JP7555242B2 - Power generation and hot water supply system - Google Patents

Description

This disclosure relates to a power generating hot water supply system.

A fuel cell system is known that supplies hot water by utilizing the electricity generated by a fuel cell module and the waste heat generated by the fuel cell module. This fuel cell system is used in combination with a heat source device such as a water heater (see Patent Document 1).

JP 2020-165582 A

Conventionally, when combining a fuel cell system and a heat source unit, each has been configured separately. Therefore, when combining a fuel cell system and a heat source unit, there is room for improvement in the combination, such as combining the respective configurations.

The purpose of this disclosure, made in consideration of the problems with the conventional technology described above, is to provide a power generating hot water supply system with high operating performance.

The power generating and hot water supply system according to one embodiment includes:
A fuel cell module;
a heat storage tank for storing a heat medium for heat exchange with the exhaust gas of the fuel cell module;
The fuel cell module is provided with a water heater that is positioned to be aligned with the fuel cell module in a direction perpendicular to the up-down direction and is capable of supplying hot water by using the heat medium stored in the heat storage tank.
Here, the power generating and hot water supply system is a fuel cell system that combines a fuel cell module and a hot water heater.

This disclosure makes it possible to provide a power generating hot water supply system with high operating performance.

1 is a schematic configuration diagram of a power generating hot water supply system according to an embodiment of the present invention. 2 is a cross-sectional view taken along the vertical direction of a support portion, showing an example of the arrangement of a fuel cell module, a heat storage tank, and a water heater in the power generating and hot water supply system of FIG. 1. 13 is a cross-sectional view taken along the vertical direction of the support, showing another example of the arrangement of the fuel cell module, the heat storage tank, and the water heater. FIG.

Embodiments of the present disclosure will now be described with reference to the drawings. The drawings used in the following description are schematic. The dimensional ratios and other details in the drawings do not necessarily correspond to the actual ones.

As shown in FIG. 1, the power generating and hot water supply system 10 according to one embodiment includes a fuel cell module 11, a heat storage tank 12, and a water heater 13. The power generating and hot water supply system 10 may further include a heat medium circulation path 14, a radiator 15, a heat medium pump 16, a gas supply path 17, a first water supply path 18, an exhaust port 19, a heat exchanger 21, a gas-liquid separator 22, a water tank 23, a gas intake port 26, a water intake port 27, and a second water supply path 29. As shown in FIG. 2, the power generating and hot water supply system 10 may further include a support portion 20, a hot water supply port 28, and a porous member 30.

The fuel cell module 11 may have a reformer and a cell stack. The reformer generates fuel such as hydrogen by causing a steam reforming reaction using gas supplied as raw fuel and water. The cell stack generates electricity through an electrochemical reaction using an oxidant such as oxygen contained in the air and the fuel generated by the reformer. The cell stack also generates water through an electrochemical reaction. Unreacted fuel and unreacted oxidant discharged from the cell stack are combusted to provide energy for the steam reforming reaction in the reformer. The water discharged from the cell stack is discharged from the fuel cell module 11 in the form of a high-temperature gas together with the combustion gas resulting from the combustion of the unreacted fuel and unreacted oxidant.

The exhaust gas discharged from the fuel cell module 11 may contain combustion gas and gaseous water. As shown in FIG. 1, the exhaust gas discharged from the fuel cell module 11 may be heat exchanged with a heat medium using a heat exchanger 21. The exhaust gas cooled by the heat exchange may be separated into gaseous exhaust gas and condensed liquid water by a gas-liquid separator 22. The separated exhaust gas may be discharged from the exhaust port 19 to the outside of the power generation hot water supply system 10. The separated water may be temporarily stored in a water tank 23 and then sent to the fuel cell module 11 as water to be used in the steam reforming reaction.

The heat storage tank 12 stores a heat medium. The heat medium is used for heat exchange with the exhaust gas discharged from the fuel cell module 11. The heat medium is, for example, a fluid with a large specific heat, such as water or antifreeze. In this embodiment, the heat medium is water. The heat medium stored in the heat storage tank 12 may circulate between the heat storage tank 12 and the heat exchanger 21. Here, the heat storage tank 12 may be provided with a dedicated supply path for taking in the heat medium water, or may take in the heat medium water from a branched first water supply path 18.

