Motion control device

Abstract

To provide a motion control device that can control the operation of a power consuming device while minimizing the cost of purchasing power from a power grid.SOLUTION: A motion control device 15 performs a power generation estimation process to derive an estimated amount of power generation that can at least be obtained by a solar cell device 12, a predicted power purchase rate derivation process to derive the ratio of the predicted amount of power purchased to the sum of the estimated amount of power generation and the predicted amount of power purchased as a predicted power purchase rate, a standard power purchase rate derivation process to derive the ratio of the second power purchase price to the sum of the second power purchase price and the power sale price as a standard power purchase rate, and an operation permission / denial decision process to prohibit operation of a specific power consumption device 16 in the power generation unit period when the predicted power purchase rate is greater than the standard power purchase rate, and to permit operation of the specific power consumption device 16 in the power generation unit period when the predicted power purchase rate is equal to or less than the standard power purchase rate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an operation control device for controlling the operation of a device connected to a power line that is interconnected to a power grid. [Background technology]

[0002] There is a system in which a solar cell device and a heat pump water heater are installed in a facility such as a residence or business. For example, Patent Document 1 (JP 2017-116138 A) describes a heat pump water heater that includes a heat pump unit that boils supplied water into hot water and a hot water storage tank that stores the hot water boiled by the heat pump unit, and that is operated using surplus power generated by the solar cell device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-116138 Summary of the Invention [Problem to be solved by the invention]

[0004] By using the system described in Patent Document 1, it is possible to control the operating hours of the heat pump water heater so that it operates during the hours when there is surplus power generated by the solar cell device, which is expected to reduce the operating costs of the heat pump water heater.

[0005] However, if the sun suddenly becomes obscured by clouds, the power generated by the solar cell device drops significantly. Therefore, even if you plan to operate a heat pump water heater using surplus power based on a sunny weather forecast, there is a possibility that the heat pump water heater will actually be operated using purchased power supplied from the power grid. In that case, the operating costs of the heat pump water heater will increase.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide an operation control device that can control the operation of a power consumption device while minimizing the cost of purchasing power from the power grid. [Means for solving the problem]

[0007] A characteristic configuration of an operation control device according to the present invention for achieving the above object is an operation control device for controlling the operation of a power supply system including a solar cell device connected to a power line interconnected to a power grid, a specific power consumption device connected to the power line and subject to control, and a normal power consumption device connected to the power line and not subject to control, wherein the normal power consumption device and the specific power consumption device are configured to, when consuming power as energy, consume power generated by the solar cell device when supplied with the power, and, when power is insufficient, consume purchased power supplied from the power grid in addition to the generated power, and a power generation estimation process for deriving an estimated amount of power generation that can be obtained by the solar cell device during each of a plurality of unit periods constituting one day; a predicted power purchase rate derivation process for deriving a predicted power purchase rate as a predicted power purchase rate to be supplied from the power grid, in each power generation generation unit period, which is a unit period in which the power generation of the solar cell device is predicted to occur, among the plurality of unit periods constituting one day, by subtracting a predicted normal power consumption predicted by the normal power consumption device and a specific power consumption that will occur when the specific power consumption device is operated from the estimated power generation amount; and a standard power purchase rate derivation process that references a first power purchase rate, which is the rate per unit energy of the purchased power supplied from the power grid during a first time period that does not include the power generation unit period within a day, a second power purchase rate, which is the rate per unit energy of the purchased power during a second time period that includes the power generation unit period within a day and is different from the first time period, and a power sale rate, which is the rate per unit energy amount obtained when the generated power is allowed to flow backward to the power grid, and derives, as a standard power purchase rate, the ratio of the second power purchase rate to the sum of the second power purchase rate and the power sale rate, when the first power purchase rate is higher than the power sale rate and lower than the second power purchase rate, and when a composite power purchase rate, which is the unit price of power when the predicted normal power consumption amount and the specified power consumption amount assumed to occur during the power generation unit period are covered by a combination of the generated power and the purchased power, is equal to the first power purchase rate; For each of the power generation generation unit periods, if the predicted power purchase rate derived in the predicted power purchase rate derivation process is greater than the standard power purchase rate derived in the standard power purchase rate derivation process, operation of the specific power consumption device is prohibited during that power generation generation unit period, and if the predicted power purchase rate derived in the predicted power purchase rate derivation process is equal to or less than the standard power purchase rate derived in the standard power purchase rate derivation process, an operation permission / denial decision process is performed to permit operation of the specific power consumption device during that power generation generation unit period. Here, the specific power consuming device may be a device that heats water by a heat pump unit using an electric compressor, or a device that heats water by an electric heater.

[0008] According to the above characteristic configuration, the operation control device can determine for which unit period it is cost-effective to operate a specific power consumption device by taking into account at least the estimated amount of power generated by the solar cell device, i.e., taking into account the possibility that the solar cell device may only be able to generate less power than expected. Therefore, it is possible to provide an operation control device that can control the operation of a power consuming device while minimizing the cost of purchasing power from the power grid.

