Power demand adjustment server and power demand adjustment system using pumped-storage hydroelectric power.

Abstract

To provide a power demand adjustment server and a power demand adjustment system using pumped storage power generation that determine whether to operate a pumped storage power generation device when a request for power demand adjustment is received.SOLUTION: A power demand adjustment server 20 includes an acquisition unit 30 that acquires a per-unit remuneration corresponding to the adjustment of power demand and a current per-unit electricity rate when adjusting the power demand to increase, a calculation unit 32 that calculates an expected value of pumped storage power generation when water is pumped up to the upper reservoir in adjusting the power demand on the basis of the characteristics of the pumped storage power generation device and the per-unit electricity rate at the time of power generation, a determination unit 34 that determines whether to adjust the power demand to increase on the basis of the per-unit remuneration corresponding to the adjustment of power demand, the current per-unit electricity rate, and the expected value of pumped storage power generation, and an output unit 36 that outputs an operation command to the pumped storage power generation device based on the result of the determination by the determination unit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] This invention relates to a power demand adjustment server and a power demand adjustment system using pumped-storage hydroelectric power. [Background technology]

[0002] Pumped-storage power plants are commonly used as peak-shifting power sources, pumping water during off-peak hours and generating electricity during peak hours.

[0003] Micro-hydropower is defined as a power generation system that utilizes unused energy such as factory wastewater and has a capacity of 100kW or less. Small-scale hydropower is defined as a system that installs a dam-type hydroelectric power plant on a small river and has a capacity of 1MW or less.

[0004] Patent Document 1 describes a technology for controlling pumped-storage power plants connected to a power grid, comprising a plurality of pumped-storage power plants connected to a power grid, and a power command device that transmits active power commands to the plurality of pumped-storage power plants. The power command device determines and transmits active power commands to the plurality of pumped-storage power plants based on the active power of each of the plurality of pumped-storage power plants, the minimum active power of each of the plurality of pumped-storage power plants, a system active power command transmitted from a central control device that manages the supply and demand balance with other systems to specify the system active power required for supply and demand balance, and the rate of change of the system active power required for supply and demand balance, so that an operational pumped-storage power plant among the plurality of pumped-storage power plants can compensate for the minimum active power of one or more pumped-storage power plants that cannot be operated due to a switch in the operating mode.

[0005] Furthermore, Patent Document 2 describes a power supply and demand control device comprising: a power supply procurement risk calculation unit that calculates power supply procurement risk data, which is the probability that a power supply will not be able to output the required power, based on the control achievement probability, which indicates the degree to which control was achieved as commanded in past control operations, and the power output of each power supply; and a power supply and demand control plan modification unit that adds power supplies to the power supply and demand control plan data until the power supply procurement risk data reaches a predetermined standard. It also describes using pumped-storage hydroelectric power as a power supply. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2019-176564 [Patent Document 2] Japanese Patent Publication No. 2019-91106 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] In the Kyushu region, the supply capacity of solar power generation exceeds the demand for electricity, and power generation curtailment orders are issued on a daily basis. From the perspective of solar power generation operators, this makes it difficult to make a profit because they cannot sell electricity, while from the perspective of power transmission grid managers, it is considered an unavoidable decision in order to prioritize the safety of the power grid.

[0008] Not being able to generate electricity during the hours when solar power can be generated represents not only an economic loss but also a missed opportunity to combat global warming. The government is securing subsidies to try to make effective use of solar power generation, and is expanding support for technology development subsidies and subsidies for the installation of expensive storage batteries to realize the early reduction of costs for storage batteries.

[0009] However, the reality is that the high cost of storage batteries is hindering their widespread adoption.

[0010] While Patent Document 2 describes the use of pumped-storage hydroelectric power sources in power supply and demand control, it does not mention a method for determining whether or not to operate the pumped-storage hydroelectric power plant when adjusting to increase power demand.

[0011] The present invention has been made in view of the above circumstances, and aims to provide a power demand adjustment server and power demand adjustment system using pumped-storage hydroelectric power generation that can determine whether or not to operate a pumped-storage hydroelectric power generation device when a request for power demand adjustment is made. [Means for solving the problem]

[0012] To achieve the above objective, the power demand adjustment server according to the first invention is a power demand adjustment server using pumped-storage hydroelectricity for adjusting the power demand of a consumer having a pumped-storage hydroelectric power generation device that generates electricity by pumping water from a lower pond installed at the bottom of a generator motor connected to a water turbine to an upper pond installed at the top, and then flowing the water from the upper pond back to the lower pond. The server is configured to adjust the power demand to increase and includes: an acquisition unit that acquires a per-unit reward corresponding to the adjustment of power demand and the current per-unit electricity rate; a calculation unit that calculates the expected value of pumped-storage hydroelectricity when water is pumped to the upper pond in the power demand adjustment, based on the characteristics of the pumped-storage hydroelectric power generation device and the per-unit electricity rate at the time of power generation; a determination unit that determines whether or not to adjust the power demand to increase based on the per-unit reward corresponding to the adjustment of power demand, the current per-unit electricity rate and the expected value of pumped-storage hydroelectricity; and an output unit that outputs an operation command to the pumped-storage hydroelectric power generation device according to the determination result by the determination unit.

