Control method, power trading system, and program

Abstract

To provide a control method and the like capable of suppressing fraudulent electricity trading.SOLUTION: The control method includes: a step of receiving a piece of first transaction data including a piece of power transmission amount information and the like representing the amount of the power transmitted to a power storage facility from a first power facility (S104); a step of acquiring a piece of power reception information including a piece of received power amount information, etc. representing the amount of received power received from the first power facility from the power storage facility (S105, 106); a step of verifying the first transaction data by referring to the power reception information (S107); a step of executing a first consensus algorithm together with a second server (S110) when the verification of the first transaction data is successful (Y in S107); and a step of recording a block including the first transaction data on a distributed ledger of a first server when the validity of the first transaction data is verified by the first consensus algorithm.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present disclosure relates to a control method, and more particularly to a control method in a system for trading electricity generated in homes and the like. [Background technology]

[0002] In recent years, renewable energy sources such as solar power generation have become more widespread. With solar power generation, not only is the electricity generated at home used, but surplus electricity is also sold to power companies.

[0003] In the future, it is expected that electricity will be sold not only to power companies but also directly to nearby residents (see, for example, Non-Patent Document 1). Non-Patent Document 1 considers the application of blockchain technology to the electricity sector for person-to-person electricity transactions, building an autonomous decentralized system. For example, if a residential user with solar power generation wants to sell excess electricity to another user, they can use the blockchain to enter into a sales contract.

[0004] According to Non-Patent Document 1, if the home of a user who wants to sell excess electricity can store generated electricity, the stored electricity can be bought and sold directly to other users. In other words, peer-to-peer trading is possible without the intervention of an intermediary such as an electric power company. On the other hand, if the home of a user who wants to sell excess electricity cannot store generated electricity, peer-to-peer trading of electricity must be carried out through an intermediary that has electricity storage facilities. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Mizuho Industry Research, How Will Digital Innovation Transform Business? - Exploring Issues and Strategies from Notable Initiatives, Electricity - Prospects for an Electricity Sharing Economy Utilizing Blockchain Technology, Vol. 57, No. 1, 2017 (URL: https: / / www.mizuhobank.co.jp / corporate / bizinfo / industry / sangyou / m1057.html) Summary of the Invention [Problem to be solved by the invention]

[0006] However, when electricity trading between individuals is entrusted to an intermediary that has power storage facilities, the intermediary may purchase electricity at a price that is unfairly lower than the average desired purchase price, or may sell the purchased electricity at a unit price that is unfairly higher than the purchase price. In other words, when electricity trading between individuals is entrusted to an intermediary that has power storage facilities, electricity trading may be conducted through fraudulent intermediary transactions.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a control method and the like that can suppress fraudulent energy trading. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the control method disclosed herein is a control method executed by a server in an energy trading system including a second power equipment, a power storage equipment connected to the second power equipment, and a server with which the second power equipment and the power storage equipment can communicate via a network, the control method acquiring transaction data from the second power equipment including power purchase amount information indicating the amount of power to be purchased that is requested to be purchased, determining whether the distance between the second power equipment and the power storage equipment is within a predetermined range or whether the amount of loss of power transmitted from the power storage equipment to the second power equipment is within a predetermined range, and requesting the power storage equipment to transmit power to the second power equipment if it is determined that the distance between the second power equipment and the power storage equipment is within the predetermined range or if it is determined that the amount of loss of power transmitted from the power storage equipment to the second power equipment is within the predetermined range.

[0009] These comprehensive or specific aspects may be realized as a system, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM, or may be realized as any combination of a system, a method, an integrated circuit, a computer program, and a recording medium. [Effects of the Invention]

[0010] According to the control method and the like of the present disclosure, fraudulent electricity trading can be suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an example of an overall configuration of an energy trading system according to an embodiment. [Figure 2] 1 is a diagram illustrating an example of the overall configuration of a house according to an embodiment. [Figure 3] FIG. 3 is a block diagram showing the functional configuration of a controller shown in FIG. 2. [Figure 4] FIG. 10 is a diagram illustrating an example of an input screen for inputting power purchase request information according to the embodiment. [Figure 5] FIG. 2 is a block diagram showing a functional configuration of an authentication server according to an embodiment. [Figure 6A] FIG. 1 is an explanatory diagram showing the data structure of a blockchain. [Figure 6B] FIG. 2 is an explanatory diagram illustrating the data structure of transaction data. [Figure 7A] FIG. 4 is a diagram illustrating an example of a power storage list according to the embodiment. [Figure 7B] FIG. 4 is a diagram illustrating an example of a power purchase request list according to the embodiment. [Figure 8] FIG. 4 is a diagram illustrating an example of a power purchase list according to the embodiment. [Figure 9] FIG. 2 is a block diagram showing a functional configuration of a management server according to an embodiment. [Figure 10] FIG. 2 is an overall sequence diagram of power trading according to an embodiment. [Figure 11] FIG. 4 is a sequence diagram of a power selling process according to an embodiment. [Figure 12] FIG. 4 is a sequence diagram of a power purchasing process according to an embodiment. [Figure 13] FIG. 4 is a sequence diagram of a power purchasing process according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] A control method according to one embodiment of the present disclosure is a control method executed by a server in an energy trading system including a second power facility, a power storage facility connected to the second power facility, and a server with which the second power facility and the power storage facility can communicate via a network, the control method obtaining transaction data from the second power facility including power purchase amount information indicating the amount of power to be purchased, determining whether the distance between the second power facility and the power storage facility is within a predetermined range or whether the amount of loss of power transmitted from the power storage facility to the second power facility is within a predetermined range, and requesting the power storage facility to transmit power to the second power facility if it is determined that the distance between the second power facility and the power storage facility is within the predetermined range or if it is determined that the amount of loss of power transmitted from the power storage facility to the second power facility is within the predetermined range.

[0013] An energy trading system according to one embodiment of the present disclosure includes a second power facility, a power storage facility connected to the second power facility, and a server with which the second power facility and the power storage facility can communicate via a network, wherein the server acquires transaction data from the second power facility, including power purchase amount information indicating the amount of power to be purchased, determines whether the distance between the second power facility and the power storage facility is within a predetermined range, or whether an amount of loss of power to be transmitted from the power storage facility to the second power facility is within a predetermined range, and requests the power storage facility to transmit power to the second power facility if it is determined that the distance between the second power facility and the power storage facility is within the predetermined range, or if it is determined that the amount of loss of power to be transmitted from the power storage facility to the second power facility is within the predetermined range.

[0014] A program according to one embodiment of the present disclosure is a program for causing a computer to execute a control method in an energy trading system including a second power facility, a power storage facility connected to the second power facility, and a server with which the second power facility and the power storage facility can communicate via a network, the program causing a computer to execute the following: acquire transaction data from the second power facility, including power purchase amount information indicating the amount of power to be purchased that is requested to be purchased; determine whether the distance between the second power facility and the power storage facility is within a predetermined range, or whether the amount of loss of power transmitted from the power storage facility to the second power facility is within a predetermined range; and, if it is determined that the distance between the second power facility and the power storage facility is within the predetermined range, or if it is determined that the amount of loss of power transmitted from the power storage facility to the second power facility is within the predetermined range, request the power storage facility to transmit power to the second power facility.

[0015] A control method according to one embodiment of the present disclosure is a control method executed by a first server of a plurality of servers in an energy trading system including an electric power facility used by a user, an electric power storage facility, and a plurality of servers with which the electric power facility and the electric power storage facility can communicate via a network, the control method comprising: acquiring transaction data including electric power purchase amount information indicating the amount of electric power purchased that the user requests to purchase, and the user's electronic signature; acquiring electric power storage information including electric power storage amount information indicating the amount of stored electric power held by the electric power storage facility from the electric power storage facility; determining whether electric power can be transmitted from the electric power storage facility to the electric power facility based on the electric power purchase amount information and the electric power storage amount information using a smart contract; and, if the electric power transmission is possible, sending an electric power transmission request to the electric power storage facility.

[0016] The energy trading system includes an electric power facility used by a user, an energy storage facility, and a plurality of servers with which the electric power facility and the energy storage facility can communicate via a network, wherein a first server of the plurality of servers acquires transaction data including power purchase amount information indicating the amount of power purchased that the user requests to purchase and the user's electronic signature, acquires energy storage information including energy storage amount information indicating the amount of stored power held by the energy storage facility from the energy storage facility, determines whether or not electricity can be transmitted from the energy storage facility to the electric power facility based on the power purchase amount information and the energy storage amount information using a smart contract, and if the electricity transmission is possible, sends an electricity transmission request to the energy storage facility.

