Energy management system, energy management method, and energy management program

Abstract

The present invention is an energy management system that realizes energy conservation focusing on a frequency distribution indicating the frequency of energy consumption amounts in an energy demand facility, the energy management system managing consumed energy in the energy demand facility, wherein the energy management system comprises a clustering unit for clustering past energy consumption amounts for the energy demand facility into a plurality of clusters on the basis of a prescribed condition, a modeling unit for modeling a frequency distribution indicating the frequency of the energy consumption amounts in each cluster into a distribution having at least one positive skew, and a schedule adjustment unit for adjusting the operation schedule of the energy demand facility so as to reduce the variance of the modeled distribution.

Description

Energy management system, energy management method, and energy management program

[0001] The present invention relates to an energy management system, an energy management method, and an energy management program.

[0002] BACKGROUND ART Conventionally, energy management systems have been devised for managing energy-consuming facilities such as factory facilities, test facilities, and air conditioning facilities, with the aim of saving energy therein.

[0003] For example, Patent Document 1 discloses an energy usage visualization device that can determine whether energy waste is occurring, identify the causes of the waste, and analyze trends along the production flow of a manufacturing line.

[0004] Furthermore, Non-Patent Document 1 discloses the idea of ​​modeling power demand using power consumption data such as power consumption with or without people present, power consumption with or without experiments, and power consumption demand on weekdays or holidays.

[0005] Japanese Patent Application Laid-Open No. 2013-222256

[0006] MORI, Yuki, and five others, "Short-term Electricity Demand Forecasting for a Laboratory with Non-periodic Electricity Demand Fluctuations," The International Council on Electrical Engineering (ICEE) Conference 2023, published July 2, 2023

[0007] The inventors of the present application have noticed that the frequency distribution showing the frequency of energy consumption in energy demand equipment does not follow a normal distribution, but is instead shown as a distribution with positive skewness, or a combination of multiple distributions with positive skewness.

[0008] The inventors of the present application believe that by reducing the variance in this frequency distribution, it is possible to lower the average value of energy consumption in energy demanding equipment, and ultimately to achieve energy conservation in energy demanding equipment.

[0009] Therefore, the present invention has been made in consideration of the above-mentioned problems, and its main objective is to achieve energy savings by focusing on the frequency distribution that indicates the frequency of energy consumption in energy demand equipment.

[0010] In other words, the energy management system of the present invention is an energy management system that manages energy consumption in energy demand equipment, and is characterized by comprising a clustering unit that clusters the past energy consumption of the energy demand equipment into multiple clusters based on predetermined conditions, a modeling unit that models a frequency distribution indicating the frequency of the energy consumption in each cluster into a distribution having at least one positive skewness, and a schedule adjustment unit that adjusts the operation schedule of the energy demand equipment so as to reduce the variance of the modeled distribution.

[0011] Such an energy management system models the frequency distribution showing the frequency of energy consumption in each cluster as a distribution with at least one positive skewness, and adjusts the operation schedule of the energy demanding equipment to reduce the variance of the modeled distribution, thereby reducing the average energy consumption of the energy demanding equipment, and as a result, achieving energy conservation in the energy demanding equipment.

[0012] As a specific embodiment of the clustering unit, it is desirable that the clustering unit divides the past energy consumption amounts into predetermined unit periods and clusters them into the plurality of clusters.

[0013] Here, the energy demanding facility may include a plurality of energy consuming devices, and in order to efficiently achieve energy conservation in the energy demanding facility, it is desirable that the schedule adjustment unit adjusts the operation schedules of the plurality of energy consuming devices.

[0014] Specifically, it is desirable that the energy demand facility includes a cooling facility, and the schedule adjustment unit adjusts the operation schedule of the cooling facility using a psychrometric chart. With this configuration, it is possible to reduce the variance of the distribution with positive skewness modeled by the modeling unit.

[0015] In order to achieve even greater energy conservation in energy demanding facilities, it is desirable that the schedule adjustment unit predict the load on the cooling facilities and adjust the operation schedule of the cooling facilities using a psychrometric chart.

