Energy management device and energy management method

Abstract

To provide an energy management device that ensures the maintenance of system inertial force. [Solution] The energy management device 10 includes a target system inertia calculation unit 121 that calculates a target surplus electricity amount, which is the portion of the renewable energy power generation amount used for hydrogen production, based on a predicted electricity demand value for the power grid including renewable energy power sources and synchronous power sources, and a predicted renewable energy power generation amount, which is the predicted power generation amount of the renewable energy power sources, and also calculates a target system inertia force for the power grid. The fuel used for power generation of the synchronous power source includes hydrogen produced with the electricity generated by the renewable energy power source. The device further includes a power generation planning unit 122 that calculates a target synchronous power generation amount, which is the target amount of power generation for the synchronous power source in each time period, based on the predicted electricity demand value, the predicted renewable energy power generation amount, the target surplus electricity amount, and the target system inertia force.

Description

[Technical Field]

[0001] This disclosure relates to an energy management device and an energy management method. [Background technology]

[0002] As a technology for managing the operation of renewable energy power sources and synchronous power sources, for example, the technologies described in Patent Documents 1 and 2 are known. Specifically, Patent Document 1 describes "determining which renewable energy power generation equipment will reduce its output when an accident corresponding to the assumed target accident case occurs, based on the total reduction amount determined by the renewable energy reduction amount addition unit."

[0003] Furthermore, Patent Document 2 describes "determining the co-firing ratio of the hydrogen or ammonia burned by the combustion device and the fossil fuel, and controlling the combustion by the combustion device." [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-96472 [Patent Document 2] Japanese Patent Publication No. 2024-113371 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, the technologies described in Patent Documents 1 and 2 do not particularly consider the securing of grid inertial force in power systems, and there is room for improvement.

[0006] Therefore, the objective of this disclosure is to provide an energy management device, etc., that ensures the maintenance of system inertial force. [Means for solving the problem]

[0007] In order to solve the above problems, the energy management device according to the present disclosure calculates a target surplus power amount, which is a target value of the amount of power generation of the renewable energy power source used for hydrogen production, based on a predicted power demand value of a power system including a renewable energy power source and a synchronous power source, and a predicted renewable energy power generation amount, which is a predicted value of the power generation amount of the renewable energy power source, and further includes a target system inertia force calculation unit that calculates a target system inertia force of the power system. The fuel used for power generation of the synchronous power source includes hydrogen produced from the power generated by the renewable energy power source, and further includes a power generation plan unit that calculates a target synchronous power source power generation amount, which is a target value of the power generation amount of the synchronous power source in each time period, based on the predicted power demand value, the predicted renewable energy power generation amount, the target surplus power amount, and the target system inertia force.

Advantages of the Invention

[0008] According to the present disclosure, it is possible to provide an energy management device or the like that secures system inertia force.

Brief Description of the Drawings

[0009] [Figure 1] It is a configuration diagram including an energy management device according to an embodiment. [Figure 2] It is a diagram showing the hardware configuration of an energy management device according to an embodiment [Figure 3] It is a functional block diagram of an energy management device according to an embodiment. [Figure 4] It is a diagram showing the relationship between the renewable energy ratio and the power fluctuation rate in an energy management device according to an embodiment. [Figure 5] It is a diagram showing the relationship between the hydrogen co-firing ratio and the thermal efficiency of a synchronous power source in an energy management device according to an embodiment. [Figure 6] It is a diagram showing the relationship between the load factor and the hydrogen co-firing ratio of a synchronous power source in an energy management device according to an embodiment. [Figure 7] It is a flowchart of the process executed by the processing unit of the energy management device according to an embodiment. [Figure 8]This flowchart shows the details of the process in step S105 of Figure 7 in the energy management device according to the embodiment. [Figure 9] This is an example of the calculation results related to the operation plan of synchronous power supplies and renewable energy power supplies by the energy management device according to the embodiment. [Figure 10] This is a diagram showing the configuration of an energy management device, including a modified example. [Figure 11] This is a functional block diagram of an energy management device with modified specifications. [Modes for carrying out the invention]

[0010] <<Embodiment>> Figure 1 is a configuration diagram including an energy management device 10 according to an embodiment. In Figure 1, power lines are shown as solid lines, and signal lines as dashed lines. Furthermore, in Figure 1, hydrogen supply lines, such as piping through which hydrogen flows, are shown as double lines. The energy management device 10 shown in Figure 1 is a device that manages the electrical energy and grid inertial force of the energy system 100. Below, we will first briefly describe the energy system 100, which is the target of the energy management device 10, and then describe the energy management device 10 in detail.

[0011] As shown in Figure 1, the energy system 100 is composed of a synchronous power supply 21, ..., 2n, a renewable energy power supply 31, ..., 3i, an inverter 41, ..., 4i, multiple circuit breakers 50, a hydrogen production device 61, ..., 6i, a hydrogen storage device 71, ..., 7i, and consumers 81, ..., 8k. Note that the "n", "i", and "k" included in the signs of each component are natural numbers.

[0012] The synchronous power supplies 21, ..., 2n are generators that possess synchronous force and system inertia force, and are connected to the transmission and distribution line L via the circuit breaker 50. Here, "synchronous force" refers to the property of trying to rotate at the same rotational speed as other synchronous power supplies connected to the power system G. "System inertia force" refers to the ability to maintain frequency in response to fluctuations in the balance of power supply and demand. In this embodiment, frequency fluctuations in the power system G are suppressed by the synchronous power supplies 21, ..., 2n.

[0013] As such synchronous power supplies 21, ..., 2n, for example, a generator configured to convert the kinetic energy of a turbine (not shown) into electrical energy can be used. Alternatively, instead of a turbine, the synchronous power supplies 21, ..., 2n may be driven by an engine (not shown). As shown in Figure 1, the output side of each of the synchronous power supplies 21, ..., 2n is connected to the power transmission and distribution line L via a power line.

[0014] In previous technologies, synchronous power sources often used hydrocarbon fuels (fossil fuels) for power generation. However, in this embodiment, hydrogen is produced and stored using the electricity generated by renewable energy power sources 31, ..., 3i, and this hydrogen is used as fuel for the synchronous power sources 21, ..., 2n. In other words, the fuel used for power generation by the synchronous power sources 21, ..., 2n includes hydrogen produced using the electricity generated by renewable energy power sources 31, ..., 3i. This reduces the CO2 emissions of the energy system 100. Furthermore, the synchronous power sources 21, ..., 2n are capable of mixed combustion (co-firing) of hydrogen and hydrocarbon fuels. Examples of hydrocarbon fuels used include natural gas, diesel fuel, and gasoline.

[0015] Renewable energy sources 31, ..., 3i are power generation facilities (asynchronous power sources) that convert predetermined renewable energy into electricity. Examples of such renewable energy sources 31, ..., 3i include solar power generation facilities, wind power generation facilities, as well as geothermal power generation facilities, hydroelectric power generation facilities, and tidal power generation facilities. As shown in Figure 1, renewable energy source 31 is connected to the power transmission and distribution line L via an inverter 41 and a circuit breaker 50 in sequence (the same applies to other renewable energy sources 3i, etc.).