[0017] A control method according to one aspect of the present disclosure is a control method executed by a first server of a power trading system including a first power facility used by a first user, a power storage facility connected to the first power facility via a power line, and a plurality of servers with which the first power facility and the power storage facility can communicate via a network, the control method including the steps of receiving, from the first power facility via the network, power transmission amount information indicating an amount of power transmitted from the first power facility to the power storage facility via the power line and first transaction data including an electronic signature of the first user, acquiring, from the power storage facility via the network, power reception information including power reception amount information indicating an amount of power received by the power storage facility from the first power facility, and and if the verification of the first user's digital signature and the verification of the legitimacy of the first transaction data are successful in the step of verifying the first transaction data, transferring the first transaction data to a plurality of second servers different from the first server among the plurality of servers; executing a first consensus algorithm together with the second servers to reach an agreement on the legitimacy of the first transaction data; and if the legitimacy of the first transaction data is agreed upon by the first consensus algorithm, recording a block including the first transaction data in a distributed ledger of the first server.

[0018] In this way, transaction data for electricity transmitted to energy storage facilities is recorded on a distributed ledger. This makes the transaction data public and makes it possible to detect tampering, thereby preventing fraudulent energy transactions by service providers that own storage batteries.

[0019] In addition, the step of verifying the first transaction data may include a step of comparing the transmitted power amount information and the received power amount information, a step of verifying the electronic signature of the first user, and a step of verifying the legitimacy of the first transaction data.

[0020] This makes it possible to verify the consistency between the power transmitted to the power storage facility and the power received by the power storage facility, as well as the validity of the first transaction data, thereby enabling tampering detection.

[0021] In addition, the first transaction data may further include a first timestamp indicating a first date and time when the transmitted power was transmitted, and the received power information may further include a second timestamp indicating a second date and time when the received power was received, and the comparing step may further include comparing the first timestamp and the second timestamp.

[0022] Furthermore, the energy trading system may further include a second power facility used by a second user, the second power facility being connected to the power storage facility via the power line and capable of communicating with the plurality of servers via the network, and the control method may further include the steps of receiving, from the second power facility via the network, second transaction data including power purchase amount information indicating an amount of power purchase requested by the second user and a digital signature of the second user; verifying the received second transaction data; if, in the verifying of the second transaction data, the verification of the second user's digital signature and the verification of the legitimacy of the second transaction data are successful, transferring the second transaction data to the second server; executing, together with the second server, a second consensus algorithm for reaching an agreement on the legitimacy of the second transaction data; and, if the legitimacy of the second transaction data is agreed upon by the second consensus algorithm, recording a block including the second transaction data in the distributed ledger of the first server.

[0023] In this way, the second transaction data of the blockchain indicating the power purchase request is recorded in the distributed ledger. This makes the transaction data of the power transaction public and makes it possible to detect tampering, thereby preventing fraudulent power transactions by service providers that own storage batteries.

[0024] Furthermore, the control method may further include the steps of: acquiring, from the power storage equipment via the network, power storage information including power storage amount information indicating the amount of stored power held by the power storage equipment; comparing the power purchase amount information with the power storage amount information to determine whether power transmission from the power storage equipment to the second power equipment is possible; if power transmission from the power storage equipment to the second power equipment via the power line is possible, requesting the power storage equipment to transmit power to the second power equipment and generating third transaction data indicating an energy trading matching result to the effect that stored power will be transmitted from the power storage equipment to the second power equipment; transferring the third transaction data to the second server; executing, together with the second server, a third consensus algorithm for reaching an agreement on the validity of the third transaction data; and, if the validity of the third transaction data is agreed upon by the third consensus algorithm, recording a block including the third transaction data in a distributed ledger of the first server.

[0025] In this way, the third transaction data of the blockchain, which indicates the matching results of energy transactions via storage batteries, is recorded in the distributed ledger. This makes the transaction data of energy transactions public and makes it possible to detect tampering, thereby preventing fraudulent energy transactions by service providers that own storage batteries.

[0026] Furthermore, when requesting the energy storage facility to transmit electricity to the second power facility, the method may include the steps of: generating fourth transaction data indicating a matching result of the electricity transaction to the effect that the energy storage facility has been requested to transmit stored electricity to the second power facility; transferring the fourth transaction data to the second server; executing a fourth consensus algorithm together with the second server to reach an agreement on the legitimacy of the fourth transaction data; and, when the legitimacy of the fourth transaction data is agreed upon by the fourth consensus algorithm, recording a block including the fourth transaction data in the distributed ledger of the first server, wherein the third transaction data may further include information indicating that stored electricity has been transmitted from the energy storage facility to the second power facility.

[0027] The first power facility and the second power facility may include at least one of a solar power generation system, a gas power generation system, and a wind power generation system.

[0028] Furthermore, the step of executing the second consensus algorithm may include a step of receiving second reports from each of the second servers indicating whether the validation of the legitimacy of the second transaction data was successful or not, and a step of determining whether the number of the second reports exceeds a predetermined number, and a step of determining that, when the number of the second reports exceeds the predetermined number, the second consensus algorithm has reached an agreement on the legitimacy of the second transaction data.

[0029] Furthermore, the step of executing the first consensus algorithm may include the steps of receiving first reports from each of the second servers indicating whether verification of the legitimacy of the first transaction data has been successful, determining whether the number of the first reports exceeds a predetermined number, and determining, when the number of the first reports exceeds the predetermined number, that the first consensus algorithm has agreed upon and verified the legitimacy of the first transaction data.

[0030] Furthermore, after the step of recording a block including the first transaction data in the distributed ledger, the method may further include a step in which the first server pays an incentive to the first user and then notifies the first user that the incentive has been paid.

[0031] Furthermore, a controller according to one aspect of the present disclosure is a controller that controls a first power facility in an energy trading system including a first power facility used by a first user, a power storage facility connectable to the first power facility via a power line, and a plurality of servers with which the first power facility and the power storage facility can communicate via a network, the controller including a processor and a memory storing a program that causes the processor to execute predetermined processing, the predetermined processing including a step of determining whether or not an amount of surplus power of the first power facility is equal to or greater than a predetermined value, a step of transmitting at least a portion of the amount of surplus power to the power storage facility via a power line as transmission power, and a step of indicating the amount of the transmission power. The method includes the steps of generating first transaction data including information on the amount of transmitted power and the electronic signature of the first user, transmitting the first transaction data to a first server of the plurality of servers via the network, displaying compensation information on a display indicating compensation to be paid to the first user according to the amount of transmitted power if the authenticity of the first transaction data is verified by the plurality of servers and a block including the first transaction data is recorded in a distributed ledger of each of the plurality of servers, and displaying failure information indicating that the first transaction data was not verified on the display if the authenticity of the first transaction data is not verified by the plurality of servers.

[0032] Furthermore, a control method of a controller according to an aspect of the present disclosure is a control method of a display that displays information on energy trading of a first energy facility used by a first user, an energy storage facility connected to the first energy facility via a power line, and a plurality of servers with which the first energy facility and the energy storage facility can communicate via a network, the control method including the steps of: when an amount of surplus energy of the first energy facility is equal to or greater than a predetermined value, causing the display to display energy transmission information indicating that at least a portion of the amount of surplus energy has been transmitted to the energy storage facility via the power line as transmission energy; and displaying a first transaction information including transmission energy amount information indicating the amount of the transmission energy and an electronic signature of the first user. The method includes the steps of: displaying on the display verification in-progress information indicating that the legitimacy of the first transaction data is being verified, from the time data is transmitted to a first server among the plurality of servers until the legitimacy of the first transaction data is verified by the plurality of servers; displaying on the display compensation information indicating the compensation paid to the first user in accordance with the amount of transmitted power, when the legitimacy of the first transaction data is verified by the plurality of servers; and displaying on the display failure information indicating that agreement has not been reached, when the legitimacy of the first transaction data is not agreed upon by the plurality of servers.

[0033] Furthermore, a data structure according to one embodiment of the present disclosure is a data structure used for blocks recorded as a blockchain in an energy trading system including a first power facility used by a first user, a power storage facility connected to the first power facility via a power line, and a plurality of servers with which the first power facility and the power storage facility can communicate via a network, the data structure including: a blockchain address, which is an identifier included in a block of the blockchain and generated using the private key of the first user, for identifying at least one of the first user and the first power facility; transmitted power amount information indicating the amount of transmitted power transmitted by the first power facility to the power storage facility; and an electronic signature of the first user; and the transmitted power amount information is used to verify the legitimacy of the transaction related to the power transmission by being compared with purchased power amount information indicating the amount of received power received by the power storage facility from the first power facility.

