Electricity rate design system and electricity rate design method

Abstract

We provide an electricity rate design system that designs a combination of fixed and variable rates in a way that allows consumers to judge the effectiveness of reducing their electricity costs. [Solution] The electricity rate design system 21 includes a variable equipment operation plan calculation unit 108 that calculates the operation plan and electricity costs of the variable equipment 103 by applying a variable rate or a fixed rate under the estimated operating conditions of the variable equipment 103; a non-variable equipment electricity cost calculation unit 112 that calculates the electricity costs of the non-variable equipment 109 by applying a variable rate or a fixed rate to non-variable equipment measurement data; and an electricity cost aggregation unit 113 that aggregates the electricity costs calculated by the variable equipment operation plan calculation unit 108 and the electricity costs calculated by the non-variable equipment electricity cost calculation unit 112 and presents this aggregated data to consumers as electricity rate design data.

Description

Technical Field

[0001] The present invention relates to an electricity charge design system and an electricity charge design method.

Background Art

[0002] The electricity charge that a retail electricity business operator charges a customer who uses electricity generally consists of a basic charge determined by the contract capacity and an electricity quantity charge calculated according to the amount of electricity used. Usually, the electricity quantity charge is calculated using the unit price per kWh (hereinafter referred to as the "kWh unit price"). A retail electricity business operator is, for example, an operator who procures electricity through electricity market transactions or bilateral transactions and mediates the sale and purchase of electricity. A customer is generally a person who consumes electricity, such as a factory, a household, or a building.

[0003] The electricity quantity charge is designed taking into account the wholesale electricity trading market, procurement costs from power generation companies, entrusted transmission costs paid to transmission and distribution companies, supply and demand management costs required for the planned value at the same time and the same quantity, etc. Among these costs, when a retail electricity business operator procures electricity from the wholesale electricity trading market, the procurement unit price per unit kWh (for example, 1 kWh) changes with the date and time. For example, in the short term, the procurement unit price tends to decrease during the daytime when the power generation amount of solar power generation increases, and tends to increase in the evening when the power generation amount of solar power generation decreases and the power generation amount of thermal power generation increases. Also, in the long term, the procurement unit price increases or decreases due to the influence of fuel prices such as LNG (Liquefied Natural Gas). In the design of electricity charges, these short-term and long-term procurement unit price fluctuations are also taken into account.

[0004] The electricity quantity charge is roughly classified into a fixed charge and a variable charge. Here, the fixed charge refers to a charge with a constant kWh unit price regardless of the time zone when electricity is used. The variable charge refers to a charge with a changing kWh unit price depending on the time zone when electricity is used.

[0005] Fixed rates partially reflect fluctuations in procurement costs in the form of fuel cost adjustments and market price adjustments. However, since fluctuations in procurement costs are settled on a monthly basis for fixed rates, they do not have the effect of inducing consumers to use electricity during off-peak hours when market prices are low. In contrast, variable rates, with their time-varying kWh price, have a demand-shifting effect that induces consumers to use electricity during off-peak hours when market prices are low.

[0006] Variable rates are classified into time-of-day rates, where the kWh price changes during the day but not daily, and constant rates, where the price changes daily. A typical example of time-of-day rates is the nighttime discount electricity rate plan, which lowers the kWh price at night to utilize surplus electricity at night. There are also daytime discount electricity rate plans, which lower the kWh price during daytime hours, due to the expansion of solar power generation. A typical example of constant rates is the market-linked rate, where the kWh price is linked to the procurement price (for example, the 30-minute contract price in the market a day in advance). Market-linked rates are a mechanism that passes on the risk of fluctuations in market procurement prices directly to consumers without the retail electricity provider bearing the risk.

[0007] As prior art concerning a combination of fixed and variable rates, Patent Document 1 discloses a form of applying multiple electricity rate plans to a single customer.

[0008] Patent Document 1 states that "electricity demand information is divided into base electricity demand information, which represents the standard electricity demand based on minimum electricity usage, and load-following electricity demand information, which represents the electricity demand that follows or fluctuates according to the load (specifically, the amount of electricity used)." It also states that "when the electricity demand information is divided, the total electricity charge, which is the sum of the first electricity charge based on the first rate plan information and the base electricity demand information, and the second electricity charge based on the second rate plan information and the load-following electricity demand information, is calculated sequentially for each of the following three cases. The first case is when the first rate plan information is contracted for a specific contracted power. The second case is when the electricity is contracted for a predetermined amount increased from that specific contracted power. The third case is when the electricity is contracted for a predetermined amount decreased from that specific contracted power." Patent Document 1 also lists demand response (DR) type rate plan information, which is a type of variable rate, as one of the applicable rate plans. Here, DR is defined as "a system that sets electricity rates by time of day and encourages reduced usage by paying consumers who refrain from using electricity during peak hours, thereby reducing peak electricity consumption and ensuring a stable supply of electricity." [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Patent No. 6711077 [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] As mentioned above, a method has been disclosed for reducing a customer's electricity costs by applying both fixed and variable rates to a single customer. However, in the example in Patent Document 1, although the target to which different rate plans are applied is divided into base power demand and load-following power demand, the variability of individual electrical equipment that uses electricity is not mentioned. For example, if the electrical equipment is variable equipment whose power consumption can be changed, electricity costs can be reduced by applying variable rates. However, if the electrical equipment is not variable equipment whose power consumption cannot be changed, the period of high power consumption may coincide with the period of high kWh unit price, which may actually increase electricity costs. Alternatively, if variable and non-variable equipment are mixed, a trade-off may arise where a variable rate designed to reduce the electricity costs of variable equipment increases the electricity costs of non-variable equipment. This problem is not limited to the example in Patent Document 1, but can similarly occur when variable rates are applied without distinguishing between electrical equipment downstream of the point of power reception.

[0011] This invention was made in view of these circumstances, and aims to design a combination of fixed and variable charges in a way that allows consumers to judge the effect of reducing electricity costs. [Means for solving the problem]

[0012] The electricity rate design system according to the present invention includes a variable rate database storing variable rate unit price data, a fixed rate database storing fixed rate unit price data, a variable device measurement database storing variable device measurement data acquired from a variable device measurement device that measures the amount of energy used by a customer's variable device, a variable device specification database storing variable device specification data, an operating condition estimation unit that estimates the operating conditions of the variable device based on the variable device measurement data and the variable device specification data, and a variable rate design system that applies variable rates or fixed rates under the operating conditions. The system comprises: a variable equipment operation plan calculation unit that calculates the operation plan and electricity costs of equipment; a variable equipment measurement database that stores variable equipment measurement data acquired from a variable equipment measurement device that measures the amount of energy used by the customer's non-variable equipment; a non-variable equipment electricity cost calculation unit that calculates the electricity costs of non-variable equipment by applying variable or fixed charges to the non-variable equipment measurement data; and an electricity cost aggregation unit that aggregates the electricity costs calculated by the variable equipment operation plan calculation unit and the electricity costs calculated by the non-variable equipment electricity cost calculation unit and presents this aggregated data to the customer as electricity rate design data. [Effects of the Invention]

[0013] According to the present invention, a combination of fixed and variable charges can be designed in a way that allows consumers to judge the effect of reducing electricity costs. Other issues, configurations, and effects not mentioned above will be clarified by the following description of the embodiments. [Brief explanation of the drawing]

[0014] [Figure 1] This is a block diagram showing an example of the functional configuration of a power rate design system according to the first embodiment of the present invention. [Figure 2] This is a block diagram showing an example of the hardware configuration of a power rate design system according to the first embodiment of the present invention. [Figure 3] This graph shows the calculation procedure for the demand shift operation plan in the electricity rate design system according to the first embodiment of the present invention. [Figure 4]This is a table showing an example of the configuration of a tariff plan in the electricity tariff design system according to the first embodiment of the present invention. [Figure 5] This is a graph showing the comparison of tariff plans in the electricity tariff design system according to the first embodiment of the present invention. [Figure 6] This is a graph showing the comparison of tariff plans in the electricity tariff design system according to the first embodiment of the present invention. <� [Figure 7] This is a graph showing the comparison of tariff plans in the electricity tariff design system according to the first embodiment of the present invention. [Figure 8] This is a graph showing the suitability of a tariff plan in the electricity tariff design system according to the first embodiment of the present invention. [Figure 9] This is a flowchart showing the procedure for comparing tariff plans in the electricity tariff design system according to the first embodiment of the present invention. [Figure 10] This is a data table of electricity tariff design data in the electricity tariff design system according to the first embodiment of the present invention. [Figure 11] This is a block diagram showing an example of the functional configuration of the electricity tariff design system according to the second embodiment of the present invention. [Figure 12] This is a graph showing the quantification of the breakdown of the unit price per kWh in the electricity tariff design system according to the second embodiment of the present invention. [Figure 13] This is a graph showing the adjustment of the breakdown of the unit price per kWh in the electricity tariff design system according to the second embodiment of the present invention. [Figure 14] This is a graph showing the adjustment of the variable tariff in the electricity tariff design system according to the second embodiment of the present invention. [Figure 15] This is a graph showing the comparison of tariff plans and the adjustment of electricity costs in the electricity tariff design system according to the second embodiment of the present invention. [Figure 16] This is a data table of electricity tariff design data in the electricity tariff design system according to the second embodiment of the present invention. [Figure 17] This is a data table of the variable tariff before and after adjustment in the electricity tariff design system according to the second embodiment of the present invention. [Figure 18] A graph showing the gain distribution of players in the electricity charge design system according to the second embodiment of the present invention.

