Trading systems, nodes, blockchain networks, processing methods, and programs

Abstract

To trade electricity used by one user in different places, using a blockchain, in association.SOLUTION: A transaction system includes a node in a blockchain network, a communicable mediation system, a transaction server, and an electricity measurement apparatus, the mediation system including a communication unit which transmits an identifier, electricity consumed, place of use, and destination of electricity, to the node, the identifier identifying a user who purchases electricity received from the electricity measurement apparatus. The node includes: a storage unit which stores asset information including the identifier, electricity consumed, place of use, and destination of electricity; a reading unit which reads, from the asset information, transaction information related to the electricity consumed, place of use, and destination of electricity of the user; and a communication unit which transmits the transaction information extracted by the reading unit to the mediation system. The transaction server includes a communication unit which receives the transaction information from the mediation system, a calculation unit which calculates a first amount to be paid, on the basis of the transaction information, and a processing unit which executes payment processing.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a trading system, a node, a blockchain network, a processing method, and a program.

Background Art

[0002] In recent years, power generated by renewable energy has attracted attention. This power is produced by using resources that are renewable energy such as sunlight, solar heat, wind power, biomass, geothermal energy, hydropower, heat in the atmosphere, etc. Power generation by renewable energy hardly emits carbon dioxide that causes global warming compared to power generation by fossil fuels such as petroleum, coal, and liquefied natural gas. Therefore, among the resources used for power production, renewable energy is an environmentally friendly energy resource. By operating factories, etc. using such environmentally friendly green power, corporate value can be improved. On the other hand, a method of trading digital assets using a distributed ledger is known (for example, see Patent Document 1), and it is also possible to use a blockchain for trading power produced by renewable energy, etc.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, in the conventional technology, in power trading using a blockchain, power used at a predetermined place such as a home and power used at other places cannot be treated as transactions of the same user. For example, a transaction that sums up the power used to charge an electric vehicle using a charging device located outside the home and the power used at home was not possible.

[0004] In view of the above problems, an embodiment of the present invention aims to handle transactions of power used by the same user at different places in association with each other in power trading using a blockchain.

Means for Solving the Problems

[0005] To solve the above-mentioned problems, the present invention provides a transaction system having nodes in a blockchain network, an intermediary system capable of communicating with the nodes, a transaction server capable of communicating with the intermediary system, and at least one power measuring device, wherein the intermediary system comprises a first communication unit that transmits to the node an identifier identifying the user purchasing power, the amount of power used, the location of power use, and the destination of power use, which are received from the power measuring device; the node comprises a storage unit that stores asset information including an identifier, the amount of power used, the location of use, and the destination of power use, which are received from the intermediary system, a reading unit that extracts transaction information relating to the amount of power used, the location of use, and the destination of power use for a specified user during a specified transaction period from the asset information using the identifier, and a second communication unit that transmits the transaction information extracted by the reading unit to the intermediary system; and the transaction server comprises a third communication unit that receives transaction information from the intermediary system, a calculation unit that calculates a first payment fee based on the transaction information, and a processing unit that executes the payment processing for the first payment fee. [Effects of the Invention]

[0006] According to embodiments of the present invention, in electricity trading using blockchain technology, electricity transactions used by the same user in different locations can be linked and handled accordingly. [Brief explanation of the drawing]

[0007] [Figure 1] This figure shows an example of a schematic diagram of a trading system according to an embodiment of the present invention. [Figure 2] This figure shows an example of a flowchart relating to the processing of electricity transactions according to an embodiment of the present invention. [Figure 3] This figure shows an example of the hardware configuration of an information terminal according to an embodiment of the present invention. [Figure 4] This figure shows an example of the hardware configuration of an information processing device according to an embodiment of the present invention. [Figure 5] This figure shows an example of the hardware configuration of a charging device according to an embodiment of the present invention. [Figure 6] This figure shows an example of a configuration diagram of a functional block in a trading system according to an embodiment of the present invention. [Figure 7] This figure shows an example of a sequence of steps related to the process of registering new user information according to an embodiment of the present invention. [Figure 8] This figure shows an example of a login screen according to an embodiment of the present invention. [Figure 9] This figure shows an example of a user information registration screen according to an embodiment of the present invention. [Figure 10] This figure shows an example of user information according to an embodiment of the present invention. [Figure 11] This figure shows an example of purchaser information according to an embodiment of the present invention. [Figure 12] This figure shows an example of a user information registration completion screen according to an embodiment of the present invention. [Figure 13] This figure shows an example of a sequence relating to the process of purchasing electricity according to an embodiment of the present invention. [Figure 14] This figure shows an example of a power purchase screen according to an embodiment of the present invention. [Figure 15] This figure shows an example of a payment fee calculation result screen according to an embodiment of the present invention. [Figure 16] This figure shows an example of a purchase completion screen according to an embodiment of the present invention. [Figure 17] This figure shows an example of a sequence relating to the asset information rewriting process according to an embodiment of the present invention. [Figure 18] This figure shows an example of transaction details information according to an embodiment of the present invention. [Figure 19] This figure shows an example of seller information according to an embodiment of the present invention. [Figure 20] This figure shows an example of transaction history information according to an embodiment of the present invention. [Figure 21] This figure shows an example of transaction information and asset information according to an embodiment of the present invention. [Figure 22] This figure shows an example of a sequence relating to the processing of payment for purchased electricity according to an embodiment of the present invention. [Figure 23] It is a diagram showing an example of a payment fee notification screen according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of a transaction system, a node, a blockchain network, a processing method, and a program according to the present invention will be described in detail with reference to the accompanying drawings.

[0009] [First Embodiment] <System Overview> FIG. 1 is a diagram showing an example of a schematic diagram of a transaction system according to an embodiment of the present invention. Here, power is handled as an example of an asset handled by a blockchain network. In the transaction system 1, a user who purchases and uses power is called a user, and a merchant who sells power to the user is called a seller. A user may also be called a purchaser or a consumer, and a seller may also be called a retailer. The transaction system 1 has, for example, an information terminal 4, a charging device 3, an intermediary system 6, a node 9, a transaction server 5, and a terminal device 7 connected to a communication network 100 such as the Internet, a mobile communication network, and a local network.

[0010] The information terminal 4 is a smartphone or a tablet terminal operated by the user, and connects to the transaction server 5 when newly registering user information.

[0011] The charging device 3 supplies (charges) power to an electric vehicle 8 or the like based on the operation of the user, measures the amount of power supplied like a smart meter, and stores the amount of power for each use by the user. Further, the charging device 3 transmits information related to the power transaction including the amount of power used by the user, the unique supply location number assigned to each charging device 3 indicating the location where the power is used, and information related to the destination of the power (for example, the vehicle registration number of the electric vehicle 8) to the information terminal 4, the transaction server 5, and the intermediary system 6.

[0012] The transaction server 5 performs new user registration by storing information about the user as user information 58 based on a new user registration request received from the information terminal 4. The transaction server 5 also receives information about the amount of electricity used by the user from the charging device 3, calculates the charge for the amount of electricity used, and transmits the calculated charge information to the charging device 3. Furthermore, the transaction server 5, in response to a payment processing request received from the terminal device 7 operated by the electricity seller, calculates the payment amount for the specified usage period for the specified user based on the transaction information obtained from node 9 via the intermediary system 6. In addition, the transaction server 5 executes the process of deducting the calculated payment amount from the bank account of the user who used the electricity.

