JP6979833B2 - Power generation system - Google Patents

Description

The present invention can be interconnected with a power system, and power can be generated from at least one of a fuel cell device, a power system, and a fuel cell device, which can generate electricity by using hydrogen obtained by reforming a raw material fuel gas containing hydrocarbons. It is equipped with a power load device that receives the supply of the fuel and a control device that controls the operation of the fuel cell device. Regarding the power generation system to determine.

Patent Document 1 describes an in-house power generation means provided so that electric power can be reverse-flowed to a commercial power system, and energy information acquisition for acquiring energy information on the commercial power system side and energy information on the in-house power generation means side. A system including means and control means for operating and controlling the private power generation means to the most economically advantageous operation mode based on the information acquired by the energy information acquisition means is described. Examples of private power generation means include a combination of a generator and an engine, and a fuel cell.

In the system described in Patent Document 1, the operation mode determining device (17) is most economically advantageous for the system by comparing the power purchase unit price, the power sale unit price, and the power generation unit price, which change every moment depending on the time zone, the season, and the like. Determine the operation mode for driving under various conditions. Then, this determination command is given to the controller (13). The controller (13) controls the operation of the private power generation means and the switching control of the circuit according to the determination command. For example, the private power generation means can be switched to a state of stopping, a state of operating at the maximum capacity, a state of making the power generation output follow the load power, and the like. Further, the connection state of the electric circuit between the load, the private power generation means, and the commercial power system is switched by the opening / closing control of the switch (6, 10, 12). As a result, the generator (2) is stopped and all the power required for the load (7, 8, 9) is purchased from the commercial power supply system (11), and the surplus power of the generator (2) is purchased. It is possible to switch between the operation of selling the electric power and the operation of supplying all the electric power required for the load (7, 8, 9) with the output of the generator (2).
Patent Document 1 describes the gas energy cost required for operating the private power generation means as the power generation unit price of the private power generation system.

Japanese Unexamined Patent Publication No. 10-42472

The power generation efficiency of the fuel cell device is not the same for all generated powers. For example, the power generation efficiency increases as the generated power increases.
Therefore, when the load power of the power load device is relatively small, if the fuel cell device tries to generate electricity equal to the load power (that is, if the load is followed), the generated power of the fuel cell is relative. It must be made smaller (that is, the power generation efficiency becomes lower). As a result, the unit price of power generation of the fuel cell device becomes relatively large.
When the load power of the power load device is relatively small, the fuel cell device can generate electric power larger than the load power. In this case, the total cost required for power generation in the fuel cell device is higher than in the case where the generated power of the fuel cell device is made to follow the load, but the power generation unit price becomes smaller as the power generation efficiency increases, and the surplus You will be able to sell electricity. Therefore, there is a possibility that the economy will be improved as compared with the case where the generated power of the fuel cell device is made to follow the load.

In this way, the period when the load power of the power load device is relatively small is economical in consideration of the load power of the power load device, the power generation power and the power generation unit price of the fuel cell, the surplus power and the power sale unit price, and the like. It can be said that it is a preferable time to verify how the fuel cell device is operated to improve.

On the other hand, when the load power of the power load device is relatively large, if all of the load power is to be covered by the generated power of the fuel cell device, the generated power of the fuel cell device becomes large and the total required for power generation is increased. Although the cost increases, it is possible to supply electric power having a relatively low unit price of power generation to the power load device as the power generation efficiency increases. That is, when the load power of the power load device is relatively large, the total cost required for power generation when the load follow-up operation is performed and, for example, the maximum power generation power is used to generate power, and if surplus power is generated, that power is used. It is considered that there will be no big difference from the total cost of selling electricity. As a result, the period when the load power of the power load device is relatively large is economical in consideration of the load power of the power load device, the power generated by the fuel cell and the unit price of power generation, the surplus power and the unit price of power sold. It can be said that the improvement is in the period when there is little need to verify how the fuel cell device is operated.

As described above, Patent Document 1 describes that the economic efficiency is improved even though there are times when it is necessary to verify how the fuel cell device is operated and there are times when it is high. In this system, the ever-changing unit price of electricity purchased, unit price of electricity, and unit price of power generation are constantly compared to determine the operation mode for operating the system under the most economically advantageous conditions, and instantly as needed. In addition, it is necessary to switch the operation of the private power generation means and switch the circuit. For example, every time the power unit price (power purchase unit price) of the commercial power system or the power generation unit price (gas energy cost) of the private power generation system is changed, the private power generation means may be changed from the stopped state to the operating state, or from the operating state. It may be necessary to suddenly change to a stopped state.