[0016] As a specific embodiment of a distribution with positive skewness, the distribution with positive skewness may include a power-law distribution in which the median is smaller than the mean.

[0017] In addition, the energy management method of the present invention is an energy management method for managing energy consumption in energy demand equipment, and is characterized in that it clusters the past energy consumption of the energy demand equipment into multiple clusters based on predetermined conditions, models a frequency distribution showing the frequency of the energy consumption in each cluster into a distribution with at least one positive skewness, and adjusts the operation schedule of the energy demand equipment so as to reduce the variance of the modeled distribution.

[0018] Furthermore, the energy management program of the present invention is an energy management program that manages energy consumption in energy demand equipment, and is characterized in that it has a function as a clustering unit that clusters the past energy consumption of the energy demand equipment into multiple clusters based on predetermined conditions, a function as a modeling unit that models a frequency distribution indicating the frequency of the energy consumption in each cluster into a distribution with at least one positive skewness, and a function as a schedule adjustment unit that adjusts the operation schedule of the energy demand equipment so as to reduce the variance of the modeled distribution.

[0019] The energy management program may be distributed electronically or may be recorded on a program recording medium such as a CD, a DVD, or a flash memory.

[0020] According to the present invention as described above, energy conservation can be achieved by focusing on the frequency distribution that indicates the frequency of energy consumption in energy demanding equipment.

[0021] FIG. 1 is an overall schematic diagram of an energy management system according to an embodiment of the present invention. FIG. 2 is data obtained by clustering past energy consumption (histogram by consumption amount). FIG. 3 is a diagram showing a distribution with positive skewness modeled on the frequency distribution of energy consumption at a certain time. FIG. 4 is a schematic diagram showing a distribution modeled on the frequency distribution of energy consumption before schedule adjustment, and a distribution modeled on the frequency distribution of energy consumption before schedule adjustment. FIG. 5 is a diagram showing an example of factor separation of a distribution with positive skewness. FIG. 6 is a diagram showing an example of a screen display of a display in a modified embodiment. FIG. 7 is a diagram showing an example of a screen display of a display in a modified embodiment. FIG. 8 is a diagram showing an example of a screen display of a display in a modified embodiment. FIG. 9 is a diagram showing an example of a screen display of a display in a modified embodiment.

[0022] <One embodiment of the present invention> Hereinafter, one embodiment of an energy management system according to the present invention will be described with reference to the drawings. Note that in all of the drawings shown below, parts are appropriately omitted or exaggerated for clarity. Identical components are assigned the same reference numerals, and descriptions thereof will be omitted as appropriate.

[0023] <Configuration of Energy Management System 100> As shown in FIG. 1, the energy management system 100 of this embodiment manages energy consumption in energy demanding facilities X such as factory facilities, test facilities, or air conditioning facilities.

[0024] Here, the energy demanding facility X has a plurality of energy consuming equipment X1. Examples of the energy consuming equipment X1 include various types of equipment such as manufacturing equipment, processing equipment, conveying equipment, inspection equipment, testing equipment, analytical equipment, air conditioning equipment, and lighting equipment.

[0025] In addition, in this embodiment, the energy consumed by the energy demanding facility X is electricity, but it may be secondary energy other than electricity, such as city gas, propane gas, gasoline, kerosene, or diesel, or primary energy, such as petroleum, coal, wind power, natural gas, hydroelectric power, or geothermal energy.

[0026] Specifically, as shown in FIG. 1, the energy management system 100 includes a clustering unit 10 that clusters the past energy consumption of energy demand equipment X into multiple clusters based on predetermined conditions, a modeling unit 20 that models a frequency distribution indicating the frequency of energy consumption in each cluster into a distribution with at least one positive skewness, and a schedule adjustment unit 30 that adjusts the operation schedule of the energy demand equipment X so as to reduce the variance of the modeled distribution.

[0027] The energy management system 100 is configured by a computer having a CPU, memory, an input / output interface, an AD converter, a display device such as a display, etc. The energy management system 100 performs the functions of the above-mentioned parts by the CPU and peripheral devices working together based on an energy management program stored in the memory. The energy management system 100 may be configured by a physically integrated computer, or may be configured by physically separate computers.