[0013] The intermediary system 6 stores information related to electricity transactions, including the amount of electricity used by the user, received from the charging device 3, and then transmits the received information to node 9. Furthermore, based on a request for transaction information retrieval received from the transaction server 5, the intermediary system 6 requests transaction information and asset information from node 9 and transmits the received information to the transaction server 5. The intermediary system 6 stores buyer information 65, seller information 66, transaction details information 67, and transaction history information 68. Details of the stored information will be described later.

[0014] Node 9, based on requests from the intermediary system 6, rewrites asset information related to electricity handled by the blockchain network 105, and reads transaction information and asset information. Node 9 is constructed from nodes 9a, 9b, 9c, and 9d, which are computers, etc. Although there are actually many nodes 9a, 9b, 9c, and 9d, only four are shown here for space limitations. Nodes 9a, 9b, 9c, and 9d are each managed by different companies, etc. Hereafter, nodes 9a, 9b, 9c, and 9d will be collectively referred to as Node 9.

[0015] Terminal device 7 is a laptop computer or similar device operated by the electricity seller (retailer), and based on the seller's operations, it sends a request to the transaction server 5 for payment processing for users who have used electricity.

[0016] Note that the system configuration of trading system 1 shown in Figure 1 is just one example. For example, the communication network 100 may include, for example, a mobile communication system (4G, 5G, 6G, etc.) or a wireless communication network such as WiMAX (Worldwide Interoperability for Microwave Access). Also, the information terminal 4 is not limited to a smartphone, but may also be a smartwatch, PC (Personal Computer), smart glasses, etc. Furthermore, the trading server 5 may be included in the intermediary system 6. Also, the charging device 3 and smart meter may be called power measurement devices.

[0017] The dotted lines S101, S102, S103, and S104 in Figure 1 show the data flow in four processes related to electricity trading executed in the trading system 1, and these processes are executed in the order shown in the flowchart in Figure 2. Figure 2 is a diagram showing an example of a flowchart relating to the processing of electricity trading according to an embodiment of the present invention. First, in step S101, the trading system 1 executes a new user information registration process to register information about a user who purchases and uses electricity. Next, in step S102, the trading system 1 executes an electricity purchase process in which the user purchases electricity. In step S103, the trading system 1 executes an asset information rewriting process to rewrite the asset information stored in node 9. Finally, in step S104, the trading system 1 executes a purchased electricity payment process to deduct the payment for the electricity used by the user from the user's bank account.

[0018] <Example Hardware Configuration (Information Terminal 4)> Figure 3 shows an example of the hardware configuration of an information terminal 4 according to an embodiment of the present invention. As shown in Figure 3, the information terminal 4 includes a CPU 401, ROM 402, RAM 403, EEPROM 404, CMOS sensor 405, image sensor I / F 406, acceleration / direction sensor 407, media I / F 409, and GPS receiver 411.

[0019] Of these, the CPU 401 controls the operation of the entire information terminal 4. The ROM 402 stores programs used to drive the CPU 401, such as the CPU 401 and IPL. The RAM 403 is used as the work area for the CPU 401. The EEPROM 404 reads or writes various data, such as information terminal programs, according to the control of the CPU 401. The CMOS (Complementary Metal Oxide Semiconductor) sensor 405 is a type of built-in imaging means that captures an image of a subject (mainly a self-portrait) according to the control of the CPU 401 to obtain image data. Note that it may be an imaging means such as a CCD (Charge Coupled Device) sensor instead of a CMOS sensor. The image sensor I / F 406 is a circuit that controls the driving of the CMOS sensor 405. The acceleration / direction sensor 407 is a type of sensor such as an electronic magnetic compass, gyrocompass, or acceleration sensor that detects the Earth's magnetic field. The media I / F 409 controls the reading or writing (storage) of data to or from the recording medium 408, such as flash memory. The GPS receiver 411 receives GPS signals from GPS satellites.

[0020] Furthermore, the information terminal 4 is equipped with a long-range communication circuit 412, a CMOS sensor 413, an image sensor interface 414, a microphone 415, a speaker 416, an audio input / output interface 417, a display 418, an external device connection interface 419, a short-range communication circuit 420, an antenna 420a for the short-range communication circuit 420, and a touch panel 421.

[0021] Of these, the long-range communication circuit 412 is a circuit that communicates with other devices via the communication network 100. The CMOS sensor 413 is a type of built-in imaging means that captures an image of a subject and obtains image data according to the control of the CPU 401. The image sensor interface 414 is a circuit that controls the driving of the CMOS sensor 413. The microphone 415 is a built-in circuit that converts sound into electrical signals. The speaker 416 is a built-in circuit that converts electrical signals into physical vibrations to produce sound such as music and speech. The sound input / output interface 417 is a circuit that processes the input and output of sound signals between the microphone 415 and the speaker 416 according to the control of the CPU 401. The display 418 is a type of display means such as liquid crystal or organic EL (electroluminescence) that displays images of the subject and various icons. The external device connection interface 419 is an interface for connecting various external devices. The short-range communication circuit 420 is a communication circuit such as NFC (Near Field Communication) or Bluetooth (registered trademark). The touch panel 421 is a type of input means that allows the user to operate the information terminal 4 by pressing the display 418.

[0022] Furthermore, the information terminal 4 is equipped with a bus line 410. The bus line 410 is an address bus, data bus, etc., for electrically connecting each component, such as the CPU 401 shown in Figure 3.

[0023] <Example Hardware Configuration (5 Trading Servers, 6 Intermediary Systems, 7 Terminal Devices, 9 Nodes)> Figure 4 shows an example of the hardware configuration of an information processing device that constitutes a transaction server 5, an intermediary system 6, a terminal device 7, and a node 9 according to an embodiment of the present invention. As shown in Figure 4, the information processing device is built by a computer and includes a CPU 501, ROM 502, RAM 503, HD (Hard Disk) 504, HDD (Hard Disk Drive) controller 505, display 506, external device connection I / F (Interface) 508, network I / F 509, bus line 510, keyboard 511, pointing device 512, DVD-RW (Digital Versatile Disk Rewritable) drive 514, and media I / F 516.

[0024] Of these, the CPU 501 controls the operation of the entire information processing unit. The ROM 502 stores programs used to drive the CPU 501, such as IPL. The RAM 503 is used as the work area for the CPU 501. The HD 504 stores various data such as programs. The HDD controller 505 controls the reading or writing of various data to the HD 504 according to the control of the CPU 501. The display 506 displays various information such as cursors, menus, windows, characters, or images. The external device connection I / F 508 is an interface for connecting various external devices. In this case, external devices include, for example, USB (Universal Serial Bus) memory and printers. The network I / F 509 is an interface for data communication using the communication network 100. The bus line 510 is an address bus, data bus, etc., for electrically connecting each component such as the CPU 501 shown in Figure 4.

[0025] The keyboard 511 is a type of input means equipped with multiple keys used for inputting characters, numbers, or various instructions. The pointing device 512 is a type of input means used for selecting and executing various instructions, selecting processing targets, moving the cursor, etc. The DVD-RW drive 514 controls the reading or writing of various data to the DVD-RW 513, which is an example of a removable recording medium. Note that the DVD-RW drive 514 is not limited to DVD-RW, but may also be DVD-R, etc. The media I / F 516 controls the reading or writing (storage) of data to the recording medium 515, such as flash memory.