Furthermore, it is necessary to determine at any time what state the operating state of the private power generation means and the switching state of the circuit should be at a completely unpredictable timing, and the start / stop / power generation change of the private power generation means according to the decision. Although it is necessary to do it instantly, when the system is actually operated, there is a possibility that the determination between the operating state of the private power generation means and the switching state of the circuit may be delayed in time, and the generated power of the private power generation means. May not be instantly set to the desired value. In particular, when a fuel cell device that generates electricity by using hydrogen obtained by reforming a raw fuel gas containing hydrocarbons is used as a private power generation means, hydrogen can be instantaneously generated even if the supply amount of the raw fuel gas is changed. There are problems such as the problem that the amount of production is not changed (the generated power is not changed) and the problem that the fuel cell device cannot be started and stopped instantly.

The present invention has been made in view of the above problems, and an object thereof is to determine the generated power of the fuel cell device so as to improve the economic efficiency when supplying the load power of the power load device at an appropriate timing. The point is to provide a power generation system that can be used.

The characteristic configuration of the power generation system according to the present invention for achieving the above object is a fuel cell that can be interconnected with an electric power system and generates electricity by using hydrogen obtained by reforming a raw material fuel gas containing hydrocarbons. The device includes a power load device that receives power from at least one of the power system and the fuel cell device, and a control device that controls the operation of the fuel cell device. The control device is the power load device of the power load device. It is a power generation system that determines the generated power of the fuel cell device in consideration of the economic efficiency when covering the load power.
The control device is
The first load power by the power load device in the predetermined first judgment period in one day and the second load power by the power load device in the predetermined second judgment period different from the first judgment period. in contrast to the one of the first determination period and the second determination period is set to a completion determination period after the judgment period towards the load power is small, non-economy determining determination period towards the load power is large set in the period,
Before the start of setting has been the economy determination period, selling and electricity rates by at least taking into account the time of electricity sold some of generated power of the generator charges and the fuel cell system at the time of power generation by the fuel cell device Te is the generated power of the fuel cell system in the economy determination period to a point that determine the value economy is improved in the economic efficiency determination period.

According to the above-mentioned feature configuration, the control device has a first load power by the power load device in a predetermined first judgment period in a day and a power in a predetermined second judgment period different from the first judgment period. By comparing with the second load power by the load device, the judgment period of the first judgment period and the second judgment period, whichever has the smaller load power, is set as the economic judgment period for judging the economic efficiency, and the load power is set. set uneconomic determination period is not performed determination of economic efficiency of the determination period of the larger, before the start of the set has been economics determination period, the power generation rates and fuel cell system at the time of power generation by the fuel cell system The generated power of the fuel cell device in the economic evaluation period is determined to be a value that improves the economic efficiency in the economic evaluation period, at least considering the power selling charge when selling a part of the generated electric power. In other words, the control device should verify only during the economic efficiency determination period when the load power of the power load device becomes small, that is, how the fuel cell device is operated to improve the economic efficiency. However, as described above, the generated power of the fuel cell device is determined to a value that improves the economic efficiency in the economic efficiency determination period only at a preferable time. As a result, it is not necessary to determine the generated power of the fuel cell device at any time based on economic efficiency, and to instantly start / stop the fuel cell device, change the generated power, etc. according to the decision.
Therefore, it is possible to provide a power generation system capable of determining the power generation of the fuel cell device so as to improve the economic efficiency when supplying the load power of the power load device at an appropriate timing.

Another characteristic configuration of the power generation system according to the present invention is a power generation charge information acquisition device for acquiring power generation charge information required for power generation by the fuel cell device, and selling the power generated by the fuel cell device to the power system. Equipped with a power sales charge information acquisition device that acquires power sales charge information at the time
Wherein the control device, before the start of the set has been the economy determination period, the power generation rates and the fuel cell at the time of power generation by the fuel cell system can be derived by referring to the power rate information and the power sale fee information Considering the power generation fee when selling a part of the power generated by the device, the power generated by the fuel cell device during the economic efficiency determination period is set to a value that follows the load power by the power load device. Of the case where the value is determined and the case where the value of the predetermined maximum power generation is determined, the point is to determine the one that improves the economic efficiency in the economic efficiency determination period.

