Operation plan creation device, operation plan creation method, and computer program

Abstract

According to the present invention, when a total hydrogen supply initial prediction amount exceeds a total hydrogen demand prediction amount, an operation plan creation device calculates time series data for a hydrogen demand cumulative plan amount such that, for an entire calculation period of an operation plan period, the hydrogen demand cumulative plan amount is below a first addition amount obtained by adding a total for an initial prediction amount for a hydrogen production amount to a hydrogen remainder amount for a tank, and when the total hydrogen supply initial prediction amount does not exceed the total hydrogen demand prediction amount, the operation plan creation device calculates time series data for the hydrogen demand cumulative plan amount such that, for the entire calculation period of the operation plan period, the hydrogen demand cumulative plan amount is below a second addition amount obtained by adding the first addition amount and a total for a prediction amount for an additional production amount for hydrogen from additional power.

Description

Operation plan creation device, operation plan creation method, and computer program

[0001] The present invention relates to an operation plan creation device, an operation plan creation method, and a computer program.

[0002] To achieve a carbon-neutral, decarbonized society, it is expected that the use of variable renewable energy (VRE), such as solar and wind power whose output is dependent on the weather, will become increasingly widespread in the future. One possible way to utilize VRE is to produce hydrogen using VRE, store the produced hydrogen at least temporarily, and use that hydrogen in downstream processes.

[0003] Patent Document 1 describes an electrolysis system. The electrolysis system includes a power generation device, a power distribution device, an electrolysis device, and a booster device. The power generation device generates electricity using renewable energy. The power distribution device distributes the generated electricity. The electrolysis device electrolyzes water using the distributed electricity. The booster device uses the distributed electricity (surplus electricity exceeding the power consumption of the electrolysis device) to boost the pressure of hydrogen and oxygen produced by the electrolysis device.

[0004] Japanese Patent Application Laid-Open No. 2019-026858

[0005] The challenge is to create an operation plan for a chemical plant that produces chemical products such as ammonia using hydrogen produced by a hydrogen production device that uses electricity generated using renewable energy.

[0006] An object of the present invention is to provide an operation plan creation device, an operation plan creation method, and a computer program that can create an operation plan for a chemical plant that produces chemical products using hydrogen produced by a hydrogen production device that uses electricity generated using renewable energy as a raw material.

[0007] One aspect of the present invention is an operation plan creation device that creates an operation plan for a chemical plant that includes a hydrogen production device that produces hydrogen using electricity generated using renewable energy, a chemical production device that produces chemical products using hydrogen produced by the hydrogen production device as a raw material, and an intermediate tank that is provided between the hydrogen production device and the chemical production device and that stores hydrogen produced by the hydrogen production device as a buffer. The operation plan creation device includes an acquisition unit that acquires first time series data of an initial total hydrogen supply forecast amount that is an initial forecast amount of a total hydrogen supply amount for an operation plan period, a total hydrogen demand forecast amount that is a forecast amount of a total hydrogen demand for the operation plan period, and a first addition amount that is a cumulative sum of an initial forecast amount of hydrogen production by the hydrogen production device for the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period, and a time series data of a first addition amount that is a cumulative sum of an initial forecast amount of hydrogen production by the hydrogen production device for the operation plan period. and if the initial forecasted total hydrogen supply amount exceeds the forecasted total hydrogen demand amount, calculates time series data of the cumulative planned hydrogen demand amount so that the cumulative planned hydrogen demand amount, which is a cumulative planned amount of hydrogen demand for the chemical production apparatus during the operation planning period, falls below the first additional amount over all calculation periods of the operation planning period; and if the initial forecasted total hydrogen supply amount does not exceed the forecasted total hydrogen demand amount, acquires second time series data of a cumulative predicted amount of additional hydrogen to be produced by the hydrogen production apparatus using additional electricity, and calculates time series data of the cumulative planned hydrogen demand amount so that the cumulative planned hydrogen demand amount falls below a second additional amount obtained by adding the first additional amount of the first time series data and the cumulative total of the second time series data over all calculation periods of the operation planning period.One aspect of the present invention is an operation plan creation device in which, in the above-mentioned operation plan creation device, the planning unit calculates time series data of the cumulative planned amount of hydrogen demand so as to maximize the sum of the differences between the first additional amount and the cumulative planned amount of hydrogen demand for each calculation period of the operation plan when the total hydrogen supply initial forecast amount exceeds the total hydrogen demand forecast amount, and on the other hand, calculates time series data of the cumulative planned amount of hydrogen demand so as to maximize the sum of the differences between the second additional amount and the cumulative planned amount of hydrogen demand for each calculation period of the operation plan when the total hydrogen supply initial forecast amount does not exceed the total hydrogen demand forecast amount. In one aspect of the present invention, the chemical plant further includes a product tank for storing hydrogen produced by the hydrogen production apparatus for shipment, the first additional amount is a sum of the remaining amounts of hydrogen in the intermediate tank and the product tank at the start of the operation plan period and an accumulated initial predicted amount of hydrogen production by the hydrogen production apparatus for the operation plan period, the cumulative planned hydrogen demand amount is a sum of the planned hydrogen shipment amount for the operation plan period and a planned cumulative hydrogen demand amount as a raw material for the chemical production apparatus for the operation plan period, and a constraint for calculating the time series data of the cumulative planned hydrogen demand amount is added such that the remaining amount of hydrogen in the product tank on a hydrogen shipment date for the operation plan period is equal to or greater than the planned shipment amount.

