power generation system 1 further includes a switching circuit 37, a cold air damper 61, a hot air damper 62, and a damper circuit 64. The damper circuit 64 and the switching circuit 37 operate in conjunction with each other. When the current flowing through the switching circuit 37 is in a cooling direction, the damper circuit 64 closes the cold air damper 61 and opens the hot air damper 62. In this case, the hot air, which is the primary fluid, does not pass through the first flow path F1 but passes through the second flow path F2. When the current flowing through the switching circuit 37 is in a heating direction, the damper circuit 64 opens the cold air damper 61 and closes the hot air damper 62. In this case, the cold air, which is the primary fluid, does not pass through the second flow path F2 but passes through the first flow path F1. In this way, the operating state of the Peltier chiller 30 and the flow path of the exhaust pipe 100 can be switched simultaneously.

[0065] When the Peltier chiller 30 is performing a cooling operation, the intake damper 63 may be in a moderately open state rather than being fully closed. In this state, a mixture of the primary fluid and the atmosphere may pass through the second flow path F2 and the fourth flow path F4. Even in this case, air with a higher temperature than the atmosphere may be used for power generation and combustion.

[0066] The fuel cell is not limited to the SOFC type, and the combustion gas used in the fuel cell and the chemical reactions occurring in the fuel cell are not limited to the examples shown in this embodiment.

[0067] The secondary fluid of the Peltier chiller 30 may be supplied from a water source such as a water supply, instead of the hot water tank 17. The secondary fluid of the Peltier chiller 30 may be any fluid other than water.

[0068] It should be noted that the power generation system 1 does not necessarily need to be provided with a hot water supply facility using the hot water tank 17. FIG. 6 is a schematic diagram of a modification of the power generation system 1 according to the first embodiment. As shown in FIG. 6, the exhaust pipe 100 in the first embodiment can also be applied to a power generation system 1 that is not provided with a hot water tank 17 or the like.

[0069] To summarize the above explanation, possible configurations of the technology according to the present disclosure include the configurations listed below as appendices. (Appendix 1) A fuel cell; an inverter for converting a direct current generated by the fuel cell into an alternating current; a Peltier chiller that operates using electricity generated by the fuel cell and that performs a cooling operation for cooling the secondary fluid or a heating operation for heating the secondary fluid by transferring heat between a primary fluid and a secondary fluid using a Peltier element; an exhaust pipe connected to the Peltier chiller, through which air, which is the primary fluid discharged from the Peltier chiller after heat transfer, passes; Equipped with The exhaust pipe is a first flow path that discharges the primary fluid so that the primary fluid hits the inverter; a second flow path that discharges the primary fluid so that the primary fluid does not hit the inverter; having A power generation system in which the primary side fluid passes through the second flow path when the Peltier chiller is performing the cooling operation, and the primary side fluid passes through the first flow path when the Peltier chiller is performing the heating operation. (Appendix 2) a burner for burning a fuel gas used for generating electricity in the fuel cell; a heat exchanger for exchanging heat between exhaust heat from the burner and hot water; a hot water storage tank for storing the hot water heated by the heat exchanger; Further comprising: The power generation system according to claim 1, wherein the Peltier chiller heats hot water supplied from the hot water storage tank as the secondary fluid during the heating operation. (Appendix 3) a converter electrically connected between the fuel cell and the Peltier chiller, the converter supplying a direct current generated by the fuel cell to the Peltier chiller; Further comprising: The Peltier element of the Peltier chiller transfers heat by the direct current supplied from the converter, The exhaust pipe is a third flow passage branching from the second flow passage and discharging a portion of the primary fluid to the converter; Further comprising: The power generation system according to claim 1 or 2, wherein the primary side fluid does not pass through the third flow path when the Peltier chiller is performing the cooling operation, and the primary side fluid passes through the third flow path when the Peltier chiller is performing the heating operation. (Appendix 4) the second flow path is connected to a pipe that supplies air to be used for power generation to the fuel cell; The power generation system according to any one of claims 1 to 3, wherein the primary side fluid is supplied to the fuel cell as air for reaction through the second flow path when the Peltier chiller is performing the cooling operation. (Appendix 5) A switching circuit that changes the direction of a current flowing through a Peltier element of the Peltier chiller between a cooling direction in which the cooling operation is performed and a heating direction in which the heating operation is performed; a cold air damper provided in the middle of the first flow path and configured to open and close the first flow path; A hot air damper provided in the middle of the second flow path and configured to open and close the second flow path; a damper circuit that switches between an opening and closing operation of the cold air damper and the hot air damper in cooperation with the switching circuit; Further comprising: The damper circuit includes: When the current flowing through the switching circuit is in the cooling direction, the cold air damper is closed and the hot air damper is opened. The power generation system according to claim 4, wherein when the current flowing through the switching circuit is in the heating direction, the cold air damper is opened and the hot air damper is closed. [Explanation of symbols]