Embodiments for Carrying out the Invention

[0015] Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same function or configuration are denoted by the same reference numerals, and redundant descriptions are omitted.

[0016] <First Embodiment> FIG. 1 is a block diagram showing a functional configuration example of an electricity charge design system 21 according to the present embodiment. The electricity charge design system 21 is composed of equipment on the operator side including a retail electricity business operator and equipment on the customer side.

[0017] The equipment on the operator side includes a variable charge database 101, a fixed charge database 102, a variable equipment measurement database 105, a variable equipment specification database 106, an operating condition estimation unit 107, a variable equipment operation plan calculation unit 108, a non-variable equipment power cost calculation unit 112, and a power cost aggregation unit 113. In the figure, each database is abbreviated as DB.

[0018] The variable charge database 101 stores the kWh unit price of the variable charge in the form of time series data as the kWh unit price data of the variable charge (an example of the electricity quantity unit price data of the variable charge).

[0019] The fixed charge database 102 stores the kWh unit price of the fixed charge as the kWh unit price data of the fixed charge (an example of the electricity quantity unit price data of the fixed charge). The kWh unit price data of the fixed charge is scalar data if the fixed charge does not change throughout the year, but is stored in the fixed charge database 102 in the form of time series data if the fuel cost adjustment amount or market price adjustment amount that changes monthly is taken into account.

[0020] The customer-side equipment includes a variable device 103, a variable device measuring device 104, a non-variable device 109, and a non-variable device measuring device 110, which are shown enclosed by dashed lines in the figure.

[0021] The customer's variable equipment 103 includes, for example, thermal storage equipment such as thermal storage air conditioning systems and hot water supply heat pumps, energy storage equipment such as batteries and EVs (Electric Vehicles), production lines whose production schedules can be changed, and P2G (Power to Gas) plants that produce fuels such as hydrogen.

[0022] The variable equipment measuring device 104 measures the amount of energy used by the customer's variable equipment 103. The amount of energy used is, for example, the amount of electricity used by the variable equipment 103. The variable equipment measuring device 104 also measures equipment usage data, such as the amount of hot water stored in a hot water storage type heat pump.

[0023] The variable device measurement database 105 stores variable device measurement data measured by the variable device measurement device 104 and acquired from the variable device measurement device 104. The variable device measurement data is, for example, power consumption data representing the amount of power consumed by the variable device 103.

[0024] The variable equipment specification database 106 stores specification data representing the specifications of the variable equipment 103. For example, if the variable equipment 103 is a hot water storage type heat pump, the specification data stored in the variable equipment specification database 106 would include the hot water storage tank capacity, heat pump output, and heat pump efficiency.

[0025] The operating condition estimation unit 107 estimates the operating conditions of the variable equipment 103 based on the variable equipment measurement data stored in the variable equipment measurement database 105 and the specification data stored in the variable equipment specification database 106, using a method described later. Operating conditions include, for example, the time change in heat demand associated with hot water use in the case of a hot water storage type heat pump, and in the case of an EV, the timing of entry and exit and the required amount of charge. Alternatively, operating conditions may include, for example, the production volume required by a predetermined deadline in the case of a production line or plant.

[0026] The variable equipment operation plan calculation unit 108 calculates the operation plan and electricity costs for the variable equipment 103, applying variable or fixed charges under the operating conditions estimated by the operation condition estimation unit 107. For example, the variable equipment operation plan calculation unit 108 calculates an operation plan that minimizes electricity costs under the operating conditions, using the variable charges stored in the variable charge database 101 and the fixed charges stored in the fixed charge database 102, by the method described later. Then, the variable equipment operation plan calculation unit 108 calculates the electricity costs based on the calculated operation plan and outputs these electricity costs to the electricity cost aggregation unit 113.

[0027] For example, with regard to a storage-type hot water heat pump, even if the amount of electricity used and the amount of hot water stored can be measured as operational results, it is not possible to know under what operating conditions those amounts of electricity used and hot water stored. Without knowing the operating conditions, it is not possible to know what other operating plans can be taken besides the measured operational results, that is, the degree of freedom for demand shifting. However, by estimating the operating conditions of the variable equipment 103 using the operating condition estimation unit 107, the variable equipment operation plan calculation unit 108 can calculate an operating plan for the variable equipment 103.

[0028] The customer's non-variable equipment 109 includes, for example, business or living facilities that are operated on a case-by-case basis according to the workflow or lifestyle, and that do not allow for energy storage, heat storage, or demand shifting. The non-variable equipment measuring device 110 measures the amount of power consumed by the non-variable equipment 109. The variable-rate instrument measurement database 111 stores data measured by the variable-rate instrument measurement device 110.

[0029] The variable equipment power cost calculation unit 112 calculates the power cost of the variable equipment 109 by applying variable or fixed rates to the variable equipment measurement data. For example, the variable equipment power cost calculation unit 112 multiplies the amount of electricity used by the variable equipment 109 stored in the variable equipment measurement database 111 by the kWh unit price of the variable rate stored in the variable rate database 101, and then by the kWh unit price of the fixed rate stored in the fixed rate database 102. In this way, the variable equipment power cost calculation unit 112 calculates the power cost of the variable equipment 109 for both variable and fixed rates, and outputs the calculated power cost to the power cost aggregation unit 113. Here, the expression "multiplying" is used for the amount of electricity used, which is time-series data, and the kWh unit price of the variable rate, which is also time-series data. This expression means the sum of the products of the time-series data, that is, the dot product calculation when the two are viewed as vectors. In this specification, multiplication of time series data means the same dot product calculation unless otherwise specified, for example, by explicitly indicating a particular element of the time series data.

[0030] The power cost aggregation unit 113 aggregates the power costs based on the operation plan calculated by the variable equipment operation plan calculation unit 108 and the power costs calculated by the non-variable equipment power cost calculation unit 112, and presents the aggregated power costs to the consumer as power rate design data. Power rate design data is data used for reaching an agreement between the retail electricity provider, which is the entity responsible for designing power rates, and the consumer, which is the entity responsible for selecting power rates. The agreement between the retail electricity provider and the consumer on what kind of power contract to conclude is called reaching an agreement. Furthermore, "aggregation" means aggregating the costs calculated by the variable equipment operation plan calculation unit 108 and the non-variable equipment power cost calculation unit 112, as shown in Figure 15, which will be described later.

[0031] The power cost aggregation unit 113 may receive the operation plan from the variable equipment operation plan calculation unit 108 and provide the operation plan to the customer along with the power rate design data. In addition to the power costs shown in Figure 5 and later, the customer can also check the operation plan.

[0032] Figure 2 is a block diagram showing an example of the hardware configuration of the electricity rate design system 21 according to the first embodiment.

[0033] The electricity rate design system 21 comprises an input / output device 211, a communication device 212, a computing device 213, and a storage device 214. The electricity rate design system 21 is implemented on computer hardware owned by the retail electricity provider, or on cloud computing hardware used by the retail electricity provider.

[0034] The input / output device 211 is used to set variable rates stored in the variable rate database 101, fixed rates stored in the fixed rate database 102, and specification data stored in the variable equipment specification database 106. The input / output device 211 is also used to present the electricity rate design data aggregated by the electricity cost aggregation unit 113 to the retail electricity provider, which is the entity responsible for designing electricity rates. The input / output device 211 may include, for example, a liquid crystal display monitor that displays processing results, etc., to the user of the electricity rate design system 21. The input / output device 211 may also include, for example, a keyboard, mouse, etc., that allow the user of the electricity rate design system 21 to perform predetermined operation inputs and instructions.

[0035] The communication device 212 receives measurement data measured by the variable equipment measuring device 104 and the non-variable equipment measuring device 110 from the customer system 22 via the communication device 222. It also transmits electricity rate design data aggregated by the power cost aggregation unit 113 to the communication device 222. The communication device 212 may be a NIC (Network Interface Card), for example. The communication device 212 can send and receive various types of data between devices via a LAN (Local Area Network), the Internet, a dedicated line, etc., connected to the terminals of the NIC.

[0036] The arithmetic unit 213 is responsible for the calculation processing of the aforementioned operating condition estimation unit 107, variable equipment operation plan calculation unit 108, non-variable equipment power cost calculation unit 112, and power cost aggregation unit 113. The arithmetic unit 213 includes, for example, a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The CPU reads the program code of the software that realizes each function according to this embodiment from ROM, loads it into RAM, and executes it. Variables and parameters that occur during the CPU's calculation processing are temporarily written to RAM, and these variables and parameters are read out by the CPU as appropriate.

[0037] The storage device 214 is responsible for storing data in the variable rate database 101, the fixed rate database 102, the variable equipment measurement database 105, the variable equipment specification database 106, and the non-variable equipment measurement database 111. The storage device 214 is composed of non-volatile storage such as an HDD (Hard Disk Drive), SSD (Solid State Drive), optical disk, magneto-optical disk, magnetic tape, or non-volatile memory. This non-volatile storage stores the OS (Operating System), various parameters, and programs necessary for the operation of the arithmetic unit 213. ROM and non-volatile storage store programs and data necessary for the CPU to operate. In other words, ROM and non-volatile storage are used as examples of non-transient storage media that are readable by a computer and store programs executed by the computer.