[0026] <Example Hardware Configuration (Charging Device 3)> Figure 5 is a diagram showing an example of the hardware configuration of a charging device 3 according to an embodiment of the present invention. As shown in Figure 5, the charging device 3 is equipped with a computer and includes a CPU 301, ROM 302, RAM 303, NVRAM 304, display 306, measuring sensor 307, switch 308, network I / F 309, keypad 311, touch panel 312, short-range communication circuit 320, and antenna 320a of the short-range communication circuit 320.

[0027] Of these components, the CPU 301 controls the operation of the entire charging device 3. The ROM 302 stores programs used to drive the CPU 301, such as IPL. The RAM 303 is used as the work area for the CPU 301. The NVRAM (Non-Volatile RAM) 304 is a non-volatile memory that stores and reads various data such as programs. The display 306 displays various information such as cursors, menus, windows, characters, or images.

[0028] The measuring sensor 307 measures the power supplied or used. The switch 308 turns the circuit on (closes) or off (opens) to allow or stop electricity from flowing.

[0029] The network interface 309 is an interface for data communication using a communication network 100, such as the Internet, including the blockchain network 105. The keypad 311 is a type of input means equipped with multiple keys for inputting or selecting characters, numbers, and various instructions. The short-range communication circuit 320 is a communication circuit that realizes short-range wireless technologies such as NFC and Bluetooth (registered trademark). The bus line 310 is an address bus, data bus, etc., for electrically connecting each component, such as the CPU 301 shown in Figure 5.

[0030] <About the features> Figure 6 is a diagram showing an example of the configuration of a functional block in a trading system 1 according to an embodiment of the present invention.

[0031] The information terminal 4 includes a communication unit 40, an operation reception unit 41, and a display control unit 42. Each of these units is a function or means realized by the CPU 401 executing instructions contained in one or more programs installed on the information terminal 4. The storage unit 49 can be realized, for example, by a storage device constructed from the ROM 202, RAM 203, and EEPROM 204 of the information terminal 4.

[0032] The communication unit 40 is a communication function of the information terminal 4, and it sends and receives information with the charging device 3, the transaction server 5, and the terminal device 7, etc., via the communication network 100. For example, the communication unit 40 sends newly registered user information to the transaction server 5. The communication unit 40 also receives information regarding electricity payment charges from the transaction server 5 and the terminal device 7.

[0033] The operation reception unit 41 receives user operations such as text input and button presses via the touch panel 421 of the information terminal 4.

[0034] The display control unit 42 uses the received screen information to display the login screen, electricity payment screen, etc., on the display 418 of the information terminal 4.

[0035] The memory unit 49 stores, for example, information regarding electricity payment charges received by the communication unit 40.

[0036] The charging device 3 includes a communication unit 30, an operation reception unit 31, a display control unit 32, and a measurement unit 34. Each of these units is a function or means realized by the CPU 301 executing instructions included in one or more programs installed in the charging device 3. The storage unit 39 can be realized by a storage device constructed from, for example, a ROM 302, RAM 303, and NVRAM 304 in the charging device 3. The charging device 3 may also be configured without an operation reception unit 31, as the communication unit 30 receives information about user operations from the information terminal 4. Here, communication between the charging device 3 and the information terminal 4 may be direct terminal-to-terminal communication using short-range communication technology such as Bluetooth®.

[0037] The communication unit 30 is a communication function of the charging device 3, and it sends and receives information with the information terminal 4, the transaction server 5, and the intermediary system 6 via the communication network 100. For example, the communication unit 40 transmits the user ID of the power purchaser, the supply point number assigned to the charging device 3, and information on where the power is used to the intermediary system 6. Here, the user ID is an identifier used to identify the user, and ID is an abbreviation for Identification.

[0038] The operation reception unit 31 receives user operations such as text input and button presses via the keypad 311 of the charging device 3.

[0039] The display control unit 32 uses the received screen information to display the login screen, the electricity payment screen, etc., on the display 306 of the charging device 3.

[0040] The measurement unit 34 measures the amount of electrical energy charged by the charging device 3.

[0041] The memory unit 39 stores information such as the destination of power consumption entered by the user.

[0042] The trading server 5 includes a communication unit 50, a display control unit 52, an authentication unit 53, a calculation unit 54, and a processing unit 55. Each of these units is a function or means realized by the CPU 501 executing instructions contained in one or more programs installed on the trading server 5. The storage unit 59 can be realized, for example, by a storage device constructed from the ROM 502 and HDD 504 of the trading server 5.

[0043] The communication unit 50 is a communication function of the transaction server 5, and it transmits and receives information with the charging device 3, information terminal 4, intermediary system 6, and terminal device 7 via the communication network 100.

[0044] The display control unit 52 creates screen information for displaying, for example, a login screen, a power purchase screen, and a payment fee screen on the information terminal 4. Here, the screen information may be information for the information terminal 4 to display using a web browser, or it may be information for the information terminal 4 to display using an application installed on the information terminal 4.

[0045] The authentication unit 53 uses user authentication information (user ID and password) to perform user authentication for users logging into the transaction server 5.

[0046] The calculation unit 54 calculates the electricity payment based on the amount of electricity used (or purchased) by the user and the unit price of electricity.

[0047] The processing unit 55 executes the process of debiting the payment amount calculated by the calculation unit 54 from the purchaser's bank account. The processing unit 55 also creates payment amount notification screen information and receipts based on the payment amount calculated by the calculation unit 54.

[0048] The memory unit 59 stores the user information 58 of the user in the trading system 1. Details of the user information 58 will be described later.

[0049] The intermediary system 6 includes a communication unit 60, a reading unit 63, and a determination unit 64. Each of these units is a function or means realized by the CPU 501 executing instructions contained in one or more programs installed in the intermediary system 6. The storage unit 69 can be realized, for example, by a storage device constructed from the ROM 502 and HDD 504 of the intermediary system 6.

[0050] The communication unit 60 is a communication function of the intermediary system 6, and it transmits and receives information with the charging device 3, information terminal 4, and transaction server 5 via the communication network 100.

[0051] The reading unit 63 reads out the transaction details information 67 and the transaction history information 68 stored in the storage unit 69.

[0052] The decision unit 64 determines the production method of the asset related to the asset information to be transferred to the buyer, based on the transaction details information 67 and the transaction history information 68.

[0053] The memory unit 69 stores buyer information 65, seller information 66, transaction details information 67, and transaction history information 68. Details of this information will be described later.

[0054] Node 9 includes a communication unit 90, a verification unit 93, a reading unit 94, and a processing unit 95. Each of these units is a function or means realized by the CPU 501 executing instructions contained in one or more programs installed on Node 9. The storage unit 99 can be realized, for example, by a storage device constructed from a ROM 502 and an HDD 504 provided by the intermediary system 6.

[0055] The communication unit 90 is a communication function of node 9, and it sends and receives information with the intermediary system 6 via the communication network 100. For example, the communication unit 90 receives the user ID of the power purchaser, the supply point number assigned to the charging device 3, and information on where the power is used from the intermediary system 6.

[0056] The verification unit 93 verifies the certificate of the intermediary system 6 in order to confirm that the intermediary system 6, which is the communication partner, is not a system that is impersonating the intermediary system 6. The verification unit 93 also verifies the legitimacy of the information received from the intermediary system 6 by, for example, determining whether the received information is in a predetermined format and content.

[0057] The reading unit 94, in response to a request from the intermediary system 6, extracts and reads all of the transaction information and asset information managed by the intermediary system 6, or information corresponding to a specified transaction period for a specified user. Details of the reading method will be described later.