[0008] One aspect of the present invention is an operation plan creation method for creating an operation plan for a chemical plant including a hydrogen production apparatus that produces hydrogen using electricity generated using renewable energy, a chemical production apparatus that produces chemical products using hydrogen produced by the hydrogen production apparatus as a raw material, and an intermediate tank that is provided between the hydrogen production apparatus and the chemical production apparatus and that stores hydrogen produced by the hydrogen production apparatus as a buffer, the operation plan creation method comprising the steps of: a first step of acquiring an initial total hydrogen supply forecast that is an initial forecast amount of a total hydrogen supply amount for an operation plan period; and a total hydrogen demand forecast that is a forecast amount of a total hydrogen demand for the operation plan period; a second step of acquiring first time series data of a first added amount obtained by adding a cumulative total of an initial forecast amount of hydrogen production by the hydrogen production apparatus for the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period; and a second step of acquiring first time series data of a first added amount obtained by adding a cumulative total of an initial forecast amount of hydrogen production by the hydrogen production apparatus for the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period. a fourth step, if the total hydrogen supply forecast amount exceeds the total hydrogen demand forecast amount, calculating time series data of the cumulative planned hydrogen demand amount so that the cumulative planned hydrogen demand amount, which is a cumulative planned amount of demand for hydrogen as a raw material for the chemical production plant during the operation planning period, falls below the first additional amount over all calculation periods of the operation planning period; and a fifth step, if the total hydrogen supply forecast amount does not exceed the total hydrogen demand forecast amount, acquiring second time series data of the cumulative predicted amount of additional hydrogen to be produced by the hydrogen production plant using additional electricity, and calculating time series data of the cumulative planned hydrogen demand amount so that the cumulative planned hydrogen demand amount falls below a second additional amount obtained by adding the first additional amount of the first time series data and the cumulative total of the second time series data over all calculation periods of the operation planning period.

[0009] In one aspect of the present invention, an operation plan creation device for creating an operation plan for a chemical plant includes a hydrogen production device that produces hydrogen using electricity generated using renewable energy, a chemical production device that produces chemical products using hydrogen produced by the hydrogen production device as a raw material, and an intermediate tank that is provided between the hydrogen production device and the chemical production device and that stores hydrogen produced by the hydrogen production device as a buffer. The operation plan creation device includes a computer that creates an operation plan for the chemical plant, the computer comprising: a first step of acquiring an initial hydrogen supply forecast, which is an initial forecast of the total supply of hydrogen for a period of the operation plan, and a total hydrogen demand forecast, which is a forecast of the total demand of hydrogen for the period of the operation plan; a second step of acquiring first time series data of a first addition, which is obtained by adding the remaining amount of hydrogen in the intermediate tank at the start of the period of the operation plan to the cumulative total of the initial forecast of the amount of hydrogen produced by the hydrogen production device for the period of the operation plan; and a second step of determining whether the initial total hydrogen supply forecast exceeds the total hydrogen demand forecast. a fourth step of calculating time series data of the cumulative planned hydrogen demand, if the initial forecasted total hydrogen supply amount exceeds the forecasted total hydrogen demand, so that the cumulative planned hydrogen demand amount, which is a cumulative planned amount of demand for hydrogen as a raw material for the chemical production apparatus during the operation planning period, falls below the first additional amount over all calculation periods of the operation planning period; and a fifth step of acquiring second time series data of the cumulative planned amount of hydrogen demand, if the initial forecasted total hydrogen supply amount does not exceed the forecasted total hydrogen demand, so that the cumulative planned hydrogen demand amount falls below a second additional amount, which is a sum of the first additional amount of the first time series data and the cumulative total of the second time series data, over all calculation periods of the operation planning period.

[0010] According to the present invention, it is possible to create an operation plan for a chemical plant that produces chemical products using hydrogen as a raw material produced by a hydrogen production device that uses electricity generated using renewable energy.

[0011] FIG. 1 is a diagram showing an example of a schematic configuration of an operation plan creation system according to an embodiment. FIG. 2 is a diagram showing an example of a schematic configuration of an operation plan creation device according to an embodiment. FIG. 3 is a flowchart showing an example of a procedure of an operation plan creation method according to an embodiment. FIG. 4 is a diagram for explaining a method for calculating time series data of a cumulative planned amount of hydrogen demand without power purchase according to an embodiment. FIG. 5 is a diagram for explaining a method for calculating time series data of a cumulative planned amount of hydrogen demand without power purchase according to an embodiment. FIG. 6 is a diagram for explaining a method for calculating time series data of a cumulative planned amount of hydrogen demand with power purchase according to an embodiment. FIG. 7 is a diagram for explaining a method for calculating time series data of a cumulative planned amount of hydrogen demand with power purchase according to an embodiment.