With the above arrangement, control apparatus, in the case where the power generated by the fuel cell device in configured to economics determination period was determined to be a value that follows the load power by the power load device, the predetermined maximum generated power Of the cases where the value of is determined, the one whose economic efficiency is improved in the economic efficiency determination period can be determined before the start of the economic efficiency determination period. As a result, it is not necessary to determine the generated power of the fuel cell device at any time based on economic efficiency, and to instantly start / stop the fuel cell device, change the generated power, etc. according to the decision.

Yet another characteristic configuration of the power generation system according to the present invention is a power purchase charge for acquiring power purchase charge information regarding the power purchase charge when purchasing power from the power system in order to cover the load power of the power load device. The information acquisition device, the power generation charge information acquisition device that acquires the power generation charge information required for power generation by the fuel cell device, and the power sale charge information when selling the power generated by the fuel cell device to the power system are acquired. Equipped with a power sales charge information acquisition device
Wherein the control device, before the start of the set has been the economy determination period can be derived by referring to the power purchase fee information and the power rate information and the power selling charge information, the power supply from the power system Considering the power purchase fee when receiving, the power generation fee when generating power with the fuel cell device, and the power selling fee when selling a part of the generated power, the fuel cell in the economic evaluation period. The economic efficiency determination period includes the case where the power generation of the device is determined to be a value that follows the load power of the power load device, the case where the value is determined to be the predetermined maximum power generation value, and the case where the value is determined to be zero. The point is to decide which one will improve the economic efficiency.

With the above arrangement, control apparatus, in the case where the power generated by the fuel cell device in configured to economics determination period was determined to be a value that follows the load power by the power load device, the predetermined maximum generated power Of the case where the value is determined to be the value of and the case where the value is determined to be zero, the one whose economic efficiency is improved in the economic evaluation period can be determined before the start of the economic evaluation period. As a result, it is not necessary to determine the generated power of the fuel cell device at any time based on economic efficiency, and to instantly start / stop the fuel cell device, change the generated power, etc. according to the decision.

Yet another characterizing feature of the power generation system according to the present invention, the control device, before the start of the set has been the uneconomic determination period, the generated power of the fuel cell system in the non-economical determination period The point is to determine the value following the load power of the power load device or the value of the predetermined maximum generated power.

When the load power of the power load device is relatively large, the total cost required for power generation when load-following operation is performed, for example, power is generated with the maximum generated power, and if surplus power is generated, the power is sold. It is considered that there is not much difference from the total cost of electricity. As a result, the period when the load power of the power load device is relatively large is economical in consideration of the load power of the power load device, the generated power and the unit price of the fuel cell device, the surplus power, and the unit price of selling power. It can be said that the improvement is in the period when there is little need to verify how the fuel cell device is operated.
Therefore, in this characteristic configuration, the control device, before the start of uneconomic determination period is set, the generated power of the fuel cell system in a non-economical determination period, the value follows the load power by the power load device or The value of the predetermined maximum generated power is determined in advance. As a result, the fuel cell device can be operated in a state where the economic efficiency is not significantly deteriorated.

Yet another characteristic configuration of the power generation system according to the present invention includes a load power information acquisition device for acquiring information on past load power by the power load device.
The control device determines the first load power and the second load power by the power load device with reference to the information about the past load power by the power load device acquired by the load power information acquisition device. At the point.

According to the above feature configuration, the reliability of the first load power and the second load power can be improved by referring to the information about the past load power in the power load device.

It is a figure which shows the structure of the power generation system of 1st Embodiment. It is a figure which illustrates the 1st determination period and the 2nd determination period. It is a figure which shows the structure of the power generation system of 2nd Embodiment.

<First Embodiment>
The power generation system according to the first embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a power generation system. As shown in the figure, the power generation system includes a fuel cell device 10, a power load device 3, and a control device 2. The fuel cell device 10 and the power load device 3 are connected to a power line 4 connected to the power system 1. As described above, the fuel cell device 10 can be interconnected with the power system 1, and the power load device 3 is configured to receive power from at least one of the power system 1 and the fuel cell device 10. The control device 2 has a function of determining the generated power of the fuel cell device 10 in consideration of economic efficiency when supplying the load power of the power load device 3.

The fuel cell device 10 generates electricity by using hydrogen obtained by reforming a raw fuel gas containing a hydrocarbon. The operation of the fuel cell device 10 is controlled by the control device 2. In the present embodiment, the fuel cell device 10 includes a reforming unit 12 and a fuel cell unit 11. The reforming unit 12 steam reforms a raw fuel gas containing a hydrocarbon (methane or the like) such as city gas to generate a fuel gas containing hydrogen as a main component. Then, the fuel gas (hydrogen) generated in the reforming section 12 is supplied to the fuel cell section 11. The fuel cell unit 11 includes a fuel cell 11a having an anode (not shown) to which the fuel gas generated by the reforming unit 12 is supplied and a cathode (not shown) to which oxygen gas is supplied, and the fuel cell 11a thereof. It is provided with a power conversion unit 11b for converting the power generated in the above into power of a desired voltage, frequency, and phase and outputting it to the power line 4.