[0013] According to the first invention, when adjusting to increase power demand, an acquisition unit acquires a per-unit reward corresponding to the adjustment of power demand and the current per-unit electricity price. A calculation unit calculates an expected pumped-storage power generation value when water is pumped up to the upper pond in the adjustment of the power demand based on the characteristics of the pumped-storage power generation device and the per-unit electricity price during power generation. Then, a determination unit determines whether to adjust to increase the power demand based on the per-unit reward corresponding to the adjustment of the power demand, the current per-unit electricity price, and the expected pumped-storage power generation value. An output unit outputs an operation command to the pumped-storage power generation device according to the determination result of the determination unit.

[0014] In this way, based on the characteristics of the pumped-storage power generation device and the per-unit electricity price during power generation, an expected pumped-storage power generation value when water is pumped up to the upper pond in the adjustment of the power demand is calculated, and it is determined whether to adjust to increase the power demand based on the per-unit reward corresponding to the adjustment of the power demand, the current per-unit electricity price, and the expected pumped-storage power generation value. Thus, when there is a request for power demand adjustment, it is possible to determine whether to operate the pumped-storage power generation device.

[0015] Also, the power demand adjustment system according to the second invention includes the power demand adjustment server of the above invention and a pumped-storage power generation device.

Advantages of the Invention

[0016] As described above, according to the power demand adjustment server and the power demand adjustment system using pumped-storage power generation of the present invention, an effect that it is possible to determine whether to operate the pumped-storage power generation device when there is a request for power demand adjustment can be obtained.

Brief Description of the Drawings

[0017] [Figure 1] It is a block diagram showing a power demand adjustment system according to an embodiment of the present invention. [Figure 2] It is a schematic diagram showing the configuration of a pumped-storage power generation device according to an embodiment of the present invention. [Figure 3] It is a block diagram showing a server according to an embodiment of the present invention. [Figure 4] It is a flowchart showing the content of a demand adjustment processing routine in a server according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0019] <System Configuration of Power Demand Adjustment System> As shown in FIG. 1, a power demand adjustment system 100 according to an embodiment of the present invention includes a solar power generation device 10, a pumped-storage power generation device 12, and a control device 16 provided for each consumer, and a server 20 provided on the energy center side. The control device 16 and the server 20 for each consumer are interconnected via a network 41 such as the Internet. Note that the server 20 is an example of a power demand adjustment server.

[0020] The pumped-storage power generation device 12 is installed outdoors, for example. As shown in FIG. 2, the pumped-storage power generation device 12 uses a pump 56 to lift water from a lower pond 52 installed below a power generation motor 54 to which a waterwheel (not shown) is connected to an upper pond 50 installed above, and the water flowing from the upper pond 50 to the lower pond 52 rotates the waterwheel to generate power by the power generation motor 54.

[0021] More specifically, when the power demand in the power system to which the pumped-storage power generation device 12 is connected is high or when the electricity charge per unit is high, the waterwheel is rotated by utilizing the height difference and flow rate of the water from the upper pond 50 to the lower pond 52 to perform a power generation operation by the power generation motor 54. On the other hand, when the power demand in the power system to which the pumped-storage power generation device 12 is connected is low, a pumping operation is performed to pump water from the lower pond 52 to the upper pond 50 by operating the pump 56 using the power from the power system.

[0022] The control device 16 controls the operation of the pumped-storage hydroelectric power plant 12 based on the operation command for the pumped-storage hydroelectric power plant 12 at the customer, which is received from the server 20 and determined by the server 20.

[0023] Server 20 adjusts the electricity demand of a group of customers, each consisting of a solar power generation device 10 and a pumped-storage hydroelectric power generation device 12.

[0024] As shown in Figure 3, the server 20 comprises a communication unit 22 and a calculation unit 24. The calculation unit 24 comprises an acquisition unit 30, a calculation unit 32, a determination unit 34, and an output unit 36.

[0025] The communications unit 22 receives requests for power demand adjustment from external sources. The communications unit 22 also receives from external sources the per-unit compensation for power demand adjustment and the current per-unit electricity rate.

[0026] When adjusting to increase electricity demand, the acquisition unit 30 acquires the per-unit reward corresponding to the adjustment of electricity demand, the current per-unit electricity rate, and predetermined characteristics of each customer's pumped-storage power generator 12.

[0027] The calculation unit 32 calculates the expected value of pumped-storage power generation for each customer when water is pumped up to the upper reservoir 50 in order to adjust electricity demand, based on the characteristics of the pumped-storage power generation device 12 and the unit price of electricity generated.