[0016] The inverter 41 is a power converter that converts the DC power generated by the renewable energy power source 31 into AC power (other inverters 4i etc. function similarly). The circuit breaker 50 switches between electrical connection and interruption. In addition, various measuring instruments (not shown) for the protection, control, and monitoring of the power system G are appropriately connected to the transmission and distribution lines L.

[0017] As shown in Figure 1, the synchronous power supplies 21, ..., 2n, the renewable energy power supplies 31, ..., 3i, and the inverters 41, ..., 4i constitute a single power system G. This power system G is connected to an external power system H via a connection point C. The external power system H is a power system outside the scope of energy system 100.

[0018] The hydrogen production device 61 is a device that produces hydrogen using a portion (surplus power) of the electricity generated by the renewable energy power source 31. For example, a water electrolysis device that generates hydrogen (and oxygen) by the electrolysis of water is used as such a hydrogen production device 61. The hydrogen produced in the hydrogen production device 61 is led to the hydrogen storage device 71. The hydrogen storage device 71 is a tank for storing hydrogen. The hydrogen stored in the hydrogen storage device 71 is supplied to the synchronous power sources 21, ..., 2n as needed via the hydrogen supply line P. The same applies to the other hydrogen production devices 6i and hydrogen storage devices 7i.

[0019] The example in Figure 1 shows a configuration in which hydrogen storage devices 71, ..., 7i and synchronous power supplies 21, ..., 2n are connected via a hydrogen supply line P, but the configuration is not limited to this. For example, hydrogen storage device 71 and synchronous power supply 21 may be connected via a predetermined hydrogen supply line, while hydrogen storage device 7i and synchronous power supply 2n may be connected via a different hydrogen supply line. Alternatively, hydrogen may be transported from hydrogen storage devices 71, ..., 7i to synchronous power supplies 21, ..., 2n as appropriate using means of transport such as automobiles, railway vehicles, or ships.

[0020] Customers 81, ..., 8k are load equipment connected to the transmission and distribution lines L of the power system G. Examples of such load equipment include air conditioning and lighting equipment, as well as production equipment and communication equipment. Power generated by synchronous power sources 21, ..., 2n and renewable energy power sources 31, ..., 3i is supplied to customers 81, ..., 8k via the transmission and distribution lines L.

[0021] While renewable energy sources 31, ..., 3i can contribute to reducing CO2 emissions, their power generation is prone to fluctuations due to weather changes. Therefore, synchronous power sources 21, ..., 2n are included as components of the power system G to suppress frequency fluctuations in the power system G even when the balance of power supply and demand changes. As described above, since synchronous power sources 21, ..., 2n have system inertia, they can suppress frequency fluctuations and stabilize the power system G. In this embodiment, the energy management device 10, which will be described next, calculates the target system inertia and creates a predetermined power generation plan based on this target system inertia, etc.

[0022] Figure 2 shows the hardware configuration of the energy management device 10. The energy management device 10 has a hardware configuration comprising a CPU 10a (Central Processing Unit), RAM 10b (Random Access Memory), ROM 10c (Read Only Memory), memory 10d, a communication interface 10e, and an input / output interface 10f, all of which are predeterminedly connected via an internal bus 10g. Such an energy management device 10 may be a single computer, or it may be a configuration in which multiple computers are predeterminedly connected via communication lines or a network.

[0023] The CPU 10a is a processor that executes predetermined processes. The CPU 10a reads a predetermined software program from the ROM 10c or memory 10d and loads it into the RAM 10b, thereby executing the program. Alternatively, an MPU (Micro Processing Unit) or the like may be used as the processor instead of the CPU 10a. Memory 10d is a non-volatile memory that stores predetermined programs and data. Examples of such memory 10d include HDDs (Hard Disk Drives), SSDs (Solid State Drives), flexible disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, and magnetic tapes.

[0024] The communication interface 10e is an interface used for communication via a network (not shown). The aforementioned network (not shown) may be a WAN (Wide Area Network) such as the Internet, a LAN (Local Area Network) such as Wi-Fi® or Ethernet, or a mixture of both. As will be described in detail later, the energy management device 10 communicates with synchronous power supplies 21, ..., 2n (see Figure 1), renewable energy power supplies 31, ..., 3i (see Figure 1), and consumers 81, ..., 8k (see Figure 1) sequentially via the communication interface 10e and the network (not shown). In such communication, communication devices (not shown) such as NICs (Network Interface Cards) may be used as appropriate.

[0025] The input / output interface 10f is an interface for inputting data from the input device D1 and outputting data to the display device D2. The input device D1 is, for example, a keyboard, mouse, or touch panel, and is used when the user inputs data. The display device 30 displays the calculation results of the energy management device 10 in a predetermined format. For example, a liquid crystal display is used as such a display device 30. Data input and output may also be performed using a mobile terminal (not shown) such as a smartphone or tablet.

[0026] Next, the functional configuration of the energy management device 10 will be explained using Figure 3. It should be assumed that the power demand of consumers 81, ..., 8k (see Figure 1) changes moment by moment, and that the power generated by renewable energy sources 31, ..., 3i (see Figure 1) also changes moment by moment. Furthermore, it should be assumed that the energy management device 10 creates power generation plans for each hour from the current time up to 24 hours in advance.

[0027] Figure 3 is a functional block diagram of the energy management device 10. As shown in Figure 3, the energy management device 10 is composed of a storage unit 11 and a processing unit 12. The storage unit 11 has predetermined programs and data stored in it in advance, and the calculation results of the processing unit 12 are stored there as appropriate. The processing unit 12 includes a target system inertia force calculation unit 121, a power generation planning unit 122, a hydrogen storage amount calculation unit 123, a hydrogen co-firing ratio planning unit 124, and a previous value holding unit 125.

[0028] The target system inertia force calculation unit 121 calculates the target surplus power amount and the target system inertia force of the power system G (see Figure 1) based on the predicted power demand and the predicted renewable energy generation amount of the power system G. Here, "target system inertia force" is the target value of the system inertia force in the power system G. As described above, the system inertia force is ensured by the synchronous power sources 21, ..., 2n (see Figure 1).

[0029] The "electricity demand forecast" shown in Figure 3 is the forecast value of electricity demand for consumers 81, ..., 8k (see Figure 1) (for example, a forecast value for 24 hours, calculated hourly). The "renewable energy generation forecast" is the forecast value of the total generation amount for renewable energy sources 31, ..., 3i (see Figure 1) (for example, a forecast value for 24 hours, calculated hourly). The electricity demand forecast and renewable energy generation forecast may be calculated by the energy management device 10 using a well-known method, or they may be obtained from an external computer (not shown) via a network (not shown).

[0030] The target system inertia force calculation unit 121 first calculates the renewable energy ratio as preparation for calculating the target system inertia force. Here, the "renewable energy ratio" is the ratio of the predicted amount of renewable energy generation to the predicted amount of electricity demand. This predicted value of the renewable energy ratio RE(t)[-] is expressed by the following equation (1).