[0034] An energy trading system according to one aspect of the present disclosure is an energy trading system including: a first power facility used by a first user; a power storage facility connected to the first power facility via a power line; and a plurality of servers communicatively connected to the first power facility and the power storage facility via a network, wherein a first controller included in the first power facility causes the power storage facility to transmit at least a portion of surplus energy of the first power facility as transmission energy via the power line, generates first transaction data including transmission energy amount information indicating an amount of the transmission energy and an electronic signature of the first user, and transmits the first transaction data to a first server among the plurality of servers via the network; a second controller included in the power storage facility generates power reception information including received energy amount information indicating an amount of received energy received by the power storage facility from the first power facility, and in a power receiving management list, the first server acquires the power receiving information from the power storage facility via the network, and verifies the first transaction data by referring to the power receiving information, and if verification of the first transaction data succeeds in verifying the electronic signature of the first user and the legitimacy of the first transaction data, transfers the first transaction data to a second server which is a second server among the plurality of servers different from the first server, the first server and the second server execute a first consensus algorithm on the first transaction data, and if the legitimacy of the first transaction data is verified by the first consensus algorithm, records a block including the first transaction data in a distributed ledger of the first server.

[0035] Hereinafter, embodiments will be described with reference to the drawings. Note that each of the embodiments described below represents a preferred specific example of the present disclosure. In other words, the numerical values, shapes, materials, components, component arrangements and connection forms, steps, and step orders shown in the following embodiments are merely examples and are not intended to limit the present disclosure. The present disclosure is defined based on the claims. Therefore, among the components in the following embodiments, components that are not recited in the independent claims that represent the superordinate concept of the present disclosure are not necessarily required to achieve the objectives of the present disclosure, but are described as components that constitute more preferred embodiments.

[0036] (Embodiment 1) First, the system configuration of the present disclosure will be described.

[0037] [1. System Configuration] The energy trading system disclosed herein curbs fraudulent energy trading by conducting energy trading using blockchain technology, such as recording transaction data of energy trading with service providers that own storage batteries as intermediaries in a distributed ledger.

[0038] Hereinafter, an energy trading system and the like according to an embodiment will be described with reference to the drawings.

[0039] [1.1 Overall Configuration of Energy Trading System 10] FIG. 1 is a diagram showing an example of the overall configuration of an energy trading system 10 according to the present embodiment.

[0040] As shown in Fig. 1, the energy trading system 10 includes, for example, houses 100a, 100b, and 100c, authentication servers 200a, 200b, and 200c, a storage battery 300, and a management server 350 that manages the storage battery 300. These are connected by a communication network 400. The houses 100a, 100b, and 100c and the storage battery 300 are also connected by a power network 500. The power network 500 is an example of a power line, and is a network that allows the exchange of power between houses. The power network 500 may be a dedicated line, or may utilize a power network installed by a power company.

[0041] Furthermore, authentication servers 200a, 200b, and 200c (hereinafter also referred to as authentication server 200a, etc.) are connected to storage devices 201a, 201b, and 201c. Authentication servers 200a, etc. may be connected to storage devices 201a, etc. via a communication network 400, or may include storage device 201a internally. Storage device 201a has a distributed ledger in which transaction data and blocks of the blockchain are electronically recorded.

[0042] 1 shows an example in which the energy trading system 10 includes three residences and three authentication servers, but the present invention is not limited to this. That is, the energy trading system 10 may include four or more residences and four or more authentication servers.

[0043] [1.2 Configuration of the house 100a] Since the houses 100b and 100c have the same configuration, the house 100a will be described below as an example.

[0044] FIG. 2 is a diagram showing an example of the overall configuration of a house 100a according to this embodiment.

[0045] 2, the home 100a includes a controller 101, a solar power generation unit 102, and a power meter 103. The controller 101, the solar power generation unit 102, and the power meter 103 are connected to a communication network 110. The solar power generation unit 102 and the power meter 103 are also connected to a power network 111, and the power meter 103 is connected to a power network 500 outside the home 100a.

[0046] Here, the residence 100a etc. is an example of a building having power equipment used by the first user or the second user, and is, for example, a house such as a residential building, but is not limited to this. The residence 100a etc. may also be a building such as a factory or office building. In other words, the residence 100a etc. can be of any type as long as it is a building having power equipment used by a user.

[0047] <Controller 101> The controller 101 is, for example, a controller of an energy management system, and is an example of a controller that controls the first power facility or the second power facility in the energy trading system 10.

[0048] In this embodiment, the controller 101 displays the solar power generation 102 and inputs applications for selling or purchasing power. The controller 101 also controls the solar power generation 102 and transmits power to the power network 111 or the power network 500. The controller 101 also manages the amount of transmitted power and notifies the authentication server 200a and the like. Details will be described later.

[0049] <Solar Power Generation 102> The solar power generation system 102 is an example of a solar power generation device included in the first power facility or the second power facility. The solar power generation system 102 is a device equipped with a power generation method that directly converts sunlight into electric power using solar cells. The solar power generation system 102 uses the generated electric power within the house 100a and transmits the generated electric power to the electric power network 500 via the electric power network 111.

[0050] The solar power generation system 102 is not limited to a solar power generation system, but may be a gas power generation system, a wind power generation system, or the like.

[0051] <Power meter 103> The power meter 103 is included in the first power facility or the second power facility, and measures the amount of power transmitted to or received from the power network 500. When the solar power generation unit 102 transmits power to the power network 500 in response to a power transmission instruction from the controller 101, the power meter 103 measures the time and amount of power transmitted and notifies the controller 101. In response to a power usage instruction from the controller 101, the power meter 103 measures the amount of power received from the power network 500 and used. Note that the power meter 103 may be included in the controller 101.

[0052] An example of the configuration of the controller 101 will be described below.

[0053] [1.3 Controller 101 Configuration] FIG. 3 is a block diagram showing the functional configuration of the controller 101 shown in FIG.

[0054] The controller 101 includes a processor and a memory that stores a program that causes the processor to execute a predetermined process. In other words, the controller 101 is realized by the processor executing the predetermined program using the memory. In this embodiment, the controller 101 includes an input unit 1011, a transaction data generation unit 1012, a control unit 1013, a recording unit 1014, and a communication unit 1015. Each component will be described below.

[0055] <Input section 1011> The input unit 1011 creates an input screen for the user to input information for a power sale request or a power purchase request. When the user inputs power sale request information or power purchase request information on the created input screen, the input unit 1011 transmits the input power sale request information or power purchase request information to the transaction data generation unit 1012.

[0056] FIG. 4 is a diagram showing an example of an input screen for inputting power purchase request information according to the present embodiment. For example, as shown in FIG. 4, on input screen 1011a for inputting power purchase request information, a user inputs a date, an amount of power to be sold, and a unit price of power to be purchased. Note that in the example shown in FIG. 4, the amount of power to be purchased is displayed in kWh, but this is not limiting. It may also be a percentage of power generated by photovoltaic power generation system 102. Furthermore, the amount of power to be sold and the unit price of power to be purchased do not have to be input by the user, but may be determined in advance by energy trading system 10. When a user sets a unit price of power to be purchased, it becomes possible to obtain power preferentially by paying a price higher than the market price. Note that the input unit 1011 may present the date, amount of power to be purchased, and unit price of power to be purchased provisionally input on input screen 1011a, and have the user input whether or not they agree, such as "yes" or "no."

[0057] <Transaction Data Generation Unit 1012> The transaction data generation unit 1012 generates transaction data in the blockchain based on the power sale request information or the power sale request information received from the input unit 1011. The transaction data generation unit 1012 may determine whether the amount of surplus power of the solar power generation unit 102 is equal to or greater than a predetermined value, and generate transaction data if the amount is equal to or greater than the predetermined value. Here, the predetermined value is, for example, the amount of power to be sold included in the power sale request information received from the input unit 1011 as the amount of surplus power.

[0058] The transaction data generated by the transaction data generation unit 1012 is an example of the first transaction data and the second transaction data.

[0059] The first transaction data includes power transmission amount information indicating the amount of power transmitted by the first power facility to the power storage facility via the power line and the electronic signature of the first user. The first transaction data further includes a first blockchain address, which is an identifier identifying at least one of the first user and the first power facility, and a first timestamp indicating the first date and time when the power was transmitted. It is not essential that the first transaction data include the first timestamp. There may be multiple first blockchain addresses, as long as they function as identifiers identifying at least one of the first user and the first power facility. It is sufficient to include one of the addresses in the first transaction data. The second transaction data includes power purchase amount information indicating the amount of power purchased that the second user requests to purchase, and the electronic signature of the second user. The second transaction data further includes a second blockchain address, which is an identifier identifying at least one of the second user and the second power facility. Similarly, there may be multiple types of second blockchain addresses as long as they function as identifiers that identify at least one of the second user and the second power facility. One of the types may be included in the second transaction data.

[0060] In this way, the transaction data generated by the transaction data generation unit 1012 includes the blockchain address of the user or the controller 101, the power sale request information or the power purchase request information, and the user's signature.

[0061] The transaction data generation unit 1012 records the generated transaction data in the recording unit 1014. The transaction data generation unit 1012 also transmits the generated transaction data to at least one of the authentication servers 200a, etc. via the communication unit 1015. When the transaction data generation unit 1012 receives a notification from the power meter 103 that power has been transmitted to the power network 500, it generates transaction data including the time and amount of transmitted power included in the notification, and records the transaction data in the recording unit 1014. The generated transaction data is transmitted to at least one of the authentication servers 200a, etc. via the communication unit 1015.