[0028] Each of the units 10 to 30 will be described below. The clustering unit 10 clusters the past energy consumption of the energy demanding facility X into a plurality of clusters based on predetermined conditions. Here, the past energy consumption of the energy demanding facility X is, for example, time-series data of the energy consumption over the past year. This time-series data of the energy consumption is measured, for example, by a wattmeter, and can be stored in the data storage unit 40 of the energy management system 100.

[0029] The clustering unit 10 of this embodiment divides the past energy consumption amounts into a plurality of clusters for each predetermined unit period.

[0030] Here, the predetermined period may be, for example, one or two hours, one or two days, or one or two weeks.

[0031] FIG. 2 shows a histogram (frequency distribution) by consumption, in which time-series data of energy consumption for the past year is plotted on a graph with the vertical axis representing time (hourly) and the horizontal axis representing energy consumption (power consumption [kWh]). Here, the horizontal axis corresponding to each time represents the frequency of energy consumption at that time. In this way, the clustering unit 10 clusters the energy consumption for the past year into 24 clusters, from midnight, 1 a.m., to 11 p.m. The information clustered by the clustering unit 10 (for example, frequency distribution) can be displayed on a display device such as a monitor.

[0032] The modeling unit 20 models a frequency distribution indicating the frequency of energy consumption in a cluster into a distribution with at least one positive skewness. The distribution with positive skewness modeled by the modeling unit 20 of this embodiment includes, for example, a power-law distribution in which the median is smaller than the mean.

[0033] The distribution modeled by the modeling unit 20 is shown in Figure 3. This distribution has positive skewness, and |mean-median| < standard deviation. The distribution modeled by the modeling unit 20 can be displayed on a display device such as a monitor.

[0034] Schedule adjustment unit 30 adjusts the operation schedule of energy demanding facility X based on the distribution modeled by modeling unit 20, based on predetermined conditions, so as to reduce the amount of energy consumption.

[0035] The predetermined condition may be adjusting the operation schedule of energy demanding facility X to reduce the mean value of the modeled distribution. For example, to reduce the mean value of the modeled distribution, the operation schedule of energy demanding facility X may be adjusted to reduce the variance of the modeled distribution.

[0036] Specifically, the schedule adjustment unit 30 adjusts the operation schedules of the plurality of energy consuming appliances X1 so as to coordinate the plurality of energy consuming appliances X1. Here, adjusting the operation schedules may include controlling the plurality of energy consuming appliances X1 in a coordinated manner, or may include outputting the operation schedules of the plurality of energy consuming appliances X1. Furthermore, in the case of a test facility, the operation schedule may include adjusting a test schedule.

[0037] By adjusting the operation schedule by the schedule adjustment unit 30, the variance of the distribution modeled by the modeling unit 20 becomes smaller, and the average value of energy consumption in the energy demanding facility X decreases, as shown in Fig. 4. The operation schedule after adjustment by the schedule adjustment unit 30, the frequency distribution obtained from the adjusted operation schedule, the distribution obtained by modeling the frequency distribution, the average value of energy consumption, or the amount of reduction in energy consumption can be displayed on a display device such as a display.

[0038] <Effects of this embodiment> According to the energy management system 100 of this embodiment configured as described above, the frequency distribution showing the frequency of energy consumption in each cluster is modeled as a distribution with at least one positive skewness, and the operation schedule of the energy demanding equipment is adjusted so as to reduce the variance of the modeled distribution, thereby reducing the average energy consumption of the energy demanding equipment. As a result, energy conservation can be achieved in the energy demanding equipment.

[0039] Other Embodiments For example, the operation schedule adjusted by the schedule adjustment unit 30 of the above embodiment may be configured so that the user can arrange it.

[0040] Furthermore, when adjusting the operation schedule, environmental factors such as weather, customer factors such as product orders, or user factors such as the operator performing the test may be added to the input variables.

[0041] Here, as shown in Fig. 5, when the distribution with positive skewness modeled by the modeling unit 20 was analyzed (factor separation), it was found that it could be decomposed into multiple factors. In particular, the positive skewness portion was dominated by thermal air conditioning (cooling equipment), and it was found that, for example, "factor B" and / or "factor C" in Fig. 5 could be reduced by optimizing the set temperature and / or flow rate of the cooling water of the cooling equipment in the energy demand facility X.