[0038] The customer system 22 includes an input / output device 221, a communication device 222, a variable device 103, a variable device measuring device 104, a non-variable device 109, and a non-variable device measuring device 110.

[0039] The communication device 222 transmits measurement data measured by the variable instrument measuring device 104 and the non-variable instrument measuring device 110 to the electricity rate design system 21. It also receives electricity rate design data from the electricity rate design system 21. The communication device 222 may be a NIC, for example. The communication device 222 can send and receive various types of data between devices via a LAN, the internet, a dedicated line, etc., connected to the terminals of the NIC.

[0040] The input / output device 221 is, for example, a PC (Personal Computer) or tablet terminal installed in the customer system 22, and is used to present the electricity rate design data received by the communication device 222 to the customer. The input / output device 221 may be, for example, a liquid crystal display monitor that displays processing results, etc., to the user of the customer system 22. Alternatively, the input / output device 221 may be, for example, a keyboard, mouse, etc., that allows the user of the customer system 22 to perform predetermined operations and give instructions.

[0041] Figure 3 is a schematic diagram showing the calculation process of the operating condition estimation unit 107 and the variable equipment operation plan calculation unit 108. Here, the variable equipment 103 is described as a storage-type hot water heat pump, which is an example of equipment that uses electricity to supply heating and cooling. The measurement data of the variable equipment 103, measured by the variable equipment measuring device 104 and stored in the variable equipment measurement database 105, includes the amount of electricity used, the amount of hot water stored, and the operating mode.

[0042] Graph 31 shows the change in hot water storage volume over time, with the horizontal axis representing time and the vertical axis representing the amount of hot water stored. Each bar in Graph 31 is called a time frame. To identify time frames, each bar is numbered 1, 2, 3, ... from left to right.

[0043] Period 311 represents the hot water storage operation mode, where hot water is stored by heating. During this period (in this example, from 0:00 to 6:00), heating continues. Over the 6 hours of period 311, water is added while simultaneously heating to reach the predetermined temperature. Period 312 is the hot water supply operation mode, where only hot water is supplied without heating. Therefore, the amount of stored hot water gradually decreases during period 312.

[0044] The variable equipment specification database 106 stores the hot water storage temperature as specification information (specification data). Generally, the tanks of hot water storage type heat pumps have high insulation properties, so for simplicity, we assume that heat loss due to natural heat dissipation can be ignored. Therefore, the heat demand Q(f) for hot water supply can be converted from the time change of the amount of hot water stored in the hot water supply operation mode using the following formula (1).

[0045] Q(f) = (V(f-1)-V(f))×(T-T0)×C …(1)

[0046] In equation (1), f is the time frame number of the time series data, Q(f) is the heat demand to be calculated, V(f) is the amount of hot water stored as measured by the variable instrument measuring device 104, T and T0 are the hot water storage temperature and tap water temperature as specification constants, and C is the specific heat of water as a physical constant. The right-hand side of equation (1) represents the amount of heat extracted from the hot water storage tank as the amount of hot water stored changes over time.

[0047] Graph 32 shows the heat demand converted using formula (1) to the amount of hot water stored. Graph 32 shows that heat demand occurs at the same time as the amount of hot water stored, as shown in Graph 31.

[0048] The operating condition estimation unit 107 estimates the heat demand for the variable equipment 103 as an operating condition based on the power consumption data and the specification data of the variable equipment 103. In the example of a hot water storage type heat pump, this heat demand is the operating condition that the operating condition estimation unit 107 should calculate. In Graph 32, the time axis is set to 24 hours, but the length of the time series of the measurement data may be one month, one year, etc. Furthermore, it is possible to convert the heat demand with greater accuracy by using the hot water storage temperature T as measurement data instead of the specification constant, or by using the water temperature T0 which changes seasonally as measurement data instead of the specification constant.

[0049] Furthermore, there are various types of storage-type hot water heat pumps, including models that can store and supply hot water simultaneously, and models in which the storage tank is of the circulating type and performs heat exchange with the water supply pipes to supply hot water. However, the methods for converting the heat demand for these types are publicly known and will not be specifically mentioned here. Moreover, the present invention does not limit the variable device 103 to a storage-type hot water heat pump, nor does it limit the storage-type hot water heat pump to just one type.

[0050] Next, we will explain how the Variable Equipment Operation Plan Calculation Unit 108 calculates an operation plan for variable and fixed charges based on the operation conditions calculated by the Operation Condition Estimation Unit 107, and how it calculates electricity costs for variable and fixed charges. The Variable Equipment Operation Plan Calculation Unit 108 calculates an operation plan that minimizes the electricity costs of the variable equipment 103 under either variable or fixed charges, with the constraint that the heat demand is satisfied.

[0051] The operating plan and electricity costs are calculated by solving a mathematical programming problem defined by the following objective function (equation (2)) and constraints (equations (3) and (4)) using a solver. Here, we will explain how to calculate the operating plan and electricity costs by referring to equation (2) below.

[0052] min.Σ_f(Y(f)×w(f))…(2)

[0053] Equation (2) is the objective function, and Σ_f represents the sum over time frame f. Y(f) is a given kWh price stored in the variable price database 101 or the fixed price database 102. The kWh price is time-series data, but for fixed prices, it will be a constant value if monthly changing fuel cost adjustments and market price adjustments are not taken into account. In the example of a storage-type hot water heat pump, w(f) is the amount of electricity used per time frame for heating (kWh). Equation (2) means minimizing the sum of the products of the kWh price and the amount of electricity used, that is, minimizing the electricity cost of the variable equipment 103.

[0054] v(f) = v(f-1)+w(f)×E / ((T-T0)×C) …(3)

[0055] v(f-1)×(T-T0)×C ≧ Q(f) …(4)

[0056] Equations (3) and (4) are constraints. In equation (3), E is the heat pump efficiency. Equation (3) represents the time change in the amount of hot water stored v(f) associated with the heat output from the heat pump. Equation (4) represents the constraint that the amount of heat that can be extracted from the hot water storage tank does not fall below the heat demand calculated in equation (1), that is, that the hot water supply does not run out during the operation of the hot water storage type heat pump. In addition, there are other obvious constraints, such as upper and lower limits on the amount of hot water stored and upper and lower limits on the output of the heat pump.

[0057] Here, the hot water storage temperature T and water temperature T0 are treated as scalar constants, but they may be replaced with time-series constants based on measurement data, similar to the operating condition estimation unit 107. If the hot water storage temperature T and water temperature T0 are replaced with time-series constants, the operating conditions passed from the operating condition estimation unit 107 to the variable equipment operation plan calculation unit 108 include the measurement data obtained from the variable equipment measurement database 105. Alternatively, the hot water storage temperature T and water temperature T0 may be treated as statistical time-series constants. In that case, such statistical values ​​are stored in the variable equipment specification database 106 in advance.

[0058] Furthermore, the heat pump efficiency E is a constant that depends on ambient temperature and other factors, and may be listed as efficiency curve data in the catalog information for storage-type hot water heat pumps. For this reason, time-series constants calculated in advance based on this data and meteorological data may be stored in the variable equipment specification database 106 and used in equation (3). In this way, it is possible to improve the accuracy of the operation plan by replacing the scalar constants used in equations (3) and (4) with time-series constants.

[0059] When solving the mathematical programming problem explained by equations (2) to (4), if the kWh unit price is variable, a solution is calculated that satisfies the constraints on the amount of hot water stored in equations (3) and (4) while heating water during the time of day when the kWh unit price is as low as possible. Graphs 33 and 34 in Figure 3 show the calculated solution.

[0060] Graph 33 shows an example of variable rates per kWh, and Graph 34 shows an example of electricity consumption corresponding to the variable rates. The variable rates are stored in the variable rate database 101 mentioned above. In this example, the operation plan shows that hot water storage operation is performed at the maximum output of the heat pump during the time when the kWh rate is lowest, and the amount of hot water that cannot be stored by hot water storage operation alone is supplemented by hot water storage operation in the following time period. Furthermore, Graph 33 shows that the variable rates are lower during the daytime (around 10am) and higher during the evening (around 8pm). In recent years, due to the installation of many solar power generation systems, there is often a surplus of electricity during the daytime, so the kWh rate of the variable rate is lower during the daytime. However, in the evening, solar power generation is shut down all at once, but electricity demand is high. Therefore, it is necessary to operate thermal power plants, so the kWh rate of the variable rate is higher.

[0061] Graph 34 shows that when water heating is performed during the daytime (around 10am) when variable rates are lower, electricity consumption increases. Furthermore, since the daytime hours alone are insufficient to meet the heat demand shown in Graph 32, additional water heating is performed between 3pm and 4pm, further increasing electricity consumption.

