Control methods, programs, and energy management systems

Abstract

This system enables energy management that automatically creates an economically efficient operating schedule for energy storage devices, taking into account electricity procurement costs. [Solution] Customer 5 is equipped with an electrical load 25, a solar power generation device 50, and energy storage devices 20, 30, and is capable of buying and selling electricity to and from the power grid 3. Server 10 creates an operation schedule for the energy storage devices 30, 40 for the next day based on the power procurement unit price for each of several time slots that divide the next day's 24 hours, the predicted power generation amount by the solar cells 50 and the predicted power consumption amount of customer 5 for each of the multiple time slots, and the comparison and determination result of the power procurement unit price and determination threshold in the time slot group that includes the default operating candidate period for the energy storage devices 30, 40 among the multiple time slots. HEMS 20 generates operation commands for the energy storage devices 30, 40 according to the operation schedule created by Server 10.

Description

Technical Field

[0001] The present disclosure relates to energy management for consumers equipped with a device (hereinafter also referred to as an "energy storage device") that directly or indirectly stores electrical energy generated by a photovoltaic power generation device, such as a storage battery and an electric water heater of a hot water storage type.

Background Art

[0002] In consumers where photovoltaic power generation is introduced, depending on the arrangement of the energy storage device, it becomes possible to shift the usage period of the energy generated by photovoltaic power generation from the actual power generation period. For this reason, energy management for creating a power usage schedule to improve the energy usage efficiency has been introduced by means of a HEMS (Home Energy Management System) or the like.

[0003] Also, in recent years, the Japan Electric Power Exchange (JEPX) sets the power procurement price for the next day for each 30-minute time zone at a predetermined time every day, so the electricity unit price fluctuates daily.

[0004] In relation to this point, Japanese Patent Application Laid-Open No. 2022-184742 (Patent Document 1) discloses a technique for determining a period for requesting a consumer to adjust the power usage amount based on the prediction result of the transition of the power procurement unit price provided only for the next day and providing it to the user.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] According to Patent Document 1, providing forecast information on electricity procurement unit prices for the following day and beyond is expected to improve economic efficiency by making it easier for users to plan the long-term use of loads such as electric vehicles and storage batteries.

[0007] In particular, adjusting the operating timing of energy storage devices in response to fluctuations in electricity procurement prices will reduce electricity retailers' electricity procurement costs. This cost benefit will then be used to provide economic benefits to users, thereby improving overall economic efficiency for both consumers and electricity retailers.

[0008] However, in the technology described in Patent Document 1, the user directly determines the timing of load operation, and therefore, it is up to the user whether or not economically efficient scheduling that responds to fluctuations in electricity prices is achieved. For this reason, there are doubts about the certainty that the effect of improving economic efficiency will be obtained.

[0009] This disclosure was made to address these issues, and its purpose is to realize energy management that automatically creates an operating schedule for energy storage systems that is economically efficient for both consumers and electricity retailers as a whole, by taking into account electricity procurement costs, for consumers equipped with solar power generation systems and energy storage systems. [Means for solving the problem]

[0010] In certain aspects of this disclosure, a control method for energy management is provided. Energy management is intended for consumers who are able to buy and sell electricity to and from the power grid, and who have electrical loads, photovoltaic power generation equipment and energy storage equipment installed. The control method comprises (a) obtaining the power procurement unit price of the power grid for each of several time slots that divide the next day's 24 hours; (b) obtaining for each of the several time slots the predicted PV generation amount from the photovoltaic power generation equipment based on the next day's weather forecast information and the predicted amount of electricity used by the consumer based on past actual values ​​of electricity used by the consumer; (c) comparing the power procurement unit price in a group of time slots that belong to a predetermined time period that includes the default operating candidate period of the energy storage equipment with a predetermined judgment threshold; and (d) creating an operating schedule for the next day of the energy storage equipment based on the predicted PV generation amount, predicted amount of electricity used, and the results of the comparison judgment.

[0011] In other aspects of this disclosure, a program is provided. When the program is executed by multiple processors, it causes one or more processors to perform the control method described above.

[0012] In yet another aspect of this disclosure, an energy management system is provided. The energy management system manages consumers who are able to buy and sell electricity to and from the power grid, where electrical loads, photovoltaic power generation equipment and energy storage equipment are located. The energy management system comprises a higher-level control unit that creates an operating schedule for the consumer's energy storage equipment, and a control unit located at the consumer that generates operating commands for the energy storage equipment according to the operating schedule created by the higher-level control unit. The higher-level control unit includes means for obtaining the power procurement unit price of the power grid for each of several time slots that divide the following 24 hours, means for obtaining, for each of the several time slots, the predicted PV power generation amount from the photovoltaic power generation equipment based on the following day's weather forecast information and the predicted amount of electricity used by the consumer based on past actual values ​​of electricity used, means for performing a comparison determination between the power procurement unit price in a group of time slots that belong to a predetermined time period that includes the default operating candidate period of the energy storage equipment, and a predetermined determination threshold, and means for creating an operating schedule for the energy storage equipment for the following day based on the predicted PV power generation amount, the predicted amount of electricity used, and the results of the comparison determination. [Effects of the Invention]

[0013] According to this disclosure, it is possible to realize energy management that automatically creates an economically efficient operating schedule for energy storage devices, taking into account electricity procurement costs. [Brief explanation of the drawing]

[0014] [Figure 1] This is a conceptual diagram illustrating an example configuration of the energy management system according to this embodiment. [Figure 2] Figure 1 is a block diagram schematically showing an example of the server hardware configuration. [Figure 3] This is a conceptual diagram to explain EQ daytime shift control. [Figure 4] This is a conceptual diagram to explain discharge timing control. [Figure 5] This is a conceptual diagram illustrating the outline of the battery operation schedule according to the energy management system of this embodiment. [Figure 6] It is a conceptual diagram for explaining the charging pattern of a storage battery by energy management according to the present embodiment. [Figure 7] It is a flowchart for explaining the operation schedule creation process according to the energy management according to the present embodiment. [Figure 8] It is a chart for explaining an example of the configuration data of the operation schedule formulated by the process of FIG. 7. [Figure 9] It is a flowchart for explaining the details of the EQ daytime shift control process shown in FIG. 7. [Figure 10] It is a conceptual diagram for explaining the image of the necessity determination of EQ daytime shift control. [Figure 11] It is a first flowchart for explaining the details of the discharge plan process shown in FIG. 7. [Figure 12] It is a second flowchart for explaining the details of the discharge plan process shown in FIG. 7. [Figure 13] It is a flowchart for explaining the details of the charge plan process shown in FIG. 7. [Figure 14] It is a first flowchart for explaining the details of the value difference charge control process shown in FIG. 13. [Figure 15] It is a second flowchart for explaining the details of the value difference charge control process shown in FIG. 13. [Figure 16] It is a first flowchart for explaining the details of the FIT charge control process shown in FIG. 13. [Figure 17] It is a second flowchart for explaining the details of the FIT charge control process shown in FIG. 13. <- [Figure 18] It is a flowchart for explaining the details of the morning control process shown in FIG.. [Figure 19] It is a chart for explaining the pattern classification of the creation result of the operation schedule created by the processes of FIGS. 7 to 18. [Figure 20] It is a functional block diagram for explaining the energy management according to the present embodiment.

Mode for Carrying Out the Invention

[0015] Embodiments of this disclosure will be described in detail below with reference to the drawings. In the following, the same or corresponding parts in the drawings will be denoted by the same reference numerals, and their descriptions will not be repeated in principle.

[0016] <System Configuration> Figure 1 is a conceptual diagram illustrating an example configuration of the energy management system 100 according to this embodiment.

[0017] As shown in Figure 1, the energy management system 100 comprises a customer 5 to be managed and a server 10. Customer 5 is equipped with a HEMS 20, an electrical load 25, a solar cell 50 which is an example of a "solar power generation device", and a storage-type electric water heater 30 and a storage battery 40 which are shown as representative examples of an "energy storage device". Typically, an EcoCute (registered trademark) can be used as this electric water heater 30, so below, the electric water heater 30 will also be referred to as EcoCute 30. Customer 5 is equipped with a meter 60 (for example, a smart meter) for measuring electricity usage. The values ​​measured by the meter 60 are transmitted to the HEMS 20 via communication. This allows the HEMS 20 to obtain the amount of electricity used at customer 5 for each time period (each time slot).

[0018] Customer 5 can exchange AC (alternating current) power with the power grid 3. Furthermore, the solar cell 50 can supply AC power equivalent to that of the power grid 3 (hereinafter also simply referred to as "PV power") via a power conditioner (not shown). PV power can be used for both the electricity consumed by customer 5 (electrical load 25 and EcoCute 30) and the charging power of the storage battery 40. In addition, any surplus PV power relative to customer 5's electricity consumption can be sold to the power grid 3 at a predetermined electricity price (selling price).

[0019] The battery 40 can be charged using either electricity purchased from the power grid 3 (purchased electricity) or PV electricity via a charge / discharge controller (not shown). Furthermore, the charge / discharge controller can convert the DC (direct current) electricity discharged from the battery 40 into AC electricity equivalent to that of the power grid 3 (hereinafter also simply referred to as "discharged electricity"). Therefore, the electrical load 25 and the EcoCute 30 can operate using either the purchased electricity from the power grid 3, PV electricity, or the discharged electricity from the battery 40.

[0020] The charging and discharging of the battery 40 is performed by the operation of the charge / discharge controller described above in accordance with the operation commands from the HEMS 20 (grid charging / automatic (discharge / PV surplus charging) / charge / discharge stop). This allows the charging or discharging of the battery 40, and the amount of power consumed during charging or discharging, to be controlled according to the operation commands from the HEMS 20.

[0021] The EcoCute 30 operates at the timing specified by the operation command from the HEMS 20 and can perform a hot water storage operation (hereinafter also referred to as "EQ hot water storage operation") in which it heats tap water or the like and stores the resulting high-temperature water in a hot water storage tank (not shown).

[0022] The EcoCute 30 can operate to use the high-temperature water stored in the hot water storage tank through the EQ water heating operation for purposes such as filling a bathtub (not shown) and supplying hot water from a hot water tap (not shown).

[0023] Server 10 communicates with HEMS 20 via a communication network 2, such as the Internet. Furthermore, Server 10 communicates with other server groups 9 via the communication network 2. Server group 9 includes Server 9X (for example, a weather company's server) which provides forecast data for PV power generation by solar cells 50, and Server 9Y which provides information indicating JEPX unit prices.

[0024] In this embodiment, by pre-registering solar cell information for each customer 5 (installation location information (latitude and longitude), number of panels, panel installation direction, and panel installation angle for each solar cell 50) with a weather company, the server 9X provides predicted PV power generation (kWh) information for each of the 48 30-minute segments of the 24 hours from 0:00 to 24:00 the following day, based on the predicted sunshine amount data for the next day and the said solar cell information. The PV power generation for each segment is obtained by accumulating the predicted PV power generation values ​​over 30 minutes. Alternatively, as a modification, the PV power generation (predicted value) for each segment can also be calculated by calculation on the server 10 using information from the server 9X (for example, only the sunshine amount prediction data). The method for predicting PV power generation is arbitrary, and it is possible to apply AI (Artificial Intelligence), etc.

[0025] Server 10 can use information from Server 9Y to obtain the power procurement unit price (hereinafter referred to as "JPEX unit price") for each of the 48 power grids mentioned above, as determined by the Japan Electric Power Exchange.

[0026] Furthermore, the server 10 can periodically collect actual data from the HEMS 20, which receives the measurement values ​​from the meter 60, including the amount of electricity used, PV power, discharge power and charging power of the battery 40 for each time period (each time slot) for each of the 5 consumers. The server 10 has a function to predict the amount of electricity used (kWh) for each time slot the following day using past actual data through predictive calculations that apply AI (Artificial Intelligence), etc. Alternatively, this prediction function may be provided in an external device of the server 10. In this case, the server 10 can obtain the predicted results of the amount of electricity consumed (kWh) for each time slot from the external device via the communication network 2, etc.