[0031]

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[0032] In equation (1), t represents a time period (e.g., each hourly time period) that constitutes a predetermined calculation period (e.g., 24 hours from the current time). Also, i in equation (1) is a component of set I of renewable energy sources 31, ..., 3i (see Figure 1). In equation (1), k represents a component of set K of consumers 81, ..., 8k (see Figure 1). Furthermore, Pre(t)[MW] is the predicted renewable energy generation amount for a predetermined time period t. D(t)[MW] is the predicted electricity demand for a predetermined time period t.

[0033] Figure 4 shows the relationship between the renewable energy ratio and the rate of electricity fluctuation. In Figure 4, the horizontal axis of the graph represents the renewable energy ratio, and the vertical axis represents the power fluctuation rate. Here, the "power fluctuation rate" is a ratio that shows the maximum extent to which the power transmitted through the power grid G ​​(see Figure 1) fluctuates. As shown in Figure 4, there is a monotonically increasing relationship where the higher the renewable energy ratio, the higher the power fluctuation rate. In other words, the more renewable energy power sources 31,...,3i (see Figure 1) there are (the amount of power generated), the more likely the power in the power grid G ​​(see Figure 1) is to fluctuate. This is because the power generated by renewable energy power sources 31,...,3i (see Figure 1) is likely to fluctuate in response to changes in weather, etc.

[0034] The relationship between the renewable energy ratio and the power fluctuation rate, as shown in Figure 4, is pre-stored in the storage unit 11 (see Figure 3) as a predetermined formula or data table. The target system inertia force calculation unit 121 (see Figure 3) calculates the power fluctuation rate of the power system based on the renewable energy ratio (and the relationship in Figure 4), and further calculates the target system inertia force J [MW·s] based on the power fluctuation rate and the power demand forecast value, as shown in equation (2) below.

[0035]

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[0036] In equation (2), C1(t)[-] is the power fluctuation rate during a predetermined time period t. D(t)[MW] is the predicted power demand value during the predetermined time period t, as described above. F0 is a predetermined reference frequency [Hz] (50[Hz] or 60[Hz]) and is set in advance. RoCoF is a predetermined allowable frequency change rate [Hz / s] and is set in advance as a fixed value. The target system inertia force J calculated in this way is used to calculate the target value of the power generation amount (target synchronous power generation amount) of the synchronous power sources 21, ..., 2n (see Figure 1).

[0037] Furthermore, in order to ensure the grid inertia of the power grid G ​​(see Figure 1), an upper limit value Lre (constant) is set in advance for the renewable energy ratio, as shown in Figure 4. If the predicted renewable energy ratio RE(t) exceeds the upper limit value Lre, the excess amount of electricity generated is used as surplus power for hydrogen production.

[0038] The target system inertia force calculation unit 121 (see Figure 3) calculates the target surplus electricity amount TPsu [MW], which is the target value of the amount of electricity generated by the renewable energy power sources 31, ..., 3i (see Figure 1) that will be used for hydrogen production, based on the following equation (3). Incidentally, the "T" at the beginning of the symbol for target surplus electricity amount (TPsu(t)) indicates that it is the total sum of the surplus electricity amounts of the renewable energy power sources 31, ..., 3i.

[0039]

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[0040] In equation (3), RE(t)[-] is a predicted value of the renewable energy ratio and is calculated based on equation (1) described above. Lre[-] is an upper limit value for the renewable energy ratio (see Figure 4). D(t)[MW] is a predicted value of electricity demand during a predetermined time period, as described above. As shown in equation (3), the target system inertia force calculation unit 121 (see Figure 3) allocates the surplus when the renewable energy ratio RE(t) exceeds a predetermined upper limit value Lre as a target surplus electricity amount TPsu for hydrogen production.

[0041] Furthermore, when producing hydrogen using the power generated by renewable energy sources 31, ..., 3i (see Figure 1), the target system inertia force calculation unit 121 (see Figure 3) should prioritize the use of hydrogen production equipment connected to hydrogen storage devices with relatively small hydrogen storage capacities over other hydrogen production equipment. For example, suppose that among the multiple hydrogen storage devices 71, ..., 7i shown in Figure 1, hydrogen storage device 71 has a relatively small hydrogen storage capacity. In such a case, the target system inertia force calculation unit 121 sets the output destination of the power generated by the renewable energy source 31 to prioritize the use of hydrogen production equipment 61 connected to hydrogen storage device 71. This avoids the loss of opportunity, such as being unable to perform hydrogen co-firing with a synchronous power source due to a small hydrogen storage capacity.

[0042] The power generation planning unit 122 shown in Figure 3 creates an operation plan for the synchronous power sources 21, ..., 2n (see Figure 1). Specifically, the power generation planning unit 122 calculates the target synchronous power generation amount based on the predicted power demand, the predicted renewable energy generation amount, the target surplus power amount, and the target grid inertia force. Here, "target synchronous power generation amount" refers to the target value of the power generation amount for each time period of the synchronous power sources 21, ..., 2n.

[0043] The power generation planning unit 122 first calculates the target total synchronous power generation TPsy(t)[MW] as the sum of the target power generation values ​​of the synchronous power sources 21, ..., 2n in each time period, based on the following equation (4). Incidentally, the "T" at the beginning of the symbol for the target total synchronous power generation (TPsy(t)) indicates that it is the sum (total) of the power generation amounts of the synchronous power sources 21, ..., 2n (see Figure 1).

[0044]

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[0045] In equation (4), D(t)[MW] is the predicted power demand value for a given time period t, as described above. Pre(t)[MW] is the predicted renewable energy generation value for a given time period t, as explained in equation (1). TPsu(t)[MW] is the target surplus power calculated based on equation (3). In short, equation (4) represents the calculation of the target synchronous power generation amount TPsy(t) by subtracting the sum of the power generation amounts supplied from renewable energy sources 31,...,3i (see Figure 1) to the power grid G ​​(see Figure 1) from the predicted power demand value D(t).

[0046] Next, the power generation planning unit 122 performs calculations using equation (5) as the objective function to determine how to drive the synchronous power supplies 21, ..., 2n (see Figure 1) in each time period.

[0047]

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[0048] Note that A is included in equation (5) n This is a predetermined coefficient [-] applied to the fuel cost of hydrocarbon fuels when driving the synchronous power supply 2n (n=1,...,n: see Figure 1), and is set in advance. n(t) is the individual target synchronous power generation amount [MW] when driving the synchronous power supply 2n (see Figure 1) during a predetermined time period t. B is the startup cost [-] of the synchronous power supply 2n, which is set in advance. Xsy n (t) is a 0-1 variable relating to the startup of the synchronous power supply 2n. For example, if the synchronous power supply 2n is started during a predetermined time period t, then during that time period t, Xsy n The value of (t) is set to 1. On the other hand, if the synchronous power supply 2n is not started during a predetermined time period t, then Xsy n The value of (t) is set to 0.

[0049] Equation (5), as the objective function, represents minimizing the total cost required for driving the synchronous power supplies 21, ..., 2n. The target synchronous power supply generation amount Psy mentioned above is also expressed as follows. n (t) and the 0-1 variable Xsy n (t) is set as an explanatory variable in equation (5).