[0009] A characteristic configuration of an operation control device according to the present invention for achieving the above object is an operation control device for controlling the operation of a power supply system including a solar cell device connected to a power line interconnected to a power grid, a specific energy consumption device connected to the power line and subject to control, capable of operating by consuming electricity and gas fuel as energy, and a normal power consumption device connected to the power line and not subject to control, wherein the normal power consumption device and the specific energy consumption device are configured to, when consuming electricity as the energy, consume the generated power when power generated by the solar cell device is supplied, and, when power is insufficient, consume purchased power supplied from the power grid in addition to the generated power, and a power generation estimation process for deriving an estimated amount of power generation that can be obtained by the solar cell device during each of a plurality of unit periods constituting one day; a predicted power purchase rate derivation process for deriving a predicted power purchase rate as a predicted power purchase rate to be supplied from the power grid, in each power generation generation unit period, which is a unit period in which the generated power of the solar cell device is predicted to be generated, among the plurality of unit periods constituting a day, by subtracting a predicted normal power consumption predicted by the normal power consumption device and a specific power consumption amount that would occur if the specific energy consumption device were operated by consuming only electric power as the energy from the estimated generated power amount; a standard power purchase rate derivation process that, when the gas fuel unit price is higher than the power sale price and lower than the power purchase price, references the power purchase price, which is the rate per unit energy amount of the purchased power, the power sale price, which is the rate per unit energy amount obtained when the generated power is reverse-flowed to the power grid, and the gas fuel unit price when gas is used, which is calculated from the amount of gas necessary to obtain the same output as the unit energy amount by consuming only gas fuel in the specified energy consumption device, and derives, as a standard power purchase rate, the ratio of the power purchase price to the sum of the power purchase price and the power sale price, when the gas fuel unit price is higher than the power sale price and lower than the power purchase price, and when the composite power purchase price, which is the unit price of electricity when the predicted normal power consumption amount and the specified power consumption amount assumed to occur in the power generation unit period are covered by a combination of the generated power and the purchased power, is equal to the gas fuel unit price; If the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is greater than the standard power purchase ratio derived in the standard power purchase ratio derivation process, an operation permission / denial decision process is performed to prohibit the specific energy consumption device from operating by consuming only electricity as the energy during the power generation unit period, and if the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is equal to or less than the standard power purchase ratio derived in the standard power purchase ratio derivation process, an operation permission / denial decision process is performed to permit the specific energy consumption device to operate by consuming only electricity as the energy during the power generation unit period. Here, the specific energy consumption device may be a device that heats water using a heat pump unit that uses an electric compressor, or a device that includes a device that heats water using an electric heater and a combustion device that heats water using heat obtained by burning the gas fuel.

[0010] According to the above characteristic configuration, the operation control device can determine whether it is cost-effective to operate a specific energy consumption device by consuming only electricity as energy during each power generation unit period, while taking into account the possibility that the solar cell device may only generate less power than expected due to changes in weather. Therefore, it is possible to provide an operation control device that can control the operation of a power consuming device while minimizing the cost of purchasing power from the power grid.

[0011] Another characteristic configuration of the operation control device according to the present invention is that, in the generated power estimation process, Collecting solar radiation data consisting of extraterrestrial solar radiation, predicted solar radiation values, and actual measured solar radiation values ​​at each of a plurality of past times; deriving, for each time point of the solar radiation data, a first ratio that is a ratio of the predicted value of the solar radiation to the extraterrestrial solar radiation, and a second ratio that is a ratio of the actual measured value of the solar radiation to the extraterrestrial solar radiation; Classifying the solar radiation data in a form that belongs to one of a plurality of numerical ranges set for the first ratio; deriving a third ratio, which is a ratio of the second ratio to the first ratio for each of the solar radiation amount data belonging to each of the plurality of numerical ranges; The third ratio, when the third ratios of the solar radiation amount data belonging to the numerical range are accumulated in ascending order, is set to a predetermined value from the smallest to the largest, as a conversion ratio from the predicted value of the solar radiation amount corresponding to the numerical range; when the predicted value of the amount of solar radiation and the predicted value of the amount of extra-atmospheric solar radiation at the location where the solar cell device is installed at a target date and time are obtained, determine to which of the plurality of numerical ranges set for the first ratio the ratio of the predicted value of the amount of solar radiation to the predicted value of the amount of extra-atmospheric solar radiation belongs, and derive the product of the predicted value of the amount of solar radiation and the conversion ratio set in the determined numerical range as an estimated value of solar radiation that can be obtained at least at the location where the solar cell device is installed; The present invention derives a transition in estimated power generation obtained at least by the solar cell device based on a transition in the estimated value of the amount of solar radiation.

[0012] Even if a predicted amount of solar radiation is obtained from a weather forecast service or the like, the amount of solar radiation varies depending on the actual weather. However, by referring to past predicted and measured values ​​of solar radiation, it is possible to estimate with a certain degree of probability the amount of solar radiation that can be obtained. For example, it is possible to derive a predetermined conversion ratio and derive the product of the predicted amount of solar radiation and the conversion ratio as the estimated amount of solar radiation that can be obtained. Then, it is possible to derive the estimated amount of power generation per unit period based on the trend of the estimated amount of solar radiation. Therefore, in this characteristic configuration, for each of a plurality of numerical ranges, the third ratio of each solar radiation data belonging to each numerical range is accumulated in ascending order, and the third ratio that results in a predetermined cumulative value is set as the conversion ratio from the predicted solar radiation corresponding to the numerical range. Here, the third ratio is the second ratio (the actual measured solar radiation relative to the extraterrestrial solar radiation) to the first ratio (the predicted solar radiation relative to the extraterrestrial solar radiation). Therefore, when the predicted solar radiation is determined, it is expected that at least the solar radiation (estimated solar radiation) equal to the product of the predicted solar radiation and the conversion ratio can be obtained. Then, the estimated power generation amount for each unit period can be derived based on the trend of the estimated solar radiation. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing a configuration of a power supply system in which an operation control device is provided. [Figure 2] 10 is a flowchart illustrating the operation of the operation control device. [Figure 3] FIG. 10 is a diagram showing an example of a transition of an estimated amount of power generation. [Figure 4] FIG. 10 is a diagram illustrating an example of a transition of predicted normal power consumption. [Figure 5] FIG. 10 is a diagram showing an example of the transition of the total of the predicted normal power consumption and the specified power consumption. [Figure 6] FIG. 10 is a diagram illustrating an example of a transition of a predicted amount of purchased power. [Figure 7]1 is a graph showing the results of analyzing past extraterrestrial solar radiation, predicted solar radiation values, and actually measured solar radiation values. [Figure 8] 10 is a graph showing cumulative values ​​of the presence ratios when solar radiation amount data belonging to the same numerical range are accumulated in ascending order of third ratios. [Figure 9] FIG. 10 is a diagram showing the relationship between the energy unit price when the first power purchase price is higher than the power selling price and lower than the second power purchase price. [Figure 10] FIG. 10 is a diagram showing the relationship between the energy unit price when the gas fuel unit price is higher than the electricity selling price and lower than the electricity purchasing price. DETAILED DESCRIPTION OF THE INVENTION