A power measuring instrument CT1 for measuring electric power is provided on the upstream side (power system 1 side) of the middle of the power line 4 from the location to which the fuel cell device 10 is connected. The power measuring instrument CT1 is configured by using, for example, a current transformer (instrument transformer) used for detecting the current value of electric power in the power line 4, and is a product of a predetermined voltage value (for example, 100V, 200V, etc.). From, the power value in the power line 4 can be derived. The power measuring instrument CT2 may transmit only the current value of the power on the power line 4 to the control device 2, and the control device 2 may derive the power value.

When the load power of the power load device 3 and the generated power of the fuel cell device 10 (power supplied from the fuel cell device 10 to the power line 4) are equal, the power measured by the power measuring instrument CT1 becomes zero. Therefore, when the control device 2 controls the generated power of the fuel cell device 10 to a value that follows the load power of the power load device 3, for example, the fuel cell so that the power measured by the power measuring instrument CT1 becomes zero. A power generation command may be given to the device 10. The control device 2 sets the state in which the generated power of the fuel cell device 10 is smaller than the load power of the power load device 3 by a predetermined value (that is, the power measured by the power measuring instrument CT1 becomes the predetermined value). Control may be performed so as to maintain and follow.

Further, when the load power of the power load device 3 is larger than the generated power of the fuel cell device 10, that is, when a shortage of power occurs, the power measured by the power measuring instrument CT1 becomes, for example, a positive value, and the shortage thereof. Electric power corresponding to electric power (purchased electric power) is supplied from the electric power system 1. That is, the power measuring instrument CT1 measures the purchased power.
When the load power of the power load device 3 is smaller than the generated power of the fuel cell device 10, that is, when surplus power is generated, the power measured by the power measuring instrument CT1 becomes, for example, a negative value, and the surplus power becomes The corresponding electric power (electricity sold) is supplied from the fuel cell device 10 to the electric power system 1. That is, the power measuring instrument CT1 measures the power sold.

In addition, in the power generation system of the present embodiment, the power generation charge information acquisition device 8 for acquiring the power sale charge information when selling the power generated by the fuel cell device 10 to the power system 1 and the fuel cell device 10 generate power. It is provided with a power generation charge information acquisition device 9 for acquiring power generation charge information required for the purpose.

In the case of the present embodiment, since the fuel cell device 10 generates electricity by using hydrogen obtained by reforming the raw material and fuel gas, it can be said that the charge of the raw material and fuel gas is the charge required for power generation. Therefore, the power generation charge information includes the gas unit price as the power generation unit price. For example, the control device 2 can determine the amount of money for generating the unit power, that is, the power generation unit price, by the product of the gas amount (power generation efficiency) required for the fuel cell device 10 to generate the unit power and the gas unit price. The power generation efficiency of the fuel cell device 10 is not the same for all generated powers. For example, the larger the generated power, the higher the power generation efficiency of the fuel cell device 10, and the smaller the generated power, the higher the power generation efficiency of the fuel cell device 10. Shows the characteristic that the power generation efficiency of is low. In that case, that is, the larger the generated power, the lower the power generation unit price of the fuel cell device 10, and the smaller the generated power, the higher the power generation unit price of the fuel cell device 10. Such characteristics are stored in the storage device 5, and the control device 2 reads the characteristics from the storage device 5 and uses them when determining the power generation unit price. The power generation charge information acquisition device 9 acquires information about the gas unit price from the raw fuel gas supplier via an information communication line such as the Internet. The power generation charge information acquired by the power generation charge information acquisition device 9 is transmitted to the control device 2. Further, the control device 2 can also store the power generation charge information in the storage device 5. Then, the control device 2 can derive the power generation charge when the fuel cell device 10 generates power from the product of the power generated by the fuel cell device 10 and the power generation unit price thereof.

The power selling price information acquired by the power selling price information acquisition device 8 is, for example, the power selling unit price, and the power selling price information acquisition device 8 is an electric power business that accepts the sale of electric power via an information communication line such as the Internet. Obtain information about the unit price of electricity sold from a person or the like. The power sale charge information acquired by the power sale charge information acquisition device 8 is transmitted to the control device 2. Further, the control device 2 can also store the power sale charge information in the storage device 5. Then, the control device 2 can derive a power selling charge when selling a part of the generated power of the fuel cell device 10 from the product of the power sold to the power system 1 and the unit price of the power sold.