[0062] <Control unit 1013> When the amount of surplus power in the first power facility is equal to or greater than a predetermined value, the control unit 1013 transmits at least a portion of the surplus power as transmission power to the power storage facility via the power line. For example, when controlling power transmission, the control unit 1013 transmits to the solar power generation unit 102 a power transmission instruction indicating that power generated by the solar power generation unit 102 is to be transmitted to the power network 500. When controlling power utilization, the control unit 1013 utilizes power purchased via the power network 500.

[0063] Furthermore, the control unit 1013 may control a display built into or connected to the controller 101 to display the power sale request information or power purchase request information transmitted to the authentication server 200a or the like.

[0064] Furthermore, the control unit 1013 may cause the display to display power transmission information indicating that at least a portion of the surplus power has been transmitted as transmission power to the power storage facility via the power line.The control unit 1013 may cause the display to display verification in progress information indicating that the validity of the first transaction data is being verified, during the period from when the first transaction data is transmitted to a first server among the multiple authentication servers 200a, etc., until the validity of the first transaction data is verified by the multiple authentication servers 200a, etc.

[0065] Furthermore, when the authenticity of the first transaction data is verified by the plurality of authentication servers 200a, etc., the control unit 1013 may cause the display to display compensation information indicating the compensation to be paid to the user according to the amount of transmitted power. On the other hand, when the authenticity of the first transaction data is not verified by the plurality of authentication servers 200a, etc., the control unit 1013 may cause the display to display failure information indicating that the verification was not successful.

[0066] <Recording Unit 1014> The recording unit 1014 records the transaction data generated by the transaction data generation unit 1012. In this embodiment, the recording unit 1014 records the first transaction data or the second transaction data generated by the transaction data generation unit 1012.

[0067] <Communications Department 1015> The communication unit 1015 communicates with the management server 350, the authentication server 200a, etc. via the communication network 400. This communication may be performed using TLS (Transport Layer Security). In this case, the communication unit 1015 may hold an encryption key for TLS communication.

[0068] In this embodiment, the communication unit 1015 transmits the first transaction data or the second transaction data via the communication network 400 to a first server among the plurality of authentication servers 200a, etc.

[0069] Next, the authentication server 200a and the like will be described.

[0070] 1.4 Configuration of the authentication server 200a 5 is a block diagram showing the functional configuration of authentication server 200a according to this embodiment. Since authentication servers 200b and 200c have the same configuration, authentication server 200a will be taken as an example for explanation.

[0071] 5, the authentication server 200a includes a power storage status acquisition unit 211, a transaction data verification unit 212, a block generation unit 213, a synchronization unit 214, a transaction generation unit 215, a recording unit 216, and a communication unit 217. The authentication server 200a can be realized by a processor executing a predetermined program using a memory. Each component will be described below.

[0072] <Charge status acquisition unit 211> The power storage status acquiring unit 211 acquires, from the power storage equipment via the communication network 400, power reception information including power reception amount information indicating the amount of received power that the power storage equipment has received from the first power equipment. Furthermore, the power storage status acquiring unit 211 acquires, from the power storage equipment via the communication network 400, power storage information including power storage amount information indicating the amount of stored power held by the power storage equipment. Note that the power storage status acquiring unit 211 may acquire, from the power storage equipment via the communication network 400, power reception information including power reception amount information indicating the amount of received power that the power storage equipment has received from the first power equipment and a second timestamp indicating a second date and time when the received power was received.

[0073] In this way, the power storage status acquisition unit 211 acquires the power reception information and the power storage information as information indicating the power storage status of the storage battery 300, and confirms that power is indeed being stored in the storage battery 300. Then, the power storage status acquisition unit 211 transmits the acquired information indicating the power storage status of the storage battery 300 to the transaction data verification unit 212 and the transaction generation unit 215.

[0074] <Transaction Data Verification Unit 212> When the transaction data verification unit 212 receives first transaction data, it verifies the validity of the received first transaction data by referring to the received power information. More specifically, the transaction data verification unit 212 compares the transmitted power amount information with the received power amount information by referring to the received power information, and confirms that the transmitted power has indeed been stored in the storage battery 300. After this confirmation, the transaction data verification unit 212 verifies the digital signature of the first user and verifies the validity of the first transaction data. Note that the first transaction data may include a first timestamp, and the received power information may include a second timestamp. In this case, the transaction data verification unit 212 may compare the transmitted power amount information with the received power amount information by referring to the received power information, and confirm that the transmitted power has indeed been stored in the storage battery 300. By using the first timestamp and the second timestamp, the transaction data verification unit 212 can confirm that the power has been transmitted to the storage battery, as well as that the timing of the power transmission and reception is correct.

[0075] Furthermore, when the transaction data verification unit 212 receives second transaction data, it verifies the received second transaction data. More specifically, the transaction data verification unit 212 verifies the digital signature of the second user included in the second transaction data and the legitimacy of the second transaction data.

[0076] In this way, the transaction data verification unit 212 verifies the received transaction data. More specifically, when the transaction data verification unit 212 receives transaction data from the house 100a or the like, it verifies whether the blockchain address, the electricity storage request information or the electricity purchase request information, and the electricity information included in the transaction data are correct. If the transaction data verification unit 212 confirms the legitimacy of the transaction data as a result of the verification, it records the transaction data in the recording unit 216.

[0077] Furthermore, to verify whether the power information is correct, the transaction data verification unit 212 refers to the information indicating the power storage state of the storage battery 300 acquired by the power storage state acquisition unit 211, and verifies whether power is being transmitted or used correctly. If the transaction data verification unit 212 confirms the validity of the transaction data as a result of the verification, it notifies the synchronization unit 214 of the transaction data.

[0078] <Block Generation Unit 213> If the transaction data verification unit 212 successfully verifies the validity of the transaction data, the block generation unit 213 executes a consensus algorithm for the transaction data together with other authentication servers 200b and 200c, which are second servers different from the first server. The consensus algorithm here refers to the first to third consensus algorithms, and the transaction data refers to the first to third transaction data.

[0079] In this way, the block generation unit 213 executes a consensus algorithm among multiple authentication servers. The consensus algorithm may be a consensus algorithm called PBFT (Practical Byzantine Fault Tolerance), or any other known consensus algorithm. When PBFT is used, the block generation unit 213 first receives reports from each of the other authentication servers 200b, 200c indicating whether the transaction verification was successful or not, and determines whether the number of such reports exceeds a predetermined number. Then, when the number of such reports exceeds the predetermined number, the block generation unit 213 determines that the validity of the transaction data has been verified by the consensus algorithm.

[0080] Furthermore, if the validity of the transaction data is verified by the consensus algorithm, the block generation unit 213 records a block including the transaction data in the distributed ledger in the storage device 201a of the authentication server 200a.

[0081] As described above, in this embodiment, the block generation unit 213 executes a consensus algorithm between the authentication servers 200a, 200b, and 200c. That is, the block generation unit 213 first generates a block of a blockchain including one or more transaction data. Next, the block generation unit 213 executes the consensus algorithm. Then, when consensus is reached by executing the consensus algorithm, the block generation unit 213 records the generated block in the recording unit 216. The block generated by the block generation unit 213 is connected to the blockchain recorded in the recording unit 216 and recorded.

[0082] Here, the data structure of the blockchain and the data structure of the transaction data will be described.

[0083] FIG. 6A is an explanatory diagram showing the data structure of a blockchain.

[0084] A blockchain is a chain of blocks, which are the units of record. Each block contains multiple transaction data and the hash value of the previous block. Specifically, block B2 contains the hash value of the previous block B1. A hash value calculated from the multiple transaction data contained in block B2 and the hash value of block B1 is included in block B3 as the hash value of block B2. In this way, by connecting blocks in a chain while including the contents of the previous block as a hash value, tampering with the connected transaction data is effectively prevented.

[0085] If past transaction data were to be changed, the hash value of the block would be different from before the change, and in order to make the altered block appear correct, all subsequent blocks would have to be recreated, which is a very difficult task in reality.

[0086] In this embodiment, each transaction data represents first transaction data indicating a request to sell electricity, second transaction data indicating a request to buy electricity, and third and / or fourth transaction data indicating the matching result of the electricity transaction described below.

[0087] FIG. 6B is an explanatory diagram showing the data structure of the transaction data.

[0088] 6B is an example of the first to fifth transaction data. Transaction data D1 includes an address P1 indicating the holder, an address P2 indicating the recipient, and an electronic signature P3 generated by signing the hash values ​​of addresses P1 and P2 with the holder's signature key. When new transaction data is generated, address P1 is left blank.

[0089] <Synchronization unit 214> The synchronization unit 214 synchronizes the blocks of the blockchain or the transaction data among the multiple authentication servers (authentication servers 200a to 200c).