[0014] First Embodiment A power supply system according to a first embodiment of the present invention will be described below with reference to the drawings. As shown in the figure, the power supply system includes a solar cell device 12 connected to a power line 11 interconnected to a power grid 1, a specific energy consuming device 13 connected to the power line 11, and a normal power consuming device 14 connected to the power line 11. An operation control device 15 is provided in a facility 10, and the specific power consuming device 16 is subject to control by the operation control device 15, while the normal power consuming device 14 is not subject to control by the operation control device 15.

[0015] For example, the operation control device 15 can be realized by a Home Energy Management System (HEMS), etc. In other words, the operation control device 15 is a device that has a function of communicating information with other devices, a processing function of processing information, etc.

[0016] The normal power consumption devices 14 that are not controlled by the operation control device 15 are, for example, lighting devices and air conditioners whose operations are controlled by users of the facility 10.

[0017] In this embodiment, the specific energy consuming device 13 controlled by the operation control device 15 is a specific power consuming device 16 that can operate by consuming electric power as energy. For example, the specific power consuming device 16 is a device that heats water using a heat pump unit that uses an electric compressor, or a device that heats water using an electric heater. The specific power consuming device 16 may also be provided with a hot water storage tank that stores hot water generated by heating water using the heat pump unit or the electric heater. In this case, since heat can be stored in the hot water storage tank, it is possible to operate the specific power consuming device 16 at night and use the generated hot water during the day. In other words, the operation control device 15 is allowed to freely change the time period during which the specific power consuming device 16 operates.

[0018] Alternatively, the specified power consumption device 16 serving as the specified energy consumption device 13 may be an electric vehicle equipped with a storage battery. In this case, the operation control device 15 is allowed to freely change the time period during which the storage battery of the electric vehicle (specified power consumption device 16) that has returned to the facility 10 and is connected to the power line 11 is charged, i.e., the time period during which the electric vehicle is operated.

[0019] The normal power consumption device 14 and the specific power consumption device 16 are connected to the power line 11 to which the power grid 1 and the solar cell device 12 are connected. Therefore, when consuming power as energy, the normal power consumption device 14 and the specific power consumption device 16 operate by consuming the generated power when the power generated by the solar cell device 12 is supplied, and when there is a power shortage, they operate by consuming the generated power as well as purchased power supplied from the power grid 1.

[0020] The facility 10 is also supplied with gas fuel (such as city gas) as energy.

[0021] 1, a facility 10 can communicate with other devices via an information and communication network 2. Therefore, the facility 10 can obtain various information from an information providing server 3 that is also connected to the information and communication network 2.

[0022] For example, the operation control device 15 can determine a unit period during which the specific power consumption device 16 is to operate from among a plurality of unit periods that make up a day, and can instruct the operation of that unit period. It is not easy to determine in which unit period, from among a plurality of unit periods that make up a day, it is cost-effective to operate the specific power consumption device 16, while taking into consideration the possibility that the solar battery device 12 may generate less power than expected due to a change in weather (i.e., the possibility that expensive power purchases may increase).

[0023] Therefore, in this embodiment, the operation control device 15 performs the process shown in the flowchart of FIG. 2 at a predetermined timing, for example, once a day.

[0024] In step #10, the operation control device 15 performs a power generation estimation process to derive an estimated amount of power generation that can be obtained by the solar cell device 12 during each of a plurality of unit periods that make up a day. Fig. 3 is a diagram showing an example of the transition of the estimated amount of power generation. Fig. 3 shows the estimated amount of power generation for each of a plurality of unit times (each hour) that make up a day, but the length of the unit time can be set as appropriate.

[0025] In this embodiment, the operation control device 15 receives information on the transition of predicted solar radiation amounts at the location where the solar cell device 12 is installed and the transition of extraterrestrial solar radiation from the information providing server 3, and stores the information in the storage device 17. Then, the operation control device 15 derives an estimated amount of power generation per unit time that can at least be obtained by the solar cell device 12 based on the information. When estimating the amount of power generation based on the predicted amount of solar radiation, it is necessary to take into consideration that the power generation of the solar cell device 12 will drop significantly if the sun is suddenly obscured by clouds, and to estimate the amount of power generation that can at least be expected to be obtained by the solar cell device 12 even if the sun is suddenly obscured by clouds, rather than the ideal amount of power generation estimated based on the predicted amount of solar radiation (i.e., not assuming a case where the sun is suddenly obscured by clouds).