As described above, the electric power generated by the fuel cell device 10 can be supplied to the electric power load device 3, and at least a part of the generated electric power of the fuel cell device 10 can be reverse-flowed (sold) to the electric power system 1. Therefore, when supplying power to the power load device 3, (1) the fuel cell device 10 generates power that follows the load power of the power load device 3, and the generated power is used to cover the load power. 2) Some operations such as generating power larger than the load power of the power load device 3 with the fuel cell device 10, covering the load power with the generated power, and selling the surplus power to the power system 1. A pattern is possible. However, when power is supplied from the fuel cell device 10 (that is, when power is generated), a power generation fee is incurred. When the electric power generated by the fuel cell device 10 is reversely flowed to the electric power system 1 (that is, when the electric power is sold), the electric power selling charge can be obtained. As described above, even if the load power of the power load device 3 is the same, the economic efficiency may change if the generated power of the fuel cell device 10 changes.

However, when the load power of the power load device 3 is relatively small and the fuel cell device 10 tries to generate power equal to the load power (that is, when the load is followed), the power generation of the fuel cell 11a is generated. The power must be relatively low (ie, the power generation efficiency is low). As a result, the power generation unit price of the fuel cell device 10 becomes relatively large. When the load power of the power load device 3 is relatively small, the fuel cell device 10 can generate electric power larger than the load power. In this case, the total cost required for power generation in the fuel cell device 10 is higher than in the case where the generated power of the fuel cell device 10 is made to follow the load, but the power generation unit price becomes smaller as the power generation efficiency becomes higher, and the power generation unit price becomes smaller. , You will be able to sell surplus electricity. Therefore, there is a possibility that the economy will be improved as compared with the case where the generated power of the fuel cell device 10 is made to follow the load.
In this way, the period when the load power of the power load device 3 is relatively small takes into consideration the load power of the power load device 3, the power generation power and the power generation unit price of the fuel cell 11a, the surplus power, the power sale unit price, and the like. It can be said that it is a preferable time to verify how the fuel cell device 10 is operated to improve the economic efficiency.

On the other hand, when the load power of the power load device 3 is relatively large, if all of the load power is to be covered by the power generated by the fuel cell device 10, the power generated by the fuel cell device 10 becomes large, resulting in power generation. Although the total cost required is large, it is possible to supply the power load device 3 with electric power having a relatively small unit price of power generation. That is, when the load power of the power load device 3 is relatively large, the power generation unit price of the fuel cell device 10 when the load follow-up operation is performed and the rated power generation power are performed, and if surplus power is generated, that power is used. Since it is considered that there is not a large difference in the power generation unit price of the fuel cell 11a when selling power, it is more economical than the case where the load power of the power load device 3 as described above is relatively small. There is little need to verify how the fuel cell device 10 is operated.

Therefore, in the present embodiment, the control device 2 has a first load power by the power load device 3 in a predetermined first determination period in one day and a predetermined second determination period different from the first determination period. In comparison with the second load power by the power load device 3, the judgment period of the smaller load power is set as the economic judgment period for judging the economic efficiency, and the judgment period of the larger load power is the economical. Before the start of the first process set in the non-economical determination period in which the determination is not made and the economic efficiency determination period set in the first process, the power generation charge when the fuel cell device 10 generates electricity and the fuel cell device 10 The power generated by the fuel cell device 10 in the economic evaluation period is determined to be a value that improves the economic efficiency in the economic evaluation period, at least considering the power selling charge when selling a part of the generated power. 2 Processing is performed.

[First process]
FIG. 2 is a diagram illustrating the first determination period and the second determination period in one day. In the present embodiment, the first determination period is 9 hours from 3:00 to 12:00, and the second determination period is 9 hours from 15:00 to 24:00. That is, the first determination period mainly includes the daytime, and the second determination period mainly includes the nighttime. Then, in the first process described above, the control device 2 compares the first load power by the power load device 3 in the first determination period with the second load power by the power load device 3 in the second determination period. For example, the control device 2 performs the first process at a time that does not belong to either the first determination period or the second determination period (for example, at 1 o'clock), and then the first determination period and the second determination that arrive next. It is determined which of the periods is set as the economic judgment period and which is set as the non-economic judgment period. The control device 2 may periodically perform the first process at an appropriate timing. For example, the control device 2 can perform the first processing at an appropriate timing such as once a day, once every two weeks, or once a month.