[0012] Next, an operation plan creation device, an operation plan creation method, and a computer program according to the present embodiment will be described with reference to the drawings. The embodiment described below is merely an example, and the embodiment to which the present invention is applied is not limited to the following embodiment. In all drawings used to describe the embodiment, the same reference numerals are used for components having the same functions, and repeated description will be omitted. In addition, "based on XX" in this application means "based on at least XX" and includes cases where the operation plan is based on another element in addition to XX. In addition, "based on XX" is not limited to cases where XX is directly used, but also includes cases where the operation plan is based on XX after calculation or processing. "XX" is an arbitrary element (for example, arbitrary information).

[0013] FIG. 1 is a diagram illustrating a schematic configuration example of an operation plan creation system 1 according to the present embodiment. In FIG. 1, the operation plan creation system 1 includes an operation plan creation device 10 and a terminal device 20. The operation plan creation device 10 and the terminal device 20 are communicatively connected to each other. For example, the operation plan creation device 10 and the terminal device 20 may be communicatively connected to each other using a communication line or a communication cable. The terminal device 20 may be, for example, a mobile communication terminal device such as a smartphone or a tablet computer (tablet PC), or may be a stationary communication terminal device (for example, a stationary personal computer). For example, the terminal device 20 may be a mobile communication terminal device such as a smartphone, and may be communicatively connected to the operation plan creation device 10 using a wireless communication line.

[0014] The operation plan creation device 10 is communicatively connected to the chemical plant 30 using a communication line so as to be able to communicate with the chemical plant 30. For example, the operation plan creation device 10 may be communicatively connected to the chemical plant 30 using a communication network such as a local area network (LAN) or the Internet.

[0015] The chemical plant 30 is a plant (production facility) that produces chemical substances (chemical products) using hydrogen produced by a hydrogen production device that uses electricity generated using renewable energy as a raw material. Examples of chemical products include ammonia, methanol, organic hydrides, methane, carbon monoxide, diesel, and hydrogen peroxide.

[0016] The chemical plant 30 includes a water electrolysis device 31, an H2 product tank 32, a compressor 33, a chemical production device 34, and an H2 intermediate tank 35. The water electrolysis device 31 is an example of a hydrogen production device that produces hydrogen. The H2 product tank 32 is a product tank that stores hydrogen produced by the water electrolysis device 31 for shipping. Hydrogen (product hydrogen) Ma is shipped as a product from the H2 product tank 32.

[0017] Of the hydrogen produced by the water electrolysis device 31, the hydrogen that is not stored in the H2 product tank 32 is pressurized by a compressor 33 and supplied to a chemical production device 34. The chemical production device 34 produces a chemical product Mb using the hydrogen produced by the water electrolysis device 31 as a raw material.

[0018] Of the hydrogen pressurized by the compressor 33 and supplied to the chemical production plant 34, hydrogen that is not immediately used as a raw material for chemical products is temporarily stored in the H2 intermediate tank 35. The H2 intermediate tank 35 is an intermediate tank that stores the hydrogen produced in the water electrolysis plant 31 as a buffer.

[0019] The water electrolysis device 31 is supplied with electric power POWa and POWb to be used in the water electrolysis device 31. Electric power POWa is electric power unique to the chemical plant 30 and is generated using only renewable energy. Electric power POWb is purchased electric power and is generated using energy that may include energy other than renewable energy. Hereinafter, electric power POWa will be referred to as unique electric power POWa, and electric power POWb will be referred to as purchased electric power POWb.

[0020] In this embodiment, the independent power POWa is power generated using variable renewable energy such as solar power, wind power, etc., as an example of renewable energy. Therefore, the independent power POWa may be affected by weather.

[0021] The operation plan creation device 10 creates an operation plan for the chemical plant 30. In this embodiment, the operation plan creation device 10 creates an operation plan for the chemical plant 30 so as to satisfy the planned shipping volumes of the hydrogen product Ma and the chemical product Mb. When a situation in which the planned shipping volumes cannot be satisfied is predicted to occur and a predetermined alert issuance condition is satisfied, the operation plan creation device 10 transmits alert information to the terminal device 20. The alert information is notified by the terminal device 20. Furthermore, when a situation in which the planned shipping volumes cannot be satisfied is predicted to occur, the operation plan creation device 10 creates an operation plan in accordance with a predetermined operation plan handling method.

[0022] 2 is a diagram showing an example of a schematic configuration of the operation plan creation device 10 according to the present embodiment. In FIG. 2, the operation plan creation device 10 includes a control unit 110, a storage unit 120, and a communication unit 130.

[0023] The control unit 110 is a CPU (Central Processing Unit) that calls and executes programs stored in the storage unit 120 to realize various functions.

[0024] The control unit 110 includes, as its functions, an acquisition unit 1101, a planner 1102, and an output unit 1103. These functions are realized by the CPU executing an operation plan creation program 1201 stored in the storage unit 120.

[0025] The storage unit 120 is configured by a storage medium, for example, a hard disk drive (HDD), a flash memory, an electrically erasable programmable read-only memory (EEPROM), a random access read / write memory (RAM), a read-only memory (ROM), or any combination of these storage media. The storage unit 120 stores various programs, such as an operation plan creation program 1201, executed by the control unit 110 (CPU), and various data.

[0026] The communication unit 130 communicates with devices external to the operation plan creation device 10 .