[0026] 7 is a graph showing the results of analyzing past amounts of extraterrestrial solar radiation, predicted values ​​of solar radiation, and actual measured values ​​of solar radiation. The operation control device 15 collects in advance solar radiation data consisting of amounts of extraterrestrial solar radiation, predicted values ​​of solar radiation, and actual measured values ​​of solar radiation at each of a plurality of past times. Then, for each time of the solar radiation data, the operation control device 15 derives a first ratio, which is the ratio of the predicted value of solar radiation to the amount of extraterrestrial solar radiation, and a second ratio, which is the ratio of the actual measured value of solar radiation to the amount of extraterrestrial solar radiation. In other words, here, the predicted value of solar radiation and the actual measured value of solar radiation are normalized by the amount of extraterrestrial solar radiation.

[0027] The horizontal axis of Figure 7 is the first ratio, which is the ratio of predicted solar radiation to extraterrestrial solar radiation. Therefore, the fewer clouds in the forecast, the larger the first ratio, and the more clouds in the forecast, the smaller the first ratio. In Figure 7, the first ratio is divided into multiple ranges. For example, it is divided into six ranges: range A: "0 < first ratio ≦ 0.2"; range B: "0.2 < first ratio ≦ 0.3"; range C: "0.3 < first ratio ≦ 0.4"; range D: "0.4 < first ratio ≦ 0.5"; range E: "0.5 < first ratio ≦ 0.6"; range F: "0.6 < first ratio ≦ 0.7"; and range G: "0.7 < first ratio ≦ 1.0".

[0028] The vertical axis of Fig. 7 is the second ratio, which is the ratio of the actual measured value of solar radiation to the amount of extra-atmospheric solar radiation. In other words, Fig. 7 plots the relationship between the first ratio, which is the ratio of the predicted value of solar radiation to the amount of extra-atmospheric solar radiation, and the second ratio, which is the ratio of the actual measured value of solar radiation to the amount of extra-atmospheric solar radiation, when the first ratio and the second ratio are derived for each time point for the collected solar radiation data. The operation control device 15 then classifies the solar radiation data so that it belongs to one of a plurality of numerical ranges A to G set for the first ratio. Thereafter, analysis is performed for each group of solar radiation data belonging to the same numerical range.

[0029] First, the operation control device 15 derives, for each of a plurality of numerical ranges, a third ratio, which is the ratio of the second ratio to the first ratio for each piece of solar radiation amount data belonging to that numerical range.

[0030] FIG. 8 is a graph showing the cumulative value of the presence ratio when solar radiation amount data belonging to the same numerical range are accumulated in order from the smallest third ratio. Note that FIG. 8 does not show solar radiation amount data for numerical range A. For example, in the case of numerical range G, when the cumulative value of the presence ratio of solar radiation amount data is 40%, the third ratio is approximately 0.76. This means that the third ratio for 40% of the solar radiation amount data belonging to numerical range G is approximately 0.76 or less. In other words, this means that the third ratio for 60% of the solar radiation amount data belonging to numerical range G is greater than approximately 0.76. Therefore, the lower limit of the third ratio when 60% of the solar radiation amount data belonging to numerical range G is covered is approximately 0.76.

[0031] Similarly, in the case of numerical range F, the third ratio is 0.51 when the cumulative value of the proportion of solar radiation data present is 40%. This means that the third ratio for 40% of the solar radiation data belonging to numerical range F is 0.51 or less. In other words, this means that the third ratio for 60% of the solar radiation data belonging to numerical range F is greater than 0.51. Therefore, the lower limit of the third ratio when 60% of the solar radiation data belonging to numerical range G is covered is 0.51.

[0032] Here, the third ratio is the ratio of the second ratio to the first ratio, i.e., the actual measured solar radiation normalized by extraterrestrial solar radiation to the predicted solar radiation normalized by extraterrestrial solar radiation. Therefore, the third ratio can also be said to indicate the ratio of the actual measured solar radiation to the predicted solar radiation (= actual solar radiation / predicted solar radiation). Therefore, for solar radiation data belonging to numerical range G, there is a 60% probability that the actual measured solar radiation is greater than 0.76 times the predicted solar radiation. Furthermore, for solar radiation data belonging to numerical range F, there is a 60% probability that the actual measured solar radiation is greater than 0.51 times the predicted solar radiation.

[0033] In this way, the operation control device 15 can set the third ratio at which the cumulative value of the presence rate, when the third ratios of the solar radiation amount data belonging to each numerical range are accumulated in ascending order, reaches a predetermined value (such as the value "40%" shown in FIG. 8 and described above) as the conversion ratio from the predicted value of the solar radiation amount corresponding to each numerical range. For example, if the predetermined value is set to 40%, "0.76" is set as the conversion ratio for numerical range G, and "0.51" is set as the conversion ratio for numerical range F. Here, the predetermined value can be freely set and stored in the operation control device 15. Furthermore, the predetermined value of 40% mentioned above is given for illustrative purposes only, and the numerical value can be set as appropriate.

[0034] Then, when the operation control device 15 obtains the predicted value of solar radiation and the predicted value of extra-atmospheric solar radiation at the location where the solar cell device 12 is installed at the target date and time, it determines which of the multiple numerical ranges set for the first ratio the ratio of the predicted value of solar radiation to the predicted value of extra-atmospheric solar radiation belongs to (for example, whether it belongs to numerical range G or numerical range F, etc.), and derives the product of the predicted value of solar radiation and the conversion ratio set in the determined numerical range as an estimated value of solar radiation that will be obtained at least at the location where the solar cell device 12 is installed.