[0058] The processing unit 95 rewrites the asset information in response to a request from the intermediary system 6.

[0059] The memory unit 99 stores transaction information and asset information. Details of transaction information and asset information will be described later.

[0060] The terminal device 7 includes a communication unit 70, an operation reception unit 71, and a display control unit 72. Each of these units is a function or means realized by the CPU 501 executing instructions contained in one or more programs installed in the terminal device 7. The storage unit 79 can be realized, for example, by a storage device constructed from the ROM 502 and HDD 504 of the terminal device 7.

[0061] The communication unit 70 is a communication function of the terminal device 7, and it sends and receives information with the information terminal 4 and the transaction server 5 via the communication network 100. For example, the communication unit 70 receives information regarding electricity payment charges from the transaction server 5.

[0062] The operation reception unit 71 receives user operations such as character input and button presses via the keyboard 511 and pointing device 512 of the terminal device 7.

[0063] The display control unit 72 uses the received screen information to display a login screen or the like on the display 506 of the terminal device 7.

[0064] The memory unit 79 stores, for example, information regarding electricity payment charges received by the communication unit 70.

[0065] Hereafter, we will explain each of the steps S101 to S104 in the power trading process shown in Figure 2 in order.

[0066] <User Information New Registration Process> Figure 7 shows an example of a sequence of steps relating to the process of registering new user information according to an embodiment of the present invention. In this sequence, the process of registering new user information of a user using the trading system 1 to the trading server 5 is executed. The process of each step in Figure 7 will be described below.

[0067] Step S200: The operation reception unit 41 of the information terminal 4 receives an operation from the user to access the trading server 5. The user may perform the operation using a terminal device 7 such as a laptop computer instead of the information terminal 4 such as a smartphone. The communication unit 40 of the information terminal 4 sends a login screen display request to the communication unit 50 of the trading server 5.

[0068] Step S201: The communication unit 50 of the trading server 5 receives a login screen display request from the communication unit 40 of the information terminal 4. In response to the login screen display request received by the communication unit 50, the display control unit 52 of the trading server 5 creates login screen information to display the login screen on the information terminal 4.

[0069] Step S202: The communication unit 50 of the transaction server 5 transmits the login screen information created by the display control unit 52 to the communication unit 40 of the information terminal 4.

[0070] Step S203: The communication unit 40 of the information terminal 4 receives login screen information from the communication unit 50 of the transaction server 5. The display control unit 42 of the information terminal 4 displays the login screen on the information terminal 4 based on the login screen information received by the communication unit 40. Figure 8 is a diagram showing an example of a login screen according to an embodiment of the present invention. The login screen 145 in Figure 8 has a user ID input field 146, a password input field 147, a login button 148, and a new user information registration request button 180. The user presses the new user information registration request button 180 to register new user information. The operation reception unit 41 of the information terminal 4 receives the operation by the user to press the new user information registration request button 180. Let's return to Figure 7 for explanation.

[0071] Step S204: The communication unit 40 of the information terminal 4 sends a request to display the user information registration screen to the communication unit 50 of the transaction server 5.

[0072] Step S205: The communication unit 50 of the trading server 5 receives a user information registration screen display request from the communication unit 40 of the information terminal 4. In response to the user information registration screen display request received by the communication unit 50, the display control unit 52 of the trading server 5 creates user information registration screen information to display the user information registration screen on the information terminal 4.

[0073] Step S206: The communication unit 50 of the transaction server 5 transmits the user information registration screen information created by the display control unit 52 to the communication unit 40 of the information terminal 4.

[0074] Step S207: The communication unit 40 of the information terminal 4 receives user information registration screen information from the communication unit 50 of the transaction server 5. The display control unit 42 of the information terminal 4 displays the user information registration screen on the information terminal 4 based on the user information registration screen information received by the communication unit 40. Figure 9 is a diagram showing an example of a user information registration screen according to an embodiment of the present invention. The user information registration screen 149 in Figure 9 has input fields for entering various information about the user, an OK button 160, and a Cancel button 161. The name input field 150, user ID input field 151, password input field 152, postal code input field 153, address input field 154, telephone number input field 155, and email address input field 156 are for entering the user's name, user ID, password, postal code, address, telephone number, and email address, respectively. Here, the user ID is an identifier for identifying the user, and ID is an abbreviation for Identification. In the supply point number input field 157, for example, the supply point number assigned to the charging device 3 (smart meter) set up at the user's home is entered. The renewable energy utilization rate selection field 158 is for the user to select the percentage of renewable energy in the electricity they use. In this example, 30% and 100% can be specified. Renewable energy includes, for example, electricity produced from solar power, solar thermal energy, wind power, biomass, geothermal energy, hydropower, and heat from the atmosphere. This utilization rate may be used if the user does not specify a utilization rate when purchasing electricity. The bank account information input field 159 is for the user to input information about the bank account from which electricity charges will be paid (debited). It has fields for the name of the financial institution, branch name, account type (savings, checking, etc.), account number, and account holder name. After the user has entered all the information, they press the OK button 160. The operation reception unit 41 of the information terminal 4 accepts the user's operation to input various information and then accepts the operation to press the OK button 160. Let's return to Figure 7 for explanation.

[0075] Step S208: The communication unit 40 of the information terminal 4 transmits the newly registered user information (new user information) entered by the user to the communication unit 50 of the transaction server 5.

[0076] Step S209: The communication unit 50 of the transaction server 5 receives new user information from the communication unit 40 of the information terminal 4. The storage unit 59 of the transaction server 5 registers the new user information as user information 58 based on the new user information received by the communication unit 50. Figure 10 is a diagram showing an example of user information according to an embodiment of the present invention. In the user information 58 of Figure 10, the items name 110, postal code 111, address 112, telephone number 113, email address 114, user ID 115, password 116, supply point number 117, renewable energy utilization rate 118, and bank account information 120 are set with the corresponding items in the new user information received by the communication unit 50. In the item electricity unit price 119, a predetermined charge is set for 1 kWh of electricity (the amount of electricity when 1 kilowatt of electricity is used for 1 hour). The charge may be set according to the renewable energy utilization rate, etc., or a flat rate may be set. The storage unit 59 of the trading server 5 registers user information by storing user information 58 in the storage device of the trading server 5. Let's return to Figure 7 for further explanation.

[0077] Step S210: The communication unit 50 of the transaction server 5 sends a buyer information registration request to the communication unit 60 of the intermediary system 6. The buyer information registration request includes information regarding the user ID, name, and address of the new user in order to register the new user information as buyer information.

[0078] Step S211: The communication unit 60 of the intermediary system 6 receives a buyer information registration request from the communication unit 50 of the transaction server 5. The storage unit 69 of the intermediary system 6 registers the buyer information using the information regarding the user ID, name, and address received by the communication unit 60. Figure 11 is a diagram showing an example of buyer information according to an embodiment of the present invention. The buyer information 65 in Figure 11 has the fields of buyer ID 122, name 123, and address 124. The storage unit 69 registers the buyer information by setting the information regarding the user ID, name, and address received by the communication unit 60 into the fields of buyer ID 122, name 123, and address 124 of the buyer information 65, respectively, and storing it in the storage device of the intermediary system 6. Let's return to Figure 7 for further explanation.

[0079] Step S212: The communication unit 60 of the intermediary system 6 sends a notification of completion of buyer information registration to the communication unit 50 of the transaction server 5.