[0027] In Figure 1, an example is shown in which Server 10, each server in Server Group 9, and HEMS 20 are connected by a common communication network 2. However, at least a portion of the communication between these devices may be conducted via dedicated lines.

[0028] In this embodiment, we will describe an example in which, as the simplest configuration, the server 10 uses various performance data from each customer 5 collected via the HEMS 20 and information obtained from other companies' server group 9 to create an operating schedule for the energy storage device (EcoCute 30 and battery 40) of each customer 5, and the HEMS 20 generates operation commands for the energy storage device (EcoCute 30 and battery 40) according to the operating schedule sent to the customer 5 from the server 10. That is, in the following description, the server 10 corresponds to an embodiment of a "higher-level control device" that creates an operating schedule, and the HEMS 20 corresponds to an embodiment of a "control device" that generates operation commands according to the operating schedule.

[0029] However, the control method for creating an operating schedule for energy management according to this embodiment is not limited to a case where it is executed only by the processors constituting the server 10, but can also be executed in a distributed configuration by further using processors constituting other servers and / or HEMS 20, etc.

[0030] The following describes how to create an operating schedule for energy management for a customer 5 equipped with both an EcoCute 30 and a battery 40 as energy storage devices. However, as will be explained later, the energy management according to this embodiment can also be applied to a customer 5 equipped with only one of the EcoCute 30 or the battery 40.

[0031] <Example Hardware Configuration> Figure 2 is a block diagram schematically showing an example of the hardware configuration of server 10 shown in Figure 1.

[0032] As shown in Figure 2, the server 10 includes, as its main components, a processor 11 such as a CPU (Central Processing Unit) that executes programs, a first memory 12, and a second memory 13. The first memory 12 can be composed of ROM (Read Only Memory) that non-volatilely stores data and programs. The second memory 13 includes a work area when the processor 11 executes programs, as well as an area that volatilely stores data generated by program execution or input data. The second memory 13 is composed of RAM (Random Access Memory).

[0033] Furthermore, the server 10 includes a communication interface (I / F) 14, an input device 15 for receiving operations on the server 10, a display 16 for displaying information, a timer 17 with a time detection function, and an I / O (Input / Output) unit 18 for connecting external devices in a communicative manner. These components are interconnected by a data bus and are powered by a power supply circuit (not shown). The communication interface 14 also includes an interface circuit for controlling communication between the communication network 2 and the server 10, or between the server 10 and other devices on a dedicated line as described above.

[0034] Processing in server 10 is realized by software (programs) executed by each piece of hardware and processor 11. For example, such software is pre-stored in first memory 12. Alternatively, the software may be provided as a downloadable program product by an information provider connected to the so-called Internet. Such software can be downloaded via communication I / F 14 and then stored in first memory 12. Alternatively, the software may be stored in a storage medium (not shown) and read from that storage medium to be stored in first memory 12.

[0035] These software files are read from the first memory 12 by the processor 11 and expanded into the second memory 13 in the form of an executable program. By executing this program, the processor 11 can perform the creation of a schedule for energy management control (described below).

[0036] For HEMS20, it is possible to apply the same hardware configuration example as for server 10 shown in Figure 2. However, in order to enhance the user interface functionality, it is preferable to configure the display 16 as a touch panel, so that at least a portion of the input device 15 is configured as touch switches displayed on the display 16. In addition, the input device 15 and display 16 as the user interface in HEMS20 may be configured as a mobile terminal such as a smartphone with predetermined application software installed.

[0037] <Description of energy management in this embodiment> Next, using Figures 3 to 6, we will explain the overview of the energy management system in this embodiment that reflects the JEPX unit price.

[0038] Figure 3 is a conceptual diagram illustrating EQ daytime shift control, which shifts the operating time of an EcoCute water heater. In Figure 3, the horizontal axis represents time, and the vertical axis represents power (kW). Therefore, the area (time × power) represents the amount of energy (kWh).

[0039] Figure 3(a) schematically shows a typical operating schedule for the EcoCute 30 as a comparative example. In contrast, Figure 3(b) schematically shows the EQ daytime shift control in this embodiment.

[0040] As shown in Figures 3(a) and 3(b), the EQ water heating operation generates high-temperature water by heating low-temperature water such as tap water using a heat pump that consumes electricity over multiple time slots (30-minute intervals), and stores the high-temperature water in a hot water storage tank (not shown).

[0041] As shown in Figure 3(a), in the comparative example, the nighttime operating period (for example, 0:00 to 6:00) is set in advance to include the late-night period, and the EQ water heating operation is performed continuously every day during this period using purchased electricity. For example, customer 5 can improve its economic efficiency by contracting for cheaper nighttime electricity. Also, the power grid 3 (electricity retailer) benefits from increasing electricity demand during the nighttime period in terms of power supply efficiency. The EcoCute 30 can use the high-temperature water stored during the nighttime period to meet hot water demand in the morning, afternoon, and evening, such as filling bathtubs or drawing hot water from taps.

[0042] During daytime hours, PV power generated by solar panels 50, depending on the amount of sunlight, can be used to meet the electricity needs of customer 5. If electricity consumption exceeds PV power, the shortfall is covered by electricity purchased from the power grid 3. On the other hand, if PV power exceeds electricity consumption and a surplus is generated, the surplus can be sold to the power grid 3 at a pre-contracted selling price.

[0043] Here, if we define "PV surplus power (kW)" as the difference between the PV power generated by the solar panel 50 and the power used by the consumer 5, then a positive value for PV surplus power means that there is surplus power to sell. When the subtraction value is negative, PV surplus power is considered to be "0". Therefore, the minimum value of PV surplus power at each point in time is 0, and the maximum value is the PV power. By accumulating the PV surplus power in units of 30 minutes, the amount of PV surplus power (kWh) for each unit can be obtained. Furthermore, PV surplus power can be used not only for selling electricity but also for charging the storage battery 40.

[0044] As shown in Figure 3(b), when there is abundant sunlight, it is sometimes possible to secure the power needed for EQ water heating operation using surplus PV power during the day. In this case, by shifting the execution time of EQ water heating operation from the aforementioned nighttime operating period to the daytime, it is possible to avoid purchasing electricity from power grid 3. Furthermore, by performing EQ water heating operation during the day, it is generally expected that the time required to store high-temperature water before bath use will be shortened, thereby improving energy efficiency and economic efficiency. In EQ daytime shift control, the nighttime operating period corresponds to the "candidate operating period" of the energy storage device and the "default candidate water heating period" of the EcoCute 30 (storage-type electric water heater).

[0045] On the other hand, if the EQ water heating operation is performed during the daytime, the amount of surplus PV electricity during the daytime, i.e., the amount of electricity sold, will decrease. Therefore, in general terms, using a fixed electricity selling price and the JEPX price which fluctuates daily according to market supply and demand, it is possible to determine whether or not to shift the EcoCute 30's EQ water heating operation to daytime before midnight. At this time, the condition for determining whether or not to shift to daytime can also be included in the decision-making process whether or not to shift to daytime, based on the sunshine amount forecast data from the next day's weather forecast, and whether or not there will be enough surplus PV electricity to cover the power consumption of the EQ water heating operation in the time slot group expected to be the shift destination.

[0046] If a daytime shift is deemed "required," the EQ water heating operation will not be performed during the late-night hours after midnight the following day, as indicated by the dotted line in the diagram. On the other hand, if a daytime shift is deemed "not required," the EQ water heating operation will be performed during the late-night hours after midnight the following day, as shown in Figure 3(a).

[0047] Figure 4 is a conceptual diagram illustrating the discharge timing control of the battery 40. The horizontal axis in Figure 4 is the time axis, indicating the passage of time.

[0048] Figure 4(a) shows a comparative example of discharge timing control. In this comparative example, the JEPX unit price is not considered, and the discharge timing of the battery 40 is determined in conjunction with the trend of surplus PV power.

[0049] PV surplus power (kW) is positive during daytime hours when sunlight is present and decreases in the evening. In the example in Figure 4(a), daytime PV surplus power is used to charge the battery 40, and the remaining BAT amount (kWh), which indicates the remaining charge of the battery 40, increases. After the BAT amount reaches the full charge level (equivalent to the rated capacity), the PV surplus power can be used to sell electricity to the power grid 3. The BAT amount can also be expressed as a percentage (%) of the current remaining charge relative to the rated capacity (kWh) of the battery 40. Furthermore, when the PV surplus power exceeds the maximum charging power (kWh) of the battery 40, the excess amount can be used to sell electricity to the power grid 3 regardless of the BAT amount.

[0050] As sunlight decreases, when the surplus PV power reaches zero at time t0 in the evening, the electricity used by customer 5 is supplied by discharge from the storage battery 40 instead of PV power. Therefore, the remaining battery capacity gradually decreases after time t0. In other words, from a power management perspective, time t0 corresponds to the "end of power generation" for the solar cells 50.

[0051] At time t1, when the remaining BAT level drops to 0 (or the lower limit), discharge from battery 40 is terminated. After time t1, the power used by electrical load 25 is secured by electricity purchased from power grid 3, so purchased power (kW) is generated.

[0052] On the other hand, the JPEX price rises from time t2 onward compared to before time t2, in response to increased electricity demand at night. As a result, in the comparative example in Figure 4(a), where the discharge timing of the battery 40 is determined without considering the JEPX price, it can be seen that electricity may be purchased from the power grid 3 in a concentrated manner during periods when the JEPX price is high.

[0053] Figure 4(b) shows a comparative example of discharge timing control according to this embodiment. The horizontal axis in Figure 4(b) is also the time axis, and the vertical axis shows the same quantities as in Figure 4(a).

[0054] In Figure 4(b), the waveform of the PV surplus power is the same as in Figure 4(a), and the PV surplus power becomes 0 after time t0. Therefore, the waveform of the remaining BAT up to time t0 is also the same as in Figure 4(a).

[0055] In the discharge timing control shown in Figure 4(b), the discharge timing of the battery 40 after time t0 is determined considering the JEPX unit price. For example, similar to Figure 4(a), assuming a case where the JEPX unit price is set high during the time period t2 to t4, which is the peak of nighttime demand, the battery 40 is not discharged between t0 and t2, and priority is given to purchasing electricity from the power grid 3.

[0056] Then, at time t2, when the JEPX unit price rises, the battery 40 begins to discharge, and from time t2 onward, the remaining BAT capacity decreases due to the discharge of battery 40. At time t3, when the remaining BAT capacity falls to the same level as at time t1 in Figure 4(a), the discharge from battery 40 ends. From time t3 onward, the power used by consumer 5 is secured by purchasing electricity from power grid 3, so purchased electricity (kW) is generated.

[0057] As a result, with the discharge timing control shown in Figure 4(b), compared to Figure 4(a), the procurement cost of electricity purchased by customer 5 can be reduced due to the difference in JEPX unit prices for the same amount of electricity consumed by customer 5.

[0058] Figure 5 shows a conceptual diagram illustrating the outline of the operating schedule created by the energy management system according to this embodiment.

[0059] Referring to Figure 5, in this embodiment, the process of creating the next day's operation schedule is executed at a predetermined timing before midnight (for example, 10pm). As a result, in the case of customer 5 illustrated in Figure 1, the operation schedule for the EcoCute 30 (EQ water heating time slot) and the operation schedule for the storage battery 40 (charge / discharge schedule) are created.

[0060] The battery 40 can be charged primarily by electricity purchased during nighttime hours (hereinafter also referred to as "grid charging") and by surplus PV power during daytime hours. However, the charging timing is controlled to maximize economic efficiency, taking into account the JEPX unit price. On the other hand, the discharge timing of the battery 40 is controlled, as explained in Figure 4(b), taking into account the JEPX unit price.