[0050] When calculating the objective function in equation (5), the power generation planning unit 122 performs mathematical optimization so that the following constraints in equations (6) and (7) are satisfied. Equation (6) is the first constraint, which is that the sum of the inertia constants of the synchronous power sources 21, ..., 2n (see Figure 1) is equal to or greater than the target system inertia force J(t).

[0051]

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[0052] Note that M is included in equation (6). n (t) is the inertia constant [MW·s] representing the inertia force of the synchronous power supply 2n (n=1,…,n: see Figure 1), and is preset. J(t) is the target system inertia force at a predetermined time period t, and is calculated based on equation (2) described above.

[0053] In addition, the following formula (7) represents a second constraint condition that the power supply-demand balance is satisfied. The power generation planning unit 122 (see FIG. 3) ensures that the power generation amounts of the synchronous power sources 2n (n = 1, …, n: see FIG. 1) in each time period satisfy the constraint conditions of the following formula (7).

Number

[0054] Note that Psy n (t) on the left side of formula (7) is the power generation amount of the synchronous power sources 2n (n = 1, …, n: see FIG. 1) in a predetermined time period t. Also, the right side of formula (7) is the target total synchronous power generation amount TPsy(t), which is calculated based on the above-mentioned formula (4). Formula (7) represents that the sum of the power generation amounts of the synchronous power sources 21, …, 2n is equal to the target synchronous power generation amount TPsy(t).

[0055] As described in formula (5) above, the power generation planning unit 122 determines the target synchronous power generation amount Psy n (t) and the 0-1 variable Xsy n (t) (indicating the presence or absence of starting the synchronous power source) of the synchronous power sources 21, …, 2n when the sum of the fuel costs and startup costs of the synchronous power sources 21, …, 2n is minimized while satisfying the constraint conditions of formula (6) and formula (7) in a predetermined calculation target period (for example, 24 hours from the current time). That is, the power generation planning unit 122 sets the startup timings of the synchronous power sources 21, …, 2n and the power generation amounts in each time period.

[0056] In this way, the power generation planning unit 122 aims to minimize the cost required for the operation of the synchronous power sources (formula (5)) under the first constraint condition (formula (6)) that the sum of the inertia constants M n (t) of the plurality of synchronous power sources 21, …, 2n is equal to or greater than the target system inertia force J(t), and the second constraint condition (formula (7)) that the power supply-demand balance is maintained in the power system G, and calculates the target synchronous power generation amount Psy n (t) of the plurality of synchronous power sources 21, …, 2n in each time period.

[0057] The hydrogen storage amount calculation unit 123 shown in Figure 3 calculates the amount of hydrogen stored in each time period based on the hydrogen consumption of the synchronous power sources 21, ..., 2n (see Figure 1) and the target surplus power amount. The aforementioned "hydrogen consumption" refers to the total amount of hydrogen consumed when hydrogen produced by the electricity generated by the renewable energy power sources 31, ..., 3i (see Figure 1) is co-fired with hydrocarbon fuels to become fuel for the synchronous power sources 21, ..., 2n. The previous value retention unit 125 shown in Figure 3 retains (stores) the previous value of the total hydrogen consumption (previous calculation result) and the previous value of the total hydrogen storage amount in the hydrogen consumption calculation that is repeated at predetermined intervals.

[0058] The hydrogen storage amount calculation unit 123 calculates the total amount of hydrogen stored in a predetermined time period t, VHy[Nm], based on the following equation (8). 3 Perform the calculation for ].

[0059]

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[0060] In equation (8), VHy(t-1) is the previous value of the total amount of hydrogen stored, and is held by the previous value retention unit 125. TPsu(t)[MW] is the target surplus power amount in a predetermined time period t, and is calculated based on equation (3) described above. η is the efficiency [Nm³] of each of the hydrogen production devices 61, ..., 6i (see Figure 1). 3 [ / MW] is pre-set. CHy(t-1) is the previous value of the total hydrogen consumption.

[0061] The hydrogen co-firing ratio planning unit 124 (see Figure 3) calculates the hydrogen co-firing ratio at the synchronous power sources 21, ..., 2n (see Figure 1) based on the target synchronous power generation amount and hydrogen storage amount. Here, the "hydrogen co-firing ratio" is the proportion of hydrogen when hydrogen and hydrocarbon fuels are mixed and burned at the synchronous power sources 21, ..., 2n. First, the hydrogen co-firing ratio planning unit 124 calculates the target synchronous power load factor Lsy for the synchronous power source 2n (n=1, ..., n). n(t)[-] is calculated based on the following equation (9). Here, "target synchronous power supply load factor" is the target value of the load factor of the synchronous power supplies 21,...,2n. Also, "load factor" is the ratio of the amount of power generated by the synchronous power supplies 21,...,2n to the rated power generation amount.

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[0062] Note that MaxPsy included in equation (9) n (t) is the rated output [MW] of the synchronous power supply 2n (n=1,...,n), and is preset for each of the synchronous power supplies 21,...,2n (see Figure 1). n (t) is the individual target synchronous power generation amount [MW] for each of the synchronous power sources 21, ..., 2n that minimizes the objective function of equation (5) described above. The hydrogen co-firing ratio planning unit 124 (see Figure 3) calculates the hydrogen co-firing ratio based on the relationship between the load factor of the synchronous power source and the increase ratio of the thermal efficiency of the synchronous power source, as will be explained below.

[0063] Figure 5 shows the relationship between the hydrogen co-firing ratio and thermal efficiency of a synchronous power supply. In Figure 5, the horizontal axis represents the hydrogen co-firing ratio in the synchronous power supply, and the vertical axis represents the thermal efficiency when performing hydrogen co-firing in the synchronous power supply. Figure 5 shows graph F1, which illustrates the characteristics when the engine generator, which is the synchronous power supply, is driven at the maximum load factor, and graph F2, which illustrates the characteristics when it is driven under the minimum load factor conditions.

[0064] As shown in Figure 5, the graph F1 representing the maximum load factor is steeper than the graph F2 representing the minimum load factor. In other words, the rate at which the heat exchange efficiency increases with increasing hydrogen co-firing ratio (referred to as the rate of increase in thermal efficiency) is higher in graph F1 than in graph F2. Thus, the inventors have found that the higher the load factor of the synchronous power supply, the greater the effect of combustion improvement by hydrogen co-firing. Therefore, in this embodiment, as shown in Figure 6, the hydrogen co-firing ratio in the synchronous power supply is increased as the load factor of the synchronous power supply increases.

[0065] Figure 6 shows the relationship between the load factor and the hydrogen co-firing ratio of the synchronous power supply. In Figure 6, the horizontal axis represents the load factor of the synchronous power supply, and the vertical axis represents the hydrogen co-firing ratio. As shown in Figure 6, the higher the load factor of the synchronous power supply, the higher the hydrogen co-firing ratio is set. This relationship between the synchronous power supply load factor and the hydrogen co-firing ratio is set as a predetermined formula or data table and is stored in the storage unit 11 (see Figure 3) in advance.