[0080] Step S213: The communication unit 50 of the transaction server 5 receives a notification from the communication unit 60 of the intermediary system 6 that the buyer information registration is complete. The display control unit 52 of the transaction server 5 creates user information registration completion screen information to display the user information registration completion screen on the information terminal 4.

[0081] Step S214: The communication unit 50 of the transaction server 5 transmits the user information registration completion screen information created by the display control unit 52 to the communication unit 40 of the information terminal 4.

[0082] Step S215: The communication unit 40 of the information terminal 4 receives user information registration completion screen information from the communication unit 50 of the transaction server 5. The display control unit 42 of the information terminal 4 displays the user information registration completion screen on the information terminal 4 based on the user information registration completion screen information received by the communication unit 40. Figure 12 is a diagram showing an example of a user information registration completion screen according to an embodiment of the present invention. The user information registration completion screen 162 in Figure 12 displays the message "User information registration is complete" and a button 163 to be pressed when returning to the login screen.

[0083] Through the above process, the user information of the new user is registered in the trading server 5 in trading system 1.

[0084] <Electricity Purchase Processing> Figure 13 shows an example of a sequence of steps relating to the process of registering purchased electricity according to an embodiment of the present invention. In this sequence, in the trading system 1, the user purchases electricity by operating the charging device 3 (smart meter), and the purchased electricity is used to charge the electric vehicle 8. The processing of each step in Figure 13 will be described below.

[0085] Step S220: The operation reception unit 31 of the charging device 3 accepts an operation from the user to access the trading server 5. The communication unit 30 of the charging device 3 sends a login screen display request to the communication unit 50 of the trading server 5.

[0086] Step S221: The communication unit 50 of the trading server 5 receives a login screen display request from the communication unit 30 of the charging device 3. In response to the login screen display request received by the communication unit 50, the display control unit 52 of the trading server 5 creates login screen information to display the login screen on the charging device 3.

[0087] Step S222: The communication unit 50 of the transaction server 5 transmits the login screen information created by the display control unit 52 to the communication unit 30 of the charging device 3.

[0088] Step S223: The communication unit 30 of the charging device 3 receives login screen information from the communication unit 50 of the transaction server 5. The display control unit 32 of the charging device 3 displays the login screen on the charging device 3 based on the login screen information received by the communication unit 30. The login screen to be displayed is the same as the login screen 145 shown in Figure 8. The user enters their user ID and password in the user ID input field 146 and password input field 147, respectively, and then presses the login button 148. The operation reception unit 31 of the charging device 3 receives the user's operation to enter their user ID and password, and then receives the operation to press the login button 148.

[0089] Step S224: The communication unit 30 of the charging device 3 sends the user ID and password entered by the user, which are the user authentication information required when logging in, to the communication unit 50 of the transaction server 5.

[0090] Step S225: The communication unit 50 of the trading server 5 receives user authentication information (user ID and password) from the communication unit 30 of the charging device 3. The authentication unit 53 of the trading server 5 performs user authentication using the user authentication information received by the communication unit 50. The authentication unit 53 determines that user authentication is successful if the user information 58 stored in the storage unit 59 of the trading server 5 contains authentication information that matches the received authentication information.

[0091] Step S226: After successful user authentication, the display control unit 52 of the transaction server 5 creates power purchase screen information to display the power purchase screen on the charging device 3.

[0092] Step S227: The communication unit 50 of the transaction server 5 transmits the power purchase screen information created by the display control unit 52 to the communication unit 30 of the charging device 3.

[0093] Step S228: The communication unit 30 of the charging device 3 receives power purchase screen information from the communication unit 50 of the transaction server 5. The display control unit 32 of the charging device 3 displays the power purchase screen on the charging device 3 based on the power purchase screen information received by the communication unit 30. Figure 14 is a diagram showing an example of a power purchase screen according to an embodiment of the present invention. The power purchase screen 164 in Figure 14 has a planned usage amount input field 165, a renewable energy utilization rate input field 166, an OK button 167, and a cancel button 168. The planned usage amount input field 165 is a field for entering the amount of electricity to be purchased. The renewable energy utilization rate input field 166 is a field for entering the renewable energy utilization rate of the electricity to be purchased. The OK button 167 is a button to press when confirming the entered information. The cancel button 168 is a button to press when canceling the purchase of electricity. The operation reception unit 31 of the charging device 3 accepts the user's input of the planned amount of electricity to be purchased and the renewable energy utilization rate of the purchased electricity, and then accepts the user's input of the OK button 167. Let's return to Figure 13 for further explanation.

[0094] Step S229: The communication unit 30 of the charging device 3 transmits the information regarding the purchase of electricity (electricity purchase information) entered by the user to the communication unit 50 of the transaction server 5. The electricity purchase information includes information regarding the amount of electricity to be purchased by the user.

[0095] Step S230: The calculation unit 54 of the transaction server 5 calculates the amount of electricity to be paid by the user (payment amount) based on the amount of electricity used included in the electricity purchase information received by the communication unit 50 and the electricity unit price 119 in the user information 58 stored in the storage unit 59. For example, if the amount of electricity used is 400kWh, the renewable energy utilization rate is 30%, the electricity unit price for renewable energy is 35 yen, and the electricity unit price for non-renewable energy is 30 yen, the payment amount will be 400 × 0.3 × 35 + 400 × 0.7 × 30 = 12,600 yen.

[0096] Step S231: The display control unit 52 of the transaction server 5 creates payment fee screen information for displaying the payment fee screen on the charging device 3.

[0097] Step S232: The communication unit 50 of the transaction server 5 transmits the payment fee screen information created by the display control unit 52 to the communication unit 30 of the charging device 3.

[0098] Step S233: The communication unit 30 of the charging device 3 receives payment fee screen information from the communication unit 50 of the transaction server 5. The display control unit 32 of the charging device 3 displays the payment fee screen on the charging device 3 based on the payment fee screen information received by the communication unit 30. Figure 15 is a diagram showing an example of a payment fee calculation result screen according to an embodiment of the present invention. The payment fee screen 169 in Figure 15 shows that the payment fee for 400 kWh of electricity is 12,600 yen. The payment fee screen 169 also has a vehicle registration number input field 170, an OK button 171, and a cancel button 172. The user enters the vehicle registration number in the vehicle registration number input field 170 as information about where the electricity will be used. The OK button 171 is a button to press when confirming the entered information. The cancel button 172 is a button to press when canceling the purchase of electricity. After the operation reception unit 31 of the charging device 3 receives the operation of the user to enter the vehicle registration number, it receives the operation of pressing the OK button 171.

[0099] Step S234: The communication unit 30 of the charging device 3 sends a power purchase request to the communication unit 50 of the trading server 5.

[0100] Step S235: The storage unit 39 of the charging device 3 stores the vehicle registration number, which is information about where the power will be used, entered by the user, in the storage device of the charging device 3.

[0101] Step S236: The display control unit 32 of the charging device 3 displays a purchase completion screen, and the charging device 3 starts charging the electric vehicle 8. The measurement unit 34 of the charging device 3 measures the amount of electricity being charged. Figure 16 is a diagram showing an example of a purchase completion screen according to an embodiment of the present invention. The purchase completion screen 173 in Figure 16 displays a message notifying that the purchase of 400 kWh of electricity has been completed and charging has started. The purchase completion screen 173 also has a button 174 to be pressed when returning to the login screen.

