JP2007257972A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system with a total energy utilization efficiency improved. <P>SOLUTION: The system is provided with a plurality of power generating devices 3 each equipped with a fuel cell 9 generating power by electrochemical reaction between fuel gas and oxidizing gas, and a reformer producing fuel gas supplied to toe the fuel cell 9 with the use of exhaust heat of the latter 9. Each power generating device 3, 3 and a fuel gas station 20 share surplus fuel gas against fuel gas needed for generation of the fuel cell 9 out of the fuel gas produced at the reformer 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cell system including a fuel cell that generates electric power by a reaction between an oxidizing gas and a fuel gas.

In recent years, a fuel cell system using a fuel cell that generates power by an electrochemical reaction between an oxidizing gas and a fuel gas as an energy source has attracted attention. In such a fuel cell system, there is a technique for sharing hydrogen as fuel gas, exhaust heat, and electric power among a plurality of facilities (convenience store, general household, power plant, hydrogen station, etc.) (see, for example, Patent Document 1). . In this technology, hydrogen is hydrogen, exhaust heat is exhaust heat, and electric power is electric power.
JP 2004-355838 A

  In the case of the above-described technology, energy loss is particularly large when waste heat is shared between facilities, and the energy cannot be effectively utilized as a whole.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a fuel cell system capable of improving the overall energy utilization efficiency.

  In order to achieve the above object, a fuel cell system according to the present invention supplies a fuel cell that generates power by an electrochemical reaction between a fuel gas and an oxidizing gas, and supplies the fuel cell using exhaust heat of the fuel cell. A plurality of power generation equipment having a reformer that generates fuel gas, and surplus fuel gas with respect to the fuel gas required for power generation of the fuel cell among the fuel gas generated by the reformer in each power generation equipment, Sharing between the power generation facilities or between the power generation facility and other facilities.

  Further, the gas sharing method in the fuel cell system according to the present invention is supplied to the fuel cell using the fuel cell that generates power by the electrochemical reaction between the fuel gas and the oxidizing gas, and the exhaust heat of the fuel cell. A gas sharing method in a fuel cell system comprising a plurality of power generation equipment having a reformer that generates fuel gas, wherein the fuel cell is a fuel gas generated by the reformer in each power generation equipment. The surplus fuel gas for the fuel gas required for power generation is shared between the power generation facilities or between the power generation facilities and other facilities.

  According to the above configuration, the same power generation is applied to the exhaust heat of a fuel cell having a large energy loss due to sharing between power generation facilities or between a power generation facility and another facility (hereinafter simply referred to as “between facilities”). By using it for the production | generation of the fuel gas by the reformer in an installation, the loss can be restrained small and it can utilize efficiently. Then, the surplus fuel gas is shared between the facilities for the fuel gas that is generated by the reformer by efficiently using the exhaust heat in each power generation facility in this way and is less likely to be lost even between the facilities.

  For example, a solid oxide fuel cell can be used as the fuel cell.

  According to the present invention, the overall energy utilization efficiency can be improved.

  Hereinafter, a fuel cell system according to an embodiment of the present invention will be described with reference to the drawings.

  The fuel cell system 1 according to this embodiment includes individual power generation facilities 3 at a plurality of installation locations 2, 2,... That are homes or business locations (for example, convenience stores, public baths, barber shops, restaurants, etc.). It is configured.

  Each of the power generation facilities 3, 3,... Is connected to a raw fuel storage facility 5 that stores a raw fuel made of a hydrocarbon-based fuel such as methane, and the raw fuel storage facility 5 via a pipe 6. A reformer 7 for reforming the raw fuel from the storage facility 5 into a hydrogen-rich fuel gas, and a fuel gas and an oxidant gas connected to the reformer 7 via a pipe 8 and supplied from the reformer 7 It has a stationary fuel cell 9 that generates electricity by an electrochemical reaction with certain air.

  And in each of the power generation facilities 3, 3,..., The fuel cell 9 generates power in accordance with the required power of electric devices (power consuming devices) 10 that are provided at the same installation location 2 and consume power, or Power is generated at the rated value regardless of the required power.

  Here, the fuel cell 9 is a solid oxide fuel cell (SOFC) that is used as a stationary type and has high power generation efficiency. Since this fuel cell 9 has an operating temperature as high as 700 ° C. to 1000 ° C., for example, the fuel cell 9 has a relatively high temperature during power generation and generates a large amount of heat. For this reason, the heat generated by the fuel cell 9 is used in the exhaust heat using equipment 11 such as a hot water supply equipment provided in the same installation place 2 (see arrow A in FIG. 1), and the reformer 7 is attached to the fuel cell 9. In addition, the remaining exhaust heat that is not used in the exhaust heat using equipment 11 is used for promoting the reforming reaction of the reformer 7 entirely (see arrow B in FIG. 1).

  A branch pipe 14 branches from a pipe 8 connecting the reformer 7 and the fuel cell 9 of each of the plurality of power generation facilities 3, 3,..., And the branch pipes 14, 14,. Are connected to a common pipe 15 that connects the plurality of power generation facilities 3, 3,.

  Further, in each of the plurality of power generation facilities 3, 3,..., A distributor that appropriately distributes the fuel gas from the reformer 7 to the fuel cell 9 and the branch pipe 14 at the branch position of the branch pipe 14 in the pipe 8. 17 is provided. Further, in each of the power generation facilities 3, 3,..., A control device 18 that controls the distributor 17 in accordance with the state of the fuel cell 9 and the electrical equipment 10 is provided.