[0066] The hydrogen co-firing ratio planning unit 124 (see Figure 3) sets the target synchronous power load ratio Lsy based on the above-mentioned formula (9). n Based on (t) and the data shown in Figure 6 (relationship between the load factor of the synchronous power supply and the hydrogen co-firing ratio), the hydrogen co-firing ratio of the synchronous power supply at each time period t is RHy n The (t)[-] calculation is performed. Specifically, the hydrogen co-firing ratio planning unit 124 increases the hydrogen co-firing ratio of the synchronous power supply as the load factor of the synchronous power supply increases.

[0067] Furthermore, the hydrogen co-firing ratio planning unit 124 (see Figure 3) calculates the total CO2 emissions E of the synchronous power sources 21, ..., 2n (see Figure 1) during a predetermined time period t. CO2 (t) is calculated based on the following equation (10).

[0068]

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[0069] Note that RHy is included in equation (10). n (t) is the hydrogen co-firing ratio during a predetermined time period t, and is calculated based on the data in Figure 6, as described above. Incidentally, the numerator on the right side of equation (20) contains (1-RHy n (t)) is the co-combustion ratio of hydrocarbon fuels. Also, Psy n (t) is the target synchronous power generation [MW] when the value of the objective function in equation (5) above is minimized (i.e., the cost is minimized). dt is a predetermined calculation step [h] (e.g., 1 hour). Also, GHG CHThe CO2 emission factor of hydrocarbon fuels [tCO2 / Nm 3 ] is set in advance. η is the efficiency [Nm³] of the hydrogen production apparatus 61, ..., 6i (see Figure 1), as explained in equation (8). 3 It is set to / MW] and is pre-configured. Also, ρ CH The volumetric energy density of hydrocarbon fuels [MWh / Nm³] 3 This is pre-set.

[0070] The hydrogen co-firing ratio planning unit 124 (see Figure 3) calculates the hydrogen co-firing ratio so that the sum of CO2 emissions from multiple synchronous power sources 21, ..., 2n (see Figure 1) is less than or equal to a predetermined target CO2 emission. For example, the sum of CO2 emissions E based on equation (10) CO2 If (t) exceeds a predetermined target CO2 emission, the hydrogen co-firing ratio planning unit 124 rearranges each time period included in a predetermined calculation period (for example, 24 hours from the current time) in descending order of hydrogen co-firing ratio. The hydrogen co-firing ratio planning unit 124 then increases the hydrogen co-firing ratio in the time period at the top of the aforementioned order by a predetermined value (for example, 5%). This process is repeated for a predetermined number of times until the sum of CO2 emissions falls below the target CO2 emission.

[0071] Furthermore, when increasing the hydrogen co-firing ratio during the time period with the highest ratio, if the hydrogen co-firing ratio for that time period reaches the upper limit of 1 (hydrogen-only firing), the hydrogen co-firing ratio planning unit 124 performs the same process for the next highest-ranking time period. This increases the hydrogen co-firing ratio under conditions of high thermal efficiency, allowing for efficient use of hydrogen. As a result, CO2 emissions from the energy system 100 (see Figure 1) can be effectively reduced.

[0072] After calculating the hydrogen co-firing ratio of the synchronous power supplies 21, ..., 2n (see Figure 1) in this manner, the hydrogen co-firing ratio planning unit 124 (see Figure 3) calculates the hydrogen consumption CHy(t) of the synchronous power supplies 21, ..., 2n based on the following equation (11). The hydrogen consumption CHy(t) represents the total amount of hydrogen consumed by the synchronous power supplies 21, ..., 2n during a predetermined time period t.

[0073]

number

[0074] Note that RHy is included in equation (11). n (t) is the hydrogen co-firing ratio during a predetermined time period t, as explained in equation (10). Also, Psy n (t) is the target synchronous power generation amount [MW], as explained in equation (5). dt is a predetermined calculation step [h] (e.g., 1 hour). η n (t) is the thermal efficiency [-] of the synchronous power supply 2n (n=1,…,n), which is set in advance. Note that the thermal efficiency η is obtained from a two-dimensional table of the hydrogen co-firing ratio and the load factor of the synchronous power supply. n (t) may be set. ρ included in equation (11) Hy This is the volumetric energy density of hydrogen [MWh / Nm³]. 3 This is pre-set.

[0075] For example, when setting the hydrogen co-firing ratio for synchronous power supplies 21, ..., 2n (see Figure 1), there may be periods when hydrogen consumption exceeds hydrogen storage capacity. In this case, the hydrogen co-firing ratio planning unit 124 (see Figure 3) sets the hydrogen co-firing ratio for each of the synchronous power supplies 21, ..., 2n to 0 during periods when hydrogen consumption exceeds hydrogen storage capacity. In this way, the system appropriately switches to operation using hydrocarbon fuels according to the amount of hydrogen stored.

[0076] Figure 7 is a flowchart of the processes performed by the processing unit of the energy management device (see also Figure 3 as appropriate). The series of processes shown in Figure 7 may be repeated at predetermined intervals, or they may be initiated by a predetermined input operation by an administrator. In step S101, the processing unit 12 reads various parameters and acquires various data. The parameters include the specifications of the synchronous power supplies 21, ..., 2n (see Figure 1) and renewable energy power supplies 31, ..., 3i, as well as the reference frequency, allowable frequency change rate, and fuel cost coefficients. The data acquired in step S101 also includes electricity demand forecast values ​​and renewable energy generation forecast values.

[0077] In step S102, the processing unit 12 calculates the target system inertia force (target system inertia force calculation process) and the target surplus power amount using the target system inertia force calculation unit 121. When calculating the target system inertia force and the target surplus power amount, the predicted power demand values ​​for each time period and the predicted renewable energy generation values ​​are used. Specifically, the target system inertia force is calculated based on equation (2) described above, and the target surplus power amount is calculated based on equation (3).

[0078] In step S103, the processing unit 12 calculates the target synchronous power generation amount using the power generation planning unit 122 (power generation planning process). Specifically, the processing unit 12 calculates the target synchronous power generation amount based on the power demand forecast value and renewable energy power generation forecast value included in the data acquired in step S101, as well as the target grid inertia force and target surplus power amount calculated in step S102. Specifically, the target synchronous power generation amounts for each synchronous power source 21, ..., 2n are calculated so as to satisfy the constraints of equations (6) and (7) described above, while minimizing the value of the objective function in equation (5).

[0079] In step S104, the processing unit 12 uses the hydrogen storage amount calculation unit 123 to calculate the total amount of hydrogen stored in the hydrogen storage devices 71, ..., 7i for each time period. Specifically, the calculation using equation (8) described above is performed based on the target surplus electricity amount, as well as the previous values ​​of hydrogen consumption and hydrogen storage amount.

[0080] In step S105, the processing unit 12 calculates the target hydrogen co-firing ratio for each of the synchronous power supplies 21, ..., 2n using the hydrogen co-firing ratio planning unit 124. Details of the process in step S105 will be described later.

[0081] In step S106, the processing unit 12 outputs the calculation results to the synchronous power supplies 21, ..., 2n and the renewable energy power supplies 31, ..., 3i. Specifically, the processing unit 12 outputs command values ​​for the target synchronous power generation amount and target hydrogen co-firing ratio for each time period to the synchronous power supplies 21, ..., 2n. The processing unit 12 also outputs command values ​​for the target surplus power amount for each time period to the renewable energy power supplies 31, ..., 3i. After performing the processing in step S106, the processing unit 12 terminates the series of processes (END).