[0062] In the case of a fixed rate, the timing of water heating is determined by the kWh price and does not have time dependence. However, if, for example, the hot water storage temperature T and heat pump efficiency E are treated as time-series constants as described above, a solution with minimal natural heat loss and high heat pump efficiency will be calculated. This solution is graphed in Graph 35 of Figure 3. In this example, the operation plan shows water heating performed during the time when the temperature is high and the heat pump efficiency is high. For example, with a fixed rate, by operating the heat pump during the time before the heat demand increases and during the time when the temperature is high (between 10am and 4pm), heat loss can be reduced.

[0063] In the example described above, all electricity is assumed to be used for heating. Graph 31 assumes, for example, that the hot water storage operation mode is fixed to heat water from 0:00 to 6:00 using a timer. Therefore, when expressed in terms of electricity consumption, the bar graph will be the same height as in Graph 35, with bars lined up from 0:00 to 6:00. On the other hand, in Graph 34, the heating timing is planned dynamically within the range that satisfies the heat demand, and the time period of the hot water storage operation mode changes.

[0064] Based on the above calculation method, the variable equipment operation plan calculation unit 108 calculates the operation plan and outputs the electricity cost calculated as the objective function.

[0065] The non-variable equipment power cost calculation unit 112 does not solve operation planning problems like the variable equipment operation plan calculation unit 108, but calculates power costs based on measurement data of the non-variable equipment 109 using the following formula (5).

[0066] Σ_f(Y(f)×W(f)) …(5)

[0067] Y(f) is a given kWh unit price stored in the variable rate database 101 or the fixed rate database 102, similar to equation (2). W(f) is the amount of electricity consumed by the variable equipment 109, stored in the variable equipment measurement database 111.

[0068] Furthermore, in the case of the variable equipment operation plan calculation unit 108, if the electricity rate applied to the variable equipment 103 from the beginning is a fixed rate, the calculation of the operation plan is omitted when calculating the electricity cost based on the fixed rate database 102. Then, the variable equipment operation plan calculation unit 108 may calculate the electricity cost in the same manner as formula (5) based on the amount of electricity used, which is the measurement data of the variable equipment 103.

[0069] Figure 4 is a table illustrating the aggregation of electricity costs by the electricity cost aggregation unit 113. In this table, each column represents the case where fixed charges and variable charges are applied to variable equipment 103, and each row represents the case where fixed charges and variable charges are applied to non-variable equipment 109.

[0070] Rate Plan 1 is an electricity rate design that applies a fixed rate to both variable equipment 103 and non-variable equipment 109. The electricity rate design of Rate Plan 1 corresponds to a form in which the customer enters into a fixed-rate supply contract on a point-of-reception basis. In Rate Plan 1, the customer's cost burden is the sum of the electricity cost calculated using formula (2) for the variable equipment operation plan calculation unit 108 with a fixed kWh unit price, and the electricity cost calculated using formula (5) for the non-variable equipment electricity cost calculation unit 112 with a fixed kWh unit price.

[0071] Rate Plan 2 is an electricity rate design that applies variable rates to both variable equipment 103 and non-variable equipment 109. The electricity rate design of Rate Plan 2 corresponds to a form in which the customer enters into a variable rate supply contract on a point-of-reception basis. In Rate Plan 2, the customer's cost burden is the sum of the electricity cost calculated using formula (2) for the variable equipment operation plan calculation unit 108, which uses a variable rate per kWh, and the electricity cost calculated using formula (5) for the non-variable equipment electricity cost calculation unit 112, which uses a variable rate per kWh.

[0072] Rate Plan 3 is an electricity rate design that applies a variable rate to variable equipment 103 and a fixed rate to non-variable equipment 109. The electricity rate design of Rate Plan 3 corresponds to a form in which a consumer has different supply contracts depending on the electrical equipment downstream from the point of power reception. In Rate Plan 3, the consumer's cost burden is the sum of the electricity cost calculated using formula (2) for the variable equipment operation plan calculation unit 108, which uses a variable rate per kWh, and the electricity cost calculated using formula (5) for the non-variable equipment electricity cost calculation unit 112, which uses a fixed rate per kWh.

[0073] Rate Plan 4 is an electricity rate design that applies a fixed rate to variable equipment 103 and a variable rate to non-variable equipment 109. The electricity rate design of Rate Plan 4 corresponds to a situation where the consumer has different supply contracts depending on the electrical equipment downstream from the point of power reception, and the application of variable and fixed rates is reversed compared to Rate Plan 3. In Rate Plan 4, the consumer's cost burden is the sum of the electricity cost calculated using formula (2) for the variable equipment operation plan calculation unit 108 with a fixed kWh unit price, and the electricity cost calculated using formula (5) for the non-variable equipment electricity cost calculation unit 112 with a variable kWh unit price.

[0074] Figure 5 shows an example of a display that visualizes the electricity costs aggregated by the electricity cost aggregation unit 113. The input / output device 211 or input / output device 221 visualizes the electricity costs aggregated by the electricity cost aggregation unit 113, allowing retail electricity providers or consumers to check their electricity costs.

[0075] The bar graphs shown in Figure 5 represent rate plans 1, 2, and 3 from left to right. For each of rate plans 1, 2, and 3, areas 51, 53, and 55 represent the electricity costs related to variable equipment 103, while areas 52, 54, and 56 represent the electricity costs related to non-variable equipment 109. Note that the bar graphs shown from Figure 5 onward do not represent hourly electricity costs as shown in Figure 3, but rather the combined electricity costs of variable equipment 103 and non-variable equipment 109 on a monthly or yearly basis.

[0076] Comparing pricing plan 1 and pricing plan 2, the change from a fixed rate to a variable rate reduces the electricity costs of variable equipment 103, but the electricity costs of non-variable equipment 109 actually increase. This is the trade-off regarding the electricity costs of variable equipment 103 and non-variable equipment 109 that was explained in the challenges of the conventional technology.

[0077] On the other hand, we compare rate plans 1 and 2 with rate plan 3. In this case, regarding the power cost reduction effect of variable equipment 103, the power cost in rate plan 2 is the same as in rate plan 3. Furthermore, in rate plan 3, the power cost of the non-variable equipment 109 can be made the same as that of the non-variable equipment 109 in rate plan 1 without the side effect of increasing the power cost of the non-variable equipment 109. As a result, it can be seen that rate plan 3 has a greater total cost reduction effect than rate plans 1 and 2.

[0078] By looking at the bar graph shown in Figure 5, consumers can quantitatively confirm that there is indeed a cost-saving effect from an electricity rate design that distinguishes between variable equipment 103 and non-variable equipment 109 and applies variable rates only to variable equipment 103. Furthermore, quantitative confirmation enables agreement on electricity rate design between retail electricity providers and consumers. For example, a retail electricity provider can recommend rate plan 3 to a consumer.

[0079] Figure 6 illustrates rate plans 1 and 2 in the same manner as Figure 5. Areas 61 and 63 represent the electricity costs related to variable equipment 103, and areas 62 and 64 represent the electricity costs related to non-variable equipment 109.

[0080] The difference between the bar graph in Figure 6 and the bar graph in Figure 5 is that the application of variable pricing has increased the electricity costs of both the variable equipment 103 and the non-variable equipment 109. This corresponds to a situation where, due to operational constraints on the variable equipment 103, a demand shift from high-price kWh periods to low-price periods cannot be implemented.

[0081] For consumers, even if the electricity rate design limits the application of variable rates to variable equipment 103, there is no benefit in changing from a fixed rate to a variable rate. In other words, in this case, an agreement is reached between the retail electricity provider and the consumer that variable rates will not be applied to either variable equipment 103 or non-variable equipment 109.

[0082] Figure 7 illustrates rate plans 1, 2, and 4 in the same manner as Figure 5. Areas 71, 73, and 75 represent the electricity costs related to variable equipment 103, while areas 72, 74, and 76 represent the electricity costs related to non-variable equipment 109.

[0083] The difference between the bar graph in Figure 7 and the bar graph in Figure 5 is that the application of variable pricing has increased the electricity costs of variable equipment 103, while conversely, it has decreased the electricity costs of non-variable equipment 109. This indicates that the operational constraints on variable equipment 103 prevent a demand shift from high-price kWh periods to low-price periods.

[0084] On the other hand, the non-variable equipment 109 initially consumed a large amount of electricity during the low-price period and a small amount during the high-price period, which corresponds to a situation suitable for variable pricing. In this case, the retail electricity provider and the consumer reach an agreement, contrary to the example in Figure 5, to distinguish between the variable equipment 103 and the non-variable equipment 109 and to apply the variable pricing only to the non-variable equipment 109, as in pricing plan 4.

[0085] Furthermore, in the case shown in Figure 7, the expectation of cost reduction related to the combination of variable equipment 103 and variable charges is not always met. Through the calculation of electricity costs by the operating condition estimation unit 107 and the variable equipment operation plan calculation unit 108, it is possible to show consumers that the opposite situation can also occur. This has the effect of prompting consumers to make quantitative judgments.

[0086] One of the advantages of the electricity rate design system 21 according to this embodiment is that it can avoid the trade-offs that may arise from the uniform application of variable rates by distinguishing between variable equipment 103 and non-variable equipment 109 and applying variable or fixed rates to each. Furthermore, the electricity rate design system 21 can present the variable rate after application in a way that allows consumers to quantitatively judge whether or not there is a benefit to applying variable rates, depending on the operating constraints of the variable equipment 103. By presenting information to consumers, the electricity rate design system 21 also has the effect of supporting the formation of agreements regarding electricity rate design between retail electricity providers and consumers.