[0061] Furthermore, by considering the predicted remaining capacity W1 [kWh] of the battery 40 at the end of solar power generation on the following day (corresponding to time t0 in Figure 4) and the required remaining battery capacity W0 [kWh] at the end of solar power generation on the following day, which is determined from the total amount of electricity discharged from the battery 40 on the following day according to the discharge plan based on the discharge timing control described above, an operating schedule for the battery 40 can be created.

[0062] The predicted remaining charge W1 [kWh] can be calculated by adding the battery charge Wa [kWh] at midnight the following day and the surplus PV power Wb [kWh] (total value) during the daytime the following day. The battery charge Wa can be set using the battery charge (kWh) at the time of creating the operation schedule, or by combining it with further prediction calculations up to midnight the following day.

[0063] As will be described later, the operating schedule for the battery 40 determines whether charging or discharging is necessary for each 30-minute time slot, and the amount of charging energy (kWh) or discharging energy (kWh) for that time slot.

[0064] Figure 6 is a conceptual diagram illustrating the battery charging pattern using energy management according to this embodiment. As a result of the battery 40 operating according to the operating schedule created in Figure 5, the battery charging pattern will be one of the patterns shown in Figures 6(a) to (d).

[0065] In general terms, one of the charging patterns shown in Figures 6(a) to (d) is selected based on the relative magnitudes of the predicted remaining charge value W1 [kWh] and the required remaining charge value W0 [kWh] of the battery 40, as well as the JEPX unit price during the default candidate time period for grid charging (for example, 0:00 to 8:00, hereinafter referred to as the "grid charging time period"). The grid charging time period corresponds to the "candidate operating period" of the energy storage device and the "default candidate charging period" of the battery 40.

[0066] In this embodiment, when the JEPX unit price is low during grid charging hours, FIT (Feed-in Tariff) charging as shown in Figure 6(a) or differential charging as shown in Figure 6(b) is applied, while when the JEPX unit price is not low during grid charging hours, the green mode as shown in Figure 6(c) or PV surplus charging as shown in Figure 6(d) is applied, thereby improving economic efficiency.

[0067] The FIT charging method shown in Figure 6(a) is selected when the predicted remaining battery capacity W1 is higher than the required remaining battery capacity W0 (W1 > W0), there is surplus power sales capacity during the daytime on the following day, and the JEPX unit price is low during grid charging hours.

[0068] In FIT charging, during grid charging hours, grid charging of battery 40 using purchased electricity is performed, up to the required battery charge value W0. During the daytime, surplus PV electricity is not used to charge battery 40, but is instead used to sell electricity back to the power grid 3.

[0069] During the nighttime period after time t0, which corresponds to the end of solar power generation, power can be supplied corresponding to the required battery remaining value W0 using energy pre-charged during the grid charging period, including the late-night period. As a result, if there are no errors in the plan, the energy stored in battery 40 can be efficiently used up (Wa=0) by midnight the following day.

[0070] The differential charging method shown in Figure 6(b) is selected when the required battery charge value W0 is higher than the predicted remaining charge value W1 (W0 > W1), there is no surplus power sales capacity during the daytime on the following day, and the JEPX unit price is low during grid charging hours.

[0071] In differential charging, during grid charging hours, the battery 40 is charged by purchased electricity up to the limit of (W0-W1), which is the difference between the predicted remaining battery capacity W1 and the required remaining battery capacity W0. Furthermore, surplus PV electricity during the daytime is not sold back to the power grid 3, but is used to charge the battery 40. This ensures that the required remaining battery capacity W0 of the battery 40 is secured at time t0, which corresponds to the end of solar power generation.

[0072] During nighttime hours, the energy stored in the battery 40 up to that point can be used to supply power equivalent to the required battery charge value W0. As a result, if there are no errors in the plan, the stored energy in the battery 40 can be efficiently used up and depleted (Wa=0) by midnight the following day.

[0073] In contrast, when the JEPX unit price is not low during grid charging hours, the green mode shown in Figure 6(c) or the PV surplus charging mode shown in Figure 6(d) is selected. The green mode and the PV surplus charging mode share the same charging timing, but differ in the amount of power used for charging and discharging, so they are shown in the same diagram.

[0074] In Green Mode and PV Surplus Charging Mode, because the JEPX unit price is not low, charging of the battery 40 using electricity purchased from power grid 3 is not performed during grid charging hours.

[0075] The green mode in Figure 6(c) is applied when W0 > W1, i.e., when the required battery charge value W0 cannot be secured even if the battery 40 is charged with the surplus PV power Wb for the following day.

[0076] In green mode, basically, during the daytime, surplus PV power is not sold back to the grid but is used to charge the battery 40. However, at time t0, which corresponds to the end of solar power generation, the remaining battery capacity (equivalent to the predicted remaining capacity value W1) is insufficient compared to the required remaining battery capacity value W0.

[0077] Therefore, at night, in addition to the energy charged to the battery 40 by time t0, the deficit (W0-W1) is secured by purchasing electricity from the power grid 3. Even in green mode, if there is no error in the plan, the energy stored in the battery 40 can be completely used up (Wa=0) by midnight the following day.

[0078] The PV surplus charging shown in Figure 6(d) is applied when W1 > W0, i.e., when the required battery capacity W0 can be secured at time t0, which corresponds to the end of solar power generation, by charging with the surplus PV power Wb from the following day.

[0079] In PV surplus charging, during the daytime, the surplus PV energy Wb is used to charge the battery 40. Basically, even in PV surplus charging, similar to green mode, during the daytime, the surplus PV energy is not sold back to the grid but is used to charge the battery 40. However, if the surplus PV energy Wb includes a surplus relative to the battery capacity, etc., that surplus can be applied to selling electricity to the power grid 3.

[0080] At night, the energy charged to the battery 40 by time t0 can supply power corresponding to the required battery remaining value W0. With PV surplus charging, the amount of power generated during the day exceeds the required battery remaining value W0, so even if there is no error in the plan, a certain amount of stored energy will remain in the battery 40 at 0:00 the following day.

[0081] As shown in Figures 3 to 6, by scheduling a lower JPEX unit price corresponding to the electricity purchased by customer 5, the power grid 3 (electricity retailer) can expect improved economic efficiency due to a decrease in electricity procurement prices. Using the resulting cost benefits as a resource, it becomes possible to provide economic benefits to customer 5 who applies the energy management according to this embodiment, such as awarding points or preferential treatment in electricity contract unit prices.

[0082] <How to create an operating schedule for energy storage devices> Next, we will explain an example of a control method for creating an operating schedule for energy storage devices (EcoCute 30 and battery 40) to realize energy management control using Figures 3 to 6.

[0083] Figure 7 shows a flowchart illustrating the process of creating an operating schedule according to the energy management of this embodiment. In this embodiment, the creation process (control method) in Figure 7 can be realized by the processors constituting the server 10 executing a pre-stored program. As mentioned above, the creation process (control method) in Figure 7 can also be realized by multiple processors distributed together, including devices other than the server 10, executing a pre-stored program.

[0084] When a predetermined time (for example, 10pm) arrives after the JEPX unit price for the following 24 hours has been determined, server 10 starts the creation process shown in Figure 7 to create the operation schedule for the following 24 hours (48 slots).

[0085] In step 100 (hereinafter simply referred to as "S"), the server 10 executes the processing for EQ daytime shift control as described in Figure 3. Furthermore, in step S200, the server 10 executes the discharge planning process for the battery 40 in order to realize the discharge shift control as described in Figure 4.

[0086] In S300, Server 10 executes a charging plan process for the battery 40 to implement the selection control of the charging pattern as described in Figure 6. Furthermore, in S600, Server 10 executes a morning control process to modify the discharge plan during grid charging hours (for example, from 0:00 to 8:00). This morning control checks whether there is any room to provide an opportunity to discharge the battery 40 during grid charging hours after the charging plan (S300) has been finalized, in order to effectively utilize the remaining charge of the battery 40. Furthermore, in S700, Server 10 finalizes the operation schedule using the processing results from S100 to S600. This completes the creation of the operation schedule.

[0087] Figure 8 is a diagram illustrating an example of the configuration data for the operation schedule created by the process shown in Figure 7.

[0088] As shown in Figure 8, the day following the schedule creation process (24 hours) is divided into 48 30-minute segments (#1 to #48). For each segment, the JEPX unit price Pjpx [¥ / kWh], the predicted PV power generation amount WPVpr [kWh] from solar cell 50, and the predicted electricity consumption amount WUSpr [kWh] from consumer 5 are obtained.

[0089] The JEPX unit price for each timeframe can be obtained, for example, from information from server 9Y (Figure 1). Similarly, the predicted PV power generation amount WPVpr for each timeframe can be obtained from information from server 9X based on weather forecasts.

[0090] The predicted power consumption WUSpr for each time frame is represented by the sum of the predicted power consumption WUSpr(25) due to the electrical load 25 and the predicted power consumption WUSpr(30) due to the EcoCute 30. The predicted power consumption WUSpr(25) can be obtained by learning from past actual power consumption values ​​for each time frame. This learning process may be performed on server 10, or server 10 may receive learning results from other servers.

[0091] Furthermore, as a result of the EQ daytime shift control in S100, the EQ flag is set to "1" in the frames where the EcoCute 30 is scheduled to perform EQ water heating, and to "0" in all other frames. Therefore, in the case of Figure 3(a), the EQ flag is set to "1" in the frames within the default water heating candidate period (for example, 0:00 to 6:00). In contrast, in the case of Figure 3(b), the EQ flag is set to "0" in the frames within the water heating candidate period, while the EQ flag is set to "1" in the daytime frames.

[0092] The predicted power consumption WUSpr(30) is set according to the power consumption of the EcoCute 30 in frames where the EQ flag is "1", while it is basically set to 0 in frames where the EQ flag is "0". The power consumption of the EcoCute 30 can be determined according to the information from the EcoCute 30 itself.

[0093] As a result, it is understood that the predicted power consumption WUSpr reflects the operating plan of the EcoCute 30 (EQ water heating time period) determined by the EQ daytime shift control (S100).

[0094] In each step, the predicted PV surplus power WSRpv can be calculated by subtracting the predicted power consumption WUSpr from the predicted PV power generation WPVpr. If the subtraction value is negative, WSRpv is set to 0. In other words, the minimum value of the predicted PV surplus power WSRpv is 0.

[0095] Furthermore, the operation plan for the battery storage 40 is determined based on the JEPX unit price Pjpx for each unit, the predicted PV power generation amount WPVpr, the predicted power consumption amount WUSpr, and the predicted PV surplus power amount WSRpv. As a result, each unit is stratified into one of the following: a "grid charging unit" in which the battery storage 40 is charged by electricity purchased from the power grid 3, a "discharge unit" in which the battery storage 40 is discharged, a "PV charging unit" (not shown) in which the battery storage 40 is charged by PV surplus power, or a "remaining charge unit" in which the charging and discharging of the battery storage 40 is stopped.

[0096] In a "discharge frame," the discharge frame flag is set to "1," and the discharge power WDBAT [kWh] of the battery 40 in that frame is set. In frames that are not included in the discharge target, the discharge frame flag is set to "0," and the discharge power WDBAT is set to 0.

[0097] In a "grid charging frame," the grid charging frame flag is set to "1," and the charging energy WCBAT [kWh] for the battery 40 in that frame is also set. In frames that are not included in the charging target, the charging frame flag is set to "0," and the charging energy WCBAT is set to 0.

[0098] In the aforementioned "remaining charge maintenance frame," both the discharge frame flag and the grid charging frame flag are set to their default value of "0." In frames where the battery 40 is neither charged nor discharged, WDBAT=WCBAT=0[kWh] is set.