[0082] Figure 8 is a flowchart showing the details of the process in step S105 of Figure 7. In step S1051, the hydrogen co-firing ratio planning unit 124 determines whether the current hydrogen storage amount (at the initial date and time of the calculation period) is below a predetermined value. The predetermined value is a threshold that serves as a criterion for determining whether or not there will be a hydrogen shortage even if hydrogen-only combustion is performed during the predetermined calculation period, and is set in advance. For example, the predetermined value (hydrogen storage amount threshold) may be set to an amount equivalent to three times the average daily hydrogen consumption. In step S1051, if the current hydrogen storage amount is greater than the predetermined value (S1051: No), the hydrogen co-firing ratio planning unit 124 proceeds to step S1052.

[0083] In step S1052, the hydrogen co-firing ratio planning unit 124 sets the hydrogen co-firing ratio of the synchronous power supplies 21, ..., 2n (see Figure 1) to an upper limit. For example, the hydrogen co-firing ratio planning unit 124 sets the hydrogen co-firing ratio for each time period to the upper limit of 1 (hydrogen-only firing), regardless of the load factor of the synchronous power supplies 21, ..., 2n. That is, if the amount of hydrogen stored at the initial date and time of a predetermined calculation period is greater than a predetermined value (S1051: No), the hydrogen co-firing ratio planning unit 124 sets the hydrogen co-firing ratio to an upper limit for that calculation period. This makes it possible to minimize CO2 emissions when sufficient hydrogen is stored. After performing the process in step S1052, the hydrogen co-firing ratio planning unit 124 terminates the series of processes related to setting the hydrogen co-firing ratio (END).

[0084] Furthermore, if the current hydrogen storage amount is below a predetermined value in step S1051 (S1051: Yes), the hydrogen co-firing ratio planning unit 124 proceeds to step S1053. In step S1053, the hydrogen co-firing ratio planning unit 124 calculates the target synchronous power load ratio. That is, the hydrogen co-firing ratio planning unit 124 calculates the target synchronous power load ratio for the synchronous power sources 21, ..., 2n based on the calculation result of the power generation planning unit 122 (target synchronous power generation amount) and the above-mentioned equation (9).

[0085] In step S1054, the hydrogen co-firing ratio planning unit 124 calculates the hydrogen co-firing ratio of the synchronous power supplies 21, ..., 2n (see Figure 1) for each time period. That is, the hydrogen co-firing ratio planning unit 124 calculates the hydrogen co-firing ratio of the synchronous power supplies 21, ..., 2n for each time period based on the target synchronous power supply load factor, which is the calculation result in step S1053, and the data shown in Figure 6 (relationship between load factor and hydrogen co-firing ratio). As described above, the higher the load factor of the synchronous power supply (i.e., the target synchronous power supply load factor), the larger the hydrogen co-firing ratio of that synchronous power supply is set to.

[0086] In step S1055, the hydrogen co-firing ratio planning unit 124 calculates the total CO2 emissions of the synchronous power supplies 21, ..., 2n (see Figure 1). That is, the hydrogen co-firing ratio planning unit 124 calculates the total CO2 emissions based on the hydrogen co-firing ratio, which is the result of the calculation in step S1054, and the aforementioned equation (10).

[0087] In step S1056, the hydrogen co-firing ratio planning unit 124 determines whether the total CO2 emissions are less than or equal to a predetermined target CO2 emissions. If the total CO2 emissions are greater than the target CO2 emissions (S1056: No), the hydrogen co-firing ratio planning unit 124 proceeds to step S1057.

[0088] In step S1057, the hydrogen co-firing ratio planning unit 124 rearranges each time period included in the predetermined calculation period in descending order of hydrogen co-firing ratio, and preferentially increases the hydrogen co-firing ratio of the highest-ranking time period in this order by a predetermined value (for example, 5%). After performing the process in step S1057, the hydrogen co-firing ratio planning unit 124 returns to step S1055.

[0089] Thus, if the sum of CO2 emissions from multiple synchronous power sources 21, ..., 2n exceeds a predetermined target CO2 emission amount (S1056: No), the hydrogen co-firing ratio planning unit 124 repeats the process (S1057) of increasing the hydrogen co-firing ratio of the time period with the highest hydrogen co-firing ratio among multiple time periods that are elements of a predetermined calculation period by a predetermined value until the sum of CO2 emissions becomes less than or equal to the target CO2 emission amount.

[0090] Furthermore, if the hydrogen co-firing ratio in the time period with the highest ratio among the multiple time periods that are elements of the calculation period has reached its upper limit, the hydrogen co-firing ratio planning unit 124 repeats the process of increasing the hydrogen co-firing ratio in the time period with the next highest ratio by a predetermined value until the total CO2 emissions fall below the target CO2 emissions.

[0091] Furthermore, if the total CO2 emissions in step S1056 are less than or equal to the target CO2 emissions (S1056: Yes), the hydrogen co-firing ratio planning unit 124 proceeds to step S1058. In step S1058, the hydrogen co-firing ratio planning unit 124 calculates the hydrogen consumption for each time period. That is, the hydrogen co-firing ratio planning unit 124 calculates the hydrogen consumption for each time period by substituting the target synchronous power generation amount and the hydrogen co-firing ratio values ​​into the above-mentioned equation (11).

[0092] In step S1059, the hydrogen co-firing ratio planning unit 124 determines whether there is a period of time during the predetermined calculation period in which hydrogen consumption exceeds hydrogen storage capacity. If there is a period of time in step S1059 in which hydrogen consumption exceeds hydrogen storage capacity (S1059: Yes), the hydrogen co-firing ratio planning unit 124 proceeds to step S1060.

[0093] In step S1060, the hydrogen co-firing ratio planning unit 124 sets the hydrogen co-firing ratio to 0 for the time period when hydrogen consumption exceeds hydrogen storage capacity, and terminates the series of processes (END). Also, in step S1059, if there is no time period when hydrogen consumption exceeds hydrogen storage capacity (S1059: No), the hydrogen co-firing ratio planning unit 124 terminates the series of processes (END).

[0094] Figure 9 shows an example of calculation results regarding the operation plan for synchronous power supplies and renewable energy power supplies. The horizontal axis in Figure 9 represents time. More specifically, the 24-hour period from 6:00 AM on the current day to 6:00 AM the following day is set as the predetermined calculation period. The vertical axis in Figure 9, from top to bottom, shows power, renewable energy ratio, target grid inertia force, target number of synchronous power sources in operation, target synchronous power source load factor, hydrogen co-firing ratio, synchronous power source thermal efficiency, hydrogen storage amount, and integrated CO2 emissions.

[0095] Furthermore, the power graph at the top of Figure 9 shows the predicted amount of renewable energy power generation, the predicted amount of electricity demand, and the target amount of synchronous power generation. Note that the renewable energy power generation amount is shown stacked on top of the synchronous power generation amount. The surplus power shown in Figure 9 is the value obtained by subtracting the sum of the renewable energy power generation amount and the synchronous power generation amount from the electricity demand. Also, in Figure 9, in the graphs for hydrogen co-firing ratio, synchronous power thermal efficiency, hydrogen storage amount, and integrated CO2 emissions, the values ​​corresponding to this embodiment are shown with solid lines, while comparative examples are shown with dashed lines.