[0102] Through the above process, the purchase of electricity is executed in trading system 1. In this sequence, an example was shown in which the user enters the vehicle registration number as the electricity usage information, but the usage information may be obtained by other means. For example, a camera for photographing the vehicle registration plate (license plate) may be installed near where the electric vehicle 8 is parked, and the charging device 3 may obtain the image of the license plate taken by the camera as usage information. Alternatively, photographs of the electric vehicle being charged or the equipment using the electricity may be used as usage information to identify or confirm how the electricity was used. In the sequence shown in Figure 13, the user may operate an information terminal 4 that communicates with the charging device 3, and the information terminal 4 may transmit information about the user's operation to the charging device 3. At this time, the charging device 3 transmits screen information such as the login screen and payment fee screen received from the transaction server 5 to the information terminal 4. The information terminal 4 uses the received screen information to display the login screen, payment fee screen, etc., on the display 418 of the information terminal 4.

[0103] <Asset Information Rewriting Process> Figure 17 shows an example sequence of asset information rewriting processing according to an embodiment of the present invention. In this sequence, the trading system 1 performs asset information rewriting processing based on information about the electricity used, which is stored in node 9. The asset information rewriting processing is performed, for example, at predetermined time intervals (e.g., every 30 minutes) at home, and outside the home, after purchasing electricity to charge the electric vehicle 8. The processing of each step in Figure 17 will be described below.

[0104] Step S240: The communication unit 30 of the charging device 3 transmits power usage information to the communication unit 60 of the intermediary system 6 in order to rewrite the asset information stored in node 9. The power usage information includes the user ID of the user who used the power, the amount of power used (kWh), the date and time of power use, the supply point number assigned to the charging device 3, and information on where the power was used.

[0105] Step S241: The communication unit 60 of the intermediary system 6 receives power usage information from the communication unit 30 of the charging device 3. The communication unit 60 of the intermediary system 6 sends an asset information acquisition request to the communication unit 90 of node 9. The asset information acquisition request includes an electronic certificate to prove the legitimacy of the intermediary system 6. The certificate can be, for example, a certificate from a Public Key Infrastructure (PKI).

[0106] Step S242: The communication unit 90 of node 9 receives an asset information acquisition request from the communication unit 60 of the intermediary system 6. The verification unit 93 of node 9 verifies the certificate of the intermediary system 6 included in the asset information acquisition request. For example, a general public key cryptography authentication method can be used for verification. Here, we assume that the verification was successful and proceed to the next step.

[0107] Step S243: The read unit 94 of node 9 reads all asset information managed by the intermediary system 6.

[0108] Step S244: The communication unit 90 of node 9 transmits the asset information read by the reading unit 94 to the communication unit 60 of the intermediary system 6.

[0109] Step S245: The communication unit 60 of the intermediary system 6 receives asset information from the communication unit 90 of node 9. The reading unit 63 of the intermediary system 6 reads the transaction details information 67 stored in the storage unit 69 of the intermediary system 6. Figure 18 is a diagram showing an example of transaction details information 67 according to an embodiment of the present invention. The transaction details information 67 in Figure 18 has the following items: purchaser ID 131, start date of use 132, end date of use 133, planned usage amount 134, renewable energy utilization rate 135, seller ID 136, seller name 137, and production method 138. The purchaser ID 131 is the user ID of the purchaser who purchased the electricity. Information about the purchaser is managed in the purchaser information 65 in Figure 11. The start date of use 132 is the date on which the use of the asset (electricity) begins. The end date of use 133 is the date on which the use of the asset (electricity) ends. The planned usage amount 134 is the amount of assets (electricity (kWh)) that the user plans to use over a certain period (or for a certain amount of time). The renewable energy utilization rate 135 is the percentage (%) of assets such as electricity used by the user that are produced using renewable energy such as solar power. The seller ID 136 is an identifier that identifies the seller who sold the electricity purchased by the buyer. The seller name 137 is the name of the seller who sold the electricity purchased by the buyer. The production method 138 is the type of energy used to produce the electricity, which is an asset. Examples of production methods include methods that use solar power, wind power, biomass, geothermal energy, hydropower, petroleum, coal, and liquefied natural gas. The production method may also be indicated by a broad category such as renewable energy or fossil fuels. Here, the storage unit 69 of the intermediary system 6 stores information about the seller. Figure 19 is a diagram showing an example of seller information 66 according to an embodiment of the present invention. The seller information 66 in Figure 19 includes the following items: seller ID 126, seller name 127, production method 128, and available quantity 129. The seller ID 126 is the user ID of the seller (retailer) selling the electricity. The seller name 127 is the seller's name. The production method 128 is the type of energy used to produce the electricity, as explained in production method 138 in Figure 18. The available quantity 129 is the amount of electricity (kWh) that can be supplied over a certain period (or time). Let's return to Figure 17 for further explanation.

[0110] Step S246: The reading unit 63 of the intermediary system 6 reads the transaction history information 68 stored in the storage unit 69 of the intermediary system 6. Figure 20 is a diagram showing an example of transaction history information 68 according to an embodiment of the present invention. The transaction history information 68 in Figure 20 has the following items: intermediary date and time 140, transaction amount 141, production method 142, total transaction amount by solar power 143, and total transaction amount by petroleum 144. The intermediary date and time 140 is the date and time when the intermediary system 6 intermediaries the ownership of an asset (electricity) by assigning ownership of the asset from the seller to the buyer. The transaction amount 141 is the transaction amount of the asset that the intermediary system 6 acquires from the seller and intermediaries the transaction of to the buyer, and is shown, for example, in terms of electricity (kWh). The production method 142 is the type of energy used to produce electricity, as explained in the production method 138 of Figure 18. The total transaction volume of solar power (143) and the total transaction volume of oil (144) represent the total amount of assets (electricity) produced by solar power and oil, respectively, allocated to purchasers who are users of electricity over a certain period (or time). The reading unit 63 of the intermediary system 6 reads 20 kWh as the total transaction volume of solar power (143) and 160 kWh as the total transaction volume of oil (144) from the transaction history information 68. Let's return to Figure 17 for further explanation.

[0111] Step S247: The decision unit 64 of the intermediary system 6 determines the production method of the asset related to the asset information to be transferred to the buyer, based on the transaction details information 67 read in step S245 and the transaction history information 68 read in step S246. For example, the transaction details information 67 indicates solar power and oil as production methods, and the transaction history information 68 shows that the latest total transaction quantities are 20kWh for solar power and 160kWh for oil. Therefore, the decision unit 64 determines the production method to be solar power in order to approach the renewable energy rate of 136, which is 40%.

[0112] Step S248: The storage unit 69 of the intermediary system 6 stores transaction history information 68 by adding history information (records) based on the content determined by the decision unit 64 in step S247. For example, the storage unit 69 stores transaction history information 68 with added history information (records) indicating that the intermediary date and time 140 is "2020.1.1 9:00-9:30", the transaction quantity 141 is "10", the production method 142 is "solar power", and the total transaction quantity by solar power 143 is "30".

[0113] Step S249: The communication unit 60 of the intermediary system 6 transmits an asset information change request to the communication unit 90 of node 9. The asset information change request includes an asset ID to identify the asset information relating to a specific asset produced by the specific production method determined in step S247, from among the asset information transmitted in step S244. Furthermore, the asset information change request includes the owner of the new asset (electricity), the amount of asset (electricity) used, the supply point number assigned to the charging device 3, and information on where the electricity will be used. If there are multiple assets produced by the specific production method determined in step 247, the communication unit 60 transmits a change request for the asset whose expiration date is closest to the current date and time from among these multiple assets.