[0099] Next, we will explain in detail the processing steps in Figure 7. Figure 9 is a flowchart illustrating the detailed processing of the EQ daytime shift control (S100).

[0100] Referring to Figure 9, in S110, the server 10 calculates the average unit price Pjpx(av1), which is the average value of the JEPX unit price (Pjpx) for each 30-minute period during the nighttime operating hours of the EcoCute 30 (for example, from 0:00 to 6:00). In S120, the average unit price Pjpx(av1) calculated in S110 is compared with a predetermined judgment threshold Pt1.

[0101] Shifting the EQ water heating operation to daytime will reduce the amount of electricity sold back to the grid by the amount of electricity used for EQ water heating, while simultaneously reducing the amount of electricity purchased during the nighttime operating hours, which correspond to the default operating time slots for the EcoCute 30, to zero. Therefore, in principle, if the JEPX unit price (average) during nighttime operating hours is higher than the unit price for selling surplus PV electricity (FIT unit price), shifting to daytime operation can improve economic efficiency.

[0102] The determination threshold Pt1 can be set to a value lower than the electricity sales price (FIT price), taking into account the reduction due to transmission charges and renewable energy surcharges, the consumption tax rate, and the transmission efficiency to power grid 3, based on the electricity sales price.

[0103] Server 10 executes the processes S130-S160 to perform a daytime shift when the average unit price Pjpx(av1) during the nighttime operating hours is higher than the determination threshold Pt1 (resulting in a YES judgment in S120). On the other hand, when the average unit price Pjpx(av1) is less than or equal to the determination threshold Pt1 (resulting in a NO judgment in S120), the process proceeds to S180, where it is decided not to perform a daytime shift for the EcoCute 30.

[0104] In S130, Server 10 calculates a provisional predicted PV surplus power amount WSRpv♯ for each time slot of the following day by subtracting the predicted power consumption amount WUSpr(25) of electrical load 25 from the predicted PV power generation amount WPVpr. If the subtraction value is negative, WSRpv♯ is set to 0. In other words, the minimum value of the provisional predicted PV surplus power amount WSRpv♯ is also 0.

[0105] Furthermore, the server 10 obtains the daytime shift prediction amount WEQpr [kWh] from the EcoCute 30 via S140, which corresponds to the predicted total power consumption of the EcoCute 30 during daytime shift execution. The daytime shift prediction amount WEQpr corresponds to the product of the predicted time required for the EQ water heating operation (h) and the amount of power consumed by the EcoCute 30 per hour for water heating.

[0106] Server 10, in S150, allocates the daytime shift prediction amount WEQpr obtained in S140 into 30-minute time slots, and in S160, compares it with the predicted PV surplus power amount WSRpv# for each time slot obtained in S130 to determine whether a daytime shift is necessary.

[0107] Figure 10 is a conceptual diagram illustrating the process for determining whether a daytime shift is necessary in S160 (Figure 9). Figure 10(a) shows an example of a case where a daytime shift is possible, while Figure 10(b) shows an example of a case where a daytime shift is not possible.

[0108] In the example in Figure 10, the predicted time required for EQ water heating is longer than 4 time slots (2 hours) and shorter than 5 time slots (2.5 hours). Therefore, the daytime shift prediction WEQpr is allocated to a total of 5 time slots, as shown by the dotted line, and EQ water heating will be completed midway through the last time slot. The area of ​​each bar in time slots 1 to 4 corresponds to the amount of electricity (kWh) used per hour by the EcoCute 30 for water heating.

[0109] Figure 10 shows a solid line representing a provisional predicted PV surplus power PVsrp# (kW), which is obtained by subtracting the power consumption (kW) of the electrical load 25 from the predicted PV power from the solar cell 50. The sum of this predicted PV surplus power PVsrp# (kW) for each time slot (30 minutes) corresponds to the predicted PV surplus power WSRpv# for each time slot obtained in S130.

[0110] In S160, it is determined whether or not there are any timeframes in which the amount of power used by the EcoCute 30 after allocation exceeds the predicted PV surplus power amount WSRpv#. As shown in Figure 16(a), if there are no timeframes in which the amount of power used by the EcoCute 30 exceeds the predicted PV surplus power amount WSRpv#, S160 is determined to be YES, and it is determined that the daytime shift can be executed.

[0111] Furthermore, if S160 results in a NO judgment, meaning that at least one time frame occurs in which the amount of electricity used by EcoCute 30 exceeds the predicted PV surplus electricity amount WSRpv#, the time period can be shifted to correct the allocation of the amount of electricity used by EcoCute 30 (daytime shift predicted amount WEQpr), and then the judgment of S160 can be tried again.

[0112] Specifically, when S160 determines NO, S162 determines whether there is room to shift the time period. If there are allocation patterns for the daytime shift prediction amount WEQpr that have not yet been tried, S162 determines YES. In this case, S164 shifts the time period, and S150 recalculates the amount of electricity used by the EcoCute 30 (daytime shift prediction amount WEQpr). S160 then determines the amount of electricity used by the EcoCute 30 after the recalculated allocation. When S160 determines YES, it is determined that a daytime shift is possible based on the allocation after the time period shift (S164). The same process can be repeated until S160 determines YES.

[0113] On the other hand, if, even after trying all possible time-shift patterns and performing processes S150 and S160, no allocation of the daytime shift prediction amount WEQpr that results in a YES judgment in S160 can be found, then S162 will be judged as NO.

[0114] In the example shown in Figure 10(b), no matter how the allocation of power consumption for the EcoCute 30 is shifted, there will be frames where the power consumption of the EcoCute 30 exceeds the predicted PV surplus power amount WSRpv#, so both S160 and S162 will be judged as NO.

[0115] Referring again to Figure 9, when the server 10 determines YES in S160, it proceeds to S170 to execute the daytime shift of the EcoCute 30. At the same time, the execution time of the EQ water heating operation is determined according to the allocation of the daytime shift prediction amount WEQpr in S150.

[0116] In response to this, when server 10 determines NO in S160 and S162, it proceeds to S180, and the daytime shift of EcoCute 30 is not executed. In this case, the execution time of the EQ water heating operation is determined to be during the default nighttime operating hours.

[0117] After processing in S170 or S180, server 10 terminates the EQ daytime shift control in S190 and proceeds to the discharge planning process (S200). At this point, the operating schedule for EcoCute 30 is finalized, so in the time frame where the EQ water heating operation is to be performed, the EQ flag is updated from the default value of "0" to "1".

[0118] This also determines the predicted power consumption WUSpr(30) of the EcoCute 30 for each time slot. At this point, the predicted power consumption WUSpr for each time slot, which corresponds to the sum of the predicted power consumption of the electrical load 25 and the EcoCute 30 as explained in Figure 8, can also be determined.

[0119] Figures 11 and 12 are flowcharts illustrating the details of the discharge planning process (S200) shown in Figure 7. The steps S210 to S280 that constitute the discharge planning process S200 are shown separately in Figures 11 and 12.

[0120] As a basic rule for energy management at customer 5, PV power from solar panels 50 is used to cover the electricity consumption of electrical load 25 and EcoCute 30, and any surplus is sold to the power grid 3 or used to charge the battery 40. When the battery 40 needs to be charged, any surplus is preferentially used to charge the battery 40, and any excess relative to the battery 40's maximum charging capacity is sold. On the other hand, if PV power is insufficient to meet the above electricity consumption, the deficit is covered by the discharge power of the battery 40 or by electricity purchased from the power grid 3.

[0121] Referring to Figure 11, Server 10 calculates the expected discharge amount WDP [kWh] for each of the 48 time slots for the following day that are subject to schedule creation via S210. In accordance with the basic rules described above, for time slots where the predicted PV surplus power amount WSRpv > 0, the expected discharge amount WDP = 0 is set. On the other hand, for time slots where the predicted PV surplus power amount WSRpv = 0, the expected discharge amount WDP can be set according to the difference between the predicted power consumption WUSpr and the predicted PV power generation WPVpr, i.e., the subtraction value (WUSpr - WPVpr) (WDP = WUSpr - WPVpr). In S210, all time slots where the expected discharge amount WDP > 0 are determined to be "discharge candidate time slots".

[0122] In S215, server 10 assigns a JEPX unit price (Pjpx) to each frame, and in S220, it determines the "discharge reference frame" based on the JEPX unit price. Specifically, among the discharge candidate frames mentioned above, the frame with the highest JEPX unit price is determined to be the discharge reference frame. Furthermore, in S220, the discharge priority is determined for the discharge candidate frames other than the discharge reference frame.

[0123] Specifically, among the discharge candidate frames, those that appear later in chronological order than the discharge reference frame are designated as "high discharge priority" frames (groups), while those that appear earlier are designated as "low discharge priority" frames (groups). Furthermore, within each of the "high discharge priority" and "low discharge priority" frame groups, the priority is set higher the smaller the time difference (time lag) from the discharge reference frame.

[0124] Server 10 sets the discharge reference frame as a "discharge frame" using S225. Furthermore, it sets the assumed discharge amount WDP of the discharge reference frame to the initial value of the total discharge amount WDttl [kWh] of the discharge frames. Once a frame is confirmed as a discharge frame, the discharge flag of that frame is updated from the default value of "0" to "1".

[0125] In S230, Server 10 adds the estimated discharge amount WDP of the highest-priority discharge frame (or group of frames) among the remaining discharge candidate frames to the total discharge amount WDTtl. Then, in S235, Server 10 compares the total discharge amount WDTtl after the addition in S225 with the rated capacity WBATrt of the battery 40. The rated capacity WBATrt corresponds to the amount of charging energy (kWh) corresponding to SOC = 100 (%).

[0126] Server 10, when the total discharge amount WDTtl is less than or equal to the rated capacity WBATrt (when S235 is judged as YES), confirms the frame in S240, which has the expected discharge amount WDP added in S230, as a "discharge frame". Furthermore, in S250, it is determined whether there are any "unconfirmed frames" remaining among the discharge candidate frames (group) with high discharge priority that were not subject to the addition process in S230. If there is one or more "unconfirmed frames" among the frames (group) with high discharge priority (when S250 is judged as NO), Server 10 returns to S230.

[0127] On the other hand, when the total discharge amount WDTtl is greater than the rated capacity WBATrt (when NO is determined in S235), the server 10, in S245, removes all remaining discharge candidate frames, including the frame that was added in S230 immediately before, from the discharge frames, and proceeds to S275 in Figure 12, thereby ending the discharge frame determination process.

[0128] In contrast, while S250 is determined to be NO, the addition process by S230 and the determination process by S235 are repeatedly executed. As a result, until the total discharge amount WDttl reaches the rated capacity WBATrt, the discharge candidate frames (groups) with high discharge priority are determined to be "discharge frames" in order from those closest to the discharge reference frame on the time axis.

[0129] Even if all of the discharge candidate frames (groups) with high discharge priority are confirmed as discharge frames, if the total discharge amount WDttl does not reach the rated capacity WBATrt, S250 is judged as YES, and the process proceeds to S255 in Figure 12.

[0130] Referring to Figure 12, in S255, server 10 compares the JEPX unit price Pjpx of one target frame selected according to priority (distance on the time axis from the discharge reference frame) from the group of frames with "low discharge priority" determined in S220 with the average unit price Pjpx(av2), which is the average of the JEPX unit prices of the group of frames with "low discharge priority".

[0131] When the JEPX unit price Pjpx of the target frame is higher than the average unit price Pjpx(av2) (when S255 is judged as YES), the server 10 checks in S257 whether the expected discharge amount WDP of the target frame is less than or equal to the remaining discharge capacity (WBATrt-WDttl) which is the total discharge amount WDttl up to the present time relative to the rated capacity WBATrt.

[0132] Then, when the expected discharge amount of the frame under evaluation is less than or equal to the discharge capacity (WDP ≤ WBATrt - WDttl) (when S257 is judged as YES), S260 confirms that the frame under evaluation in S255 is a "discharged frame". In addition, the discharge power amount WDBAT of the frame is set according to the expected discharge amount WDP (WDBAT = WDP).