In the present embodiment, the power generation system includes a load power information acquisition device 6 that acquires information about past load power by the power load device 3. Information about the electric power measured by the electric power measuring instrument CT2 is transmitted to the load electric power information acquisition device 6. The power measuring instrument CT2 is provided in the middle of the power line 4 and measures the power supplied to the power load device 3. The power measuring instrument CT2 is configured by using, for example, a current transformer (instrument transformer) used for detecting the current value of electric power in the power line 4, and is a product of a predetermined voltage value (for example, 100V, 200V, etc.). From, the power value in the power line 4 can be derived. The power measuring instrument CT2 may transmit only the current value of the power on the power line 4 to the load power information acquisition device 6, and the load power information acquisition device 6 may derive the power value.

The information acquired by the load power information acquisition device 6 as described above is transmitted to the control device 2 and stored in the storage device 5. Then, the control device 2 refers to the information about the past load power by the power load device 3 acquired by the load power information acquisition device 6, and the first load power and the first load power in the first determination period by the power load device 3. 2 Determine the second load power in the determination period. In this way, by referring to the information about the past load power in the power load device 3, the reliability of the first load power and the second load power can be improved. For example, the control device 2 has the average load power of the first determination period (for example, 9 hours between 3:00 and 12:00) and the second determination period (for example, 15:00 to 24) in the day in the past week. Contrast with the average load power (9 hours between hours). Then, the control device 2 sets the determination period with the smaller load power as the economic efficiency determination period for determining the economic efficiency, and sets the determination period with the larger load power as the uneconomical determination period without determining the economic efficiency. Set to the period. Therefore, in the present embodiment, if the first judgment period is larger than the second judgment period, the user stays in the daytime at a facility such as a house or a business establishment where a power generation system is installed. It can be said that. On the other hand, if the second determination period is larger than the first determination period, it can be said that the user is a night stay type who stays at a facility provided with a power generation system at night.

[Second process]
In the second process, the control device 2 generates power when the fuel cell device 10 that can derive power by referring to the power generation charge information and the power sale charge information before the start of the economic efficiency determination period set in the first process. Considering the charge and the power generation charge when selling a part of the generated power of the fuel cell device 10, the generated power of the fuel cell device 10 in the economic evaluation period is changed to the load power of the power load device 3. Of the case where the value is determined to follow and the case where the value is determined to be the predetermined maximum power generation value, it is determined which one is more economical in the economic efficiency determination period. Here, the control device 2 can derive the power generation charge when the fuel cell device 10 generates power from the product of the power generated by the fuel cell device 10 and the power generation unit price thereof, and the power sold to the power system 1 and the power sold thereof. From the product with the unit price, it is possible to derive the power selling charge when selling a part of the generated power of the fuel cell device 10.

Then, when the control device 2 refers to the power sale charge information transmitted from the power sale charge information acquisition device 8 and the power generation charge information transmitted from the power generation charge information acquisition device 9, the fuel cell device 10 generates power. Considering the power generation charge and the power generation charge when selling a part of the generated power, the generated power of the fuel cell device 10 during the economic efficiency determination period is set to a value that follows the load power of the power load device 3. It is possible to derive the economic efficiency when the determination is made and the economic efficiency when the value of the predetermined maximum power generation is determined. Then, the control device 2 determines the generated power of the fuel cell device 10 in the economic efficiency determination period to a value that improves the economic efficiency in the economic efficiency determination period.

When the control device 2 determines the generated power of the fuel cell device 10 in the economic efficiency determination period to a value that follows the load power of the power load device 3, for example, the power measured by the power measuring instrument CT1 becomes zero. Gives a power generation command to the fuel cell device 10.
On the other hand, when the control device 2 determines the power generation power of the fuel cell device 10 in the economical efficiency determination period to the value of the predetermined maximum power generation power, the power generation power of the fuel cell device 10 becomes the maximum power generation power. Gives a power generation command to the fuel cell device 10.

As described above, the control device 2 is limited to the economic efficiency determination period in which the load power of the power load device 3 becomes small, that is, the economic efficiency is improved when the fuel cell device 10 is operated. The second process is performed only at a time when it is preferable to verify the existence. As a result, it is not necessary to determine the generated power of the fuel cell device 10 at any time based on economic efficiency, and to instantly start / stop the fuel cell device 10 or change the generated power according to the determination. Therefore, it is possible to provide a power generation system capable of determining the generated power of the fuel cell device 10 so as to improve the economic efficiency when supplying the load power of the power load device 3 at an appropriate timing.