[0090] More specifically, if the verification of the user's digital signature included in the transaction data acquired from the house 100a and the verification of the legitimacy of the transaction data are successful, the synchronization unit 214 transfers a copy of the transaction data to the other authentication servers 200b and 200c. Here, the transaction data refers to the first to third transaction data, and the user's digital signature refers to the first user's digital signature or the second user's digital signature.

[0091] The multiple authentication servers 200a to 200c synchronize the transaction data of the blockchain on a peer-to-peer basis. Then, the synchronization unit 214 records the synchronized transaction data of the blockchain in the recording unit 216.

[0092] For example, when the validity of the first transaction data indicating a request to sell electricity or the second transaction data indicating a request to buy electricity is verified, the synchronization unit 214 transfers the contents of the first or second transaction data to the other authentication servers 200b and 200c. At the same time, the synchronization unit 214 records the verified transaction data in the recording unit 216.

[0093] Furthermore, when the synchronization unit 214 receives transaction data from the other authentication servers 200b and 200c, it records the transaction data in the recording unit 216.

[0094] <Transaction Generation Unit 215> The transaction generation unit 215 compares the power purchase amount information with the power storage amount information to determine whether power can be transmitted from the power storage facility to the second power facility, and if power can be transmitted from the power storage facility to the second power facility via the power line, requests the power storage facility to transmit power to the second power facility. In addition, the transaction generation unit 215 generates third transaction data indicating a matching result of the power transaction to the effect that stored power will be transmitted from the power storage facility to the second power facility.

[0095] In this embodiment, transaction generation unit 215 matches the electricity storage list recorded in recording unit 216 with the electricity purchase request list to determine whether the home that has made the electricity purchase request can purchase electricity. If transaction generation unit 215 determines that electricity purchase is possible, it requests management server 350 that manages storage battery 300 to transmit electricity to the home that has made the electricity purchase request, and generates transaction data and records it in recording unit 216.

[0096] FIG. 7A is a diagram showing an example of a power storage list according to this embodiment. As shown in FIG. 7A, the power storage list includes a blockchain address, a date of power storage, a stored amount, and a signature, and is recorded in the recording unit 216. For example, the first line of the power storage list shown in FIG. 7A records that a residence identified by the blockchain address "0x03547921" stored 30 kWh of power in the storage battery 300 by the date "1:00 PM on December 14, 2017." As such, each line of the power storage list lists the amount of stored power transmitted and accumulated by the residence identified by the blockchain address and the date of storage. As mentioned above, the blockchain address does not need to be uniquely determined for each residence, etc., as long as it can identify the residence, etc. Furthermore, because there is a time lag between the time of power transmission and the time of power reception, the date does not need to indicate the exact time, etc., as long as it can correctly identify the date. Similarly, since there is a transmission loss, the stored amount does not strictly match the transmitted amount, but may be treated as the same as long as it is within a predetermined range taking the transmission loss into account.

[0097] FIG. 7B is a diagram showing an example of a power purchase request list according to the present embodiment. As shown in FIG. 7B, the power purchase request list includes a blockchain address, a desired date for power purchase, a desired amount of power to be purchased, a unit price for the power purchase, and a signature. For example, the first line of the power purchase request list in FIG. 7B records that a house identified by the blockchain address "0x04587463" wishes to purchase 10 kWh of power at a unit price of 20 yen on the date "December 15, 2017, 1:30 PM." In this way, each line of the power purchase request list describes the unit price and amount of power that the house, identified by the blockchain address, wishes to purchase on a desired date and time.

[0098] The signature performed by authentication server 200a shown in FIGS. 7A and 7B is not essential and may be omitted.

[0099] Therefore, the transaction generation unit 215 determines whether electricity can be transmitted to the house that has requested the purchase of electricity by referring to and comparing the dates and amounts of electricity in the electricity storage list shown in, for example, Figure 7A with the dates and amounts of electricity to be purchased in the electricity purchase request list shown in, for example, Figure 7B and performing matching.

[0100] When the transaction generation unit 215 determines that it is possible to transmit the electricity desired by the house that has made the electricity purchase request, it generates transaction data indicating the matching result of the electricity transaction, including the blockchain address of the electricity transmission destination, the date, the amount of electricity, and the unit price. At the same time, the transaction generation unit 215 requests the management server 350 that manages the storage battery 300 to transmit electricity to the house that has made the electricity purchase request. The transaction generation unit 215 then records the generated transaction data in the recording unit 216. Note that while the transaction generation unit 215 requests the management server 350 to transmit electricity to the house that has made the electricity purchase request, it may also be possible to set a higher unit price to preferentially match with the house that has made the electricity purchase request.

[0101] FIG. 8 is a diagram showing an example of a power purchase list according to this embodiment. The power purchase list shown in FIG. 8 is a matching result of an energy transaction performed by the transaction generation unit 215, and is an example of an energy transaction list showing to whom, how much energy was sold, and when. As shown in FIG. 8, the power purchase list is composed of the blockchain address of the power purchase destination, a date, an amount of energy, and a unit price. The power purchase list also includes a signature of the authentication server, but this is not shown here. As such, each line of the power purchase list includes the blockchain address of the power buyer indicating the home that has requested the power purchase and for which matching in the energy transaction has been established, the amount of energy to be traded in the energy transaction, and its unit price.

[0102] Furthermore, the transaction generation unit 215 generates transaction data indicating the matching result of the energy transaction, including the information shown in the row of the energy purchase list in Fig. 8, and records the data in the recording unit 216. After generating the energy transaction data indicating the matching result of the energy transaction, the transaction generation unit 215 notifies the energy transaction result indicating the details of the energy transaction to the home 100a, etc. that will be conducting the energy transaction, i.e., where the energy purchase will be implemented. The transaction generation unit 215 may periodically broadcast the energy transaction result, or may directly notify the home that will be conducting the energy transaction if the home can be identified by its blockchain address.

[0103] Furthermore, after the step of recording the block including the first transaction data in the distributed ledger, the transaction generation unit 215 may further notify the first user that the incentive has been paid after the first authentication server has paid the incentive. In this embodiment, the transaction generation unit 215 pays the incentive to the home 100a that transmitted the electricity. After the incentive has been paid, the transaction generation unit 215 notifies the home 100a that transmitted the electricity of this fact. Furthermore, the transaction generation unit 215 may encourage the payment of the incentive by notifying the home 100a, etc., where the electricity is purchased, of an electricity transaction result indicating the details of the electricity transaction.

[0104] The incentive may be paid by cash transfer, by paying energy trading points, or by paying virtual currency using blockchain. In this way, the incentive is also paid to the home 100a, etc. that transmitted the amount of purchased power. After the incentive is paid to the home 100a, etc. that transmitted the amount of purchased power, the transaction generation unit 215 may notify the home 100a, etc. that transmitted the amount of purchased power that the incentive has been paid.

[0105] <Recording Unit 216> The recording unit 216 records the transaction data of the blockchain in blocks in the storage device 201a. The storage device 201a may be configured inside the recording unit 216, or may be configured outside the authentication server 200a as shown in Fig. 1. This transaction data means first transaction data indicating a request to sell electricity, second transaction data indicating a request to buy electricity, first transaction data indicating a request to sell electricity, second transaction data indicating a request to buy electricity, and third transaction data indicating a matching result of the electricity transaction.

[0106] <Communications Department 217> The communication unit 217 communicates with two or more residences 100a, etc., other authentication servers 200b, 200c, and the management server 350. More specifically, the communication unit 217 is a communication interface that communicates with two or more residences 100a, etc., other authentication servers 200b, 200c, and the management server 350. Communication with two or more residences 100a, etc. and the management server 350 may be performed using TLS. In this case, an encryption key for TLS communication may be held in the communication unit 217.

[0107] [1.5 Configuration of Management Server 350] Fig. 9 is a block diagram showing the functional configuration of a management server 350 according to this embodiment. As shown in Fig. 9, the management server 350 includes a power control unit 311, a storage battery control unit 312, a recording unit 313, and a communication unit 314, and manages the storage battery 300. The storage battery 300 and the management server 350 are an example of a power storage facility, and may be referred to as the storage battery side below.

[0108] <Power control unit 311> The power control unit 311 instructs the storage battery control unit 312 to store the amount of power transmitted from the house 100a, etc. in the storage battery 300, and records the amount of power stored in the storage battery 300 as the amount of received power in the recording unit 313. Furthermore, when the power control unit 311 acquires a power transmission request from the authentication server 200a, etc., it instructs the storage battery control unit 312 to control the storage battery 300 to transmit the power stored in the storage battery 300 to the house 100a, etc., which is the power transmission destination included in the power transmission request.