[0133] Furthermore, in S260, the total discharge amount WDttl is updated to include the newly determined estimated discharge amount WDP of the discharge frame.

[0134] On the other hand, when S257 determines NO (WDP > WBATrt - WDttl), that is, when the expected discharge amount of the frame being judged is greater than the discharge capacity, S265 excludes the frame being judged in S255 from being a "discharged frame".

[0135] After S260 or S265, Server 10 determines in S270 whether there are any "undetermined frames" remaining among the discharge candidate frames (groups) with low discharge priority that were not subject to determination in S255. If there is one or more "undetermined frames" among the discharge candidate frames (groups) with low discharge priority (resulting in a NO determination in S270), processing returns to S255. Then, the next frame to be determined is selected, and processing from S255 to S270 is executed.

[0136] The process from S255 to S270 is repeated until the number of "unconfirmed frames" becomes 0 and S270 is judged as YES. As a result, the process from S255 to S265 is executed for all discharge candidate frames (groups) with low discharge priority. Within the range where the total discharge amount WDttl is less than or equal to the rated capacity WBATrt, frames (groups) with low discharge priority whose JEPX unit price Pjpx is higher than the average unit price Pjpx(av2) can be added to the "discharge frames" and confirmed.

[0137] When server 10 determines NO in S235, or YES in S270, that is, when it has determined whether all discharge candidate frames are confirmed as discharge frames, or when the total discharge amount WDttl from confirmed discharge frames reaches the rated capacity WBATrt of battery 40, it proceeds to S275. When S275 is executed, the "discharge frames" and the discharge amount WDBAT in each discharge frame in the battery 40's operating schedule for the next day have been determined. Therefore, in S275, server 10 determines the total discharge amount WDttlf [kWh] for all discharge frames on the next day according to the total discharge amount WDttl at that time.

[0138] After processing S275, server 10 terminates the discharge planning process in S280 and proceeds to the charge planning process (S300).

[0139] Figure 13 is a flowchart illustrating the details of the charging planning process (S300) shown in Figure 7.

[0140] Referring to Figure 13, Server 10, via S310, sets the required battery charge value W0 as described in Figure 5, according to the total discharge amount WDttlf for the entire discharge frame calculated in the discharge plan. Basically, it is possible to set W0 = WDttlf, but the required battery charge value W0 may be set considering losses during charging and discharging, etc.

[0141] Server 10, in S320, calculates the battery charge value Wa at 0:00 the following day based on the battery charge value at that time, and adds this to the predicted PV surplus power Wb during the daytime the following day based on the predicted PV surplus power WSRpv for all frames of the following day to calculate the predicted charge value W1 as explained in Figure 5. As described above, the predicted charge value W1 is the predicted value of the remaining charge of battery 40 at the end of solar power generation the following day (corresponding to time t0 in Figure 4).

[0142] Server 10 compares the required battery charge value W0 (S310) with the predicted battery charge value W1 of battery 40 using S330.

[0143] When the predicted remaining charge value W1 of the battery 40 is less than the required remaining charge value W0 (when S330 determines YES), the server 10 determines that this corresponds to the case where W0 > W1 in Figures 5 and 6, and proceeds to S340 to execute the differential charging control process shown in Figure 6(b) (S400: Figures 14 and 15).

[0144] In response, when the predicted remaining charge value W1 of the battery 40 is greater than or equal to the required remaining charge value W0 (when NO is determined in S330), the server 10 determines that this corresponds to the case where W1 > W0 in Figure 5, and proceeds to S350 to execute the processing for FIT charging control shown in Figure 6(a) (S500: Figures 16 and 17).

[0145] As described above, the control process in Figure 13 allows for the selection of either the differential charging control process (S400) or the FIT charging control process (S500) based on a comparison and determination of the required remaining battery charge value W0 and the predicted remaining charge value W1 of the battery 40, as explained in Figures 5 and 6, and a charging plan is formulated.

[0146] Furthermore, in order to suppress errors in the predicted remaining charge value W1 of the battery 40 and improve the accuracy of the above comparison judgment, it is preferable to execute the charging plan process (S300) just before midnight the next day, within the limits of the calculation processing time. Therefore, it is not necessary to execute S100 to S700 consecutively for the control process shown in Figure 7. After executing S100, or after executing S100 and S200, a waiting time may be provided, and the process from S300 onwards may be executed as far as possible, waiting until just before midnight the next day.

[0147] Figures 14 and 15 are flowcharts illustrating the details of the differential charging control process (S400) performed in the case of W0 > W1 in Figures 5 and 6. The steps S410 to S480 that constitute the differential charging control process S400 are shown separately in Figures 14 and 15.

[0148] Referring to Figure 14, the server 10 calculates the required grid charge amount WCHgrd [kWh] from the predicted remaining charge value W1 and the required remaining charge value W0 of the battery 40 using S410. Since the grid charge amount WCHgrd corresponds to the difference between the required remaining charge value W0 and the predicted remaining charge value W1, the grid charge amount WCHgrd can basically be calculated by subtracting the predicted remaining charge value W1 from the required remaining charge value W0 (WCHgrd = W0 - W1).

[0149] In differential charging control, whether or not to charge the battery 40 with electricity purchased from the power grid 3 during a predetermined grid charging time (for example, from 0:00 to 8:00) is determined based on a comparison between the JEPX unit price for the discharge time determined in the discharge plan and the JEPX unit price during the grid charging time.

[0150] Therefore, server 10 calculates the determination threshold Pt2 for the grid charging unit price based on the JEPX unit price at the discharge time using S415. The determination threshold Pt2 is set lower than the JEPX unit price (weighted average) at the discharge time, taking into account the charge and discharge losses of the battery 40, the losses in the power grid 3, and the cost increases due to transmission charges, renewable energy surcharges, and consumption tax rates.

[0151] Server 10, via S420, sequentially selects one of the 8-hour timeframes #1 to #16 included in the grid charging time period (0:00 to 8:00) as the target for evaluation, and then, via S425, checks the predicted PV surplus power amount WSRpv for the target timeframe.

[0152] In frames where the predicted PV surplus power WSRpv > 0, S425 is judged as NO, and in order to avoid charging by purchasing power from power grid 3, S440 removes the frame in question from the "grid charging frame".

[0153] In frames where the predicted PV surplus power amount WSRpv = 0 (when S425 is judged as YES), S430 compares the JPEX unit price of that frame (the frame to be judged) with the judgment threshold Pt2 set in S415.

[0154] When S430 determines YES, that is, when no predicted PV surplus power WSRpv occurs in the target time slot and the JPEX unit price is lower than the determination threshold Pt2, S435 provisionally determines that the target time slot is a "grid charging time slot".

[0155] After processing the frame to be judged in S420 in S435 or S440, Server 10 determines in S445 whether all frames #1 to #16 included in the grid charging time zone have been selected as frames to be judged. If there are any frames that have not been judged (when S445 is determined to be NO), the process returns to S420, the next frame to be judged is selected, and processing in S425 to S440 is executed. As a result, when S445 is determined to be YES, the determination of whether or not to tentatively confirm all frames included in the grid charging time zone as "grid charging frames" has been completed through processing in S425 to S440. When S445 is determined to be YES, Server 10 proceeds to processing in S450 in Figure 15.

[0156] Referring to Figure 15, Server 10 checks in S450 whether there are any frames that have been provisionally determined as "system charging frames" by the processing in Figure 14. If there are 0 frames that have been provisionally determined as "system charging frames", S450 is judged as NO, and the process proceeds to S475. In S475, Server 10 finalizes the charging plan in such a way that no system charging frames are set during the system charging time period (0:00 to 8:00).

[0157] As a result, if the JPEX unit price during grid charging hours is not low and economic efficiency does not improve by charging the battery 40 with purchased electricity, grid charging of the battery 40 is avoided, and the charging plan is finalized in a manner in which the green mode shown in Figure 6(c) is selected.

[0158] In response, if there is one or more frames that have been provisionally confirmed as "grid charging frames" (when S450 determines YES), server 10 confirms the frame with the lowest JPEX unit price among the provisionally confirmed "grid charging frames" as the "grid charging frame" in S455. Once a frame is confirmed as a grid charging frame, the grid charging flag for that frame is updated from the default value of "0" to "1". In addition, the charging energy WCBAT for that frame is set according to the minimum value between the remaining grid charging amount WCHgrd#[kWh] at that time and the rated charging energy amount (kWh) of the battery 40 for one frame (30 minutes).

[0159] Following S455, Server 10 updates the remaining grid charge amount WCHgrd♯ in S460, reflecting the charging energy WCBAT of the grid charging time confirmed in S455. The remaining grid charge amount WCHgrd♯ is initially set to the required grid charge amount WCHgrd calculated in S410, and is updated each time a new grid charging time is confirmed (S455) by successively subtracting the charging energy WCBAT of the confirmed grid charging time.

[0160] After the server 10 updates the remaining amount WCHgrd♯ of the grid charge amount by S460, it determines whether WCHgrd♯ remains by S462. When WCHgrd♯ > 0 (when the determination in S462 is YES), the server 10 determines whether there are any provisionally confirmed commands for which S455 has not been processed by S465. If there are remaining unprocessed provisionally confirmed commands (when the determination in S465 is NO), the process returns to S445, and among the remaining commands of the remaining provisionally confirmed "grid charge commands", the command with the lowest JPEX unit price is determined as the "grid charge command", and the processes of S460 to S465 are executed.

[0161] As a result, within the range where the total charge amount WCBAT of the "grid charge commands" does not exceed the required grid charge amount WCHgrd (S410), the commands with lower JEPX unit prices among the provisionally confirmed grid charge commands can be determined as the "grid charge commands" in order.

[0162] When the determination in S465 is YES, or when the determination in S462 is NO, that is, when the required grid charge amount WCHgrd (S410) can be ensured by determining sufficient grid charge commands, or when the process of S455 has been executed for all provisionally confirmed grid charge commands, the process proceeds to S470 to determine the charging plan, and then transfers to the morning control process (S600) by S480.

[0163] Figures 16 and 17 are flowcharts for explaining the details of the FIT charge control process (S500) executed in the case of W0 < W1 in Figures 5 and 6. S510 to S580 constituting the FIT charge control process S500 are described separately in Figures 16 and 17.

[0164] Referring to Figure 16, the server 10 calculates the required grid charge amount WCHgrd according to the required battery remaining amount value W0 by S510. Basically, the grid charge amount WCHgrd can be set to be equal to the required battery remaining amount value W0 (WCHgrd = W0).

[0165] In FIT charging control, whether or not to charge the battery 40 with electricity purchased from the power grid 3 during a predetermined grid charging time (for example, from 0:00 to 8:00) is determined based on a comparison between the JEPX unit price for the discharge time determined in the discharge plan and the electricity sales price under FIT.

[0166] Therefore, the server 10 calculates the determination threshold Pt3 for the grid charging unit price based on the contracted electricity sales unit price under FIT using S515. The determination threshold Pt3 can be set lower than the electricity sales unit price, taking into account the charging and discharging losses of the battery 40 and the losses in the power grid 3, as well as the cost increase due to the transmission and distribution unit price, the renewable energy surcharge unit price, and the consumption tax rate.

[0167] Server 10, via S520, sequentially selects one of the 8-hour timeframes #1 to #16 included in the grid charging time period (0:00 to 8:00) as the target for evaluation, and then, via S525, checks the predicted PV surplus power amount WSRpv for the target timeframe.

[0168] In frames where the predicted PV surplus power WSRpv > 0, S525 is judged as NO, and in order to avoid charging by purchasing power from power grid 3, S540 removes the frame in question from the "grid charging frame".