As shown in FIG. 2, in this embodiment, the heat storage tank 12 is located below the fuel cell module 11. Below the power generation and hot water supply system 10 means below in the vertical direction (hereinafter also referred to as the up-down direction) relative to the ground when the power generation and hot water supply system 10 is installed. Below the fuel cell module 11 means that the position in the up-down direction is the lower side of the fuel cell module 11, and the position in the direction perpendicular to the up-down direction is arbitrary.

Here, as shown in FIG. 3, the heat storage tank 12 may be configured to be located above the fuel cell module 11. In the present disclosure, the heat storage tank 12 is located above or below the fuel cell module 11.

As shown in FIG. 1, the water heater 13 can supply hot water by using the heat medium stored in the heat storage tank 12. The water heater 13 can supply hot water by, for example, heating water by heat exchange with the heat medium. In a configuration in which the heat medium is water, the heat medium may be directly supplied as hot water. The water heater 13 may have a burner that burns gas, and may be capable of heating using the burner when the heat medium alone is insufficient. The burner may heat the water by burning gas supplied as fuel. Exhaust gas from the combustion may be discharged from the water heater 13.

As shown in FIG. 2, the water heater 13 is positioned alongside the fuel cell module 11 in a direction perpendicular to the up-down direction. The water heater 13 may be positioned on either side of the fuel cell module 11 in a direction perpendicular to the up-down direction. In this disclosure, the water heater 13 is positioned to the left or right of the fuel cell module 11. The water heater 13 may be positioned close to the fuel cell module 11. Here, "close to" means that the two components are arranged close enough to each other for heat transfer. In this case, a solid heat medium may be present between the two components. Also, a solid heat medium need not be present between the two components, and the two components may be in contact.

As shown in FIG. 1, the heat medium circuit 14 may circulate a heat medium between the heat storage tank 12 and the heat exchanger 21. A portion of the heat medium circuit 14 may be connected to the heat exchanger 21 via a radiator 15 and a heat medium pump 16.

The radiator 15 may cool the heat medium extracted from the heat storage tank 12, in other words, the heat medium before heat exchange with the exhaust gas of the fuel cell module 11. The radiator 15 may have, for example, a fan with an adjustable rotation speed. The radiator 15 may be capable of adjusting the cooling of the heat medium by adjusting the rotation speed of the fan.

The heat medium pump 16 may supply the heat medium to the heat exchanger 21 by increasing the pressure of the heat medium.

The gas supply path 17 may have a single or multiple gas intake ports 26. The gas supply path 17 may branch into at least two paths. The branched gas supply path 17 may be connected to the fuel cell module 11 and the water heater 13. The gas supply path 17 may supply gas from the gas intake port 26 to the fuel cell module 11 and the water heater 13.

The first water supply path 18 may have a single or multiple water intake ports 27. The first water supply path 18 may be branched into at least two paths. The branched first water supply path 18 may be directly or indirectly connected to the fuel cell module 11 and the water heater 13. Specifically, the water that has passed through the first water supply path 18 may be indirectly supplied to the fuel cell module 11 via the water tank 23. Here, the second water supply path 29 is a water supply path that supplies water from the water tank 23 to the fuel cell module 11.

Furthermore, the first water supply line 18 may be connected to the water tank 23 via a purification device that purifies the water. Also, the first water supply line 18 may be directly connected to the water heater 13. The first water supply line 18 may supply water from the water intake port 27 to the fuel cell module 11 and the water heater 13.

As shown in FIG. 2, the gas intake port 26 and the water intake port 27 may be located away from the hot water supply port 28 from the water heater 13 in the vertical direction. More specifically, the gas intake port 26 and the water intake port 27 may be located closer to the heat storage tank 12 than the fuel cell module 11 and the water heater 13 in the vertical direction.

As shown in FIG. 1, the exhaust port 19 may be directly or indirectly connected to the fuel cell module 11 and the water heater 13. Specifically, the exhaust port 19 may be indirectly connected to the fuel cell module 11 via the gas-liquid separator 22. The exhaust port 19 may also be directly connected to the water heater 13. The exhaust port 19 may exhaust exhaust gas discharged from the fuel cell module 11 and exhaust gas discharged from the water heater 13 from the power generation and hot water supply system 10. The exhaust port 19 may exhaust exhaust air, which is air heated by the radiator 15 through heat exchange for cooling the heat medium.