[0027] The operation plan creation device 10 may be configured using a general-purpose computer device or may be configured as a dedicated hardware device. For example, the operation plan creation device 10 may be configured using a server computer connected to a communication network such as the Internet. Each function of the operation plan creation device 10 may be realized by cloud computing. The operation plan creation device 10 may be realized by a single computer, or the functions of the operation plan creation device 10 may be distributed and realized among multiple computers. The operation plan creation device 10 may be configured to have a website established using, for example, a WWW system.

[0028] The acquisition unit 1101 acquires information necessary to create an operation plan for the chemical plant 30 from the chemical plant 30. The planning unit 1102 creates an operation plan for the chemical plant 30 based on the information acquired by the acquisition unit 1101 from the chemical plant 30. The output unit 1103 outputs various information such as the operation plan for the chemical plant 30 created by the planning unit 1102.

[0029] Next, the flow of operations of the operation plan creation device 10 according to this embodiment will be described with reference to Fig. 3. Fig. 3 is a flowchart showing an example of the procedure of the operation plan creation method according to this embodiment.

[0030] The operation plan creation method according to this embodiment has the following preconditions. Preconditions: (1) The chemical plant 30 is in a normal operating state. Therefore, there is no mode change from the standby state, no shutdown, etc. (2) It is not permitted for the chemical plant 30 to enter a state where stable operation cannot be maintained or for production of the chemical product Mb to fall short of its target. Therefore, if the independent power POWa alone is insufficient, purchased power POWb is purchased. (3) The short-term hydrogen production plan includes the amount of product hydrogen Ma to be shipped and the hydrogen as a raw material for the chemical product Mb, and includes as a constraint that the remaining hydrogen in the H2 product tank 32 on the shipping date of the product hydrogen Ma is equal to or greater than the shipping amount.

[0031] 3 for each operation planning period. For each operation planning period, an operator specifies specific dates of the operation planning period to the operation planning device 10 using the terminal device 20.

[0032] (Step S1) The acquisition unit 1101 acquires the total hydrogen supply initial forecast amount A1 and the total hydrogen demand forecast amount A2 for the operation planning period from the chemical plant 30. The total hydrogen supply initial forecast amount A1 is the initial forecast amount of the total hydrogen supply amount for the operation planning period. The total hydrogen demand forecast amount A2 is the forecast amount of the total hydrogen demand for the operation planning period.

[0033] (Step S2) The acquiring unit 1101 acquires first time series data from the chemical plant 30. The first time series data is time series data of a total amount (first added amount) obtained by adding together the remaining amounts of hydrogen in the H2 product tank 32 and the H2 intermediate tank 35 at the start of the operation planning period and the cumulative initial predicted amount of hydrogen production by the water electrolysis apparatus 31 during the operation planning period.

[0034] (Step S3) The planning unit 1102 compares the total hydrogen supply initial forecast amount A1 and the total hydrogen demand forecast amount A2, which the acquisition unit 1101 acquired from the chemical plant 30. If the result of this comparison shows that the total hydrogen supply initial forecast amount A1 exceeds the total hydrogen demand forecast amount A2, the process proceeds to step S4. On the other hand, if the total hydrogen supply initial forecast amount A1 does not exceed the total hydrogen demand forecast amount A2, the process proceeds to step S5.

[0035] (Step S4) If the total initial predicted hydrogen supply amount A1 exceeds the total predicted hydrogen demand amount A2, it is predicted that the total hydrogen supply amount during the operation plan period will exceed the total hydrogen demand amount. Therefore, the independent power POWa alone is sufficient, and an operation plan is created without purchasing purchased power POWb. The planning unit 1102 calculates time series data of the cumulative planned hydrogen demand amount without purchasing power. The cumulative planned hydrogen demand amount is the cumulative planned amount of demand for hydrogen as a raw material for the chemical manufacturing equipment 34 during the operation plan period. A method for calculating the time series data of the cumulative planned hydrogen demand amount without purchasing power will be described later.

[0036] (Step S5) If the total initial predicted hydrogen supply amount A1 does not exceed the total predicted hydrogen demand amount A2, it is predicted that the total hydrogen supply amount during the operation plan period will be less than the total hydrogen demand amount, that is, the hydrogen supply amount during the operation plan period will be insufficient. Therefore, since the independent power POWa alone will be insufficient, an operation plan is created with purchased power POWb. The planner 1102 calculates time series data of the cumulative planned hydrogen demand amount with purchased power. The method for calculating the time series data of the cumulative planned hydrogen demand amount with purchased power will be described later.

[0037] (Step S6) Based on the time series data of the created cumulative planned amount of hydrogen demand, the planning unit 1102 creates operation plan data including various parameters of the load of the chemical plant 30 if there is no power purchase, and on the other hand, creates operation plan data including a plan of the amount of purchased power POWb and various parameters of the load of the chemical plant 30 if there is power purchase.