[0169] In frames where the predicted PV surplus power amount WSRpv=0 (when S525 determines YES), S530 compares the JPEX unit price for that frame (the frame being judged) with the judgment threshold Pt3 set in S515.

[0170] When S530 determines YES, that is, when no predicted PV surplus power WSRpv occurs in the target time frame and the JPEX unit price is lower than the determination threshold Pt3, S530 provisionally determines that the target time frame is a "grid charging time frame".

[0171] After processing the frame selected in S520 in S535 or S540, Server 10 determines in S545 whether all frames #1 to #16 included in the grid charging time zone have been selected as frames to be judged. If there are any frames that have not been judged (when S545 is determined to be NO), the process returns to S520, the next frame to be judged is selected, and processing in S525 to S540 is executed. As a result, when S545 is determined to be YES, it is determined whether all frames included in the grid charging time zone are provisionally confirmed as "grid charging frames" by processing in S425 to S440. When S545 is determined to be YES, Server 10 proceeds to processing in S550 in Figure 17.

[0172] Referring to Figure 17, Server 10 checks in S550 whether there are any frames that have been provisionally determined as "system charging frames" by the processing in Figure 16. If there are 0 frames that have been provisionally determined as "system charging frames", S550 is determined to be NO, and the process proceeds to S575. In S575, Server 10 finalizes the charging plan in such a way that no system charging frames are set during the system charging time period (0:00 to 8:00).

[0173] As a result, if the JPEX unit price during grid charging hours is not low, and charging the battery 40 with surplus PV power is more economical than charging the battery 40 with purchased electricity, the charging plan is finalized in such a manner that grid charging of the battery 40 is avoided and surplus PV charging as shown in Figure 6(d) is selected.

[0174] In response, if there is one or more frames that have been provisionally confirmed as "grid charging frames" (when S550 determines YES), server 10 confirms the frame with the lowest JPEX unit price among the provisionally confirmed "grid charging frames" as the "grid charging frame" in S555. Once a frame is confirmed as a grid charging frame, the grid charging flag for that frame is updated from the default value of "0" to "1". In addition, the charging energy WCBAT for that frame is set according to the minimum value between the remaining grid charging amount WCHgrd# at that time and the rated charging energy (kWh) of the battery 40 for one frame (30 minutes).

[0175] Following S555, Server 10 updates the remaining grid charge amount WCHgrd♯ in S560, reflecting the charging energy WCBAT of the grid charging time slot confirmed in S555. The remaining grid charge amount WCHgrd♯ is initially set to the required grid charge amount WCHgrd calculated in S510, and is updated each time a new grid charging time slot is confirmed (S555) by successively subtracting the charging energy WCBAT of the confirmed grid charging time slot.

[0176] After updating the remaining grid charge amount WCHgrd♯ by S560, Server 10 determines in S562 whether WCHgrd♯ remains. If WCHgrd♯ > 0 (YES determination in S562), Server 10 determines in S565 whether there are any unprocessed provisional confirmation frames remaining in S555. If there are any unprocessed provisional confirmation frames remaining (NO5 determination in S565), the process returns to S445, and the frame with the lowest JPEX unit price among the remaining provisional confirmation frames is confirmed as the "grid charge frame," and the processing of S560 to S565 is executed.

[0177] As a result, within the range where the total amount of charging energy WCBAT for each "grid charging slot" does not exceed the required grid charging amount WCHgrd(S510), the provisionally determined grid charging slots can be confirmed as "grid charging slots" in order from those with the lowest JEPX unit price.

[0178] When server 10 determines NO in S562, or YES in S565, that is, when it has determined that enough grid charging frames are available to secure the required grid charging amount WCHgrd (S510), or when processing S555 has been performed on all of the tentatively determined grid charging frames, it proceeds to S570 to finalize the charging plan, and then proceeds to morning control processing (S600) in S580.

[0179] Figure 18 is a flowchart illustrating the details of the morning control process shown in Figure 7. As described above, the morning control process attempts to efficiently use the previous day's battery charge value to add an additional discharge period during the grid charging time before PV surplus occurs (for example, from 0:00 to 8:00).

[0180] Referring to Figure 18, Server 10 sets the morning discharge amount WCMR [kWh], which corresponds to the total amount of electricity that can be discharged from the battery 40 during the grid charging period (0:00 to 8:00), via S610. The morning discharge amount WCMR can be calculated based on the required battery charge value W0, the battery charge value Wa from the previous day, and the predicted PV surplus electricity amount Wb for the next day, similar to S310 and S320 in Figure 13 (charging plan).

[0181] If the predicted PV surplus power amount Wb for the next day is greater than the required battery remaining value W0, the battery 40 can be sufficiently charged by the PV surplus power during the day, and therefore, the morning discharge amount WCMR can be set to be the same as the previous day's battery remaining value Wa using S610.

[0182] On the other hand, if the required battery charge value W0 is greater than the predicted PV surplus power amount Wb for the next day, the battery 40 cannot be sufficiently charged by the PV surplus power during the day, so it is necessary to leave the battery charge value Wa from the previous day. Therefore, using S610, the morning discharge amount WCMR can be set by subtracting (W0-Wb), which corresponds to the daytime charging shortfall, from the previous day's battery charge value Wa.

[0183] In S620, Server 10 checks for the presence of "system charging time slots" during the system charging time period, based on the results of the charging plan processing (S300 (S400, S500)). If no system charging time slots are provided (resulting in a YES determination in S620), additional discharge time slots (also called "morning discharge time slots") are provided in order from the time slots with the highest JEPX unit prices, through processing in S630 to S645.

[0184] In S630, Server 10 selects the time slot with the highest JEPX unit price from the remaining time slots excluding the confirmed "discharge time slots" within the grid charging time period and provisionally designates it as the "discharge time slot (morning discharge time slot)". Furthermore, the predicted discharge amount for that morning discharge time slot is set according to the assumed discharge amount WDP for that time slot.

[0185] Server 10, in S640, compares the total discharge amount of the confirmed and provisionally confirmed morning discharge frames with the morning discharge amount WCMR set in S610. If the total discharge amount of the morning discharge frames is less than the morning discharge amount (NO determination in S640), S645 confirms the frame selected in S630 as the "morning discharge frame" and returns processing to S630. This allows the processing of S630 to S645 to be performed on the remaining frames, excluding the entire set of "discharge frames" including the confirmed "morning discharge frame".

[0186] Steps S630 to S645 are repeatedly executed until S640 is determined to be YES. Within the range where the total predicted discharge amount does not exceed the morning discharge amount, the "morning discharge frames" can be determined in order from the frames with the lowest JEPX unit price.

[0187] If a grid charging frame is available (when NO is determined in S620), the server 10 processes S650 to S665 to provide additional discharge frames (also called "morning discharge frames") in order from the frame with the earliest timeline.

[0188] In S650, Server 10 selects the earliest time slot in chronological order from the remaining time slots, excluding the confirmed "discharge time slots" and "system charging time slots" within the grid charging time period, and provisionally designates it as the "discharge time slot (morning discharge time slot)". Furthermore, the predicted discharge amount for that morning discharge time slot is set according to the assumed discharge amount WDP for that time slot.

[0189] Server 10, in S660, compares the total discharge amount of the confirmed and provisionally confirmed morning discharge frames with the morning discharge amount set in S610. If the total discharge amount of the morning discharge frames is less than the morning discharge amount (NO determination in S660), S665 confirms the frame selected in S650 as the "morning discharge frame" and returns processing to S650. This allows the processing of S650 to S665 to be performed on the remaining frames, excluding the entire set of "discharge frames" and "system charging frames" including the confirmed "morning discharge frame".

[0190] Steps S650 to S665 are repeatedly executed until S660 is determined to be YES. This allows the "morning discharge frames" to be determined in order from the earliest frames in the time series, within the range where the total predicted discharge amount does not exceed the morning discharge amount.

[0191] As a result, in order to efficiently utilize the battery charge value from the previous day, it becomes possible to add discharge frames during the grid charging period before surplus PV power is generated (for example, from 0:00 to 8:00), and by efficiently using the remaining capacity of the battery 40 before charging of the battery 40 with surplus PV power begins, economic efficiency can be further improved. <Summary of energy management according to this embodiment> Figure 19 is a diagram illustrating the pattern classification of the results of creating the operation schedule using the processes shown in Figures 7 to 18.

[0192] Referring to Figure 19, the operating schedule patterns are classified by the combination of whether or not there is an EQ daytime shift and the charging patterns of the four batteries shown in Figures 6(a) to (d).

[0193] Whether or not an EQ daytime shift is necessary is determined according to the results of the JEPX unit price comparison judgment (S120) and the daytime shift prediction amount securing determination (S160) in the EQ daytime shift control processing (S100). In the JEPX unit price comparison judgment (S120), as described above, the average value of the JEPX unit price during the nighttime operating period of the EcoCute 30 is compared with the determination threshold Pt1. In the daytime shift prediction amount securing determination (S160), as described above, it is determined whether or not the amount of electricity used when shifting the EQ water heating operation to daytime (daytime shift prediction amount WEQpr) can be secured by the predicted PV surplus electricity amount (WSRpv#) in the shift destination time period.

[0194] As explained in Figure 9, if both the JEPX unit price comparison judgment (S120) and the daytime shift forecast amount securing feasibility judgment (S160) result in "YES", the EcoCute 30 will perform the EQ water heating operation during the daytime hours when surplus PV power is secured, rather than during the "default water heating candidate period" time (for example, 0:00 to 6:00).

[0195] On the other hand, if the result of at least one of the JEPX unit price comparison judgment (S120) and the daytime shift forecast quantity securing determination (S160) is "NO", the daytime shift will not be executed. In this case, the EcoCute 30 will perform EQ water heating operation during the "default water heating candidate period (for example, 0:00 to 6:00)".

[0196] The discharge planning process (S200) is performed in common for all four battery charging patterns, regardless of whether or not there is an EQ daytime shift. As a result, the creation of a discharge plan that takes the JEPX unit price into consideration, as explained in Figure 11, specifically the selection of discharge frames that include the frame with the highest JEPX unit price (discharge reference frame), is applied in a common manner to all patterns.

[0197] As explained in Figure 13, in the charging plan (S300), a comparison and determination (S330) is made between the required remaining battery charge value W0 for corresponding to the discharge plan and the predicted remaining charge value W1 of the battery 40 at the end of solar power generation. Based on this, either the differential charging control process (S400) or the FIT charging control process (S500) is selectively executed.

[0198] If the predicted remaining charge value W1 is greater than the required battery remaining charge value W0 (W1 > W0), the FIT charging process shown in Figures 16 and 17 is executed, and a comparison process is performed between the JEPX unit price for each time slot in the grid charging time period (0:00 to 8:00) corresponding to the "default charging candidate period" and the judgment threshold Pt3 (S530). Depending on the result of the comparison process in S530, either FIT charging as shown in Figure 6(a) or PV surplus charging as shown in Figure 6(d) is applied to the charging of the battery 40.

[0199] Specifically, if the comparison process in S530 reveals that there is one or more frames where the JEPX unit price is less than or equal to the judgment threshold Pt3, then the battery 40 is grid-charged using at least a portion of those frames, and as a result, the FIT charging shown in Figure 6(a) is applied.

[0200] In contrast, if the comparison process in S530 shows that there are no frames where the JEPX unit price is below the judgment threshold Pt3, then the battery 40 will not be charged by the grid during the grid charging time, and as a result, the PV surplus charging shown in Figure 6(d) will be applied.

[0201] On the other hand, if the required battery charge value W0 is greater than the predicted charge value W1 (W0 > W1), the differential charging process shown in Figures 14 and 15 is executed, and a comparison process is performed between the JEPX unit price for each time slot in the grid charging period (0:00 to 8:00) corresponding to the "default charging candidate period" and the judgment threshold Pt2 (S430). Depending on the result of the comparison process in S430, either differential charging as shown in Figure 6(b) or the green mode as shown in Figure 6(c) is applied to the charging of the battery 40.