[0087] Figure 8 illustrates, using a time-series graph, a situation where a trade-off occurs between variable equipment 103 and non-variable equipment 109, as shown in rate plan 2 in Figure 5. Graph 81 shows the kWh unit price for variable rates. Graph 82 shows the amount of electricity used by variable equipment 103, and graph 83 shows the amount of electricity used by non-variable equipment 109. Graph 82 shows the amount of electricity used before the demand shift 821 and the amount of electricity used after the demand shift 822. In the example shown in Figure 8, a demand shift has been achieved for variable equipment 103 from a high-price period to a low-price period. In other words, due to the demand shift, the amount of electricity actually used by variable equipment 103 is only the amount of electricity used 822.

[0088] On the other hand, for the non-variable equipment 109, the amount of electricity used during off-peak hours is low, and the amount of electricity used during peak hours is high, so applying variable rates will increase electricity costs compared to fixed rates. For example, consider a situation where a restaurant that opens in the evening is subject to daytime discount electricity rates. In this situation, although the hot water storage heat pump can store hot water in advance during the day, the majority of the store's electricity consumption occurs during business hours, so it is clear that applying variable rates uniformly is not beneficial to the customer. In such cases, it is more beneficial for the customer to limit the application of variable rates to the variable equipment 103, as in rate plan 3.

[0089] The functional block diagram shown in Figure 1 illustrates a configuration in which power costs are passed from the variable equipment operation plan calculation unit 108 and the non-variable equipment power cost calculation unit 112 to the power cost aggregation unit 113. In addition to this configuration, power consumption data based on the operation plan or measured power consumption data may be passed, and a time-series graph as shown in Figure 8 may be presented to the customer as an explanation to supplement the graph in Figure 5. This presentation allows the customer to more concretely understand the issues related to rate plan 2 and the effects related to rate plan 3.

[0090] Figure 9 is a flowchart illustrating the process of supporting consensus building between retail electricity providers and consumers, following the functional configuration shown in Figure 1.

[0091] S901 is the operation condition estimation process of the variable device 103 by the operation condition estimation unit 107.

[0092] S902 is the process by the Variable Equipment Operation Plan Calculation Unit 108 to calculate the operation plan for the variable equipment 103. The Variable Equipment Operation Plan Calculation Unit 108 calculates the operation plan for the variable equipment 103 based on the operating conditions and calculates the power cost of the variable equipment 103 based on the operation plan.

[0093] S903 is the power cost calculation process for the variable equipment 109 performed by the variable equipment power cost calculation unit 112.

[0094] S904 is the process by which the power cost aggregation unit 113 aggregates the power costs of the variable equipment 103 calculated by the variable equipment operation plan calculation unit 108, and aggregates the power costs of the non-variable equipment 109 calculated by the non-variable equipment power cost calculation unit 112.

[0095] S905 is a process in which the power cost aggregation unit 113 compares rate plan 2, as explained using Figure 4, with rate plan 1 (see, for example, Figure 5). As a result of this comparison process, in the evaluation of conditional branch S906, it is determined whether or not the power cost of the non-variable equipment 109 has decreased in rate plan 2 compared to rate plan 1. If the power cost of the non-variable equipment 109 has decreased (Yes in S906), the power cost aggregation unit 113 then evaluates conditional branch S907. If the power cost of the non-variable equipment 109 has not decreased (No in S906), the power cost aggregation unit 113 then evaluates conditional branch S908.

[0096] In the evaluation of conditional branch S907, if the electricity cost of variable equipment 103 is lower in rate plan 2 compared to rate plan 1 (Yes in S907), then a uniform application of variable rates to variable equipment 103 and non-variable equipment 109 can be expected to result in cost savings compared to a uniform application of fixed rates. For this reason, the electricity cost aggregation unit 113 recommends rate plan 2 to the customer in S909.

[0097] In the evaluation of conditional branch S907, if the power cost of variable equipment 103 has not decreased (No. in S907), it corresponds to rate plan 2 shown in Figure 7. In this case, the power usage pattern of non-variable equipment 109 is suitable for variable rates from the beginning, but variable equipment 103 cannot implement a demand shift that takes advantage of variable rates due to operational constraints. For this reason, the power cost aggregation unit 113 recommends rate plan 4 to the customer in S910.

[0098] If the electricity cost of the non-variable equipment 109 has not decreased (No in S906), the electricity cost aggregation unit 113 evaluates the conditional branch S908. In the evaluation of the conditional branch S908, if the electricity cost of the variable equipment 103 has decreased in rate plan 2 compared to rate plan 1 (Yes in S908), then it corresponds to rate plan 2 shown in Figure 5. In this case, the cost reduction due to the application of variable rates to the variable equipment 103 is offset by the cost increase due to the application of variable rates to the non-variable equipment 109. For this reason, the electricity cost aggregation unit 113 recommends rate plan 3, which is effective in resolving the trade-off between the two, to the customer in S911.

[0099] In the evaluation of conditional branch S908, if the power cost of the variable equipment 103 has not decreased in rate plan 2 compared to rate plan 1 (No. in S908), it corresponds to rate plan 2 as shown in Figure 6. In this case, the variable equipment 103 cannot implement demand shifting that takes advantage of variable rates due to operational constraints. For this reason, the power cost aggregation unit 113 recommends rate plan 1, which uniformly applies a fixed rate, to the customer in S912.

[0100] Figure 10 shows an example of a data table for electricity rate design data. The data table for electricity rate design data is transmitted from the electricity rate design system 21 to the customer system 22 in the block diagram shown in Figure 2. The electricity cost aggregation unit 113 lists the electricity costs of variable equipment 103 to which the variable equipment operation plan calculation unit 108 has applied variable or fixed rates, and the electricity costs of non-variable equipment 109 to which the non-variable equipment electricity cost calculation unit 112 has applied variable or fixed rates, and presents them to the customer in the data table shown in Figure 10.

[0101] The data table shown in Figure 10 stores the rates applied to the variable equipment 103 and the non-variable equipment 109 for each of the rate plans 1 to 4 shown in Figure 4, as well as the amount of electricity costs calculated by the variable equipment operation plan calculation unit 108 and the non-variable equipment power cost calculation unit 112 corresponding to the applied rates. It also stores whether the plan is recommended or not to the customer, depending on the amount of electricity costs. In this example, rate plan 3, which applies a variable rate to the variable equipment 103 and a fixed rate to the non-variable equipment 109, has the lowest total cost, so this plan is recommended. The plan that the power cost aggregation unit 113 recommends to the customer is a combination of variable and fixed rates that results in lower electricity costs for both the variable equipment 103 and the non-variable equipment 109, respectively.

[0102] It should be noted that the presentation of fixed and variable kWh unit prices from retail electricity providers to consumers is self-evident and not limited to this embodiment, so it is omitted here. Furthermore, the operation of the variable equipment 103 can be carried out, for example, by solving a mathematical programming problem similar to that of the variable equipment operation plan calculation unit 108 each day to calculate an operation plan, and then setting that operation plan to the variable equipment 103. However, since such a method is a well-known technique, it is omitted here.

[0103] In the above explanation, the measured values ​​of the variable equipment 103 and the non-variable equipment 109 are assumed to be historical performance data. However, the data input to the operating condition estimation unit 107 and the non-variable equipment power cost calculation unit 112 may be, for example, time-series data of predicted values ​​based on the measured values ​​of the measurement data. Such prediction of time-series data can be performed using known techniques such as machine learning.

[0104] [effect] As described above, the electricity rate design system 21 estimates the operating conditions in the operating condition estimation unit 107 based on measurement data acquired from the customer's variable equipment 103. Then, the electricity rate design system 21 calculates an operating plan and electricity costs based on the operating conditions in the variable equipment operating plan calculation unit 108 by referring to the kWh unit price stored in the variable rate database 101 or the fixed rate database 102. In addition, the electricity rate design system 21 calculates electricity costs based on the measurement data acquired from the customer's non-variable equipment 109 by referring to the kWh unit price in the non-variable equipment electricity cost calculation unit 112. These electricity costs are aggregated in the electricity cost aggregation unit 113, and by comparing combinations of fixed and variable rates in a way that allows the customer to judge the effect of electricity cost reduction, it is possible to support agreement between retail electricity providers and customers regarding the design of electricity rates.

[0105] Traditionally, even with EVs, there are variable devices whose charging and discharging timings are limited, similar to commercial vehicles. Furthermore, traditionally, there were variable devices such as storage-type water heaters and thermal storage air conditioning systems that were subject to operational constraints stemming from heat demand. In such cases, it was not obvious whether applying variable pricing would lead to electricity cost reductions. This meant that consumers could not decide whether to adopt variable pricing, and retail electricity providers could not propose variable pricing to consumers with solid justification. Additionally, in services using specific meters (such as EV chargers), a system is used where variable pricing is applied to EV chargers among the consumer's electrical equipment, while fixed pricing is applied to other electrical equipment. On the other hand, the electricity rate design system 21 according to this embodiment can propose variable pricing with solid justification, enabling agreement on electricity rate design between retail electricity providers and consumers.