[0114] Step S250: The communication unit 90 of node 9 receives an asset information change request from the communication unit 60 of the mediation system 6. The verification unit 93 of node 9 verifies the information contained in the asset information change request received by the communication unit 90. The verification method is, for example, by determining whether the received information is in a predetermined format and content. Here, it is assumed that the verification was successful, and the process proceeds to the next step.

[0115] Step S251: The processing unit 95 of node 9 generates second transaction information for rewriting asset information identified by the information included in the asset information change request, and adds a block containing the second transaction information to the chain of blocks containing the first transaction stored in the storage unit 99 and stores it. Furthermore, the processing unit 95 rewrites the contents of the asset information according to the second transaction information. Figure 21 is a diagram showing an example of transaction information and asset information according to an embodiment of the present invention. In Figure 21, the first transaction information 190 has a "transaction ID" that identifies the transaction, which is "T0001", and the "transaction type" is set to "asset information generation". Asset information 191 is asset information generated based on the first transaction information 190, and includes information on the items "provider", "date and time of provision", "transactionable energy amount", "production method", "owner", "expiration date", and "transaction status". Also, in asset information 191, the "asset ID" is "A0001", the "expiration date" is "2020.1.31 23:59", and the "transaction status" is "not yet". The second transaction information 192 has the following settings: "Transaction ID" is "T0002", "Transaction Type" is "Rewrite Asset Information", and "Asset ID" is "A0001". Furthermore, the second transaction information 192 has the following settings: "Supply Point Number" is "138289", and "Power Usage Information" is "0123456789". Based on the second transaction information 192, the processing unit 95 of node 9 rewrites the pre-rewrite asset information 191 to the rewritten asset information 193. In asset information 193, the "Transactionable Power Quantity" item is rewritten to the "Power Quantity Used" item, the content of the "Owner" item is changed from "Intermediary Da" to "Consumer Ca", and the content of the "Transaction Status" item is changed from "Not Yet" to "Completed". Furthermore, asset information 193 has additional fields for "supply point number" and "power usage information," with the values ​​"138289" and "0123456789" set, respectively. Let's return to Figure 17 for explanation.

[0116] Step S252: The communication unit 90 of node 9 sends a response to the asset information change request in step S249 to the communication unit 60 of the mediating system 6. This response indicates whether the processing of the asset information change request was successful or unsuccessful.

[0117] Step S253: The communication unit 60 of the mediation system 6 transmits the response received in step S252 to the communication unit 30 of the charging device 3.

[0118] Through the above process, the trading system 1 can rewrite the asset information stored in node 9 based on information about the electricity used (electricity usage information). Here, the electricity usage information and asset information include the supply point number assigned to the charging device 3, which indicates the location where the electricity is used, and information about the destination of the electricity (for example, the vehicle registration number).

[0119] <Payment processing for purchased electricity> Figure 22 shows an example of a sequence of processing for electricity purchase payment according to an embodiment of the present invention. In this sequence, in the transaction system 1, the transaction server 5 calculates the payment amount from the electricity purchaser's usage and debits the payment amount from the purchaser's bank account in response to a request from the electricity seller (retailer). The processing of each step in Figure 22 will be described below.

[0120] Step S260: The operation reception unit 71 of the terminal device 7 receives an operation from the electricity seller (or retailer) to send a payment processing request for electricity to the communication unit 50 of the transaction server 5. The communication unit 70 of the terminal device 7 sends the payment processing request to the communication unit 50 of the transaction server 5. The payment processing request includes a buyer ID to identify the electricity purchaser and information regarding the electricity transaction period.

[0121] Step S261: The communication unit 50 of the transaction server 5 sends a transaction information read request to the communication unit 60 of the intermediary system 6 in response to the payment processing request received in step S260. The transaction information read request includes a purchaser ID to identify the electricity purchaser and information regarding the electricity transaction period.

[0122] Step S262: The communication unit 60 of the intermediary system 6 sends a request to the communication unit 90 of node 9 to retrieve transaction information and asset information in response to the transaction information read request received in step S261. The retrieval request includes a purchaser ID to identify the electricity purchaser and information regarding the electricity transaction period. The retrieval request also includes an electronic certificate to prove the legitimacy of the intermediary system 6. The certificate can be, for example, a certificate from a Public Key Infrastructure (PKI).

[0123] Step S263: The communication unit 90 of node 9 receives a request to acquire transaction information and asset information from the communication unit 60 of the intermediary system 6. The verification unit 93 of node 9 verifies the certificate of the intermediary system 6 included in the acquisition request received by the communication unit 90. For verification, for example, a general public key cryptography authentication method can be used. Here, we assume that the verification was successful and proceed to the next step.

[0124] Step S264: The reading unit 94 of node 9 reads transaction information and asset information corresponding to the buyer ID and information regarding the electricity transaction period included in the acquisition request received by the communication unit 90. For example, the reading unit 94 reads transaction information in which the mediation date and time is within the acquired transaction period and the buyer identified by the acquired buyer ID is set as the owner. Furthermore, the reading unit 94 reads asset information corresponding to the asset ID shown in the read transaction information.

[0125] Step S265: The communication unit 90 of node 9 transmits the transaction information and asset information read by the reading unit 94 in step S264 to the communication unit 60 of the intermediary system 6. The transaction information and asset information to be transmitted include the amount of electricity used during the transaction period, the supply point number indicating the location where the electricity was used, and the destination information for the electricity.

[0126] Step S266: The communication unit 60 of the intermediary system 6 transmits the received transaction information and asset information to the communication unit 50 of the transaction server 5.

[0127] Step S267: The calculation unit 54 of the transaction server 5 calculates the payment charge for the electricity used during the transaction period based on the amount of electricity used during the transaction period and the user information 58 in Figure 10 stored in the storage unit 59 of the transaction server 5. That is, the calculation unit 54 calculates the payment charge for the electricity used during the transaction period by multiplying the amount of electricity used during the transaction period by the electricity unit price 119 corresponding to the purchaser's user ID 116 in the user information 58. For example, if the amount of electricity used during the transaction period is 1000kWh and the electricity unit price 119 is 30 yen / 1kWh, the payment charge will be 1000 × 30 = 30000 yen.

[0128] Step S268: The processing unit 55 of the transaction server 5 executes the process of debiting the payment amount calculated by the calculation unit 54 of the transaction server 5 in step S267 from the buyer's bank account. When executing the process, the processing unit 55 uses the bank account information 120, which corresponds to the buyer's user ID 116 in the user information 58 of Figure 10 and is stored in the storage unit 59 of the transaction server 5, as information related to the bank account.

[0129] Step S269: The processing unit 55 of the transaction server 5 creates notification information and receipts for notifying the payment charges for the electricity used.

[0130] Step S270: The communication unit 50 of the transaction server 5 transmits notification information to the communication unit 70 of the terminal device 7, indicating that the payment processing for electricity has been completed. Figure 23 is a diagram showing an example of a payment notification screen according to an embodiment of the present invention. The payment screen 175 in Figure 23 includes usage period 176, name 177, amount of electricity used 178, payment amount 179, and details of electricity used 181. The usage period 176 is the period during which the electricity for which payment was made was used. The name 177 is the name of the user who used the electricity. The amount of electricity used 178 is the amount of electricity used. The payment amount 179 is the total payment amount for the amount of electricity used 178 during the usage period 176. The details of electricity used 181 show the amount of electricity used and payment amount for each supply point number, which is the location where the electricity was used, and the amount of electricity used and payment amount for each vehicle registration number for each supply point number, as detailed information of the amount of electricity used 178. The communication unit 70 of the terminal device 7 or the communication unit 50 of the transaction server 5 may send notification information to the electricity purchaser's email address or the like. The display control unit 32 of the information terminal 4 operated by the purchaser can display the payment fee screen 175 based on the notification information.