[0038] (Step S7) The output unit 1103 outputs the operation plan data created by the planner 1102. The operation plan data is transmitted to a predetermined destination such as the terminal device 20 or the chemical plant 30. When the planned shipping volume cannot be met, the output unit 1103 may transmit alert information notifying this fact together with the operation plan data. The worker changes the load of the chemical plant 30 based on the operation plan data received by the terminal device 20. Note that a load control device that automatically changes the load of the chemical plant 30 may be provided, and the output unit 1103 may transmit the operation plan data to the load control device, and the load control device may automatically change the load of the chemical plant 30 based on the operation plan data.

[0039] Next, a method for calculating time-series data of the cumulative planned amount of hydrogen demand with or without purchased power will be described.

[0040] [Method for calculating time series data of cumulative planned amount of hydrogen demand without purchasing power] A method for calculating time series data of cumulative planned amount of hydrogen demand without purchasing power will be described with reference to Figures 4 and 5. Figures 4 and 5 are diagrams for explaining a method for calculating time series data of cumulative planned amount of hydrogen demand without purchasing power according to this embodiment.

[0041] FIG. 4 shows first time-series data Wa1 and time-series data of the initial cumulative planned hydrogen demand amount (initial cumulative planned hydrogen demand amount time-series data) Wa2.

[0042] The first time-series data Wa1 is time-series data of a first added amount obtained by adding the cumulative total of the initial predicted amount of hydrogen production by the water electrolysis device 31 during the operation plan period to the sum A0 of the remaining amounts of hydrogen in the H2 product tank 32 and the H2 intermediate tank 35 at the start of the operation plan period. The initial predicted amount of hydrogen production by the water electrolysis device 31 during the operation plan period is the predicted amount of hydrogen produced by the water electrolysis device 31 using only the on-site power POWa. Because the on-site power POWa fluctuates depending on the weather, the amount of hydrogen produced by the water electrolysis device 31 using only the on-site power POWa also fluctuates depending on the weather. Therefore, the initial predicted amount of hydrogen production by the water electrolysis device 31 during the operation plan period is information predicted based on weather forecast information indicating a weather forecast that predicts weather conditions during the operation plan period. As illustrated in FIG. 4 , the first time-series data Wa1 is time-series data in which the amount of hydrogen production by the water electrolysis device 31 fluctuates in accordance with fluctuations in the on-site power POWa predicted based on the weather forecast information for the operation plan period.

[0043] The initial predicted total hydrogen supply amount A1 for the operation plan period is the value of the first time-series data Wa1 at the end of the operation plan period.

[0044] The initial hydrogen demand cumulative planned amount time-series data Wa2 is time-series data of the cumulative planned amount of hydrogen demand, which is made up of the shipment amount A3 of the product hydrogen Ma and the amount of hydrogen as a raw material for the chemical product Mb when the chemical production equipment 34 produces the chemical product Mb at a constant operation during the operation plan period. Therefore, as illustrated in Figure 4, the initial hydrogen demand cumulative planned amount time-series data Wa2 is represented by a straight line with a constant positive slope.

[0045] The total hydrogen demand forecast amount A2 is the value of the initial hydrogen demand cumulative plan amount time-series data Wa2 at the end of the operation plan period.

[0046] As shown in Figure 4, the initial forecasted total hydrogen supply amount A1 exceeds the forecasted total hydrogen demand amount A2. Therefore, the independent power POWa alone is sufficient, and an operation plan is created without purchasing purchased power POWb. The planner 1102 calculates time-series data of the cumulative planned hydrogen demand amount without purchasing power.

[0047] 5 is a diagram illustrating a method for calculating time-series data of the cumulative planned amount of hydrogen demand without purchasing electricity. In FIG. 5 , the operation plan period is divided into n calculation periods: a first calculation period (i=1), a second calculation period (i=2), a third calculation period (i=3), ..., and an nth calculation period (i=n). In this embodiment, the time-series data Wa3 of the cumulative planned amount of hydrogen demand is calculated so that the cumulative planned amount of hydrogen demand is less than the first time-series data Wa1 (first addition amount) in all calculation periods (i=1 to n) of the operation plan period and so that the sum of the differences "dfi" between the first time-series data Wa1 (first addition amount) and the cumulative planned amount of hydrogen demand for each calculation period (i=1 to n) of the operation plan period is maximized.

[0048] Specifically, the objective function of the following equation (1) is used to find the optimal solution for each parameter under the constraints of both the following equations (2) and (3).

[0049]

[0050]

[0051]

[0052] x1i is the cumulative total of the initial predicted amount of hydrogen produced by the water electrolysis device 31 using only its own power POWa at the end of the i-th calculation period. x2i is the remaining amount of hydrogen in the H2 intermediate tank 35 at the end of the i-th calculation period. x3i is the remaining amount of hydrogen in the H2 product tank 32 at the end of the i-th calculation period. y1i is the cumulative total of the demand for hydrogen as a raw material for the chemical product Mb used by the chemical production device 34 at the end of the i-th calculation period. y2i is the cumulative total of the shipped amount of product hydrogen Ma at the end of the i-th calculation period.