[0096] As shown in Figure 9, the target grid inertia force is increased during daytime hours when the renewable energy ratio increases. Accordingly, the grid inertia force is ensured by increasing the number of synchronous power supplies in operation. Note that the more synchronous power supplies in operation there are, the lower the load factor per synchronous power supply (target synchronous power supply load factor). In the comparative example (dashed line), the hydrogen co-firing ratio is set to 1 (i.e., hydrogen-only firing) so that the target hydrogen co-firing ratio achieves maximum thermal efficiency regardless of the synchronous power supply load factor.

[0097] In contrast, in this embodiment (solid line), the hydrogen co-firing ratio is set to increase as the target synchronous power load factor increases. For example, during periods when the target synchronous power load factor is low, as mentioned above, the thermal efficiency due to hydrogen co-firing decreases (see also Figure 5), and consequently the thermal efficiency of the synchronous power supply also decreases. Therefore, in this embodiment (solid line), the hydrogen co-firing ratio is set to a lower value. On the other hand, in the comparative example (dashed line), the hydrogen co-firing ratio is always 1, except for the period when the hydrogen storage amount is almost zero (12:00 to 13:00). As a result, hydrogen consumption is high, and the hydrogen storage amount is zero during some daytime hours and at night.

[0098] In particular, during nighttime hours, the number of operating synchronous power supplies decreases, resulting in a higher synchronous power supply load factor. This tends to lead to differences in thermal efficiency depending on the hydrogen co-firing ratio. In the comparative example (dashed line), the cumulative CO2 emissions are kept low during the daytime due to the high hydrogen co-firing ratio, but CO2 emissions increase significantly after the hydrogen storage amount reaches zero at night. In contrast, in this embodiment (solid line), hydrogen consumption is suppressed during the daytime when the synchronous power supply load factor is low, while the hydrogen co-firing ratio is set high at night when the synchronous power supply load factor is high. This allows for efficient use of hydrogen, thereby effectively reducing CO2 emissions.

[0099] According to this embodiment, in a power system G including renewable energy power sources 31, ..., 3i and synchronous power sources 21, ..., 2n capable of hydrogen co-firing, it is possible to ensure a balance between power supply and demand and stabilize the frequency. For example, even if a malfunction occurs in an external power system H (see Figure 1) and the power system G is electrically disconnected from the external power system H, the power system G can be stabilized by ensuring system inertia within the energy system 100 and maintaining a balance between supply and demand. In addition, hydrogen can be used efficiently by setting the hydrogen co-firing ratio based on the load factor of the synchronous power sources 21, ..., 2n. Therefore, CO2 emissions from the synchronous power sources 21, ..., 2n can be effectively reduced.

[0100] ≪Variations≫ Although embodiments of the energy management device 10 and energy management method related to this disclosure have been described above, the invention is not limited to these descriptions and various modifications can be made. For example, in the embodiment, a case in which a generator equipped with a turbine (not shown) or an engine (not shown) is used as the synchronous power supply 21, ..., 2n has been described, but it is not limited to this. That is, it is also possible to use a synchronous condenser for at least a part of the synchronous power supply 21, ..., 2n. In the synchronous condenser, the hydrogen co-firing ratio is appropriately adjusted to maintain a predetermined rotational speed. Furthermore, as will be explained below, grid inertia may be ensured by a pseudo-inertia inverter connected to the fuel cell.

[0101] Figure 10 is a configuration diagram including an energy management device 10A according to a modified example. In the modified example shown in Figure 10, the energy system 100A includes fuel cells 91,...,9n and pseudo-inertial force inverters 101,...,10n. The fuel cells 91,...,9n are batteries configured to extract electrical energy by reacting hydrogen and oxygen. Hydrogen is supplied to the fuel cells 91,...,9n from hydrogen storage devices 71,...,7i via a hydrogen supply line P. Incidentally, when electrolysis of water is performed in the hydrogen production devices 61,...,6i, oxygen is also produced along with hydrogen. This oxygen may be stored in an oxygen storage device (not shown) and further supplied to the fuel cells 91,...,9n via an oxygen supply line (not shown).

[0102] The pseudo-inertia inverters 101, ..., 10n (also called synchronous force inverters) shown in Figure 10 are configured to simulate the behavior of a synchronous power supply through inverter control and generate pseudo-system inertia and synchronous forces. Since the fuel cells 91, ..., 9n and pseudo-inertia inverters 101, ..., 10n are well known, a detailed explanation will be omitted. As shown in Figure 10, the fuel cell 91 is connected to the power transmission and distribution line L via the pseudo-inertia inverter 101. The connection between the fuel cell 91 and the pseudo-inertia inverter 101 constitutes a "synchronous power supply" (the same applies to the other fuel cells 9n and pseudo-inertia inverters 10n). In the configuration shown in Figure 10, the fuel used for power generation of the aforementioned "synchronous power supply" is assumed to include hydrogen produced by the power generated by the renewable energy power sources 31, ..., 3i.

[0103] Figure 11 is a functional block diagram of the modified energy management device 10A. The processing unit 12A of the energy management device 10A shown in Figure 11 is configured to include a hydrogen usage planning unit 126 instead of the hydrogen co-firing ratio planning unit 124 (see Figure 3) described in the embodiment. The hydrogen usage planning unit 126 calculates the target amount of hydrogen to be used in the fuel cells 91,...,9n based on the target synchronous power generation amount and the hydrogen storage amount. That is, the hydrogen usage planning unit 126 calculates the target amount of hydrogen for each time period so that a predetermined target synchronous power generation amount (the target value of the amount of power generated in each fuel cell 91,...,9n) is met and the hydrogen storage amount does not become zero. The calculation results of the hydrogen usage planning unit 126 are output to the control devices (not shown) of the fuel cells 91,...,9n. Incidentally, since the volume ratio of hydrogen to oxygen consumed in the fuel cells 91,...,9n is 2:1, the target amount of oxygen is also determined according to the target amount of hydrogen.

[0104] Furthermore, although the embodiment described a case in which multiple synchronous power supplies 21, ..., 2n (see Figure 1) and multiple renewable energy power supplies 31, ..., 3i (see Figure 1) are included in the power system G, it is not limited to this. For example, the number of synchronous power supplies and renewable energy power supplies included in the power system G may be just one. In addition to synchronous power sources 21, ..., 2n (see Figure 1) and renewable energy power sources 31, ..., 3i, other power plants such as thermal power plants (not shown) and nuclear power plants (not shown) may also be connected to the transmission and distribution line L (see Figure 1).

[0105] Furthermore, the processing (energy management method) of the energy management device 10 may be executed as a predetermined program on a computer. The aforementioned program can be provided via a communication line, or it can be written to a recording medium such as a CD-ROM and distributed.