[0106] <Second Embodiment> Next, an example of the configuration and operation of the electricity rate design system according to the second embodiment of the present invention will be described with reference to Figures 11 to 18. Figure 11 is a block diagram showing an example of the functional configuration of the electricity rate design system 21A according to a second embodiment of the present invention.

[0107] Of the functional configurations of the electricity rate design system 21A, the variable rate database 101 to the non-variable equipment power cost calculation unit 112 are the same as the functional configuration example of the electricity rate design system 21 according to the first embodiment shown in Figure 1. The difference between Figure 11 and Figure 1 is that the electricity rate design system 21A includes a power cost aggregation unit 113A instead of the power cost aggregation unit 113, and also includes an aggregation constant database 1101 and a gain allocation adjustment support unit 1102.

[0108] The power cost aggregation unit 113A calculates the market risk management unit price using the method described below and reflects it in the aggregation of power costs. Here, the market risk management unit price is the unit price for the cost of preparing for fluctuations in the procurement unit price in the wholesale power trading market (hereinafter referred to as market risk). For example, it is a margin that is included in the kWh unit price charged to consumers in advance so that retail electricity businesses do not suffer losses even if the procurement unit price in the market rises.

[0109] The power cost aggregation unit 113A calculates a market risk management cost to prepare for fluctuations in procurement prices by subtracting at least one of the following from the power costs under the operation plan of the variable equipment 103 to which the variable rate has been applied by the variable equipment operation plan calculation unit 108: procurement costs, transmission costs, supply and demand management costs, and profits, which are calculated by multiplying the power consumption data under the operation plan by a constant stored in the aggregation constant database 1101. The power cost aggregation unit 113A then calculates the market risk management cost as the market risk management unit price by dividing the market risk management cost by the total value of the power consumption data and converting it to an amount per kWh of electricity.

[0110] The aggregated constant database 1101 stores constants as aggregated constants, which are time-series data or scalar data that include at least one of the following per kWh of electricity related to retail sales: procurement unit price, transmission unit price, supply and demand management unit price, and profit unit price. The aggregated constants are used in the calculation process of the electricity cost aggregation unit 113A. In the electricity cost aggregation unit 113A, in order to adjust variable charges as part of the aggregation process, it refers to aggregated constants such as the commission unit price (also called the minimum commission unit price), which does not include the procurement unit price, transmission unit price, or market risk management unit price.

[0111] The gain distribution adjustment support unit 1102 visualizes and supports the consensus-building process, which includes not only the retail electricity provider and the consumer, but also the equipment provider responsible for the leasing, operation, or maintenance of the variable equipment 103, using the method described later as shown in Figure 18. This support process is presented to the retail electricity provider via the input / output device 211 and to the consumer via the input / output device 221, similar to the first embodiment. For the equipment provider, in managing the variable equipment 103 shown in Figure 2, they may share the input / output device 221 with the consumer, or they may use a separate input / output device similar to the input / output device 221, although this is not shown in Figure 2.

[0112] Figure 12 illustrates the concept of market risk management unit price. Generally, the average kWh price of electricity supplied by a retail electricity provider to a consumer is broken down into the average procurement price 1201, the transmission price 1202 (payment to the transmission and distribution company), and the commission price 1203. The average procurement price 1201 is the price required to procure electricity and is calculated by weighting publicly available time-series data of procurement prices with electricity usage data under the operating plan of the variable equipment 103. The transmission price 1202 is the price paid to the transmission and distribution company and is publicly available. The commission price 1203 is the retail electricity provider's gross profit (hereinafter referred to as profit) plus supply and demand management costs required to maintain the planned simultaneous supply and demand, converted into an amount per kWh. The market risk management price 1204 is a value set considering the market risk when the retail electricity provider procures electricity. The commission price 1203 includes the market risk management price 1204. However, the market risk management unit price of 1204 is generally not expressed in a quantifiable form. Note that the unit price values ​​shown in Figure 12 and Figure 13 (described later) are hypothetical values ​​and not actual values.

[0113] The power cost aggregation unit 113A separates and quantifies the market risk management unit price 1204 from the commission unit price 1203. The power cost aggregation unit 113A calculates the market risk management unit price R for a predetermined period, such as one year, using the following formula (6).

[0114] R = Σ_f(Y(f)×w(f)) / Σ_f(w(f)) - Σ_f((P1(f)+P2+P3)×w(f)) / Σ_f(w(f)) …(6)

[0115] Regarding equation (6), the numerator of the first term on the right-hand side is the same as that of equation (2), which is the objective function of the variable equipment operation plan calculation unit 108. The numerator of this first term on the right-hand side is the electricity cost paid by the consumer for the variable equipment 103 over a predetermined period, and from the perspective of the retail electricity provider, it corresponds to sales. In the first term on the right-hand side, sales are divided by the total amount of electricity used over the predetermined period to convert it to sales per kWh.

[0116] In the numerator of the second term on the right-hand side, P1(f) is time-series data of the procurement unit price, for example, the actual value of the contract price in the market one day prior. P2 is the transmission unit price of 1202, which is often set by the transmission and distribution company as a constant value independent of time, but under a nodal price system, for example, it becomes time-series data that fluctuates over time. P3 is the commission unit price excluding the market risk management unit price, and the input / output device 211 sets the minimum amount necessary to secure, assuming the profit unit price per kWh and the supply and demand management unit price.

[0117] In equation (6), P1 to P3 are constants stored in the aggregated constant database 1101. Multiplying P1 to P3 by the amount of electricity used by the variable equipment 103, w(f), calculated by the variable equipment operation plan calculation unit 108, results in the sum of the retail electricity provider's procurement costs, transmission costs, supply and demand management costs, and the retail electricity provider's profit over a predetermined period. The second term on the right side divides the total amount by the total amount of electricity used over the predetermined period to convert it into an amount that combines the cost and profit per kWh. By subtracting the second term on the right side from the first term on the right side calculated in this way, the market risk management unit price R is calculated as the difference. Therefore, the variable equipment operation plan calculation unit 108 calculates the difference between the amount obtained by multiplying the amount of electricity used data when a fixed charge or a variable charge is applied by the procurement unit price stored in the aggregated constant database 1101, respectively, as the amount of reduction in procurement costs achieved by a demand shift based on a variable charge.

[0118] In the above explanation, P1(f) is expressed as the procurement unit price in formula (6), and in Figure 12, it is shown as the average procurement unit price of 1201 in the graph. The reason for this is to distinguish that P1(f) expressed in formula (6) is a time-varying parameter, while the average procurement unit price of 1201 shown in Figure 12 is a weighted average of P1(f) by the amount of electricity used w(f). Expressing the average procurement unit price of 1201 using the symbols of formula (6), it is shown as follows in formula (7).

[0119] Average procurement unit price = Σ_f(P1(f)×w(f)) / Σ_f(w(f)) …(7)

[0120] Thus, it is shown that the average procurement cost 1201 depends not only on the procurement cost P1(f) but also on the time variation of the amount of electricity used w(f). For this reason, in this embodiment, the power cost aggregation unit 113A calculates the market risk management cost by referring to the calculation results of the operating condition estimation unit 107 and the variable equipment operation plan calculation unit 108.

[0121] The fact that the average procurement cost depends on both the procurement cost and the amount of electricity used means that, from the perspective of a retail electricity provider, the factors influencing procurement costs exist on both the market and the consumer side. On the other hand, if a market-linked rate is applied to the variable device 103 as a variable rate, the retail electricity provider does not need to manage market risk for the amount of electricity used by the variable device 103. Therefore, there is no need to include the market risk management rate 1204 in the commission rate 1203. Also, from the consumer's perspective, since the amount of electricity used is a factor they can manage themselves, the factors influencing electricity costs are limited to the market.

[0122] Therefore, in this embodiment, market risk management is entrusted from the retail electricity provider to the consumer in the form of market-linked pricing, and a variable price is presented to the consumer after deducting the market risk management unit price. This example will be explained with reference to Figure 13.

[0123] Figure 13 shows an example of a variable price presented to a customer. As shown in Figure 13, the market-linked fee unit price 1301 is determined by subtracting the market risk management unit price 1204 calculated using formula (6) from the fee unit price 1203, and the variable rate kWh unit price is adjusted accordingly. Figures 12 and 13 were schematic diagrams showing the average value of the kWh unit price without showing the change in the variable rate over time. However, when the difference between the two kWh unit prices is illustrated, including the change in the variable rate over time, the graph shown in Figure 14 is obtained.

[0124] Figure 14 is a graph showing the time fluctuations of the kWh unit price. In Figure 14, the unadjusted variable rate 1401 is the original variable rate stored in the variable rate database 101. The unadjusted variable rate 1401 includes the commission unit price 1203. Furthermore, a portion of the commission unit price 1203 corresponds to the market risk management unit price 1204 calculated using formula (6).

[0125] The electricity cost aggregation unit 113A, when the variable rate is a market-linked rate, makes an adjustment by subtracting the market risk management unit price from the variable rate and presents the adjusted variable rate to the customer. For example, if the variable rate is a market-linked rate, the electricity cost aggregation unit 113A changes the commission unit price 1203 to the market-linked commission unit price 1301. Then, the electricity cost aggregation unit 113A can present the adjusted variable rate 1402 to the customer, which is the variable rate that includes the market-linked commission unit price 1301 and the market risk management unit price 1204 (the variable rate before adjustment 1401). At this time, the electricity costs shown in Figures 5 to 7 can also be visualized after making a similar adjustment (reduction of the market risk management unit price 1204).