[0053] 5 illustrates time-series data Wa3 of the cumulative planned hydrogen demand amount, which is the result of using the objective function of equation (1) to find an optimal solution for each parameter under the constraints of both equations (2) and (3). This time-series data Wa3 of the cumulative planned hydrogen demand amount enables stable operation of the chemical production plant 34 so as to satisfy the total forecasted hydrogen demand amount A2 while leaving the maximum amount of spare capacity in the H2 intermediate tank 35. This has the effect of preventing a situation in which it is necessary to purchase purchased power POWb for stable operation of the chemical production plant 34. In the above-mentioned method for calculating time series data of the cumulative planned amount of hydrogen demand without purchasing electricity, the time series data Wa3 of the cumulative planned amount of hydrogen demand is calculated so as to maximize the sum of the difference "dif" between the first time series data Wa1 (first added amount) for each calculation period (i = 1 to n) of the operation planning period and the cumulative planned amount of hydrogen demand, but the calculation condition "maximizing the sum of the difference "dif" between the first time series data Wa1 (first added amount) for each calculation period (i = 1 to n) of the operation planning period and the cumulative planned amount of hydrogen demand" is not necessary.

[0054] [Method for calculating time series data of cumulative planned amount of hydrogen demand with power purchase] A method for calculating time series data of cumulative planned amount of hydrogen demand with power purchase will be described with reference to Figures 6 and 7. Figures 6 and 7 are diagrams for explaining a method for calculating time series data of cumulative planned amount of hydrogen demand with power purchase according to this embodiment.

[0055] FIG. 6 shows first time-series data Wb1 and time-series data of the initial cumulative planned hydrogen demand amount (initial cumulative planned hydrogen demand amount time-series data) Wa2.

[0056] 4 and 5 described above, the first time series data Wb1 is time series data of a first added amount obtained by adding the cumulative initial predicted amount of hydrogen production by the water electrolysis apparatus 31 during the operation planning period to the sum A0 of the remaining amounts of hydrogen in the H2 product tank 32 and the H2 intermediate tank 35 at the start of the operation planning period. The initial predicted total hydrogen supply amount A1 for the operation planning period is the value of the first time series data Wb1 at the end of the operation planning period. The initial cumulative planned hydrogen demand amount time series data Wa2 is the same as that in FIGS. 4 and 5 described above. The total predicted hydrogen demand amount A2 is the value of the initial cumulative planned hydrogen demand amount time series data Wa2 at the end of the operation planning period.

[0057] 6, the initial forecasted total hydrogen supply amount A1 is lower than the forecasted total hydrogen demand amount A2. Therefore, since the independent power POWa alone will not be sufficient, an operation plan is created with the purchase of purchased power POWb. The planner 1102 calculates time-series data of the cumulative planned hydrogen demand amount with the purchase of power.

[0058] 7 is a diagram illustrating a method for calculating time-series data of the cumulative planned hydrogen demand amount with power purchase. In Fig. 7 , as in Fig. 5 , the operation plan period is divided into n calculation periods: a first calculation period (i = 1), a second calculation period (i = 2), a third calculation period (i = 3), ..., and an nth calculation period (i = n). In this embodiment, when the total initial forecasted hydrogen supply amount A1 does not exceed the forecasted total hydrogen demand amount A2, the acquisition unit 1101 acquires time-series data (second time-series data) of the cumulative predicted amount of additional hydrogen production (cumulative predicted additional hydrogen production amount) to be produced by the water electrolysis device 31 using additional purchased power POWb. Next, the time series data Wb3 of the cumulative planned hydrogen demand amount is calculated so that the cumulative planned hydrogen demand amount is less than the time series data Wb1v of the second addition amount obtained by adding the first time series data Wb1 (first addition amount) and the second time series data (cumulative additional hydrogen production forecast amount) in all calculation periods (i = 1 to n) of the operation planning period, and so that the sum of the differences "dif" between the second addition amount (time series data Wb1v) and the cumulative planned hydrogen demand amount in each calculation period (i = 1 to n) of the operation planning period is maximized.

[0059] Specifically, the objective function of the above formula (1) is used to find the optimal solution for each parameter under the constraints of both the following formulas (4) and (5).

[0060]

[0061]

[0062] x1i is the cumulative total at the end of the i-th calculation period of the initial predicted amount of hydrogen production by the water electrolysis device 31 using only its own power POWa. x2i is the remaining amount of hydrogen in the H2 intermediate tank 35 at the end of the i-th calculation period. x3i is the remaining amount of hydrogen in the H2 product tank 32 at the end of the i-th calculation period. x4i is the cumulative total at the end of the i-th calculation period of the predicted amount of hydrogen production by the water electrolysis device 31 using only the additional purchased power POWb. y1i is the cumulative total at the end of the i-th calculation period of the hydrogen demand amount equivalent to the raw material for the chemical product Mb used by the chemical production device 34. y2i is the cumulative total at the end of the i-th calculation period of the shipped amount of product hydrogen Ma.