[0202] Specifically, if the comparison process in S430 reveals that there is one or more frames where the JEPX unit price is less than or equal to the judgment threshold Pt2, then the battery 40 is grid-charged using at least a portion of those frames, and as a result, the differential charging shown in Figure 6(b) is applied.

[0203] In contrast, if the comparison process in S430 shows that there are no frames where the JEPX unit price is below the judgment threshold Pt2, then the battery 40 will not be charged by the grid during the grid charging time, and as a result, the green mode shown in Figure 6(c) will be applied.

[0204] Furthermore, the morning control process (S600) described in Figure 18 can be applied with common content to all patterns obtained by the processes S100 to S300 (S400, S500). This creates an operating schedule for the energy storage device to which the energy management according to this embodiment is applied. <Representation of the energy management system according to this embodiment using a functional block diagram> Figure 20 is a functional block diagram illustrating the energy management according to this embodiment.

[0205] Referring to Figure 20, in the energy management system according to this embodiment, the server 10 shown in Figure 1 comprises a prediction information collection unit 101, a JEPX unit price collection unit 102, and a creation processing management unit 110.

[0206] The forecast information collection unit 101 acquires, for example, the predicted PV power generation amount (solar cell 50) for each time slot of the next day based on weather forecast information from the server 9X. Furthermore, the forecast information collection unit 101 acquires the predicted power consumption amount (kWh) for each time slot of the next day based on past performance data, either through forecast calculations within the server 10 or from data from other devices.

[0207] The creation processing management unit 110 includes an EQ daytime shift control processing unit 111 for executing the process of S110, a discharge planning processing unit 112 for executing the process of S110, and a charge planning processing unit 115 for executing the process of S300. The charge planning processing unit 115 includes a differential charge processing unit 116 for executing the process of S400 and a FIT charge processing unit 117 for executing the process of S500.

[0208] The creation process management unit 110 further includes a morning control processing unit 118 for executing the S600 process and a schedule creation unit 119 for executing the S700 process. The creation process management unit 110 manages the entire operation schedule creation process by managing the startup timing of the EQ daytime shift control processing unit 111 (S100), discharge planning processing unit 112 (S200), charge planning processing unit 115 (S300), differential charge processing unit 116 (S400), FIT charge processing unit (S500), morning control processing unit 118 (S600), and schedule creation unit (S700), as well as the transfer of data between each processing unit.

[0209] The creation process management unit 110 starts the operation schedule creation process at a predetermined time (for example, 10pm) after the JEPX unit price for the following day has been determined, every day. Furthermore, as described above, in order to improve the accuracy of the predicted remaining charge value W1 of the battery 40, it is preferable to execute the processes from the charge planning process (S300) onward as late as possible, before midnight the following day. Therefore, the creation process management unit 110 may proceed with the operation schedule creation process in a manner that includes a waiting interval (for example, between S200 and S300) rather than executing the control processes shown in Figure 7 in a series of steps.

[0210] The schedule creation unit 119 integrates the processing results from the EQ daytime shift control processing unit 111 (S100), the discharge planning processing unit 112 (S200), the charge planning processing unit 115 (S300), the differential charge processing unit 116 (S400) or the FIT charge processing unit (S500), and the morning control processing unit 118 (S600) to create the operating schedule for the energy storage device of customer 5. Typically, the creation of the operating schedule is completed when the data set exemplified in Figure 8 is finalized for each frame.

[0211] The created operation schedule is sent to HEMS20, and HEMS20 sequentially generates operation commands for the energy storage devices (storage battery 40 and EcoCute 30) for the following day according to the operation schedule sent from server 10.

[0212] In this embodiment, as illustrated in Figure 20, all functions are implemented by the processor of server 10. However, as described above, the functions of each functional block in Figure 20 may be distributed across multiple processors, including devices other than server 10.

[0213] As described above, the energy management according to this embodiment can automatically create an economically efficient operating schedule for energy storage devices (storage battery 40 and / or EcoCute 30) by taking into account the electricity procurement unit price (JPEX unit price). In particular, by controlling the charging timing of the storage battery 40, including whether or not grid charging is performed using purchased electricity, while taking into account the JEPX unit price during the default grid charging period, economic efficiency can be improved.

[0214] In this embodiment, we have described a case where both a battery 40 and an EcoCute 30 are installed as energy storage devices at customer 5. However, even in cases where only an EcoCute 30 is installed and no battery 40 is installed as an energy storage device, the operating schedule for the EcoCute 30 (determining the time slots in which the EQ water heating operation is performed) can be created according to the energy management of this embodiment by executing only the EQ daytime shift control processing (S100).

[0215] Similarly, even in the case where customer 5 does not have an EcoCute 30 as an energy storage device, and only a battery 40 is installed, the operation schedule of the battery 40 (determination of charging (grid charging) / discharging / stopping at each time slot) can be created in accordance with the energy management according to this embodiment by executing at least the discharge planning process (S200) and the charge planning process (S300).

[0216] In other words, in cases where both a battery 40 and an EcoCute 30 are installed as energy storage devices, the accuracy of the operating schedule can be improved by performing discharge planning processing that reflects the power required for the EQ water heating operation by the EcoCute 30. Specifically, the above effect can be obtained by preventing calculation errors in the required battery charge value W0 and predicted charge value W1 of the battery 40 used in the comparison processing of S330 of the charging plan, which are affected by whether or not there is an EQ daytime shift.

[0217] Furthermore, by performing the morning control process (S600) in addition to the discharge planning process (S200) and the charge planning process (S300), the remaining capacity of the battery 40 can be efficiently used during the grid charging period until charging with surplus PV power begins, thereby further improving economic efficiency. <Note> The embodiments and variations described above include the following technical concepts. [Example 1] A control method for energy management targeting a consumer (5) that is able to buy and sell electricity to and from a power grid (3) and is equipped with an electrical load (25), a solar power generation device (50), and energy storage devices (30, 40), The power procurement unit price (Pjpx) for the aforementioned power system is obtained for each of the multiple time slots obtained by dividing the 24 hours of the following day, For each of the aforementioned multiple frames, the predicted PV power generation amount (WPVpr) from the solar power generation device based on the weather forecast information for the following day and the predicted power consumption amount (WUSpr) based on past actual values ​​of power consumption at the consumer are obtained. The process involves comparing the electricity procurement unit price in the first group of time slots, which are among the multiple time slots and which include the default operating candidate period of the energy storage device, with a predetermined first judgment threshold (Pt1 to Pt3). A control method comprising creating an operating schedule for the energy storage device for the following day based on the predicted PV power generation amount, the predicted power consumption amount, and the results of the comparison and determination. [Example 2] The aforementioned energy storage device is The system includes a battery (40) that can be charged by the surplus power generated by the solar power generation device (50) relative to the power used by the customer (5), or by purchased power from the power grid (3), and can also supply the customer's power by discharging it. The aforementioned operating schedule includes determining whether the battery operates in a charging, discharging, or stopping mode for each of the plurality of time slots. The aforementioned candidate operating period includes the default candidate charging period for the battery using the purchased electricity, which is set during nighttime hours. The comparison determination involves comparing the power procurement unit price (Pjpx) of each frame in the first frame group with the first determination threshold (Pt2, Pt3). The control method according to Example 1, wherein the operation schedule for the following day is created such that, in the first group of time slots, grid charging of the battery using purchased electricity is not performed in time slots where the electricity procurement unit price is higher than the first determination threshold. [Example 3] The control method described above is The operation plan for the battery is determined such that at least one discharge time slot in which the battery discharges is set among the plurality of time slots, so that the battery (40) discharges preferentially in time slots where the power procurement unit price (Pjpx) is high. The required remaining battery capacity (W0) is calculated by summing the estimated discharge amount (WDP) obtained from the predicted PV power generation amount (WPVsr) and the predicted power consumption amount (WUSpr) in each of the discharge units, The system further comprises calculating the predicted remaining battery charge (W1) at the time of the end of power generation (t0) of the solar power generation system using the predicted PV power generation amount and predicted power consumption amount of the plurality of frames, and the remaining battery charge at the time of creating the operation schedule for the following day. The first determination threshold (Pt2) is set to be lower than the average value of the power procurement unit price in at least one discharge step when the required battery remaining value is greater than the predicted remaining value (W0 > W1). The control method according to Example 2, wherein the operation schedule for the following day is created such that, if the required battery remaining charge is greater than the predicted remaining charge (W0 > W1), grid charging of the battery is performed using at least a portion of the first group of frames in which the power procurement unit price is lower than the first determination threshold, up to the difference between the required battery remaining charge and the predicted remaining charge (W0 - W1). [Example 4] The control method described above is The operation plan for the battery is determined such that at least one discharge time slot in which the battery discharges is set among the plurality of time slots, so that the battery (40) discharges preferentially in time slots where the power procurement unit price (Pjpx) is high. The required remaining battery capacity (W0) is calculated by summing the estimated discharge amount (WDP) obtained from the predicted PV power generation amount (WPVsr) and the predicted power consumption amount (WUSpr) in each of the discharge units, The system further comprises calculating the predicted remaining battery charge (W1) at the time of the end of power generation (t0) of the solar power generation system using the predicted PV power generation amount and predicted power consumption amount of the plurality of frames, and the remaining battery charge at the time of creating the operation schedule for the following day. The first determination threshold (Pt3) is set such that, when the predicted remaining charge value is greater than the required remaining charge value of the storage battery (W1 > W0), it becomes lower than the electricity sales price to the power grid. The control method according to Example 2, wherein the operation schedule for the following day is created such that, if the predicted remaining charge value is greater than the required remaining battery charge value (W1>W0), grid charging of the battery is performed using at least one of the first frame groups in which the power procurement unit price is lower than the first determination threshold, with the required remaining battery charge value (W0) as the upper limit. [Example 5] The energy storage device further includes a hot water storage type electric water heater (30) that operates using the purchased electricity or the electricity generated by the solar power generation device (50), The aforementioned operating schedule includes determining which of the plurality of frames the electric water heater will perform the water heating operation for storing hot water. The aforementioned operating candidate period includes a default hot water heating candidate period for the hot water heating operation using purchased electricity, which is set in advance and includes nighttime hours. The comparison determination further compares the average value of the power procurement unit price (Pjpx) for the time frame group corresponding to the default water heating candidate period with a second determination threshold (Pt1) which is set to be lower than the power sales unit price to the power grid. The operation schedule for the following day is designed so that, when the average value is higher than the second determination threshold, the water heating operation is performed in a portion of the second group of frames from the default water heating candidate period onward, provided that the amount of electricity used for the water heating operation (WEQpr) can be secured by the surplus of the predicted PV power generation amount (WPVpr) relative to the predicted power consumption amount (WUSpr). The control method according to Example 3 or Example 4, wherein the predicted remaining charge value (W1) of the storage battery is calculated by incorporating the power consumption of the electric water heater when the water heating operation is performed in a part of the second group of frames. [Example 6] The control method described above is The control method according to any one of Examples 3 to 5, further comprising: after determining whether or not grid charging of the battery (40) is to be performed in each frame of the first frame group, creating an operation schedule such that at least some of the frames in the first frame group for which grid charging of the battery is not planned are set as discharge frames in order from the frame with the highest power procurement unit price (Pjpx). [Example 7] The control method described above is The operation schedule is created such that at least one of the plurality of frames, including the discharge reference frame with the highest power procurement unit price (Pjpx), is set as at least one discharge frame on which the battery (40) discharges. The control method according to any one of Examples 2 to 6, wherein the at least one discharge frame is selected in addition to the discharge reference frame based on its positional relationship on the time axis with respect to the discharge reference frame and the power procurement unit price for each frame, within a range in which the total value of the assumed discharge amount (WDP) (WDttl) of the entire discharge frame does not exceed the rated capacity (WBATrt) of the storage battery. [Example 8] The energy storage device further includes a hot water storage type electric water heater (30) that operates using electricity purchased from the power grid (3) or electricity generated by the solar power generation device (50), The aforementioned operating schedule includes determining which of the plurality of frames the electric water heater will perform the water heating operation for storing hot water. The aforementioned operating candidate period includes a default hot water heating candidate period for the hot water heating operation using purchased electricity, which is set in advance and includes nighttime hours. The comparison determination involves comparing the average value of the electricity procurement unit price for the time slot group corresponding to the default water heating candidate period with a first determination threshold (Pt1) that is set to be lower than the electricity sales unit price to the power grid. The control method according to any one of Examples 1 to 4, wherein the operation schedule for the following day is created such that, when the average value is higher than the first determination threshold, the water heating operation is performed in a portion of the second group of frames from the default water heating candidate period onwards, provided that the amount of electricity used for the water heating operation (WEQpr) can be secured by the surplus of the predicted PV power generation amount (WPVpr) relative to the predicted amount of electricity used. [Example 9] A program that, when executed by one or more processors (11), causes the one or more processors to execute the control method described in any one of Examples 1 to 8. [Example 10] An energy management system (100) for a consumer (5) that is able to buy and sell electricity to and from a power grid (3) and is equipped with an electrical load (25), a solar power generation device (50), and energy storage devices (30, 40), A higher-level control device (10) that creates an operating schedule for the energy storage device of the aforementioned customer, The system includes a control device (20) which is installed at the customer's location and generates operation commands for the energy storage device in accordance with the operation schedule created by the higher-level control device, The aforementioned higher-level control device is A means (102) for obtaining the power procurement unit price (Pjpx) of the power system for each of several time slots obtained by dividing the 24 hours of the following day, For each of the aforementioned multiple frames, means (101) for acquiring the predicted PV power generation amount (WPVpr) from the solar power generation device based on the weather forecast information for the following day and the predicted power consumption amount (WUSpr) based on past actual values ​​of power consumption at the consumer, Means (111, 116, 117) for comparing the power procurement unit price in a first group of time slots that belong to a predetermined time period including the default operating candidate period of the energy storage device, with a predetermined first determination threshold (Pt1~Pt3), An energy management system comprising means (119) for creating the next day's operating schedule for the energy storage device based on the predicted PV power generation amount, the predicted power consumption amount, and the results of the comparison determination.