[0109] Furthermore, when the power control unit 311 receives an inquiry about the power storage state of the storage battery 300 from the authentication server 200a or the like, it transmits power reception information including the received power amount or power storage information including the stored power amount, which is recorded in the recording unit 313 as information indicating the power storage state of the storage battery 300. Here, as described above, the power reception information includes received power amount information indicating the amount of received power received by the power storage equipment from the first power equipment, and a second timestamp indicating a second date and time when the received power was received. In other words, the power reception information includes received power amount information indicating the amount of received power received from the house 100a or the like, and the date and time when the received power was received. Furthermore, the power storage information includes stored power amount information indicating the amount of stored power held by the power storage equipment. In other words, the power storage information includes stored power amount information indicating the current amount of power stored in the storage battery 300.

[0110] <Storage battery control unit 312> Upon receiving an instruction from the power control unit 311, the storage battery control unit 312 controls the storage battery 300. For example, the storage battery control unit 312 controls the storage battery 300 to transmit the power stored in the storage battery 300 to the house 100a or the like that is the power transmission destination included in the power transmission request. The storage battery control unit 312 controls the storage battery 300 to transmit the power stored in the storage battery 300 to the house 100a or the like that is the power transmission destination included in the power transmission request. The storage battery control unit 312 also acquires, from the storage battery 300, power reception information including the amount of received power or power storage information including the amount of stored power, as information indicating the power storage state of the storage battery 300.

[0111] <Recording Unit 313> The recording unit 313 records information indicating the power storage state of the storage battery 300, which is acquired from the storage battery 300. In this embodiment, the recording unit 313 records the power reception information or power storage information acquired from the storage battery 300.

[0112] <Communications Department 314> The communication unit 314 communicates with the house 100a and the authentication server 200a via the communication network 400. This communication may be performed using TLS. In this case, the communication unit 314 may store an encryption key for the TLS communication.

[0113] The management server 350 does not have to be provided in the energy trading system 10. In this case, among the functional components of the management server 350 described above, the storage battery control unit 312 may be configured in the authentication server 200a or the like, and the power control unit 311, the recording unit 313, and the communication unit 314 may be configured in the storage battery 300. Then, the authentication server 200a or the like and the storage battery 300 may directly communicate with each other without going through the management server 350. In this case, the storage battery 300 corresponds to an example of a power storage facility.

[0114] [1.6 Overall sequence of electricity trading between a home and an authentication server] Next, a sequence of an energy transaction between the house 100a etc. and the authentication server 200a etc. will be described. Fig. 10 is an overall sequence diagram of an energy transaction according to this embodiment. Each process will be described later.

[0115] First, in step S100, a power selling process is performed between, for example, the house 100a and the authentication servers 200a, 200b, and 200c. Next, in step S200, a power buying process is performed between, for example, the house 100c and the authentication servers 200a, 200b, and 200c.

[0116] Either the power selling process in step S100 or the power purchasing process in step S200 may be executed first, and they are performed irregularly.

[0117] [1.6.1 Power selling process between the home and the authentication server] Next, the power selling process between the house 100a and the authentication server 200a will be described.

[0118] Fig. 11 is a sequence diagram of the power selling process according to the present embodiment. In Fig. 11, the explanation is given assuming that the house 100a sells power as an example, but this is not limiting. The same sequence may be followed for other houses such as the house 100b.

[0119] First, in step S101, if the controller 101 or the user of the house 100a wishes to sell surplus power generated by the solar power generation system 102, the controller 101 or the user inputs power sale request information and transmits the power. For example, surplus power may be generated when the amount of power used by the house 100a is less than the amount of power generated by the solar power generation system 102. In this case, the surplus power is transmitted to the storage battery side automatically after the user inputs the power sale request information, or when the controller 101 is set to automatically transmit power. Note that, as described above, the storage battery side means the management server 350 when there is a management server 350 that manages the storage battery 300, or means the storage battery 300 when there is no management server 350.

[0120] Next, in step S103, the controller 101 of the house 100a generates transaction data indicating the power sale request (hereinafter referred to as first transaction data) based on the input power sale request information. As described above, the first transaction data includes a blockchain address, a date, an amount of power sold, and a signature.

[0121] Next, in step S104, the controller 101 of the house 100a transmits the generated first transaction data to the authentication server 200a. Note that in the example shown in Fig. 11, the controller 101 of the house 100a transmits the generated first transaction data to the authentication server 200a, but it may also transmit it to other authentication servers 200b, 200c. The same applies when transmitting the data to other authentication servers 200b, 200c.

[0122] Next, in step S105, when the authentication server 200a receives the first transaction data from the house 100a, it first inquires about the power storage state of the storage battery 300.

[0123] Next, in step S106, the storage battery side transmits, as a response to the inquiry about the power storage state of the storage battery 300, power reception information including power reception amount information indicating the amount of power received by the storage battery 300 from the house 100a.

[0124] Next, in step S107, upon receiving the power reception information from the storage battery, authentication server 200a verifies the first transaction data received from house 100a. As described above, verification of the first transaction data includes at least verifying the legitimacy of the first transaction data and verifying whether the power information, such as whether power was transmitted and received correctly, is correct.

[0125] In step S107, if the verification of the first transaction data is not successful (N in S107), authentication server 200a transmits a notification to that effect to residence 100a (S108), and ends the process.

[0126] On the other hand, if the authentication server 200a successfully verifies the first transaction data in step S107 (Y in S107), it transfers the first transaction data to the other authentication servers 200b and 200c (S109).The other authentication servers 200b and 200c also similarly verify the received first transaction data.

[0127] Next, in step S110, authentication server 200a, authentication server 200b, and authentication server 200c execute a consensus algorithm. When authentication server 200a, authentication server 200b, and authentication server 200c verify that the first transaction data is legitimate transaction data (i.e., legitimacy), they each generate a block including the first transaction data. Then, authentication servers 200a, 200b, and 200c record the block including the first transaction data in the distributed ledgers of storage devices 201a, 201b, and 201c.

[0128] Next, in step S111, the authentication server 200a pays an incentive to the house 100a to which the electricity has been transmitted. The incentive may be paid by transferring cash, by paying energy trading points, or by paying virtual currency using a blockchain.

[0129] Next, in step S112, the authentication server 200a transmits a notification to the home 100a to which the power has been transmitted that the incentive has been paid.

[0130] [1.6.2 Power purchase process between the home and the authentication server] Next, the power purchasing process between the house 100a, etc. and the authentication server 200a, etc. will be described. Fig. 12 and Fig. 13 are sequence diagrams of the power purchasing process according to this embodiment. In Fig. 12 and Fig. 13, the power purchasing process will be described as being performed by the house 100c as an example, but this is not limited to this. The same power purchasing process sequence will also be performed for other houses, such as the house 100b.

[0131] First, in step S201, the controller 101 or the user of the house 100c inputs power purchase request information if they wish to purchase power. The controller 101 or the user of the house 100c purchases power, for example, when power usage in the house 100c is high and it is cheaper to purchase surplus power stored in the storage battery 300 from a service provider that owns the storage battery 300 than to purchase power from a power company.

[0132] Next, in step S203, the controller 101 of the home 100c generates transaction data indicating the power purchase request (hereinafter referred to as second transaction data) based on the input power purchase request information. As described above, the second transaction data includes a blockchain address, power purchase amount information indicating the amount of power to be purchased, and a digital signature of the user of the home 100c.

[0133] Next, in step S204, the controller 101 of the house 100c transmits the generated second transaction data to the authentication server 200c. Note that in the example shown in Fig. 12, the controller 101 of the house 100c transmits the generated second transaction data to the authentication server 200c, but it may also transmit it to another authentication server 200a, 200b. The same applies when transmitting it to another authentication server 200a, 200b.

[0134] Next, in step S205, the authentication server 200c verifies the second transaction data received from the residence 100c.

[0135] In step S205, if the verification of the second transaction data is not successful (N in S205), authentication server 200c transmits a notification to that effect to residence 100c (S206), and ends the process.

[0136] On the other hand, if the authentication server 200c succeeds in verifying the second transaction data in step S205 (Y in S205), it transfers the second transaction data to the other authentication servers 200a and 200b (S207). The other authentication servers 200b and 200c also verify the received second transaction data in the same manner.

[0137] Next, in step S208, authentication server 200a, authentication server 200b, and authentication server 200c execute a consensus algorithm. When authentication server 200a, authentication server 200b, and authentication server 200c verify that the second transaction data is legitimate (i.e., validity), they each generate a block containing the second transaction data. Then, authentication servers 200a, 200b, and 200c record the block containing the second transaction data in the distributed ledger of storage devices 201a, 201b, and 201c.

[0138] Next, as shown in FIG. 13, in step S209, the authentication server 200c inquires about the power storage state of the storage battery 300.

[0139] Next, in step S210, the storage battery side transmits power storage information indicating the amount of stored power currently held by the storage battery 300 as a response to the inquiry about the power storage state of the storage battery 300.