[0035] The operation control device 15 can derive the trend of the estimated solar radiation by performing the above calculations using information on the trend of the predicted value of solar radiation at the location where the solar cell device 12 is installed and the trend of the extraterrestrial solar radiation at the target date and time. Then, the operation control device 15 can derive the trend of the estimated power generation that is expected to be obtained at least by the solar cell device 12 based on the trend of the estimated solar radiation, and can derive the estimated amount of power generation that can be obtained at least by the solar cell device 12 for each unit period, as shown in FIG.

[0036] As described above, even if a predicted amount of solar radiation is obtained from the information providing server 3 that provides a weather forecast service, the amount of solar radiation varies depending on the actual weather. However, by referring to past predicted and measured values ​​of solar radiation, it is possible to estimate with a certain degree of probability the amount of solar radiation that can be obtained. For example, a predetermined conversion ratio can be derived, and the product of the predicted amount of solar radiation and the conversion ratio can be calculated as the estimated amount of solar radiation that can be obtained. Then, the estimated amount of power generation per unit period can be calculated based on the trend of the estimated amount of solar radiation. Therefore, in this embodiment, for each of multiple numerical ranges, the third ratio for which the cumulative value of the presence rate when the respective third ratios of solar radiation data belonging to each numerical range are accumulated in ascending order is set as the conversion ratio from the predicted value of solar radiation corresponding to the numerical range. Here, the third ratio is the second ratio (the actual measured value of solar radiation relative to the amount of extraterrestrial solar radiation) relative to the first ratio (the predicted value of solar radiation relative to the amount of extraterrestrial solar radiation), and therefore corresponds to the ratio of the actual measured value of solar radiation relative to the predicted value of solar radiation. Therefore, when the predicted value of solar radiation is determined, it is expected that at least the solar radiation (estimated solar radiation) will be probabilistically obtained as the product of the predicted value of solar radiation and the above conversion ratio. Then, the estimated amount of power generation per unit period can be derived based on the trend of the estimated solar radiation.

[0037] In step #11, the operation control device 15 performs a predicted power purchase ratio derivation process to derive a predicted power purchase ratio, in which the ratio of the predicted power purchase amount to the sum of the estimated power generation amount and the predicted power purchase amount is used as the predicted power purchase amount to be supplied from the power grid 1, using the predicted power shortage amount obtained by subtracting the predicted normal power consumption predicted by the normal power consumption device 14 and the specific power consumption that will occur when the specific power consumption device 16 is operated from the estimated power generation amount, for each of the power generation generation unit periods, which are unit periods in which power generation by the solar cell device 12 is predicted to occur, out of the multiple unit periods that make up a day.

[0038] FIG. 4 is a diagram showing an example of the transition of predicted normal power consumption. FIG. 5 is a diagram showing an example of the transition of the sum of predicted normal power consumption and specified power consumption. The operation control device 15 stores information about the past transition of power consumption of the normal power consumption device 14 in the storage device 17. Therefore, based on the information about the past transition of power consumption of the normal power consumption device 14, the operation control device 15 can derive the predicted normal power consumption predicted by the normal power consumption device 14 for each power generation generation unit period, which is a unit period during which power generation by the solar cell device 12 is predicted to occur, among multiple unit periods constituting a day, as shown in FIG. 4. In this embodiment, the power generation generation unit period is each unit period between 6:00 and 18:00 during which an estimated amount of power generation is occurring, as shown in FIG. 3.

[0039] Furthermore, the operation control device 15 can read from the storage device 17 the amount of power that will be consumed in a unit period when the specified energy consuming device 13 is operated (i.e., the specified power consumption). As a result, the operation control device 15 can derive the transition of the total of the predicted normal power consumption and the specified power consumption in a power generation unit period, as shown in Fig. 5. Note that Fig. 5 aims to mathematically derive the total of the predicted normal power consumption and the specified power consumption when the specified power consuming device 16 is operated for the entire power generation unit period, and is unrelated to whether or not the specified power consuming device 16 is actually operated in the power generation unit period.

[0040] Next, the operation control device 15 derives the predicted power shortage obtained by subtracting the predicted normal power consumption and the specified power consumption from the estimated power generation amount for each power generation generation unit period as the predicted amount of power purchased from the power grid 1. Fig. 6 corresponds to the predicted power shortage obtained by subtracting the sum of the predicted normal power consumption and the specified power consumption for each unit period shown in Fig. 5 from the estimated power generation amount for each unit period shown in Fig. 3. Since the predicted power shortage is covered by power purchased from the power grid 1, Fig. 6 shows the predicted amount of power purchased for each unit period.

[0041] When the estimated amount of power generation and the predicted amount of power purchase for each unit period are derived as described above, the operation control device 15 derives the ratio of the predicted amount of power purchase to the sum of the estimated amount of power generation and the predicted amount of power purchase as a predicted power purchase ratio. For example, if the estimated amount of power generation and the predicted amount of power purchase are the same, the predicted power purchase ratio is 50%.

[0042] In step #12, the operation control device 15 calculates a first power purchase price, which is the price per unit energy amount of purchased power supplied from the power grid 1 in a first time period (for example, nighttime) that does not include a unit period of power generation in one day, a second power purchase price, which is the price per unit energy amount of purchased power in a second time period (for example, daytime) that includes a unit period of power generation in one day and is different from the first time period, and a unit energy amount obtained when power generated by the solar cell device 12 is allowed to flow backward to the power grid 1. When the first power purchase price is higher than the power sale price and lower than the second power purchase price, and the combined power purchase price, which is the unit price of electricity when the predicted normal power consumption and specific power consumption assumed to occur in a unit power generation period are covered by a combination of the power generated by the solar cell device 12 and the power purchased, is equal to the first power purchase price, a standard power purchase rate derivation process is performed to derive the ratio of the second power purchase price to the sum of the second power purchase price and the power sale price as the standard power purchase rate.