[0131] Furthermore, the processing of payment for purchased electricity may not be initiated by a payment processing request from terminal device 7, but rather by transaction server 5 at a predetermined date and time (such as midnight on the last day of the month) for predetermined users and under predetermined transaction period conditions (for example, from the first day to the last day of the month).

[0132] Through the above process, the transaction system 1 can associate and handle electricity transactions using the blockchain network 105, even if the same user uses electricity in different locations. This is because, when a user purchases electricity, the transaction system 1 stores the user's identifier, the amount of electricity used, the location where the electricity was used, and the destination of the electricity in the blockchain network 105.

[0133] Furthermore, in the trading system 1, the trading server 5 can authenticate users using authentication information (login ID and password) when users who purchase electricity operate the charging device 3 and log in to the trading server 5.

[0134] Furthermore, the transaction server 5 can calculate the payment amount for the amount of electricity used received from the charging device 3 and display the calculated payment amount on the charging device 3.

[0135] Furthermore, the blockchain network 105 (or node 9) can extract transaction information regarding the amount of electricity used, the location of electricity use, and the destination of electricity use for a specified user during a specified transaction period, using an identifier that identifies the user. The transaction server 5 can also calculate the payment amount for the amount of electricity used for a specified user during a specified transaction period based on the transaction information extracted by node 9, and display the calculated payment amount on the information terminal 4 operated by the user. In addition, the transaction server 5 can calculate the payment amount for each location of electricity use (e.g., supply point number) and destination of electricity use (e.g., vehicle registration number), and display the calculated payment amount on the information terminal 4 operated by the user.

[0136] Although several embodiments for carrying out the present invention have been described above, the present invention is not limited in any way to these embodiments, and various modifications and substitutions can be made without departing from the spirit of the present invention.

[0137] For example, the example of the functional block configuration diagram in Figure 6 is divided according to its main function to facilitate understanding of the processing performed by the information processing devices constituting the information terminal 4, charging device 3, trading server 5, intermediary system 6, terminal device 7, and node 9 in the trading system 1. The present invention is not limited by the way the processing units are divided or the names of those units. The processing in the trading system 1 can be further divided into many more processing units depending on the processing content. Furthermore, one processing unit can be divided to include even more processing.

[0138] Furthermore, each function of the embodiments described above can be realized by one or more processing circuits. Hereinafter, "processing circuit" as used herein includes processors programmed to execute each function by software, such as processors implemented by electronic circuits, as well as devices such as ASICs (Application Specific Integrated Circuits), DSPs (digital signal processors), FPGAs (field programmable gate arrays), and conventional circuit modules designed to execute each of the functions described above.

[0139] Furthermore, the described apparatus represents only one of several computing environments for carrying out the embodiments disclosed herein. In one embodiment, trading system 1 includes multiple computing devices, such as a server cluster. The multiple computing devices are configured to communicate with each other via any type of communication link, including networks and shared memory, and perform the processes disclosed herein. [Explanation of symbols]

[0140] 1. Trading System 3 Charging device 4. Information terminals 5. Trading Server 6. Intermediary System 7 Terminal devices 8 Electric vehicles Nodes 9, 9a, 9b, 9c, 9d 30, 40, 50, 60, 70, 90 Communications Department 31, 41, 71 Operation reception section 30, 40, 50, 60, 70, 90 Communications Department 32, 42, 52, 72 Display Control Unit 34 Measurement Unit 53 Certification Department 54 Calculation section 55, 95 Processing Unit 63, 94 Reading section 64 Decision Section 93 Verification Department 39, 49, 59, 69, 79, 99 memory section 100 Communication Networks [Prior art documents] [Patent Documents]

[0141] [Patent Document 1] Patent No. 6704985

Claims

1. A trading system comprising a node in a blockchain network, an intermediary system capable of communicating with the node, a trading server capable of communicating with the intermediary system, and at least one power measuring device, The aforementioned intermediary system, A first communication unit transmits to the node an identifier identifying the user purchasing electricity, the amount of electricity used, the location of electricity use, and the destination of electricity use, which are received from the aforementioned power measuring device. Equipped with, The aforementioned node is A storage unit that stores asset information including the identifier, the amount of power used, the location of use, and the destination of use, received from the aforementioned intermediary system, A reading unit that uses the identifier to extract transaction information from the asset information regarding the amount of electricity used, the location of use, and the destination of use for a specified user during a specified transaction period, A second communication unit transmits the transaction information extracted by the reading unit to the intermediary system, Equipped with, The aforementioned trading server, A third communication unit that receives the aforementioned transaction information from the intermediary system, A calculation unit that calculates the first payment fee based on the aforementioned transaction information, A processing unit that performs the payment processing for the first payment fee, A trading system equipped with the following features.

2. The aforementioned trading server, A storage unit that stores authentication information for authenticating the user, When the user logs in to the transaction server, an authentication unit authenticates the user using the authentication information, The transaction system according to claim 1, further comprising the following:

3. The aforementioned trading server, The calculation unit calculates the second payment charge for the amount of electricity used received from the power measuring device, A display control unit that creates first information for displaying the second payment amount, Furthermore, The third communication unit transmits the first information to the power measuring device. The trading system according to claim 1 or claim 2.

4. The aforementioned trading server, The display control unit generates second information for displaying the first payment amount, The transaction system according to claim 3, wherein the third communication unit transmits the second information to an information terminal operated by the user.

5. The aforementioned trading server, The calculation unit calculates the third payment fee for each usage location based on the transaction information. The display control unit generates third information for displaying the third payment amount, The transaction system according to claim 3, wherein the third communication unit transmits the third information to an information terminal operated by the user.

6. The aforementioned trading server, The calculation unit calculates the fourth payment fee for each usage location and each user based on the transaction information. The display control unit generates fourth information for displaying the fourth payment amount, The transaction system according to claim 3, wherein the third communication unit transmits the fourth information to an information terminal operated by the user.

7. A node in a blockchain network, A storage unit that stores asset information including an identifier to identify the user, the amount of electricity used, the location where the electricity is used, and the destination of the electricity, A reading unit that uses the identifier to extract the amount of electricity used, the location of use, and the destination of use for a specified user during a specified transaction period from the asset information, A node equipped with this feature.

8. A blockchain network characterized by storing asset information including an identifier that identifies a user, the amount of electricity used, the location where the electricity is used, and the destination where the electricity is used, and using the identifier to extract the amount of electricity used, the location where the electricity is used, and the destination for a specified user during a specified transaction period from the asset information.

9. A method of processing performed by a node in a blockchain network, A step of storing asset information including an identifier that identifies the user, the amount of electricity used, the location where the electricity is used, and the destination of the electricity, Using the identifier, the steps include extracting the amount of electricity used, the location of use, and the destination of use for a specified user during a specified transaction period from the asset information, A processing method comprising the following:

10. Nodes in a blockchain network A step of storing asset information including an identifier that identifies the user, the amount of electricity used, the location where the electricity is used, and the destination of the electricity, Using the identifier, the steps include extracting the amount of electricity used, the location of use, and the destination of use for a specified user during a specified transaction period from the asset information. A program that executes the command.

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