[0042] Therefore, adjusting the operation schedule by the schedule adjustment unit 30 or arranging the operation schedule includes adjusting the set temperature of the cooling water of the cooling equipment in the energy demanding equipment X. Specifically, the schedule adjustment unit 30 adjusts the operation schedule of the cooling equipment using a psychrometric chart. Furthermore, the schedule adjustment unit 30 predicts the load on the cooling equipment and adjusts the operation schedule of the cooling equipment using the psychrometric chart.

[0043] In addition, in energy demand equipment X such as a test facility, the ratio of cooling by cooling water from a cooling facility such as a chiller and heating by steam from a heating facility such as a boiler is adjusted taking into account heat generated by test specimens and the like in the test facility, so that the test environment temperature and / or humidity within the test facility falls within a predetermined test allowable temperature and / or humidity.

[0044] Here, in order to make it easier for a user to adjust the set temperature of the coolant or to confirm whether the adjustment of the set temperature of the coolant is appropriate, as shown in FIG. 6 , the energy management system 100 has a screen display unit that displays, on a display, numerical values ​​such as temperature, humidity, pressure, flow rate, or power of each part of the energy demand facility X, along with a system configuration diagram. FIG. 6 shows a test facility for performing vehicle testing, and the energy demand facility having air conditioning equipment (including cooling equipment and heating equipment) for adjusting the temperature and / or humidity of the test environment of the test facility. Note that vehicle testing includes testing not only of completed vehicles, but also of parts of vehicles (e.g., engines, transmissions, motors, brakes, batteries, fuel cells, etc.), and examples of vehicles include engine vehicles, hybrid vehicles, electric vehicles, and fuel cell vehicles.

[0045] The screen display unit can also display, on the display, for example, graph G, the current test environment temperature and / or humidity of the test facility (here, the test space of the test specimen) along with the progress of the test. This screen display unit displays, on graph G, the current test environment temperature and / or humidity of the test facility as well as the allowable range of temperature and / or humidity (e.g., upper and lower limits). Here, graph G shown in FIG. 6 is a graph of a WLTC test, with the horizontal axis representing time and the left vertical axis representing vehicle speed. Furthermore, the right vertical axis of graph G in FIG. 6 can be set to temperature and / or humidity to display the test environment temperature / humidity.

[0046] In addition, the screen display unit may display, for example, a graph of the temperature and / or humidity of the test equipment (here, the test space of the test specimen) at the current time along with the progress of the test, without displaying numerical values ​​such as the temperature, humidity, pressure, flow rate, or power of each part of the energy demand equipment X together with the system configuration diagram on the display.

[0047] Furthermore, as shown in FIG. 7, the screen display unit can display at least one of the test environment temperature / humidity, outside air temperature / humidity, cooling water temperature, and enthalpy change on a psychrometric chart in real time as the test (test sequence) progresses.

[0048] The following are displayed on the psychrometric chart in Figure 7: "Test allowable range (WLTC test range, e.g., temperature 23±5°C, humidity 50±10%)", "Outside air (OA) (e.g., temperature 30°C, humidity 80%)", "Supply air (SA) setting (e.g., temperature 23°C, humidity 65%)", "Test environment temperature / humidity (= supply air (SA) + (vehicle + equipment) heat generation, e.g., temperature 27.5°C, humidity 47%)", "Outside air (OA) + return air (RA) (e.g., temperature 28.5°C, humidity 65%)", and "Cooling water temperature setting (e.g., temperature 6°C)".

[0049] The psychrometric chart may also display arrows or straight lines connecting the above-mentioned points. Furthermore, the psychrometric chart displays the enthalpy changes of cooling and dehumidification by the cooling equipment, and the enthalpy changes of heating and humidification by the heating equipment. Here, these enthalpy changes are displayed by, for example, arrows.

[0050] By displaying FIG. 7 in this way, the amount of energy (enthalpy) related to the test environment conditions can be visualized on the psychrometric chart.