[0218] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended. [Explanation of Symbols]

[0219] Communication network, 3 Power system, 5 Consumers, 9 Server group, 9X, 9Y, 10 Server, 11 Processor, 12 First memory, 13 Second memory, 14 Communication I / F, 15 Input device, 16 Display, 17 Timer, 18 I / O unit, 25 Electrical load, 30 Electric water heater (EcoCute), 40 Storage battery, 50 Solar cell, 100 Energy management system, 101 Prediction information collection unit, 102 Unit price collection unit, 110 Creation processing management unit, 111 Daytime shift control processing, 112 Discharge planning processing unit, 115 Charging planning processing unit, 116 Differential charging processing unit, 117 Charging processing unit, 118 Morning control processing unit, 119 Schedule creation unit, Pjpx JPEX unit price, Pt1, Pt2, Pt3 Judgment threshold, W0 Required storage battery remaining value, W1 Predicted remaining charge (battery), WBATrt Rated capacity (battery), WCBAT Charging energy, WCHgrd Grid charging amount, WCMR Morning discharge capacity, WDBAT Discharge energy, WDP Estimated discharge amount, WDttl Total discharge amount, WDttlf Total discharge amount, WEQpr Daytime shift prediction amount (EcoCute), WPVpr Predicted PV generation amount, WSRpv Predicted PV surplus energy amount, WUSpr Predicted energy consumption amount, Wa Battery remaining charge, Wb Predicted PV surplus energy amount (total).

Claims

1. A control method for energy management targeting a consumer that has an electrical load, a solar power generation device and an energy storage device, and is capable of buying and selling electricity to and from the power grid, Obtain the power procurement unit price for the aforementioned power system for each of the multiple time slots obtained by dividing the 24 hours of the following day, For each of the aforementioned multiple frames, the predicted PV power generation amount from the solar power generation device based on the weather forecast information for the following day and the predicted power consumption amount based on past actual values ​​of the power consumption amount at the consumer are obtained. The process involves comparing the electricity procurement unit price in the first group of time slots, which are among the multiple time slots and which include the default operating candidate period of the energy storage device, with a predetermined first judgment threshold (Pt1 to Pt3). A control method comprising creating an operating schedule for the energy storage device for the following day based on the predicted PV power generation amount, the predicted power consumption amount, and the results of the comparison and determination.

2. The aforementioned energy storage device is The battery includes a battery that can be charged by the surplus power generated by the solar power generation device relative to the power consumption of the customer, or by the power purchased from the power grid, and can supply the customer's power consumption by discharging, The aforementioned operating schedule includes determining whether the battery operates in a charging, discharging, or stopping mode for each of the plurality of time slots. The aforementioned candidate operating period includes the default candidate charging period for the battery using the purchased electricity, which is set during nighttime hours. The comparison determination involves comparing the power procurement unit price of each frame in the first frame group with the first determination threshold (Pt2, Pt3). The control method according to claim 1, wherein the operation schedule for the following day is created such that, in the first group of time slots, grid charging of the battery using purchased electricity is not performed in time slots where the electricity procurement unit price is higher than the first determination threshold.

3. The control method described above is The operation plan for the battery is determined such that at least one discharge time slot in which the battery discharges is set among the plurality of time slots, so that the battery discharges preferentially in time slots with high power procurement costs. The required remaining battery capacity (W0) is calculated by summing the estimated discharge amounts obtained from the predicted PV power generation amount and the predicted power consumption amount in each of the discharge units, The system further comprises calculating the predicted remaining charge (W1) of the battery at the end of power generation for the solar power generation system, using the predicted PV power generation amount and predicted power consumption amount for the plurality of frames, and the remaining charge of the battery at the time the operation schedule for the following day is created. The first determination threshold (Pt2) is set such that, when the required remaining battery charge value is greater than the predicted remaining charge value (W0 > W1), it is lower than the average value of the power procurement unit price in at least one discharge step. The control method according to claim 2, wherein the operation schedule for the following day is created such that, if the required battery remaining capacity is greater than the predicted remaining capacity (W0 > W1), grid charging of the battery is performed using at least a portion of the first group of frames in which the power procurement unit price is lower than the first determination threshold, up to an upper limit of the difference between the required battery remaining capacity and the predicted remaining capacity (W0 - W1).

4. The control method described above is The operation plan for the battery is determined such that at least one discharge time slot in which the battery discharges is set among the plurality of time slots, so that the battery discharges preferentially in time slots with high power procurement costs. The required remaining battery capacity (W0) is calculated by summing the estimated discharge amounts obtained from the predicted PV power generation amount and the predicted power consumption amount in each of the discharge units, The system further comprises calculating the predicted remaining charge (W1) of the battery at the end of power generation for the solar power generation system, using the predicted PV power generation amount and predicted power consumption amount for the plurality of frames, and the remaining charge of the battery at the time the operation schedule for the following day is created. The first determination threshold (Pt3) is set such that, when the predicted remaining charge value is greater than the required remaining charge value of the storage battery (W1 > W0), it becomes lower than the electricity sales price to the power grid. The control method according to claim 2, wherein the operation schedule for the following day is created such that, if the predicted remaining charge value is greater than the required remaining battery charge value (W1 > W0), grid charging of the battery is performed using at least one of the first frame groups in which the power procurement unit price is lower than the first determination threshold, with the required remaining battery charge value (W0) as the upper limit.

5. The energy storage device further includes a hot water storage type electric water heater that operates using the purchased electricity or the electricity generated by the solar power generation device. The aforementioned operating schedule includes determining which of the plurality of frames the electric water heater will perform the water heating operation for storing hot water. The aforementioned operating candidate period includes a default hot water heating candidate period for the hot water heating operation using purchased electricity, which is set in advance and includes nighttime hours. The comparison determination further compares the average value of the power procurement unit price for the time slot group corresponding to the default water heating candidate period with a second determination threshold (Pt1) which is set to be lower than the power sales unit price to the power grid. The operation schedule for the following day is designed so that, when the average value is higher than the second determination threshold, the water heating operation is performed in a portion of the second group of frames from the default water heating candidate period onward, provided that the amount of electricity used for the water heating operation can be secured by the surplus of the predicted PV power generation relative to the predicted amount of electricity used. The control method according to claim 3 or 4, wherein the predicted remaining charge value of the storage battery is calculated by incorporating the power consumption of the electric water heater when the water heating operation is performed in a part of the second group of frames.

6. The control method described above is The control method according to claim 3 or 4, further comprising: after determining whether or not grid charging of the battery is to be performed in each frame of the first frame group, creating an operation schedule such that at least some of the frames in the first frame group for which grid charging of the battery is not planned are set as discharge frames in order from the frame with the highest power procurement cost.

7. The control method described above is The operation schedule is created such that at least one of the plurality of frames, including the discharge reference frame with the highest power procurement unit price, is set as at least one discharge frame on which the battery discharges. The control method according to claim 2, wherein the at least one discharge frame is selected in addition to the discharge reference frame based on its positional relationship on the time axis with respect to the discharge reference frame and the power procurement unit price at each frame, within a range in which the total assumed discharge amount of all discharge frames does not exceed the rated capacity of the storage battery.

8. The energy storage device further includes a hot water storage type electric water heater that operates using electricity purchased from the power grid or electricity generated by the solar power generation device. The aforementioned operating schedule includes determining which of the plurality of frames the electric water heater will perform the water heating operation for storing hot water. The aforementioned operating candidate period includes a default hot water heating candidate period for the hot water heating operation using purchased electricity, which is set in advance and includes nighttime hours. The comparison determination involves comparing the average value of the electricity procurement unit price for the time slot group corresponding to the default water heating candidate period with a first determination threshold (Pt1) that is set to be lower than the electricity sales unit price to the power grid. The control method according to claim 1, wherein the operation schedule for the following day is created such that, when the average value is higher than the first determination threshold, the water heating operation is performed in a portion of the second group of frames from the default water heating candidate period onwards, provided that the amount of electricity used for the water heating operation can be secured by the surplus of the predicted PV power generation relative to the predicted amount of electricity used.

9. A program that, when executed by one or more processors, causes the one or more processors to execute the control method described in any one of claims 1 to 4, 7, and 8.

10. A program that, when executed by one or more processors, causes the one or more processors to execute the control method described in claim 5.

11. A program that, when executed by one or more processors, causes the one or more processors to execute the control method described in claim 6.

12. An energy management system for consumers equipped with electrical loads, solar power generation equipment, and energy storage equipment, capable of buying and selling electricity to and from the power grid, A higher-level control device (10) that creates an operating schedule for the energy storage device of the aforementioned customer, The system includes a control device (20) which is installed at the customer's location and generates operation commands for the energy storage device in accordance with the operation schedule created by the higher-level control device, The aforementioned higher-level control device is A means for obtaining the power procurement unit price of the power system for each of the multiple time slots obtained by dividing the 24 hours of the following day, For each of the aforementioned multiple frames, means for acquiring the predicted PV power generation amount by the solar power generation device based on the weather forecast information for the following day and the predicted power consumption amount based on past actual values ​​of power consumption by the consumer, A means for comparing and determining the power procurement unit price in a first group of time slots that belong to a predetermined time period that includes the default operating candidate period of the energy storage device, among the plurality of time slots, with a predetermined first determination threshold (Pt1 to Pt3), An energy management system comprising means for creating the next day's operating schedule for the energy storage device based on the predicted PV power generation amount, the predicted power consumption amount, and the results of the comparison and determination.

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