[0126] Figure 15 shows an example of adjusted electricity costs. For example, taking Figure 5 as an example, the regions (electricity costs) 51, 53, and 55 related to the variable equipment 103 are adjusted to electricity costs 1501, 1502, and 1503 in Figure 15, respectively. These electricity costs were initially calculated by minimizing equation (2), but the adjusted electricity costs are calculated using the following equation (8).

[0127] Σ_f((Y(f)-R)×w(f)) …(8)

[0128] In equation (8), R is the market risk management unit price calculated in equation (6). (Y(f)-R) is the adjusted variable charge 1402 explained in Figure 14. w(f) is the amount of electricity used. The market risk management unit price R is a value set by retail electricity providers to hedge risks when procuring electricity. If the variable charge is a market-linked charge, the retail electricity provider charges the customer the market-linked charge as is when providing electricity purchased at the market-linked charge. In this case, the retail electricity provider does not need to take the market risk management unit price R. For this reason, the electricity cost aggregation unit 113A can reduce the commission unit price 1203 and adjust the electricity costs 1501, 1502, and 1503 for each rate plan.

[0129] As described above, the power cost aggregation unit 113A calculates the market risk management unit price in addition to the processing performed by the power cost aggregation unit 113. The power cost aggregation unit 113A also adjusts the variable charges stored in the variable charge database 101 based on the market risk management unit price. The power cost aggregation unit 113A then presents the adjusted variable charges and power costs to retail electricity providers and consumers through the visualization shown in Figure 14 or Figure 15.

[0130] In the second embodiment, the data table of electricity rate design data shown in Figure 10 is expanded as shown in Figure 16. Figure 16 shows an example of a data table for expanded electricity rate design data. The amounts in parentheses in this data table represent the adjusted electricity costs calculated using formula (8).

[0131] The power cost aggregation unit 113A adjusts the power cost of the variable equipment 103 calculated by the variable equipment operation plan calculation unit 108 by subtracting the market risk management cost, and presents the adjusted power cost to the customer. For example, in rate plan 2, when a variable rate is applied to the variable equipment 103, the adjusted power cost is 17,000 yen, which is shown in parentheses. The data table of the expanded power rate design data is sent to the customer, and the customer can check the expanded power rate.

[0132] Figure 17 shows an example of a data table that stores variable charges before and after adjustment.

[0133] Market-linked rates are constantly fluctuating rates that also change from day to day, but the data table shown in Figure 17 is an example of the fluctuating rates before and after adjustment for a given day. This data table uses a market risk management unit price of 3 yen / kWh to illustrate the fluctuating rates before and after adjustment. This data table may also be sent to customers so that they can check the rates hour by hour.

[0134] In the above explanation, the example given was that the variable charge applies to the variable equipment 103. However, as described in the first embodiment, the variable charge may also apply to the non-variable equipment 109. In that case, by replacing the amount of electricity used w(f) calculated for the variable equipment 103 with the amount of electricity used W(f) measured for the non-variable equipment 109 in formulas (6) to (8), the effect of reducing electricity costs by applying market-linked charges and excluding market risk management unit prices can be calculated in the same way.

[0135] Furthermore, the breakdown of the kWh unit price of electricity includes, in addition to the aforementioned procurement unit price, transmission unit price, supply and demand management unit price, and profit unit price, consumption tax and renewable energy surcharges may also be included, as well as discounts such as subsidies. Although not explicitly stated here, consumption tax, renewable energy surcharges, and subsidies can be treated similarly to transmission unit prices and reflected in the calculation of market risk management unit prices.

[0136] In the present invention, the first embodiment describes a method for determining whether to apply variable and fixed rates when differentiating between electrical equipment downstream of the power receiving point and applying variable and fixed rates, by evaluating the effect of reducing electricity costs through demand shifting. Furthermore, the description so far has shown that in the first embodiment, when market-linked rates are applied as variable rates, the retail electricity provider can further reduce electricity costs for consumers by deducting the market risk management unit price from the kWh unit price.

[0137] In the following sections, we will consider equipment upgrade costs, such as replacing existing non-variable equipment 109 with variable equipment 103, and position equipment providers who supply the variable equipment 103 as a third player, in addition to retail electricity providers and consumers. Then, we will explain how to support consensus building for distributing the gains obtained in the two-stage electricity cost reduction process among the players, as a visualization function of the gain distribution adjustment support unit 1102. Equipment providers are businesses that handle equipment leasing, operation, or maintenance, and are also called EaaS (Energy as A Service) providers.

[0138] Figure 18 is a triangular graph representing the profit distribution among retail electricity providers, consumers, and equipment providers. Here, profit refers to the costs that retail electricity providers can reduce when consumers adopt variable pricing and implement demand shifting. This reduces electricity costs for consumers and serves as a source of funds for investment recovery for equipment providers. The profit distribution shown in the triangular graph of Figure 18 is adjusted by the profit distribution adjustment support unit 1102 in Figure 11. The profit distribution adjustment support unit 1102 positions the reduction in procurement costs calculated by the variable equipment operation plan calculation unit 108 as the profit obtained through the cooperation of the retail electricity provider (selling electricity), the consumers (purchasing electricity), and the equipment provider (providing variable equipment 103 for a fee) as players, and visualizes the profit distributed to each player.

[0139] The triangular graph shown in Figure 18 utilizes the geometric property that the sum of the lengths of the perpendiculars drawn from any point inside an equilateral triangle to each side is equal to the height of the triangle. Here, the sum of the lengths of the perpendiculars corresponds to the total amount of gain, and the length of each perpendicular represents the gain allocated to the retail electricity provider, the consumer, and the equipment provider.

[0140] The height 1803 of the equilateral triangle 1801 represents the procurement cost reduction achieved when consumers perform a demand shift, as shown in the first embodiment, causing the timing of electricity procurement by retail electricity providers to shift from high-price periods to low-price periods in the market. This reduction in procurement cost is calculated using the procurement unit price P1(f) in formula (6) and the following formula (9).

[0141] Procurement cost reduction = Σ_f(P1(f)×w_fix(f))-Σ_f(P1(f)×w_var(f)) …(9)

[0142] In formula (9), w_fix(f) is the amount of electricity used by the variable equipment 103 calculated by applying a fixed charge in the variable equipment operation plan calculation unit 108, and w_var(f) is the amount of electricity used calculated by applying a variable charge. By multiplying the amount of electricity used calculated with a fixed charge and the amount of electricity used calculated with a variable charge by the procurement unit price P1(f), the first term calculates the procurement cost without demand shift, and the second term calculates the procurement cost with demand shift. Then, using formula (9), the difference between the first and second terms is calculated as the amount of reduction in procurement cost due to demand shift.

[0143] The difference 1804 between the height 1803 of equilateral triangle 1801 (white part) and the height of equilateral triangle 1802 (shaded part including the white part) represents the market risk management costs that retail electricity providers can reduce when consumers adopt market-linked pricing, as described in this embodiment. The market risk management costs are the value before converting formula (6) to an amount per kWh, and are expressed by the following formula (10) using the symbols of formula (6).

[0144] Market risk management cost = R × Σ_f(w(f)) …(10)

[0145] Next, we will explain the meaning of each perpendicular line and the meaning of the line segments obtained by dividing each perpendicular line. The line segment 1805 represents the profit allocated to retail electricity providers. The profit of retail electricity providers is adjusted, for example, by offsetting the variable rate shown in graph 33 of Figure 3. Using the symbol Y(f) for the kWh unit price shown in equation (2), the following equation (11) is obtained.

[0146] Y'(f) = Y(f) + ΔY …(11)

[0147] ΔY is the offset amount, and Y'(f) is the offset variable charge. A larger positive offset amount increases the retail electricity provider's profit, while a larger negative offset amount decreases it. Furthermore, using Y'(f) instead of Y(f) in equations (2) to (4) does not change the structure of the mathematical programming problem. Consequently, the demand shift operation plan also remains unchanged, and this offset adjustment does not alter the total profit, which is either a height of 1803 or a difference of 1804.

[0148] Line segment 1806 represents the gains allocated to consumers in a demand shift using variable rates. Line segment 1807 represents the gains allocated to consumers when market-linked rates are applied as variable rates. When market-linked rates are applied, consumers bear the market risk, so it is reasonable that the reduction in market risk management costs should be returned to consumers. This is represented in the construction of the triangular graph by making the length of line segment 1807 the same as the length of difference 1804. Furthermore, the gain allocation adjustment support unit 1102 positions the market risk management costs that become unnecessary for retail electricity providers when the variable rate is a market-linked rate as additional gains added to the gains, and allocates these additional gains to consumers who bear the risk of fluctuations in procurement unit prices.

[0149] Line segment 1808 represents the profit allocated to the equipment provider to cover the costs incurred in leasing, operating, or maintaining the variable equipment 103. Line segment 1809 represents the profit allocated to the equipment provider as their profit. For the equipment provider's business to be viable, a predetermined amount must be secured as line segment 1808, and line segment 1809 must be longer than zero. The profit allocated to the equipment provider is distributed as a payment from the customer to the equipment provider, and is therefore adjusted by the pricing agreement between the customer and the equipment provider.