[0140] Next, in step S211, the authentication server 200c acquires the power storage information from the storage battery and determines whether or not power can be transmitted to the home 100c that has requested the power purchase, based on the acquired power storage information and the power purchase request list. The power storage information indicates the power storage state of the storage battery 300. The power purchase request list also lists the unit price and amount of power that each home, identified by its blockchain address, wishes to purchase on a desired date and time.

[0141] In step S211, if the authentication server 200c determines that power transmission is not possible (N in S211), it transmits a notice to that effect to the house 100c (S212), and ends the process.

[0142] On the other hand, in step S211, if the authentication server 200c determines that power transmission is possible (Y in S211), it transmits a power transmission request to the storage battery side (S213). Note that, in addition to transmitting the power transmission request, the authentication server 200c may also notify the house 100c of a reservation confirmation notice indicating that power transmission is possible.

[0143] Next, in step S214, when the storage battery side receives the power transmission request from the authentication server 200c, it transmits the power stored in the storage battery 300 to the house 100c, which is the power transmission destination included in the power transmission request.

[0144] Next, in step S215, the authentication server 200c generates transaction data (hereinafter referred to as third transaction data) indicating a matching result of the electricity transaction to the effect that stored electricity will be transmitted from the storage battery side to the house 100c. Note that the authentication server 200c may generate the third transaction data after confirming that electricity has been transmitted from the storage battery side to the house 100c.

[0145] Next, in step S216, authentication server 200c transfers the generated third transaction data to the other authentication servers 200a and 200b, which similarly verify the received third transaction data.

[0146] Next, in step S217, authentication server 200a, authentication server 200b, and authentication server 200c execute a consensus algorithm. When authentication server 200a, authentication server 200b, and authentication server 200c verify that the third transaction data is legitimate transaction data (i.e., legitimacy), they each generate a block including the third transaction data. Then, authentication servers 200a, 200b, and 200c record the block including the third transaction data in the distributed ledger of storage devices 201a, 201b, and 201c.

[0147] In step S213, when the authentication server 200c transmits the power transmission request to the storage battery, the authentication server 200c may generate transaction data (hereinafter referred to as fourth transaction data) indicating the matching result of the energy transaction, indicating that the energy storage facility has requested the second power facility to transmit stored energy. In this case, the authentication server 200c transfers the generated fourth transaction data to the other authentication servers 200a and 200b. Next, the authentication servers 200a, 200b, and 200c execute a consensus algorithm. When the authentication servers 200a, 200b, and 200c verify that the third transaction data is legitimate transaction data (i.e., legitimacy), they each generate a block including the fourth transaction data. Then, the authentication servers 200a, 200b, and 200c record the block including the fourth transaction data in the distributed ledger of the storage devices 201a, 201b, and 201c.

[0148] In this way, by recording a block including the fourth transaction data, it is possible to indicate that the reservation for power transmission has been completed.

[0149] Furthermore, in this case, as shown in steps S214 to S217, when the power transmission is completed in step S214, a fourth transaction is further generated that includes information indicating that the storage battery side has transmitted power, and a consensus algorithm is executed between authentication server 200a, authentication server 200b, and authentication server 200c to record the fourth transaction.

[0150] As a result, before generating the third transaction indicating the matching result of the energy trade, a fourth transaction indicating the reservation for power transmission is generated and recorded on the distributed ledger. This makes it possible to reliably record the matching result of the energy trade and the reservation for power transmission as evidence, even if there is a time lag between the timing of the matching of the energy trade and the time of transmission.

[0151] [1.7 Effects, etc.] As described above, according to the energy trading system 10 etc. according to the embodiment, transaction data of the transaction of electricity transmitted to the storage battery 300, for example, is recorded in a distributed ledger. This makes the transaction data of the electricity transaction public, enabling tampering detection, thereby preventing fraudulent energy trading by service providers that own storage batteries. For example, it is possible to verify the consistency between the electricity transmitted to the energy storage facility and the electricity received by the energy storage facility, as well as the validity of the first transaction data, thereby enabling tampering detection.

[0152] Furthermore, the energy trading system 10 according to the embodiment may record second blockchain transaction data indicating an electricity purchase request in the distributed ledger. Furthermore, the energy trading system 10 according to the embodiment may record third blockchain transaction data indicating a matching result of an electricity transaction via a storage battery in the distributed ledger. This makes the transaction data of the electricity transaction public and enables tampering detection, thereby preventing fraudulent energy transactions by service providers who own the storage battery 300.

[0153] As described above, according to the energy trading system 10 etc. according to the embodiment, when peer-to-peer electricity trading is entrusted to an intermediary that owns a storage battery 300, blockchain technology is utilized to make public energy trading transaction data indicating the electricity selling process, the electricity purchase request process, and the electricity purchase process. This prevents the intermediary that owns the storage battery 300 from selling electricity at a price that is unreasonably higher than the price at which the electricity was purchased, purchasing electricity at a price that is unreasonably lower than the average desired purchasing price, or refusing to purchase electricity despite having stored electricity. In other words, according to the energy trading system 10 etc. according to the embodiment, transparency can be provided to the price at which electricity is traded, thereby preventing service providers that own the storage battery 300 from unfairly manipulating prices during energy trading and thereby preventing fraudulent energy trading.

[0154] Furthermore, because the intermediary owns the storage battery 300, there is no need for each home to own a storage battery, and users who wish to purchase electricity only need to make a request to the intermediary. This also has the effect of making the energy trading system 10 etc. according to the embodiments an easy-to-implement system.

[0155] [2. Other variations] Although the present disclosure has been described based on the above-described embodiments, it goes without saying that the present disclosure is not limited to the above-described embodiments. The following cases are also included in the present disclosure.

[0156] (1) The authentication server 200a, etc. may generate transaction data when an incentive is paid and record it in the storage device 201a, etc. of the authentication server 200a, etc. This transaction data may include the blockchain address to which the incentive was paid, information indicating the content of the incentive, and the signature of the authentication server 200a, etc.

[0157] (2) If an electricity transaction with a house that has made a power purchase request is not concluded, the authentication server 200a etc. may resubmit the electricity purchase request. This makes it possible to reset the time and / or the electricity unit price in the electricity purchase request, and to re-determine whether or not the electricity transaction can be concluded.

[0158] (3) When electricity is purchased in response to a power purchase request, the purchasing user may pay the electricity trading service company directly, or may pay with points or virtual currency earned from previous electricity sales.

[0159] (4) In the example described in FIG. 11 of the above embodiment, the authentication server 200a pays an incentive to the user of the home 100a that sold the electricity after the electricity is sold to the storage battery, but this is not limited to this. The authentication server 200a may pay the incentive to the user of the home 100a that sold the electricity after processing payment from the user of the home 100c that purchased the electricity. Furthermore, the authentication server 200a may pay the incentive to the user of the home 100a that sold the electricity in a lump sum for each period, rather than for each electricity sale transaction.

[0160] (5) In the above embodiment, the authentication server 200a etc. determines whether to transmit electricity, but this is not limited to this. The authentication server 200a etc. may use a smart contract function of a blockchain to install a program in advance to determine whether an electricity transaction, such as whether electricity can be transmitted, can be concluded, and the authentication server 200a etc. may automatically determine whether to conduct an electricity transaction.

[0161] (6) In the above embodiment, the user inputs the unit price of power purchase, but this is not limited to this. The authentication server 200a or the like may set the unit price of power sale and / or the unit price of power purchase, and the user may select the unit price. Furthermore, the unit price of power sale and the unit price of power purchase may be changed depending on the time.

[0162] (7) In the above embodiment, the authentication server 200a, etc. determines whether or not to transmit electricity based on the amount of stored electricity, the time, and the unit price. However, the determination may also take into account the ease of transmitting electricity over the electricity network. For example, when electricity is transmitted from a home selling electricity to a home buying electricity via an electricity network, the authentication server 200a, etc. may prioritize matching electricity transactions with homes that are closer in distance. Furthermore, the authentication server 200a, etc. may prioritize matching electricity transactions with homes that experience less power loss during transmission over the electricity network. This reduces power loss across the entire energy trading service.

[0163] (8) The authentication server 200a or the like may issue a token for the right to use the power of the storage battery, and the user of the house who buys the power may purchase the token. This allows the user who buys the power to purchase the right to use the power in advance.

[0164] (9) When power is transmitted from a house to the storage battery 300, the management server 350 that manages the storage battery 300 may generate transaction data including the date and the amount of power transmitted and stored. Also, when power is transmitted from the storage battery 300 to a house, the management server 350 that manages the storage battery 300 may generate transaction data including the date and the amount of power transmitted. The management server 350 may transmit the generated transaction data to the authentication server 200a or the like, so that the generated transaction data may be managed in a blockchain.

[0165] (10) In the above embodiment, the authentication server 200a etc. determines whether or not power transmission is possible based on the power storage information and the power purchase request information. If the authentication server 200a etc. determines that power transmission is impossible, it may further notify each home of a power sale request. Furthermore, the power sale request after the notification may increase the unit price of power sale. This allows the amount of power stored in the storage battery 300 to be increased, enabling power transmission to the home.