[0043] FIG. 9 is a diagram showing the relationship between energy unit prices. In FIG. 9, the first power purchase price is indicated by a dashed line, and the composite power purchase price, which is the unit price of electricity when electricity generated by the solar cell device 12 and purchased electricity are used together, is indicated by a solid line. The composite power purchase price increases as the proportion of purchased electricity increases. When the first power purchase price is higher than the power selling price and lower than the second power purchase price, if the proportion of purchased electricity (power purchase ratio) is 0% (i.e., the predicted normal electricity consumption amount and the specified electricity consumption amount are covered only by the electricity generated by the solar cell device 12), the composite power purchase price will be equal to the power selling price. On the other hand, if the proportion of purchased electricity (power purchase ratio) is 100% (i.e., the predicted normal electricity consumption amount and the specified electricity consumption amount are covered only by purchased electricity), the composite power purchase price will be equal to the second power purchase price. By thinking in this way, the operation control device 15 can derive the standard power purchase ratio as the ratio of the second power purchase price to the sum of the second power purchase price and the power sale price when the combined power purchase price, which is the unit price of electricity when the predicted normal power consumption and specific power consumption are covered by a combination of the power generated by the solar cell device 12 and the power purchased, is equal to the first power purchase price.

[0044] In the example shown in Fig. 9, the standard power purchase ratio is 30%. That is, in the example shown in Fig. 9, if the ratio of the amount of purchased power is 30% or less, it can be said that it is preferable in terms of cost because it allows the specific power consumption device 16 to operate with power equal to or less than the first power purchase unit price. On the other hand, if the ratio of the amount of purchased power is more than 30%, it means that the specific power consumption device 16 will operate with power higher than the first power purchase unit price, which can be said to be unfavorable in terms of cost.

[0045] Then, in step #13, the operation control device 15 performs an operation permission / denial decision process to prohibit the specific power consumption device 16 from operating during each power generation unit period if the predicted power purchase rate derived in the predicted power purchase rate derivation process is greater than the standard power purchase rate derived in the standard power purchase rate derivation process, and to permit the specific power consumption device 16 to operate during the power generation unit period if the predicted power purchase rate derived in the predicted power purchase rate derivation process is equal to or less than the standard power purchase rate derived in the standard power purchase rate derivation process.

[0046] As described above, the operation control device 15 can determine in which unit period of each power generation generation period it is cost-effective to operate the specific power consumption device 16, while taking into consideration the possibility that the solar cell device 12 may generate less power than expected due to changes in weather.

[0047] Second Embodiment In the first embodiment, an example was described in which the specific energy consuming device 13 is a specific power consuming device 16 that can operate by consuming electric power as energy, but in the second embodiment, a case will be described in which the specific energy consuming device 13 is an apparatus that can operate by consuming electric power and gas fuel as energy. An operation control device 15 of the second embodiment will be described below, but a description of the same configuration as in the above embodiment will be omitted.

[0048] As described above, the specific energy consuming device 13 of this embodiment is a device that can operate by consuming electricity and gas fuel as energy. Note that, although the specific energy consuming device 13 is depicted as the specific power consuming device 16 in Fig. 1, what will be described in this embodiment is not the specific power consuming device 16 but the specific energy consuming device 13 that can operate by consuming electricity and gas fuel as energy. For example, the specific energy consuming device 13 is a device that heats water using a heat pump unit that uses an electric compressor, or a device that heats water using an electric heater and a combustion device that heats water using heat obtained by burning gas fuel.

[0049] Therefore, the specific energy consumption device 13 is allowed to freely change whether it operates by consuming electric power or gas fuel. For example, the operation control device 15 can instruct the specific energy consumption device 13 to operate by consuming only electric power or gas fuel. However, it is not easy to determine whether it is cost-effective to operate by consuming electric power or gas fuel in multiple unit periods that make up a day, while taking into account the possibility that the solar cell device 12 may generate less power than expected due to changes in weather (i.e., the possibility that expensive purchased power may increase).

[0050] Therefore, in this embodiment as well, the operation control device 15 performs the process shown in the flowchart of FIG. 2 at a predetermined timing, for example, once a day.

[0051] In step #10, the operation control device 15 performs a power generation estimation process for each of a plurality of unit periods constituting one day, to derive an estimated amount of power generation that can at least be obtained by the solar cell device 12 during that unit period. The content of this power generation estimation process is the same as that described in the first embodiment.

[0052] In step #11, the operation control device 15 performs a predicted power purchase ratio derivation process to derive a predicted power purchase ratio, which is the ratio of the predicted power purchase amount to the sum of the estimated power generation amount and the predicted power purchase amount, using the predicted power purchase amount as the predicted power purchase amount to be supplied from the power grid 1, as the predicted power purchase amount for each power generation generation unit period, which is a unit period in which power generation by the solar cell device 12 is predicted to occur among the multiple unit periods that make up a day, by subtracting the predicted normal power consumption predicted by the normal power consumption device 14 and the specified power consumption that would occur if the specified energy consumption device 13 were operated consuming only electric power as energy from the estimated power generation amount. The content of this predicted power purchase ratio derivation process is the same as that described in the first embodiment.