  In addition to the plurality of power generation facilities 3, 3,..., A fuel gas station (another facility) 20 is connected to the common pipe 15 through a pipe 21.

  The fuel gas station 20 is connected to a pipe 21 and has a gas tank 22 for storing the fuel gas, and a fuel cell traveling for driving the fuel gas stored in the gas tank 22 by driving an electric motor by power generation of the fuel cell. And a gas supply device 24 that supplies the vehicle 23 to the vehicle-mounted tank 23a of the vehicle 23 such as a fuel gas traveling vehicle that travels with the driving force of the internal combustion engine that burns the vehicle and fuel gas.

  In each of the power generation facilities 3, 3,..., The control device 18 reforms the raw fuel stored in the raw fuel storage facility 5 with the reformer 7, and generates fuel gas. The fuel cell 9 is caused to generate power according to the required power of the electrical equipment 10 provided in the same installation place 2 or at a rated power, but the exhaust heat of the fuel cell 9 generated at that time is reduced. If necessary, the exhaust heat using equipment 11 provided in the same installation place 2 is used, and the remaining exhaust heat is used to promote the reforming reaction by the attached reformer 7, that is, the generation of the fuel gas. become.

  At this time, the fuel gas generated by the reformer 7 may require less fuel gas to generate the required power by the fuel cell 9 of the same power generation facility 3. In the mass device 7, the exhaust heat of the fuel cell 9 other than that used for the exhaust heat using equipment 11 is fully utilized for the reforming reaction, and the fuel gas is continuously generated to the maximum extent.

  Then, the control device 18 controls the distributor 17 to send only the fuel gas required for power generation of the required power by the fuel cell 9 among the reformed fuel gas to the fuel cell 9 and the remaining surplus fuel gas. Then, the gas is sent from the branch pipe 14 to the common pipe 15 and stored in the gas tank 22 of the adjacent fuel gas station 20, for example. That is, the surplus fuel gas is shared between the power generation facility 3 and the fuel gas station 20 which is another facility.

  Then, the vehicle 23 that receives the supply of the fuel gas from the fuel gas station 20 receives the supply of the fuel gas containing the surplus fuel gas described above. That is, surplus fuel gas in the power generation facility 3 is also shared by the plurality of vehicles 23 via the fuel gas station 20.

  In addition, for example, when the power generation fuel gas supplied to the fuel cell 9 is insufficient in another power generation facility 3 due to a shortage of raw fuel in the raw fuel storage facility 5, this power generation facility The surplus fuel gas is supplied to the power generation equipment 3 through the common pipe 15 and the branch pipe 14 by controlling the third distributor 17.

  According to the fuel cell system 1 according to the present embodiment described above, in each of the plurality of power generation facilities 3, 3,..., The exhaust heat of the fuel cell 9 having a large energy loss due to sharing between facilities is the same. By using it for the production of fuel gas by the reformer 7 in the facility, the loss can be suppressed to a low level and it can be used efficiently.

  As described above, when the exhaust heat generated at the time of power generation of the fuel cell 9 is used as energy necessary for the reforming reaction, the reforming efficiency of the fuel gas increases to nearly 100% with respect to 60% when not used. . Then, with respect to the fuel gas that is generated by the reformer 7 using the exhaust heat efficiently in each of the power generation facilities 3, 3,. , And the power generation facilities 3, 3... And the fuel gas station 20.

  Therefore, the overall energy utilization efficiency can be improved. That is, it becomes a highly efficient system in the energy flow using hydrocarbon fuel as the starting raw fuel, which leads to reduction of temporary energy consumption and reduction of carbon dioxide generation.

  The above-described power generation equipment 3 includes, for example, a centralized power generation facility that concentrates power generation for each dwelling unit at one place in an apartment house or the like. The fuel cell 9 and the large reformer 7 are installed, reforming is performed by the reformer 7 by the exhaust heat of power generation, and surplus fuel gas is sent to other equipment such as the fuel gas station 20.

  Moreover, in the said embodiment, although the raw fuel storage facility 5 is mentioned as an example as a raw fuel supply source, it is not restricted to such a storage facility, For example, it is also possible to use pipelines, such as city gas.

1 is a configuration diagram of a fuel cell system according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Fuel cell system, 3 ... Power generation equipment (other equipment), 7 ... Reformer, 9 ... Fuel cell, 10 ... Electric equipment (electric power consumption apparatus), 20 ... Fuel gas station (equipment).

Claims (3)

A plurality of power generation facilities having a fuel cell that generates power by an electrochemical reaction between a fuel gas and an oxidizing gas, and a reformer that generates fuel gas to be supplied to the fuel cell using exhaust heat of the fuel cell Prepared,
Of the fuel gas generated by the reformer in each power generation facility, surplus fuel gas for the fuel gas required for power generation of the fuel cell is shared between the power generation facilities or between the power generation facility and other facilities. Fuel cell system.   The fuel cell system according to claim 1, wherein the fuel cell is a solid oxide fuel cell. A plurality of power generation facilities having a fuel cell that generates power by an electrochemical reaction between a fuel gas and an oxidizing gas, and a reformer that generates fuel gas to be supplied to the fuel cell using exhaust heat of the fuel cell A gas sharing method in a fuel cell system comprising:
Of the fuel gas generated by the reformer in each power generation facility, surplus fuel gas for the fuel gas required for power generation of the fuel cell is shared between the power generation facilities or between the power generation facility and other facilities. Gas sharing method in a fuel cell system.

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