[0166] (11) Furthermore, the management server 350 may transmit the power storage information to the authentication server 200a, etc. periodically or when there is a change in the power storage state of the storage battery 300. At this time, the management server 350 may generate transaction data including the power storage state and the date, and transmit the transaction data to the authentication server 200a, etc.

[0167] (12) Furthermore, the selling price and / or purchasing price of electricity may be set depending on the state of electricity stored in the storage battery 300.

[0168] (13) The present disclosure also includes a data structure used for blocks recorded as a blockchain in the energy trading system 10 of the above-described embodiment. More specifically, the data structure of the present disclosure is a data structure used for blocks recorded as a blockchain in an energy trading system including a first power facility used by a first user, a power storage facility connected to the first power facility via a power line, and a plurality of servers with which the first power facility and the power storage facility can communicate via a network. The data structure includes a blockchain address, which is an identifier included in the blockchain block and generated using the private key of the first user, for identifying at least one of the first user and the first power facility; transmitted power amount information indicating the amount of transmitted power transmitted by the first power facility to the power storage facility; and a digital signature of the first user. The transmitted power amount information included in the data structure of the present disclosure is compared with purchased power amount information indicating the amount of received power received by the power storage facility from the first power facility, and is used to verify the legitimacy of a transaction related to power transmission. In some cases, the first transaction data includes a first timestamp and the power reception information includes a second timestamp. In this case, the first timestamp and the second timestamp can be used to confirm that power has been transmitted to the storage battery, and also to confirm that the timing of power transmission and reception is correct.

[0169] (14) Each device in the above embodiments is specifically a computer system comprising a microprocessor, ROM, RAM, hard disk unit, display unit, keyboard, mouse, etc. A computer program is recorded in the RAM or hard disk unit. Each device achieves its function by the microprocessor operating in accordance with the computer program. Here, the computer program is composed of a combination of multiple instruction codes that indicate commands to a computer to achieve a predetermined function.

[0170] (15) In each of the above embodiments, some or all of the constituent elements may be configured from a single system LSI (Large Scale Integration). A system LSI is an ultra-multifunctional LSI manufactured by integrating multiple components on a single chip, and specifically, is a computer system configured to include a microprocessor, ROM, RAM, etc. A computer program is recorded in the RAM. The system LSI achieves its functions when the microprocessor operates in accordance with the computer program.

[0171] Furthermore, each of the components constituting each of the above devices may be individually integrated into a single chip, or some or all of them may be integrated into a single chip.

[0172] Although we refer to it as a system LSI here, it may also be called an IC, LSI, super LSI, or ultra LSI depending on the level of integration. Furthermore, the method of integration is not limited to LSI; it can also be realized using dedicated circuits or general-purpose processors. It is also possible to use FPGAs (Field Programmable Gate Arrays), which can be programmed after LSI manufacturing, or reconfigurable processors, which allow the connections and settings of circuit cells within LSI to be reconfigured.

[0173] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology can be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0174] (16) Some or all of the components constituting each of the above devices may be configured as an IC card or a standalone module that can be attached to each device. The IC card or module is a computer system composed of a microprocessor, ROM, RAM, etc. The IC card or module may include the above-mentioned ultra-multifunctional LSI. The IC card or module achieves its functions when the microprocessor operates according to a computer program. The IC card or module may be tamper-resistant.

[0175] (17) The present disclosure may be embodied as the methods described above, a computer program for implementing these methods on a computer, or a digital signal comprising the computer program.

[0176] The present disclosure may also be a computer program or a digital signal recorded on a computer-readable recording medium, such as a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD (Blu-ray (registered trademark) Disc), a semiconductor memory, etc. Alternatively, the present disclosure may be a digital signal recorded on such a recording medium.

[0177] Furthermore, the present disclosure may also be applied to transmitting the computer program or the digital signal via a telecommunications line, a wireless or wired communication line, a network such as the Internet, data broadcasting, or the like.

[0178] The present disclosure may also be a computer system having a microprocessor and a memory, the memory storing the computer program, and the microprocessor operating in accordance with the computer program.

[0179] The program or the digital signal may also be implemented by another independent computer system by recording it on the recording medium and transferring it, or by transferring it via the network or the like.

[0180] (18) The above-described embodiments and modifications may be combined with each other. [Industrial Applicability]

[0181] The present disclosure provides an energy trading system that enables energy trading while eliminating fraud by managing transaction data on electricity sales, electricity purchases, and electricity trading information in an authentication server. [Explanation of symbols]

[0182] 100a, 100b, 100c Housing 101 Controller 102 Solar power generation 103 Power Meter 110, 400 communication network 111,500 Electricity Network 200a, 200b, 200c authentication servers 211 Power storage status acquisition unit 212 Transaction Data Verification Unit 213 Block Generation Unit 214 Synchronization Unit 215 Transaction Generation Unit 216, 313 Recording Department 217, 314 Communications Department 300 storage battery 311 Power Control Unit 312 Battery control unit 1011 Input section 1012 Transaction Data Generation Unit 1013 Control unit 1014 Recording section 1015 Communications Department

Claims

1. 1. A control method executed by a server in an energy trading system including a second power facility, a power storage facility connected to the second power facility, and a server with which the second power facility and the power storage facility can communicate via a network, comprising: Acquire transaction data from the second power facility, the transaction data including power purchase amount information indicating the amount of power to be purchased; determining whether a distance between the second power facility and the power storage facility is within a predetermined range or whether an amount of loss of power transmitted from the power storage facility to the second power facility is within a predetermined range; requesting the power storage equipment to transmit power to the second power equipment when it is determined that the distance between the second power equipment and the power storage equipment is within a predetermined range, or when it is determined that the amount of loss of power transmitted from the power storage equipment to the second power equipment is within a predetermined range; Control method.

2. the energy trading system further includes a first power facility that transmits power to the power storage facility; In the determination, it is further determined whether or not a distance between the first power facility and the power storage facility is within a predetermined range, or whether or not an amount of loss of power transmitted from the first power facility to the power storage facility is within a predetermined range; requesting the power storage equipment to transmit power to the second power equipment when it is determined that the distance between the first power equipment and the power storage equipment is within a predetermined range, or when it is determined that the amount of loss of power transmitted from the first power equipment to the power storage equipment is within a predetermined range; The control method according to claim 1 .

3. the energy trading system further includes a first power facility that transmits power to the power storage facility; In the determination, it is further determined whether or not a distance between the first power facility and the second power facility is within a predetermined range, or whether or not an amount of loss of power transmitted from the first power facility to the second power facility is within a predetermined range; requesting the power storage facility to transmit power to the second power facility when it is determined that the distance between the first power facility and the second power facility is within a predetermined range, or when it is determined that the amount of loss of power transmitted from the first power facility to the second power facility is within a predetermined range; The control method according to claim 1 .

4. the energy trading system further includes one or more third electric power facilities; In the determination, it is further determined whether or not a distance between the second power facility and the power storage facility is shorter than a distance between the one or more third power facilities and the power storage facility; If it is determined that the difference is smaller, the power storage facility is requested to transmit power to the second power facility with priority over the one or more third power facilities. The control method according to claim 1 .

5. The second power facility includes at least one of a solar power generation device, a gas power generation device, and a wind power generation device. The control method according to any one of claims 1 to 4.

6. The determination is performed by a smart contract. The control method according to any one of claims 1 to 4.

7. An energy trading system including: a second power facility; a power storage facility connected to the second power facility; and a server with which the second power facility and the power storage facility can communicate via a network, The server Acquire transaction data from the second power facility, the transaction data including power purchase amount information indicating the amount of power to be purchased; determining whether a distance between the second power facility and the power storage facility is within a predetermined range or whether an amount of loss of power transmitted from the power storage facility to the second power facility is within a predetermined range; requesting the power storage equipment to transmit power to the second power equipment when it is determined that the distance between the second power equipment and the power storage equipment is within a predetermined range, or when it is determined that the amount of loss of power transmitted from the power storage equipment to the second power equipment is within a predetermined range; Energy trading system.

8. A program causing a computer to execute a control method in an energy trading system including a second power facility, a power storage facility connected to the second power facility, and a server with which the second power facility and the power storage facility can communicate via a network, the program comprising: Acquire transaction data from the second power facility, the transaction data including power purchase amount information indicating the amount of power to be purchased; determining whether a distance between the second power facility and the power storage facility is within a predetermined range or whether an amount of loss of power transmitted from the power storage facility to the second power facility is within a predetermined range; requesting the power storage equipment to transmit power to the second power equipment when it is determined that the distance between the second power equipment and the power storage equipment is within a predetermined range, or when it is determined that the amount of loss of power transmitted from the power storage equipment to the second power equipment is within a predetermined range; A program that is executed by a computer.

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