[0063] FIG. 7 illustrates time-series data Wb1v of the second addition amount, which is the sum of the first time-series data Wb1 (first addition amount) and the second time-series data (cumulative additional hydrogen production forecast amount). According to this time-series data Wb1v, the total hydrogen supply forecast amount A1v for the operation planning period exceeds the total hydrogen demand forecast amount A2. FIG. 7 also illustrates time-series data Wb3 of the cumulative planned hydrogen demand amount, which is the result of finding an optimal solution for each parameter using the objective function of equation (1) under the constraints of both equations (4) and (5). According to this time-series data Wb3 of the cumulative planned hydrogen demand amount, the chemical production plant 34 can be operated so as to satisfy the total hydrogen demand forecast amount A2 while minimizing the amount of purchased power POWb as much as possible. This has the effect of reducing the amount of purchased power while preventing the chemical production plant 34 from failing to produce chemical products Mb. In the above-mentioned method for calculating time series data of the cumulative planned amount of hydrogen demand with power purchase, the time series data Wb3 of the cumulative planned amount of hydrogen demand is calculated so as to maximize the sum of the difference "dif i" between the second addition amount (time series data Wb1v) for each calculation period (i = 1 to n) of the operation planning period and the cumulative planned amount of hydrogen demand, but the calculation condition "maximizing the sum of the difference "dif i" between the second addition amount (time series data Wb1v) for each calculation period (i = 1 to n) of the operation planning period and the cumulative planned amount of hydrogen demand" is not necessary.

[0064] If the planning unit 1102 determines that the planned shipment amount of the chemical product Mb cannot be obtained based on the time series data of the calculated cumulative planned amount of hydrogen demand, it transmits alert information to the terminal device 20 .

[0065] According to this embodiment, it is possible to create an operation plan for a chemical plant 30 that produces chemical products using hydrogen as a raw material produced by a water electrolysis device 31 (hydrogen production device) that uses electricity generated using renewable energy.

[0066] In the above-described embodiment, the present invention is applied to the chemical plant 30 that ships product hydrogen Ma, but it can also be applied to a chemical plant that does not ship product hydrogen. In the case of a chemical plant that does not ship product hydrogen, an H2 product tank is not required, and the constraints on the shipping amount of product hydrogen (Equation (3) or Equation (5)), the parameter x3i for the remaining amount in the H2 product tank, and the parameter y2i for the shipping amount of product hydrogen are not required.

[0067] Although an embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present invention.

[0068] Furthermore, a computer program for implementing the functions of each of the above-described devices may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be loaded into a computer system and executed. Note that the term "computer system" here may also include hardware such as an OS and peripheral devices. Furthermore, if a WWW system is used, the term "computer system" also includes the homepage provision environment (or display environment). Furthermore, "computer-readable recording medium" refers to a storage device such as a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disc), or a hard disk built into a computer system.

[0069] Furthermore, the term "computer-readable recording medium" also includes a storage medium that stores a program for a certain period of time, such as a volatile memory (e.g., a dynamic random access memory (DRAM)) within a computer system that serves as a server or client when the program is transmitted via a network such as the Internet or a communication line such as a telephone line. The program may also be transmitted from a computer system that stores the program in a storage device or the like to another computer system via a transmission medium or by transmission waves within the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has the function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may also be a program that realizes part of the aforementioned functions. Furthermore, the program may be a so-called differential file (differential program) that can realize the aforementioned functions in combination with a program already stored in the computer system.

[0070] 1...Operation plan creation system, 10...Operation plan creation device, 110...Control unit, 120...Memory unit, 130...Communication unit, 1101...Acquisition unit, 1102...Planning unit, 1103...Output unit, 1201...Operation plan creation program, 20...Terminal device, 30...Chemical plant, 31...Water electrolysis device (hydrogen production device), 32...H2 product tank, 33...Compressor, 34...Chemical production device, 35...H2 intermediate tank

Claims

1. An operation plan creation device for creating an operation plan for a chemical plant, comprising: a hydrogen production device that produces hydrogen using electric power generated by using renewable energy; a chemical production device that produces chemical products using the hydrogen produced by the hydrogen production device as a raw material; and an intermediate tank provided between the hydrogen production device and the chemical production device for storing the hydrogen produced by the hydrogen production device for buffering. An acquisition unit that acquires a total hydrogen supply initial prediction amount, which is an initial predicted amount of the total hydrogen supply amount during the operation plan period, a total hydrogen demand prediction amount, which is a predicted amount of the total hydrogen demand amount during the operation plan period, and first time-series data of a first addition amount obtained by adding the cumulative initial predicted amount of the hydrogen production amount of the hydrogen production device during the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period; a determination unit that determines whether the total hydrogen supply initial prediction amount exceeds the total hydrogen demand prediction amount; and a planning unit that, when the total hydrogen supply initial prediction amount exceeds the total hydrogen demand prediction amount, calculates time-series data of a cumulative planned amount of hydrogen demand, which is the cumulative planned amount of the hydrogen demand as a raw material of the chemical production device during the operation plan period in all calculation periods of the operation plan period, so that the cumulative planned amount of hydrogen demand is less than the first addition amount, and on the other hand, when the total hydrogen supply initial prediction amount does not exceed the total hydrogen demand prediction amount, the acquisition unit acquires second time-series data of the cumulative predicted amount of the additional hydrogen production amount produced by the hydrogen production device using additional electric power, and calculates the time-series data of the cumulative planned amount of hydrogen demand so that the cumulative planned amount of hydrogen demand is less than a second addition amount obtained by adding the first addition amount of the first time-series data and the cumulative amount of the second time-series data in all calculation periods of the operation plan period.