[0106] Furthermore, this disclosure is not limited to the embodiments and includes various modifications. For example, the embodiments are described in detail for the purpose of clearly illustrating this disclosure and are not necessarily limited to having all the configurations described. Also, some of the configurations of the embodiments can be added, deleted, or replaced with other configurations.

[0107] Furthermore, each of the aforementioned configurations, functions, processing units, processing means, etc., may be implemented in hardware, either partially or entirely, by designing them as integrated circuits, for example. Alternatively, each of the aforementioned configurations, functions, etc., may be implemented in software by having the processor interpret and execute programs that realize each function. Information such as programs, tables, and files that realize each function can be stored in memory, a recording device such as a hard disk or SSD (Solid State Drive), or a recording medium such as an IC card, SD card, or DVD.

[0108] Furthermore, the control lines and information lines shown are those deemed necessary for explanatory purposes, and not all control lines and information lines are necessarily shown in the actual product. In reality, it can be assumed that almost all components are interconnected. [Explanation of Symbols]

[0109] 10,10A Energy Management Device 11 Storage section 12,12A Processing Unit 21,…,2n synchronous power supply 31,…,3i Renewable Energy Power 41,…,4i Inverter 50 Circuit breakers 61,…,6i Hydrogen production equipment 71, ..., 7i Hydrogen storage device 81,…,8k Consumer 91,…,9n Fuel cell (synchronous power supply) 100,100A Energy System 10¹, ..., 10¹N Simulated Inertia Inverter (Synchronous Power Supply) 121 Target system inertia force calculation section 122 Power Generation Planning Department 123 Hydrogen Storage Amount Calculation Unit 124 Hydrogen Co-firing Ratio Planning Department 125 Previous value retention section 126 Hydrogen Use Planning Department G Power system S102 Step (Target System Inertial Force Calculation Processing) S103 Step (Power generation planning processing)

Claims

1. The system includes a target system inertia calculation unit that calculates a target surplus electricity amount, which is the portion of the renewable energy power generation used for hydrogen production, based on a predicted electricity demand value for the power grid including renewable energy power sources and synchronous power sources, and a predicted renewable energy power generation value, which is the predicted power generation amount of the renewable energy power sources, and also calculates a target system inertia force for the power grid. The fuel used for generating electricity in the aforementioned synchronous power supply includes hydrogen produced by the electricity generated by the aforementioned renewable energy power supply. An energy management device further comprising a power generation planning unit that calculates a target synchronous power generation amount, which is a target value for the amount of power generated by the synchronous power source during each time period, based on the predicted power demand value, the predicted renewable energy generation amount, the target surplus power amount, and the target grid inertia force.

2. A hydrogen storage amount calculation unit calculates the amount of hydrogen stored in each time period based on the amount of hydrogen consumed when hydrogen produced by the electricity generated by the renewable energy power source is co-fired with hydrocarbon fuel to be used as fuel for the synchronous power source, and the target surplus electricity amount. The system includes a hydrogen co-firing ratio planning unit that calculates the hydrogen co-firing ratio in the synchronous power supply based on the target synchronous power supply generation amount and the hydrogen storage amount. The energy management device according to claim 1, characterized by the following:

3. The target system inertia force calculation unit calculates the power fluctuation rate of the power system based on the renewable energy ratio, which is the ratio of the predicted renewable energy generation amount to the predicted power demand amount, and further calculates the target system inertia force based on the power fluctuation rate and the predicted power demand amount. The energy management device according to claim 1, characterized by the following:

4. The target system inertia force calculation unit allocates the surplus amount when the renewable energy ratio, which is the ratio of the predicted renewable energy generation amount to the predicted electricity demand amount, exceeds a predetermined upper limit, as the target surplus electricity amount for hydrogen production. The energy management device according to claim 1, characterized by the following:

5. The target system inertia force calculation unit, when producing hydrogen with the power generated by the renewable energy source, prioritizes the use of hydrogen production equipment connected to hydrogen storage equipment with a relatively small hydrogen storage capacity over other hydrogen production equipment. The energy management device according to claim 1, characterized by the following:

6. The power generation planning unit calculates the target synchronous power generation amount for each time period of the multiple synchronous power sources in order to minimize the cost required to operate the synchronous power sources, under the constraints of a first constraint that the sum of the inertial constants of each of the multiple synchronous power sources is equal to or greater than the target system inertial force, and a second constraint that the balance of power supply and demand is maintained in the power system. The energy management device according to claim 1, characterized by the following:

7. The hydrogen co-firing ratio planning unit calculates the hydrogen co-firing ratio based on the relationship between the load factor of the synchronous power supply and the increase ratio of the thermal efficiency of the synchronous power supply. The energy management device according to claim 2, characterized by the following:

8. The hydrogen co-firing ratio planning unit increases the hydrogen co-firing ratio of the synchronous power supply as the load factor of the synchronous power supply increases. The energy management device according to claim 2, characterized by the following:

9. The hydrogen co-firing ratio planning unit controls the CO2 in multiple synchronous power supplies. ２ The total amount of emissions is the predetermined target CO2 ２ The hydrogen co-firing ratio is calculated so as to be less than or equal to the emissions. The energy management device according to claim 2, characterized by the following:

10. The hydrogen co-firing ratio planning unit controls the CO2 in multiple synchronous power supplies. ２ The total amount of emissions is the predetermined target CO2 ２ If the emissions exceed the limit, the process of increasing the hydrogen co-firing ratio in the time period with the highest hydrogen co-firing ratio among multiple time periods that are elements of a predetermined calculation period by a predetermined value is performed, the CO ２ The total amount of emissions is the aforementioned target CO2 ２ Repeat until the amount of emissions is less than or equal to the amount of emissions. The energy management device according to claim 2, characterized by the following:

11. The hydrogen co-firing ratio planning unit, when the hydrogen co-firing ratio in the time period with the highest hydrogen co-firing ratio among the multiple time periods that are elements of the calculation target period has reached its upper limit, performs a process to increase the hydrogen co-firing ratio in the time period with the next highest hydrogen co-firing ratio by a predetermined value, the CO ２ The total amount of emissions is the aforementioned target CO2 ２ Repeat until the amount of emissions is less than or equal to the amount of emissions. The energy management device according to claim 10, characterized by the following:

12. The hydrogen co-firing ratio planning unit sets the hydrogen co-firing ratio to an upper limit for the calculation period if the amount of hydrogen stored at the initial date and time of a predetermined calculation period is greater than a predetermined value. The energy management device according to claim 2, characterized by the following:

13. The system includes a target system inertia calculation process that calculates a target amount of surplus electricity, which is the portion of the renewable energy power generation used for hydrogen production, based on a predicted electricity demand value for the power grid including renewable energy power sources and synchronous power sources, and a predicted renewable energy power generation value, which is the predicted power generation amount of the renewable energy power sources, and also calculates a target system inertia force for the power grid. The fuel used for generating electricity in the aforementioned synchronous power supply includes hydrogen produced by the electricity generated by the aforementioned renewable energy power supply. An energy management method further comprising a power generation planning process that calculates a target synchronous power generation amount, which is a target value for the amount of power generated at each time period of the synchronous power source, based on the predicted power demand value, the predicted renewable energy generation amount, the target surplus power amount, and the target grid inertia force.

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