[0053] In step #12, the operation control device 15 performs a standard power purchase rate derivation process in which the ratio of the power purchase rate to the sum of the power purchase rate and the power sale rate is calculated as a standard power purchase rate when the gas fuel unit price is higher than the power sale rate and lower than the power purchase rate, and the composite power purchase rate, which is the unit price of electricity when the predicted normal power consumption and specific power consumption assumed to occur in a unit power generation period are covered by both the power generated by the solar cell device 12 and the power purchased, is equal to the gas fuel unit price, by referring to the power purchase rate, which is the charge per unit energy amount of purchased power, the power sale rate, which is the charge per unit energy amount obtained when the power generated by the solar cell device 12 is flowed backward to the power grid 1, and the gas fuel unit price when gas is used, which is calculated from the amount of gas required to obtain the same output as the unit energy amount by consuming only gas fuel in the specific energy consumption device 13.

[0054] FIG. 10 is a diagram showing the relationship between energy unit prices. In FIG. 10, the gas fuel unit price is shown by a dashed line, and the composite power purchase price, which is the unit price of electricity when electricity generated by the solar cell device 12 and purchased electricity are used together, is shown by a solid line. The composite power purchase price increases as the proportion of purchased electricity increases. When the gas fuel unit price is higher than the electricity selling price and lower than the electricity purchasing price, if the proportion of purchased electricity (power purchase ratio) is 0% (i.e., the predicted normal power consumption and the specified power consumption are covered only by the electricity generated by the solar cell device 12), the composite power purchase price will be equal to the electricity selling price. On the other hand, if the proportion of purchased electricity (power purchase ratio) is 100% (i.e., the predicted normal power consumption and the specified power consumption are covered only by purchased electricity), the composite power purchase price will be equal to the electricity purchasing price. By thinking in this way, the operation control device 15 can derive the standard power purchase ratio as the ratio of the combined power purchase price, which is the unit price of electricity when the predicted normal power consumption and specific power consumption are covered by a combination of the power generated by the solar cell device 12 and the power purchased, to the sum of the power purchase price and the power sale price when the combined power purchase price is equal to the gas fuel unit price.

[0055] In the example shown in Fig. 10, the standard power purchase ratio is 30%. In other words, in the example shown in Fig. 10, if the ratio of the amount of purchased power is 30% or less, it can be said that it is preferable from a cost perspective because the specific energy consuming device 13 can be operated with power that is equal to or less than the unit price of gas fuel. On the other hand, if the ratio of the amount of purchased power is more than 30%, it can be said that it is not preferable from a cost perspective because the specific energy consuming device 13 will be operated with power that is higher than the unit price of gas fuel.

[0056] Then, in step #13, if the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is greater than the standard power purchase ratio derived in the standard power purchase ratio derivation process, the operation control device 15 prohibits the specific energy consumption device 13 from operating by consuming only electricity as energy during the power generation unit period (i.e., permits it to operate by consuming only gas fuel), and if the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is equal to or less than the standard power purchase ratio derived in the standard power purchase ratio derivation process, performs an operation permission / denial decision process to permit the specific energy consumption device 13 to operate by consuming only electricity as energy during the power generation unit period.

[0057] As described above, the operation control device 15 can determine whether it is cost-effective to operate the specific energy consumption device 13 by consuming only electricity as energy during each power generation unit period, while taking into account the possibility that the solar cell device 12 may only generate less power than expected due to changes in weather.

[0058] <Another embodiment> In the above embodiment, the configuration of the operation control device 15 and the power supply system in which it is installed has been specifically described, but the configuration can be changed as appropriate. For example, the functions of the operation control device 15 may be realized by a server external to the facility 10.

[0059] In the above embodiment, several specific examples of the specific energy consuming apparatus 13 are given, but the type of apparatus to be operated as the specific energy consuming apparatus 13 can be changed as appropriate.

[0060] In the above embodiment, an example in which the unit period is one hour has been described, but the length of the unit period can be set as appropriate. For example, the length of the unit period may be set to 30 minutes.

[0061] The configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0062] The present invention can be used in an operation control device that can control the operation of a power consuming device while minimizing the cost of purchasing power from the power grid. [Explanation of symbols]

[0063] 1: Power system 2: Information and communication network 3: Information server 10: Facilities 11: Power lines 12: Solar cell device 13: Specific energy consumption device 14: Normal power consumption device 15: Motion control device 16: Specific power consumption device (Specific energy consumption device 13) 17:Storage device

Claims

1. In a power supply system comprising a solar cell device connected to a power line interconnected to a power grid, a specific power consumption device connected to the power line and subject to control, and a normal power consumption device connected to the power line and not subject to control, the normal power consumption device and the specific power consumption device are configured to, when consuming power as energy, operate by consuming power generated by the solar cell device when the power generated by the solar cell device is supplied, and, when power is insufficient, operate by consuming purchased power supplied from the power grid in addition to the generated power, the power supply system comprises an operation control device for controlling operation of the specific power consumption device, a power generation estimation process for deriving an estimated amount of power generation that can be obtained by the solar cell device during each of a plurality of unit periods constituting one day; a predicted power purchase rate derivation process for deriving a predicted power purchase rate as a predicted power purchase rate to be supplied from the power grid, in each power generation generation unit period, which is a unit period in which the generated power of the solar cell device is predicted to be generated, among the plurality of unit periods constituting one day, by subtracting a predicted normal power consumption predicted by the normal power consumption device and a specific power consumption that will occur when the specific power consumption device is operated from the estimated power generation amount; and a standard power purchase rate derivation process that references a first power purchase rate, which is a rate per unit energy of the purchased power supplied from the power grid during a first time period that does not include the power generation unit period within a day; a second power purchase rate, which is a rate per unit energy of the purchased power during a second time period that includes the power generation unit period within a day and is different from the first time period; and a power sale rate, which is a rate per unit energy amount obtained when the generated power is allowed to flow backward to the power grid, and when the first power purchase rate is higher than the power sale rate and lower than the second power purchase rate, derives a standard power purchase rate as a ratio of the second power purchase rate to the sum of the second power purchase rate and the power sale rate when a composite power purchase rate, which is a unit price of power when the predicted normal power consumption amount and the specified power consumption amount assumed to occur during the power generation unit period, are covered by a combination of the generated power and the purchased power, is equal to the first power purchase rate; and an operation control device that performs an operation permission / denial decision process for prohibiting the operation of the specific power consumption device during each power generation unit period if the predicted power purchase rate derived in the predicted power purchase rate derivation process is greater than the standard power purchase rate derived in the standard power purchase rate derivation process, and permitting the operation of the specific power consumption device during the power generation unit period if the predicted power purchase rate derived in the predicted power purchase rate derivation process is equal to or less than the standard power purchase rate derived in the standard power purchase rate derivation process.