[0150] Furthermore, if the equipment provider is not involved as a player and the customer installs the equipment themselves, the gains of line segments 1808 and 1809 also belong to the customer. Also, if the customer performs demand shifting using the variable equipment 103 that they already own and does not install any new equipment, the lengths of line segments 1808 and 1809 will be zero.

[0151] Thus, the second embodiment visualizes the distribution of gains using a triangular graph. This visualization helps to facilitate consensus building among the three parties regarding how to distribute the gains generated by the setting of variable rates by retail electricity providers, demand shifts by consumers, and the provision of variable equipment 103 by equipment providers, based on a quantitative common understanding and adjustment means.

[0152] In addition to the triangular graph shown on the left side of Figure 18, the gain allocation adjustment support unit 1102 can also represent the lengths of each perpendicular line in the triangular graph as three bar graphs, or divide a single bar graph into three parts. For example, the right side of Figure 18 shows an example where a single bar graph is divided into three parts. When converting the triangular graph to a bar graph, the overall height of the bar graph remains constant. In other words, the gain allocation adjustment support unit 1102 constructs the bar graph with an overall height equivalent to the height of the triangular graph. The bar graph for consumer gain consists of the demand shift portion and the market risk assumption portion. The equipment provider gain consists of the cost equivalent and the profit equivalent. Even with such bar graphs, the retail electricity provider gain, consumer gain, and equipment provider gain are clearly represented.

[0153] It should be noted that the present invention is not limited to the embodiments described above, and various other applications and modifications can be taken as long as they do not deviate from the gist of the present invention as described in the claims. For example, the embodiments described above are detailed and specific explanations of the configuration of the electricity rate design system in order to clearly explain the present invention, and are not necessarily limited to having all the configurations described. Furthermore, it is possible to replace some of the configurations of the embodiments described here with the configurations of other embodiments, and it is also possible to add the configurations of other embodiments to the configuration of one embodiment. In addition, it is possible to add, delete, or replace some of the configurations of each embodiment with other configurations. Furthermore, the control lines and information lines shown are those deemed necessary for explanatory purposes, and not all control lines and information lines are necessarily shown in the actual product. In reality, it is safe to assume that almost all components are interconnected. Furthermore, in each of the embodiments described above, when referring to the number of elements (including the number of elements, numerical values, quantities, ranges, etc.), unless specifically stated or clearly limited in principle to a particular number, the number is not limited to that particular number and may be greater than or less than that number. Furthermore, the system or apparatus in each of the embodiments described above may be a physical computer system (one or more physical computers) or a system built on a group of computing resources (multiple computing resources) such as a cloud infrastructure. The computer system or group of computing resources may include one or more interface devices (e.g., including communication devices and input / output devices), one or more storage devices (e.g., including memory (main memory) and auxiliary storage devices), and one or more arithmetic units.

[0154] Furthermore, in each of the embodiments described above, if the function is realized by the execution of a program by an arithmetic unit, the defined processing is carried out using a memory device and / or interface device as appropriate, so the function may be at least a part of one or more arithmetic units. The processing described with the function as the subject may also be processing performed by a system including one or more arithmetic units. Furthermore, in each of the embodiments described above, the program may be installed from the program source. The program source may be, for example, a program distribution computer or a computer-readable storage medium (e.g., a computer-readable non-transient storage medium). The descriptions of each function are examples, and multiple functions may be combined into one function, or one function may be divided into multiple functions.

[0155] 21...Electricity Rate Design System, 22...Customer, 101...Variable Rate Database, 102...Fixed Rate Database, 103...Variable Equipment, 104...Variable Equipment Measurement Device, 105...Variable Equipment Measurement Database, 106...Variable Equipment Specification Database, 107...Operating Condition Estimation Unit, 108...Variable Equipment Operation Plan Calculation Unit, 109...Non-Variable Equipment, 110...Non-Variable Equipment Measurement Device, 111...Non-Variable Equipment Measurement Database, 112...Non-Variable Equipment Power Cost Calculation Unit, 113...Power Cost Aggregation Unit, 211...Input / Output Device, 212...Communication Device, 213...Calculation Unit, 214...Memory Device

Claims

1. A variable rate database that stores variable rate electricity unit price data, A fixed-rate database that stores fixed-rate electricity unit price data, A variable equipment measurement database that stores variable equipment measurement data acquired from a variable equipment measurement device that measures the amount of energy used by customers' variable equipment, A variable device specification database storing the specification data of the aforementioned variable device, An operating condition estimation unit that estimates the operating conditions of the variable equipment based on the variable equipment measurement data and the variable equipment specification data, A variable equipment operation plan calculation unit calculates the operation plan and electricity costs of the variable equipment by applying the variable charge or the fixed charge under the aforementioned operating conditions, A variable equipment measurement database that stores variable equipment measurement data acquired from a variable equipment measurement device that measures the amount of energy used by the customer's variable equipment, A variable-variable equipment power cost calculation unit calculates the power cost of the variable equipment by applying the variable charge or the fixed charge to the variable equipment measurement data, The system includes a power cost aggregation unit that aggregates the power costs calculated by the variable equipment operation plan calculation unit and the power costs calculated by the non-variable equipment power cost calculation unit and presents the aggregated data to the customer as power rate design data. Electricity rate design system.

2. The power cost aggregation unit lists the power costs of the variable equipment to which the variable equipment operation plan calculation unit has applied the variable or fixed rates, and the power costs of the non-variable equipment to which the non-variable equipment power cost calculation unit has applied the variable or fixed rates, in a data table and presents them to the customer. The electricity rate design system according to claim 1.

3. The aforementioned variable device is a device that uses electricity to supply heating and cooling, The aforementioned variable device measurement data is power consumption data, The operating condition estimation unit estimates the heat demand for the variable equipment as an operating condition based on the power consumption data and the variable equipment specification data. The electricity rate design system according to claim 2.

4. The variable equipment operation plan calculation unit calculates an operation plan that minimizes the electricity costs of the variable equipment under the variable or fixed charges, with the constraint that the heat demand must be satisfied. The electricity rate design system according to claim 3.

5. The power cost aggregation unit presents the customer with a combination of the variable charge and the fixed charge that results in lower power costs for both the variable equipment and the non-variable equipment. The electricity rate design system according to claim 2.

6. The system includes an aggregated constant database that stores time-series data or scalar data constants, which include at least one of the following per kWh of electricity related to retail sales: procurement price, transmission price, supply and demand management price, and profit price. The power cost aggregation unit calculates, from the power costs under the operation plan of the variable equipment to which the variable charges have been applied by the variable equipment operation plan calculation unit, an amount obtained by subtracting at least one of the following from the power costs, which are calculated by multiplying the power consumption data under the operation plan by a constant stored in the aggregation constant database: procurement costs, transmission costs, supply and demand management costs, and profits, as market risk management costs to prepare for fluctuations in the procurement unit price. The market risk management cost is calculated by dividing the aforementioned market risk management cost by the total value of the aforementioned electricity usage data and converting it to an amount per kWh of electricity. The electricity rate design system according to claim 2.

7. The electricity cost aggregation unit, when the variable rate is a market-linked rate, makes an adjustment by subtracting the market risk management unit price from the variable rate, and presents the adjusted variable rate to the customer. The electricity rate design system according to claim 6.

8. The power cost aggregation unit adjusts the power cost of the variable equipment calculated by the variable equipment operation plan calculation unit by subtracting the market risk management cost, and presents the adjusted power cost to the customer. The electricity rate design system according to claim 6.

9. The variable equipment operation plan calculation unit calculates the difference between the amount obtained by multiplying the power consumption data when the fixed charge or the variable charge is applied by the procurement unit price stored in the aggregated constant database, respectively, as the amount of reduction in procurement costs achieved by the demand shift based on the variable charge. The system includes a profit distribution adjustment support unit that positions the reduction in procurement costs as a gain obtained through the cooperation of the retail electricity business operator that sells electricity, the consumer that purchases electricity, and the equipment provider that provides the variable equipment for a fee, and visualizes the gains allocated to each player. The electricity rate design system according to claim 6.

10. The profit distribution adjustment support unit, when the variable rate is a market-linked rate, positions the market risk management costs that are unnecessary for retail electricity providers as additional profits added to the profits, and distributes these additional profits to the consumers who assume the risk of fluctuations in the procurement unit price. The electricity rate design system according to claim 9.

11. A step of estimating the operating conditions of a variable device based on variable device measurement data of a customer's variable device stored in a variable device measurement database and specification data of the variable device stored in a variable device specification database. A step of calculating the operation plan and electricity costs of the variable equipment with the variable rate or fixed rate applied under the operating conditions, based on variable rate electricity unit price data stored in the variable rate database, fixed rate electricity unit price data stored in the fixed rate database, and specification data of the variable equipment. A step of calculating the electricity cost of the variable equipment by applying the variable charge or the fixed charge to the variable equipment measurement data of the customer's variable equipment stored in the variable equipment measurement database, The step includes presenting to the customer, as electricity rate design data, data that aggregates the electricity costs calculated for the variable equipment and the electricity costs calculated for the non-variable equipment. Electricity rate design methods.

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