[0051] 8 shows a diagram (setting change diagram) when the "coolant temperature setting" is changed from 6°C to 15°C. In this diagram, at least one of the test environment temperature / humidity, outside air temperature / humidity, coolant temperature, and enthalpy change can also be displayed on the psychrometric chart. In FIG. 8, at least one of the test environment temperature / humidity, outside air temperature / humidity, coolant temperature, and enthalpy change after the setting change is displayed superimposed on at least one of the test environment temperature / humidity, outside air temperature / humidity, coolant temperature, and enthalpy change before the setting change, but the display method is not limited to this.

[0052] By displaying FIG. 8 in this way, it is possible to visualize the amount of change in energy when the setting parameter (coolant temperature 6°C → 15°C) is changed. It is also possible to verify whether the setting value is appropriate in terms of the amount of energy. Furthermore, it is possible to predict the test environment temperature / humidity when the energy demand changes from the current state. Examples of items that change the energy demand include the outside air temperature / humidity due to time changes, the coolant temperature due to changes in outside air temperature, the heat generated by the vehicle due to changes in the running speed of the vehicle under test, or the heat generated by the vehicle due to a change in vehicle model (from small displacement to large displacement).

[0053] The schedule adjustment unit 30 can also predict the load on the cooling equipment according to the test cycle (here, WLTC) performed in the test facility and adjust the operation schedule of the cooling equipment using a psychrometric chart. Here, the schedule adjustment unit 30 predicts whether the load on the cooling equipment will increase or decrease according to the test cycle (here, WLTC), and adjusts the operation schedule (set temperature change schedule) of the cooling equipment using a psychrometric chart, taking into account the temperature control responsiveness (time constant). Additionally, the schedule adjustment unit 30 can reduce the load between a test cycle (here, WLTC) and the next test cycle (here, WLTC), for example, by raising the set temperature of the cooling equipment. Furthermore, since the load varies for each of the multiple test rooms (test facilities), the schedule adjustment unit 30 can change the set temperature of the cooling equipment for each of the multiple test rooms (test facilities), or can change the set temperature of the cooling equipment according to the number of test rooms (test facilities) in operation.

[0054] The above describes the testing equipment for conducting vehicle tests. However, as shown in FIG. 9, the cooling equipment in the clean room may be configured to make it easier for the user to adjust the set temperature of the cooling water or to make it easier for the user to check whether the adjustment of the set temperature of the cooling water is appropriate.

[0055] Specifically, the energy management system 100 has a screen display unit that displays, along with a system configuration diagram, numerical values ​​such as temperature, humidity, pressure, flow rate, or power of each part of the energy demanding facility X. Fig. 9 shows an energy demanding facility that has a first-stage air conditioning facility that supplies cooled supply air (SA1) to return air (RA) of a clean room (CR), and a second-stage air conditioning facility that cools the supply air (SA1) and the return air (RA).

[0056] Furthermore, as shown in FIG. 10, the screen display unit can display at least one of the CR environmental temperature / humidity, outside air temperature / humidity, coolant temperature, and enthalpy change on a psychrometric chart in real time.

[0057] The following are displayed on the psychrometric chart in Fig. 10: "CR allowable range (e.g., temperature 23±2°C, humidity 50±5%)", "Outdoor air (OA) (e.g., temperature 28°C, humidity 80%)", "Supply air (SA1) setting (e.g., temperature 23°C, humidity 55%)", "Supply air (SA2) setting (e.g., temperature 22°C, humidity 60%)", "CR environment temperature / humidity (= supply air (SA) + equipment heat generation, e.g., temperature 25°C, humidity 50%)", "Supply air (SA1) + return air (RA) (e.g., temperature 24°C, humidity 52%)", "Cooling water temperature setting 1 (for first-stage air conditioning equipment) (e.g., temperature 7°C)", and "Cooling water temperature setting 2 (for second-stage air conditioning equipment) (e.g., temperature 13°C)".

[0058] In addition, when the "cooling water temperature setting 1 (of the first stage air conditioning equipment)" and / or the "cooling water temperature setting 2 (of the first stage air conditioning equipment)" is changed, the screen display unit can display at least one of the CR environmental temperature / humidity, the outside air temperature / humidity, the cooling water temperature, or the enthalpy change on the psychrometric chart.