2. 2. The operation control device according to claim 1, wherein the specific power consumption device is a device that heats water by a heat pump unit using an electric compressor, or a device that heats water by an electric heater.

3. a solar cell device connected to a power line interconnected to a power grid; a specific energy consumption device connected to the power line, controlled and operable by consuming electricity and gas fuel as energy; and a normal power consumption device connected to the power line and not controlled, wherein the normal power consumption device and the specific energy consumption device are configured to consume generated power from the solar cell device when supplied with the generated power when consuming electricity as the energy, and to consume purchased power supplied from the power grid in addition to the generated power when there is a power shortage; an operation control device for controlling the operation of the specific energy consumption device, a power generation estimation process for deriving an estimated amount of power generation that can be obtained by the solar cell device during each of a plurality of unit periods constituting one day; a predicted power purchase rate derivation process for deriving a predicted power purchase rate as a predicted power purchase rate to be supplied from the power grid, in each power generation generation unit period, which is a unit period in which the generated power of the solar cell device is predicted to be generated, among the plurality of unit periods constituting one day, by subtracting a predicted normal power consumption predicted by the normal power consumption device and a specific power consumption amount that would occur if the specific energy consumption device were operated by consuming only electric power as the energy from the estimated power generation amount; a standard power purchase rate derivation process that, when the gas fuel unit price is higher than the power sale price and lower than the power purchase price, references the power purchase price, which is the rate per unit energy amount of the purchased power, the power sale price, which is the rate per unit energy amount obtained when the generated power is reverse-flowed to the power grid, and the gas fuel unit price when gas is used, which is calculated from the amount of gas necessary to obtain the same output as the unit energy amount by consuming only gas fuel in the specified energy consumption device, and derives, as a standard power purchase rate, the ratio of the power purchase price to the sum of the power purchase price and the power sale price, when the gas fuel unit price is higher than the power sale price and lower than the power purchase price, and when the combined power purchase price, which is the unit price of electricity when the predicted normal power consumption amount and the specified power consumption amount assumed to occur in the power generation unit period, are covered by a combination of the generated power and the purchased power, is equal to the gas fuel unit price; an operation control device that performs an operation permission / denial decision process that prohibits the specific energy consumption device from operating by consuming only electricity as the energy source during the power generation unit period if the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is greater than the standard power purchase ratio derived in the standard power purchase ratio derivation process, and permits the specific energy consumption device to operate by consuming only electricity as the energy source during the power generation unit period if the predicted power purchase ratio derived in the predicted power purchase ratio derivation process is equal to or less than the standard power purchase ratio derived in the standard power purchase ratio derivation process.

4. 4. The operation control device according to claim 3, wherein the specific energy consumption device is a device that heats water using a heat pump unit that uses an electric compressor, or a device that heats water using an electric heater, and a combustion device that heats water using heat obtained by burning the gas fuel.

5. In the generated power estimation process, Collecting solar radiation data consisting of extraterrestrial solar radiation, predicted solar radiation values, and actual measured solar radiation values ​​at each of a plurality of past times; deriving, for each time point, a first ratio that is a ratio of a predicted value of the solar radiation to the extraterrestrial solar radiation, and a second ratio that is a ratio of an actual measured value of the solar radiation to the extraterrestrial solar radiation, for the solar radiation amount data; Classifying the solar radiation data into one of a plurality of numerical ranges set for the first ratio; deriving a third ratio, which is a ratio of the second ratio to the first ratio for each of the solar radiation amount data belonging to each of the plurality of numerical ranges; the third ratio, when the third ratios of the solar radiation amount data belonging to the numerical range are accumulated in ascending order, is set to a predetermined value from the smallest to the largest, as a conversion ratio from the predicted value of the solar radiation amount corresponding to the numerical range; When the predicted value of the amount of solar radiation and the predicted value of the amount of extra-atmospheric solar radiation at the location where the solar cell device is installed at a target date and time are obtained, a ratio of the predicted value of the amount of solar radiation to the predicted value of the amount of extra-atmospheric solar radiation is determined to which of the plurality of numerical ranges set for the first ratio belongs, and a product of the predicted value of the amount of solar radiation and the conversion ratio set in the determined numerical range is derived as an estimated value of solar radiation that can be obtained at least at the location where the solar cell device is installed; 5. The operation control device according to claim 1, further comprising: a controller for deriving a transition of estimated power generation obtained at least by the solar cell device based on a transition of the estimated value of solar radiation.

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