Further, in the uneconomical determination period set in the first process, that is, in the period when the load power of the power load device 3 is relatively large, power generation is required when the fuel cell device 10 performs the load follow-up operation. It is considered that there is not a great difference between the total cost and, for example, the total cost when the fuel cell device 10 generates power with the maximum generated power and the surplus power is generated and the power is sold. As a result, the time when the load power of the power load device 3 is relatively large takes into consideration the load power of the power load device 3, the generated power and the unit price of the fuel cell device 10, the surplus power, the unit price of selling power, and the like. It can be said that the economic efficiency is improved at a time when it is not necessary to verify how the fuel cell device 10 is operated.
Therefore, in the present embodiment, in the second process, the control device 2 uses the generated power of the fuel cell device 10 in the uneconomical determination period before the start of the uneconomical determination period set in the first process. It is determined to be a value following the load power of the load device 3 or a predetermined maximum power generation power value. Then, the control device 2 generates power to the fuel cell device 10 so that, for example, the power measured by the power measuring device CT1 becomes zero, or the generated power of the fuel cell device 10 becomes the maximum generated power thereof. Give a command. As a result, the fuel cell device 10 can be operated in a state where the economic efficiency is not significantly deteriorated.

<Second Embodiment>
The power generation system of the second embodiment is different from the above-described embodiment in that the economic efficiency is determined in consideration of the purchase price of the electric power supplied from the electric power system. The power generation system of the second embodiment will be described below, but the description of the same configuration as that of the above embodiment will be omitted.

FIG. 3 is a diagram showing the configuration of the power generation system of the second embodiment.
The power generation system of the present embodiment includes a power purchase charge information acquisition device 7 for acquiring power purchase charge information regarding the power purchase power when purchasing power from the power system 1 in order to cover the load power of the power load device 3. ing. This power purchase charge information is, for example, the above-mentioned power purchase unit price, and the power purchase charge information acquisition device 7 is a business operator (for example, an electric power company, etc.) that supplies power to the power system 1 via an information communication line such as the Internet. ) To obtain information about the unit price of electricity purchased. The power purchase charge information acquired by the power purchase charge information acquisition device 7 is transmitted to the control device 2. Further, the control device 2 can also store the power purchase charge information in the storage device 5. Then, the control device 2 can derive the power purchase charge when receiving the power supply from the power system 1 from the product of the power purchased from the power system 1 and the unit price of the power purchased.

Since there are two power sources for supplying electric power to the electric power load device 3, the electric power system 1 and the fuel cell device 10, the electric power load device 3 can receive electric power from both the electric power system 1 and the fuel cell device 10. .. Therefore, when supplying power to the power load device 3, (1) the generated power of the fuel cell device 10 is set to zero, and all the load power of the power load device 3 is covered by the power purchased from the power system 1. That, (2) power equal to the load power of the power load device 3 is generated by the fuel cell device 10, and the load power is covered by the generated power, (3) power larger than the load power of the power load device 3 is used as fuel. Several operation patterns are conceivable, such as generating power with the battery device 10, covering the load power with the generated power, and selling the surplus power to the power system 1. However, when power is supplied from the power system 1 (that is, when power is purchased), a power purchase fee is incurred, and when power is supplied from the fuel cell device 10 (that is, power generation is performed). In that case), a power generation fee will be incurred. When the electric power generated by the fuel cell device 10 is reversely flowed to the electric power system 1 (that is, when the electric power is sold), the electric power selling charge can be obtained. As described above, even if the load power of the power load device 3 is the same, the economic efficiency may change if the generated power of the fuel cell device 10 changes.

Then, in the second process, the control device 2 can derive the power system by referring to the power purchase charge information, the power generation charge information, and the power sale charge information before the start of the economic efficiency determination period set in the first process. Economical judgment period in consideration of the power purchase fee when receiving power supply from 1 and the power generation fee when generating power with the fuel cell device 10 and the power selling fee when selling a part of the generated power. When the power generation of the fuel cell device 10 in the above is determined to be a value that follows the load power of the power load device 3, the value of the predetermined maximum power generation is determined, or the value is determined to be zero. Decide which one will improve the economic efficiency during the economic efficiency judgment period.

<Another Embodiment>
<1>
In the above embodiment, the configuration of the power generation system has been described with specific examples, but the configuration can be changed as appropriate.
For example, in the above embodiment, the example in which the control device 2 is separate from the fuel cell device 10 and the like has been described, but the control device 2 may also be used as a control unit provided inside the fuel cell device 10. ..