[0070] 1 power generation system, 2 power conditioner unit, 3 fuel cell unit, 4 desulfurizer, 5 reformer, 6 reactor, 6a fuel electrode section, 6b air electrode section, 7 burner, 10 inverter, 11 heat exchanger, 12 reformed water tank, 13 reformed water pump, 14 fuel boost pump, 15 cathode side air fan, 16 hot water supply unit, 17 hot water storage tank, 18 waste heat recovery pump, 19 auxiliary hot water heater, 20 fuel supply pipe, 21 blow pipe, 22 reformed water pipe, 23 outflow pipe, 24 return pipe, 25 delivery pipe, 26 delivery pipe, 30 Peltier chiller, 30a intake port, 30b exhaust port, 30c water supply port, 30d drain port, 31 Heat transfer device, 31a N-type semiconductor, 31b P-type semiconductor, 31c metal body, 32 exhaust fan, 33 water side pump, 34 converter, 35 temperature sensor, 36 temperature regulator, 37 switching circuit, 60 damper unit, 61 cold air damper, 62 hot air damper, 63 intake damper, 64 damper circuit, 100 exhaust pipe, 101 exhaust pipe, 102 first cold air duct, 103 second cold air duct, 104 first hot air duct, 105 second hot air duct, 106 outside air duct, 110,111,112,113 branch pipe, COS selector switch, F1 first flow path, F2 second flow path, F3 third flow path, F4 fourth flow path, Fo outside air flow path, X1 contact, X1 relay, X1a cooling contact, X1b heating contact

Claims

1. A fuel cell; an inverter for converting a direct current generated by the fuel cell into an alternating current; a Peltier chiller that operates using electricity generated by the fuel cell and that performs a cooling operation for cooling the secondary fluid or a heating operation for heating the secondary fluid by transferring heat between a primary fluid and a secondary fluid using a Peltier element; an exhaust pipe connected to the Peltier chiller, through which air, which is the primary fluid discharged from the Peltier chiller after heat transfer, passes; Equipped with The exhaust pipe is a first flow path that discharges the primary fluid so that the primary fluid hits the inverter; a second flow path that discharges the primary fluid so that the primary fluid does not hit the inverter; having A power generation system in which the primary side fluid passes through the second flow path when the Peltier chiller is performing the cooling operation, and the primary side fluid passes through the first flow path when the Peltier chiller is performing the heating operation.

2. a burner for burning a fuel gas used for generating electricity in the fuel cell; a heat exchanger for exchanging heat between exhaust heat from the burner and hot water; a hot water storage tank for storing the hot water heated by the heat exchanger; Further comprising: The power generation system according to claim 1 , wherein the Peltier chiller heats hot water supplied from the hot water storage tank as the secondary fluid during the heating operation.

3. a converter electrically connected between the fuel cell and the Peltier chiller, the converter supplying a direct current generated by the fuel cell to the Peltier chiller; Further comprising: The Peltier element of the Peltier chiller transfers heat by the direct current supplied from the converter, The exhaust pipe is a third flow passage branching from the second flow passage and discharging a portion of the primary side fluid to impinge on the converter; Further comprising: The power generation system according to claim 1 or claim 2, wherein the primary side fluid does not pass through the third flow path when the Peltier chiller is performing the cooling operation, and the primary side fluid passes through the third flow path when the Peltier chiller is performing the heating operation.

4. the second flow path is connected to a pipe that supplies air to be used for power generation to the fuel cell; 3. The power generation system according to claim 1, wherein the primary fluid is supplied to the fuel cell as air for reaction through the second flow passage when the Peltier chiller is performing the cooling operation.

5. A switching circuit that changes the direction of a current flowing through a Peltier element of the Peltier chiller between a cooling direction in which the cooling operation is performed and a heating direction in which the heating operation is performed; a cold air damper provided in the middle of the first flow path and configured to open and close the first flow path; A hot air damper provided in the middle of the second flow path and configured to open and close the second flow path; a damper circuit that switches between an opening and closing operation of the cold air damper and the hot air damper in cooperation with the switching circuit; Further comprising: The damper circuit includes: When the current flowing through the switching circuit is in the cooling direction, the cold air damper is closed and the hot air damper is opened. The power generation system according to claim 4 , wherein when the current flowing through the switching circuit is in the heating direction, the cold air damper is opened and the hot air damper is closed.

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