As shown in FIG. 2, a porous member 30 may be provided inside the exhaust port 19. The porous member 30 sucks up water discharged from at least one of the water tank 23 and the water heater 13 by capillary action and evaporates it. For example, even if the water tank 23 overflows, the porous member 30 can suck up the water overflowing from the water tank 23 and evaporate it. The porous member 30 may evaporate the sucked up water using the heat of exhaust gas discharged from at least one of the fuel cell module 11 and the water heater 13. The porous member 30 may be composed of, for example, ceramic, cloth, resin such as sponge, etc., but is not limited to these.

2, the support unit 20 may support the heat storage tank 12 at a fixed position relative to the fuel cell module 11. The support unit 20 may be, for example, a part of a housing that houses the fuel cell module 11, the heat storage tank 12, and the water heater 13. The support unit 20 is not limited to a housing, and may be a framework, a fixing bracket, a plate, or the like that can support the heat storage tank 12 at a fixed position relative to the fuel cell module 11. The power generation and hot water supply system 10 may be installed in a pipe shaft of an apartment building or the like. The support unit 20 may support the heat storage tank 12 so that the heat storage tank 12 is located above or below the fuel cell module 11 in the pipe shaft.

The support portion 20 may be provided with rails. The rails allow at least a portion of the fuel cell module 11, the heat storage tank 12, and the water heater 13 to be pulled out in one direction perpendicular to the up-down direction, either separately or together.

In the power generating hot water system 10 according to the present embodiment, configured as described above, the water heater 13 is positioned so as to be aligned with the fuel cell module 11 in a direction perpendicular to the up-down direction. The heat of the fuel cell module 11 is transferred to the water heater 13, thereby heating the water and hot water supplied to the water heater 13. This makes it possible to reduce the amount of gas burned in the water heater 13, thereby providing a power generating hot water system 10 with high operating performance. Here, in order to enhance the effect of the water and hot water supplied to the water heater 13 being heated by heat transfer from the fuel cell module 11, part of the supply path for the water and hot water to the water heater 13 may pass near the fuel cell module 11.

Furthermore, the fuel cell module 11 is generally covered with insulation to maintain a high temperature. The water heater 13 is a type of heat source. Therefore, in the power generating and hot water supply system 10, the insulation covering the fuel cell module 11 that is provided between the fuel cell module 11 and the water heater 13 can be made thinner than the other insulation. This allows the power generating and hot water supply system 10 to be made smaller, making it easier to install the power generating and hot water supply system 10, for example, in a pipe shaft where space is limited.

In addition, in the power generation and hot water supply system 10, the heat storage tank 12 is located above or below the fuel cell module 11. However, the position of the heat storage tank 12 in the direction perpendicular to the up-down direction is arbitrary. This allows for greater design freedom in the arrangement of the heat storage tank 12 in the power generation and hot water supply system 10. For example, the heat storage tank 12 can be easily arranged in close proximity to parts of the gas supply path 17, the first water supply path 18, and the second water supply path 29.

Here, the heat storage tank 12 can be positioned below the fuel cell module 11. This is because, for example, if the heat medium leaks from the heat storage tank 12, this can avoid any effects on the fuel cell module 11 and the water heater 13. Also, a structure in which the heat storage tank 12 is positioned below the fuel cell module 11 makes it easier to transport the power generating and hot water supply system 10 before installation, especially when the support section 20 is a housing. Because the heat storage tank 12 of the power generating and hot water supply system 10 before installation is not filled with heat medium, the center of gravity of the power generating and hot water supply system 10 is in a high position. This makes it easier for the installer to transport the power generating and hot water supply system 10.

In addition, in the power generating hot water supply system 10, the water tank 23 can be located close to the heat storage tank 12. Heat from the heat storage tank 12 is transferred to the water tank 23, thereby preventing the water tank 23 from freezing. The water tank 23 may be structured to be fitted into a part of the heat storage tank 12 as shown in FIG. 2. In order to increase the space utilization efficiency within the housing and reduce the size of the power generating hot water supply system 10, the water tank 23 may be shaped like a rectangular parallelepiped. For the same reason, the heat storage tank 12 may also be shaped like a rectangular parallelepiped.