[0059] By displaying FIG. 10 in this manner, the amount of energy (enthalpy) related to the clean room can be visualized on the psychrometric chart. It is also possible to verify whether the settings of the two-stage air conditioning (first-stage air conditioning equipment and second-stage air conditioning equipment) are appropriate in terms of the amount of energy. Furthermore, it is possible to predict the clean room temperature / humidity when the energy demand changes from the current state. Here, examples of items that change the energy demand include the outside air temperature / humidity due to changes over time, the cooling water temperature due to changes in the outside air temperature, heat generation due to changes in the operating state of the equipment, and / or heat generation due to changes in the number of workers.

[0060] The schedule adjustment unit 30 can also predict the load on the cooling equipment in accordance with the production plan and / or the number of people entering and leaving the clean room, and adjust the operation schedule of the cooling equipment using a psychrometric chart. Here, the schedule adjustment unit 30 predicts whether the load on the cooling equipment will increase or decrease in accordance with the production plan and / or the number of people entering and leaving the clean room, and adjusts the operation schedule of the cooling equipment (schedule for changing the set temperature) using a psychrometric chart, taking into account the responsiveness (time constant) of temperature control.

[0061] The air conditioning equipment of the test facility where the vehicle tests are performed may be of a two-stage air conditioning type similar to the air conditioning equipment of the clean room, or may be of a one-stage air conditioning type similar to the air conditioning equipment of the test facility where the vehicle tests are performed.

[0062] In addition, various modifications and combinations of the embodiments may be made as long as they do not go against the spirit of the present invention.

[0063] According to the present invention, energy conservation can be achieved by focusing on the frequency distribution that indicates the frequency of energy consumption in energy demanding equipment.

[0064] 100: Energy management system X: Energy demand facility X1: Energy consumption device 10: Clustering unit 20: Modeling unit 30: Schedule adjustment unit

Claims

1. An energy management system that manages energy consumption in energy demanding equipment, comprising: a clustering unit that clusters past energy consumption of the energy demanding equipment into multiple clusters based on specified conditions; a modeling unit that models a frequency distribution indicating the frequency of the energy consumption in each cluster into a distribution having at least one positive skewness; and a schedule adjustment unit that adjusts the operation schedule of the energy demanding equipment so as to reduce the variance of the modeled distribution.

2. The energy management system according to claim 1, wherein the clustering unit divides the past energy consumption amounts into a predetermined unit period and clusters the amounts into the plurality of clusters.

3. The energy management system according to claim 1 or 2, wherein the energy demand facility has a plurality of energy consuming devices, and the schedule adjustment unit adjusts the operation schedule of each of the plurality of energy consuming devices.

4. An energy management system as described in any one of claims 1 to 3, wherein the energy demand equipment has cooling equipment, and the schedule adjustment unit adjusts the operation schedule of the cooling equipment using a psychrometric chart.

5. The energy management system according to claim 4, wherein the schedule adjustment unit predicts the load on the cooling equipment and adjusts the operation schedule of the cooling equipment using a psychrometric chart.

6. The energy management system according to any one of claims 1 to 5, wherein the distribution having positive skewness includes a power-law distribution in which the median is smaller than the mean.

7. An energy management method for managing energy consumption in energy demanding equipment, comprising: clustering past energy consumption of the energy demanding equipment into a plurality of clusters based on predetermined conditions; modeling a frequency distribution indicating the frequency of the energy consumption in each of the clusters into a distribution having at least one positive skewness; and adjusting the operation schedule of the energy demanding equipment so as to reduce the variance of the modeled distribution.

8. An energy management program for managing energy consumption in energy demand equipment, comprising: a clustering unit that clusters the past energy consumption of the energy demand equipment into a plurality of clusters based on predetermined conditions; a modeling unit that models a frequency distribution indicating the frequency of the energy consumption in each cluster into a distribution having at least one positive skewness; and a schedule adjustment unit that adjusts the operation schedule of the energy demand equipment so as to reduce the variance of the modeled distribution.

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