<2>
In the above embodiment, the first determination period and the second determination period have been described with specific examples, but their lengths and timings can be changed as appropriate. Further, in the above embodiment, the case where the first determination period and the second determination period do not overlap each other in time has been described, but the first determination period and the second determination period may partially overlap in time.

<3>
The configurations disclosed in the above embodiment (including other embodiments, the same shall apply hereinafter) can be applied in combination with the configurations disclosed in other embodiments as long as there is no contradiction, and are also disclosed herein. The embodiment is an example, and the embodiment of the present invention is not limited to this, and can be appropriately modified without departing from the object of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be used for a power generation system capable of determining the power generation of a fuel cell device so as to improve the economic efficiency when supplying the load power of the power load device at an appropriate timing.

1 Power system 2 Control device 3 Power load device 4 Power line 5 Storage device 6 Load power information acquisition device 7 Power purchase charge information acquisition device 8 Power sale charge information acquisition device 9 Power generation charge information acquisition device 10 Fuel cell device 11 Fuel cell unit 11a Fuel cell 11b Power conversion unit 12 Remodeling unit CT1 Power measurement unit CT2 Power measurement unit

Claims (5)

A fuel cell device that can be interconnected with the power system and generates electricity using hydrogen obtained by reforming raw fuel gas containing hydrocarbons.
A power load device that receives power from at least one of the power system and the fuel cell device, and
A control device for controlling the operation of the fuel cell device is provided.
The control device is a power generation system that determines the generated power of the fuel cell device in consideration of economic efficiency when supplying the load power of the power load device.
The control device is
The first load power by the power load device in the predetermined first judgment period in one day and the second load power by the power load device in the predetermined second judgment period different from the first judgment period. in contrast to the one of the first determination period and the second determination period is set to a completion determination period after the judgment period towards the load power is small, non-economy determining determination period towards the load power is large set in the period,
Before the start of setting has been the economy determination period, selling and electricity rates by at least taking into account the time of electricity sold some of generated power of the generator charges and the fuel cell system at the time of power generation by the fuel cell device Te, power generation systems that determine the fuel the value economy is improved electric power generated in the economics determination period of the battery device in the economics determination period. A power generation charge information acquisition device that acquires power generation charge information required for power generation by the fuel cell device, and a power generation charge information acquisition device.
It is equipped with a power selling price information acquisition device for acquiring power selling price information when selling the power generated by the fuel cell device to the power system.
Wherein the control device, before the start of the set has been the economy determination period, the power generation rates and the fuel cell at the time of power generation by the fuel cell system can be derived by referring to the power rate information and the power sale fee information Considering the power generation fee when selling a part of the power generated by the device, the power generated by the fuel cell device during the economic efficiency determination period is set to a value that follows the load power by the power load device. The power generation system according to claim 1, wherein the power generation system is determined according to the case where the value is determined and the case where the value of the predetermined maximum power generation is determined, whichever is better in the economic efficiency determination period. A power purchase charge information acquisition device for acquiring power purchase charge information for power purchase power when purchasing power from the power system in order to cover the load power of the power load device, and a power purchase charge information acquisition device.
A power generation charge information acquisition device that acquires power generation charge information required for power generation by the fuel cell device, and a power generation charge information acquisition device.
It is equipped with a power selling price information acquisition device for acquiring power selling price information when selling the power generated by the fuel cell device to the power system.
Wherein the control device, before the start of the set has been the economy determination period can be derived by referring to the power purchase fee information and the power rate information and the power selling charge information, the power supply from the power system Considering the power purchase fee when receiving, the power generation fee when generating power with the fuel cell device, and the power selling fee when selling a part of the generated power, the fuel cell in the economic evaluation period. The economic efficiency determination period includes the case where the power generation of the device is determined to be a value that follows the load power of the power load device, the case where the value is determined to be the predetermined maximum power generation value, and the case where the value is determined to be zero. The power generation system according to claim 1, wherein the power generation system is determined to be more economical. Wherein the control device, before the start of the set have been the non-economical determination period, the generated power of the fuel cell device of the non-economical determination period, the value follows the load power by the power load device or predetermined The power generation system according to any one of claims 1 to 3, which is determined by the value of the maximum generated power of. A load power information acquisition device for acquiring information on past load power by the power load device is provided.
The control device determines the first load power and the second load power by the power load device with reference to the information about the past load power by the power load device acquired by the load power information acquisition device. The power generation system according to any one of claims 1 to 4.

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