In addition, in the power generating hot water supply system 10, a portion of the water supply passages (first water supply passage 18 and second water supply passage 29) can be located close to the heat storage tank 12. By transmitting heat from the heat storage tank 12 to the water supply passages, it is possible to prevent the water supply passages from freezing. Here, only a portion of the first water supply passage 18 or the second water supply passage 29 may be located close to the heat storage tank 12.

In addition, in the power generation and hot water supply system 10, a portion of the gas supply line 17 can be located close to the heat storage tank 12. Heat from the heat storage tank 12 is transferred to the gas supply line 17, thereby preventing the gas supply line 17 from freezing. In addition, since heated gas is supplied to the water heater 13, the ignition ability of the water heater 13 is improved, and the generation of nitrogen oxides and carbon monoxide can be reduced.

Although the present disclosure has been described based on various drawings and examples, it should be noted that a person skilled in the art would easily be able to make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these modifications and corrections are included within the scope of the present disclosure.

REFERENCE SIGNS LIST 10 Power generating hot water supply system 11 Fuel cell module 12 Heat storage tank 13 Hot water heater 14 Heat medium circulation path 15 Radiator 16 Heat medium pump 17 Gas supply path 18 First water supply path 19 Exhaust port 20 Support 21 Heat exchanger 22 Gas-liquid separator 23 Water tank 26 Gas intake port 27 Water intake port 28 Hot water supply port 29 Second water supply path 30 Porous member

Claims (11)

A fuel cell module;
a heat storage tank for storing a heat medium for heat exchange with the exhaust gas of the fuel cell module;
a water heater having a burner, the water heater being arranged to be aligned with the fuel cell module in a direction perpendicular to the up-down direction and capable of supplying hot water by using the heat medium stored in the heat storage tank;
a water tank for storing water to be used in a steam reforming reaction for generating fuel to be used in the fuel cell module;
The water tank is located adjacent to the thermal storage tank . 2. The power generating and hot water supply system according to claim 1 , wherein a portion of a water supply passage that supplies the water from the water tank to the fuel cell module is located adjacent to the heat storage tank. The power generating and hot water supply system according to claim 1 or 2 , further comprising a porous member that sucks up and evaporates water discharged from at least one of the water tank and the hot water heater by capillary action. 4. The power generating and hot water supply system according to claim 3 , wherein the porous member evaporates the sucked up water by using heat of exhaust gas discharged from at least one of the fuel cell module and the hot water heater. 5. The power generating and hot water supply system according to claim 1, wherein a portion of a gas supply path that supplies gas to the fuel cell module and the hot water heater is located close to the heat storage tank. The power generating and hot water supply system according to claim 1 , wherein the heat storage tank is located below the fuel cell module. The power generating and hot water supply system according to claim 1 , further comprising a support for supporting the heat storage tank at a determined position relative to the fuel cell module. The power generating and hot water supply system according to claim 7 , wherein the support portion is a part of a housing that houses the fuel cell module, the heat storage tank, and the hot water heater. A fuel cell module;
a heat storage tank for storing a heat medium for heat exchange with the exhaust gas of the fuel cell module;
a water heater that is arranged alongside the fuel cell module in a direction perpendicular to the up-down direction and is capable of supplying hot water by using a heat medium stored in the heat storage tank;
A power generating and hot water supply system, wherein a portion of a gas supply path that supplies gas to the fuel cell module and the hot water heater is located adjacent to the heat storage tank. A fuel cell module;
a heat storage tank for storing a heat medium for heat exchange with the exhaust gas of the fuel cell module;
a water heater that is arranged alongside the fuel cell module in a direction perpendicular to the up-down direction and is capable of supplying hot water by using a heat medium stored in the heat storage tank;
The heat storage tank is located below the fuel cell module. A fuel cell module;
a heat storage tank for storing a heat medium for heat exchange with the exhaust gas of the fuel cell module;
a water heater that is arranged to be aligned with the fuel cell module in a direction perpendicular to the up-down direction and is capable of supplying hot water by using the heat medium stored in the heat storage tank;
a water tank for storing water to be used in a steam reforming reaction for generating fuel to be used in the fuel cell module;
The water tank is located adjacent to the thermal storage tank.

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