2. When the initial predicted total hydrogen supply amount exceeds the predicted total hydrogen demand amount, the planning unit calculates time-series data of the cumulative planned hydrogen demand amount so as to maximize the sum of the differences between the first addition amount and the cumulative planned hydrogen demand amount for each calculation period during the operation planning period. On the other hand, when the initial predicted total hydrogen supply amount does not exceed the predicted total hydrogen demand amount, the planning unit calculates time-series data of the cumulative planned hydrogen demand amount so as to maximize the sum of the differences between the second addition amount and the cumulative planned hydrogen demand amount for each calculation period during the operation planning period. The operation plan creation device according to claim 1.

3. The chemical plant further includes a product tank for storing hydrogen produced by the hydrogen production device for shipping. As the first addition amount, the total amount obtained by summing the remaining amounts of hydrogen in the intermediate tank and the product tank at the start of the operation planning period and the cumulative predicted initial production amount of hydrogen by the hydrogen production device during the operation planning period is used. As the cumulative planned hydrogen demand amount, the total amount obtained by summing the planned shipping amount of hydrogen during the operation planning period and the cumulative planned demand amount of hydrogen as a raw material for the chemical production device during the operation planning period is used. As a constraint condition when calculating the time-series data of the cumulative planned hydrogen demand amount, it is added that the remaining amount of hydrogen in the product tank on the hydrogen shipping date during the operation planning period is equal to or greater than the planned shipping amount. The operation plan creation device according to any one of claims 1 or 2.

4. When it is determined that the planned shipping amount of the chemical product cannot be obtained based on the time-series data of the cumulative planned hydrogen demand amount, the planning unit issues an alarm. The operation plan creation device according to claim 1.

5. A method for creating an operation plan for a chemical plant comprising a hydrogen production device that produces hydrogen using electric power generated by using renewable energy, a chemical production device that produces chemical products using hydrogen produced by the hydrogen production device, and an intermediate tank provided between the hydrogen production device and the chemical production device that stores hydrogen produced by the hydrogen production device for buffering, the method comprising: a first step of obtaining a total hydrogen supply initial predicted amount that is an initial predicted amount of the total hydrogen supply amount during the operation plan period and a total hydrogen demand predicted amount that is a predicted amount of the total hydrogen demand amount during the operation plan period; a second step of obtaining first time series data of a first addition amount obtained by adding a cumulative amount of an initial predicted amount of the hydrogen production amount of the hydrogen production device during the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period; a third step of determining whether the total hydrogen supply initial predicted amount exceeds the total hydrogen demand predicted amount; a fourth step of calculating time series data of the cumulative hydrogen demand planned amount, which is a planned amount of the cumulative demand for hydrogen as a raw material of the chemical production device during the operation plan period, so that the cumulative hydrogen demand planned amount is less than the first addition amount in all calculation periods during the operation plan period when the total hydrogen supply initial predicted amount exceeds the total hydrogen demand predicted amount; a fifth step of obtaining second time series data of a cumulative amount of a predicted amount of an additional hydrogen production amount produced by the hydrogen production device using additional electric power when the total hydrogen supply initial predicted amount does not exceed the total hydrogen demand predicted amount, and calculating time series data of the cumulative hydrogen demand planned amount so that the cumulative hydrogen demand planned amount is less than a second addition amount obtained by adding the first addition amount of the first time series data and the cumulative amount of the second time series data in all calculation periods during the operation plan period.

6. A computer of an operation plan creation device that creates an operation plan for a chemical plant including a hydrogen production device that produces hydrogen using electric power generated using renewable energy, a chemical production device that produces chemical products using the hydrogen produced by the hydrogen production device, and an intermediate tank provided between the hydrogen production device and the chemical production device that stores the hydrogen produced by the hydrogen production device for buffering. A first step of obtaining a total hydrogen supply initial prediction amount that is an initial predicted amount of the total hydrogen supply amount during the operation plan period and a total hydrogen demand prediction amount that is a predicted amount of the total hydrogen demand amount during the operation plan period. A second step of obtaining first time-series data of a first addition amount obtained by adding the cumulative initial predicted amount of the hydrogen production amount of the hydrogen production device during the operation plan period to the remaining amount of hydrogen in the intermediate tank at the start of the operation plan period. A third step of determining whether the total hydrogen supply initial prediction amount exceeds the total hydrogen demand prediction amount. A fourth step of calculating time-series data of the cumulative hydrogen demand planned amount, which is the planned amount of the cumulative demand for hydrogen as a raw material of the chemical production device during the operation plan period, so that the cumulative hydrogen demand planned amount is less than the first addition amount in all calculation periods during the operation plan period when the total hydrogen supply initial prediction amount exceeds the total hydrogen demand prediction amount. A fifth step of obtaining second time-series data of the cumulative predicted amount of the additional hydrogen production amount produced by the hydrogen production device using additional electric power when the total hydrogen supply initial prediction amount does not exceed the total hydrogen demand prediction amount, and calculating time-series data of the cumulative hydrogen demand planned amount so that the cumulative hydrogen demand planned amount is less than a second addition amount obtained by adding the first addition amount of the first time-series data and the cumulative second time-series data in all calculation periods during the operation plan period. A computer program for causing a computer to execute the above steps.

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