[0028] Specifically, the calculation unit 32 calculates the amount of electricity generated for each customer based on the characteristics of the pumped-storage hydroelectric power generator 12 owned by that customer, assuming that the pumped-storage hydroelectric power generator 12 is operated to pump water from the lower pond 52 to the upper pond 50 for a predetermined time, and then calculates the amount of electricity that can be reduced as an expected value of pumped-storage power generation based on the calculated amount of electricity generated and the unit price of electricity generated.

[0029] More specifically, if a request for electricity demand adjustment is made to increase electricity demand during nighttime hours when the solar power generation device 10 is not generating electricity, the expected value of pumped-storage hydroelectric power generation [yen / kWh] can be calculated as follows.

[0030] Here, for example, the power consumption and generated power of the pumping pump can be obtained by the following equations.

[0031] (Power consumption of pumping pump) = 9.8QH / η P (Generated power) = 9.8QHη G

[0032] Here, as the characteristics of the pumped-storage power generation device 12, the flow rate is Q (m 3 / s), the total head is H (m), the pump efficiency is η P , and the power generation efficiency is η G . Generally, η P , η G is about 0.6.

[0033] For example, when using a pump 56 driven by a motor with a rated output of 100 kW and pumping water for a predetermined time of 3 hours, The theoretical flow rate Q = power consumption × pump efficiency η P / (acceleration due to gravity × total head H) Therefore, if the total head H = 10 m and the pump efficiency η P = 0.6, the theoretical flow rate Q is approximately 36.7 m 3 / min (= 100 (kW) × 0.6 × 10 / (9.8 (m / s 2 )) × 10 (m)), so 6612 m 3 (= 36.7 × 180) of water can be pumped to the upper pond 50 in 3 hours. Generally, the efficiency of an IE3-grade high-efficiency motor with an output of 100 kW is about 96%, but here the motor efficiency is considered 100% for the convenience of calculation.

[0034] Assuming the flow rate during power generation is 36.7 m 3 / min, the total head drop is 10 m, and the power generation efficiency η G = 0.6, then 36 kW (= 9.8 × 0.612 × 10 × 0.6. However, 0.612 (m 3 / s) = 36.7 (m 3It is possible to generate electricity at a rate of 60 kWh per minute for 3 hours, generating a total of 108 kWh. Furthermore, assuming an electricity cost of 30 yen per unit generated, the expected value of pumped-storage hydroelectric power generation is 3240 yen (= 108 x 30), resulting in an electricity cost reduction of 3240 yen.

[0035] The determination unit 34 determines whether or not to adjust the power demand to increase it, based on the per-unit reward corresponding to the adjustment of power demand, the current per-unit electricity rate, and the expected value of pumped-storage hydroelectric power generation.

[0036] Specifically, if pumping water to increase electricity demand during nighttime hours when the solar power generation device 10 is not generating electricity, (Per-unit reward for adjusting electricity demand [yen] + Expected value of pumped-storage hydroelectric power generation [yen]) > Electricity cost for the relevant time period [yen] If this is the case, it is determined that the pump 56 will be used to pump water and adjust the system to increase the power demand.

[0037] For example, when pumping water for 3 hours using a pump 56 with a power consumption of 100 kW, a reward of 20 yen per kWh, corresponding to the adjustment of electricity demand, can be obtained over the course of 3 hours. The power consumption unit for pump 56 is (kW). If the pump is used to pump water for one hour at a power consumption of 100 (kW), the power consumption will be 100 (kW) × 1 (h) = 100 (kWh). If the pump is used to pump water for three hours at a power consumption of 100 (kW), the power consumption will be 100 (kW) × 3 (h) = 300 (kWh). Therefore, the reward will be 6,000 yen (= 300 (kWh) × 20 (yen / kWh)).

[0038] However, for the sake of calculation convenience, we assume that the motor efficiency is 100% and the pump efficiency is 0.6, so the motor input power of 100 kW = the motor rated output of 100 kW, and the pump mechanical output of 60 kW.

[0039] Thus, if pumping water for 3 hours increases electricity demand by 100 kWh, a reward of 6,000 yen can be obtained. Furthermore, let's assume that the time period during which the pumped-storage power generator 12 discharges water for power generation is a time period when electricity rates are high under the dynamic pricing system, and that the electricity rate is selected to be 30 yen / kWh. The reward [yen] + expected value of pumped-storage power generation [yen] is 9,240 yen. On the other hand, the electricity cost during that time period is 9,000 yen (= 3 × 100 × 30).

[0040] Therefore, since 9240 yen > 9000 yen, it is determined that the electricity demand should be adjusted to increase.

[0041] As described above, the amount of electricity generated by pumped-storage hydropower and the amount of electricity consumed by the pumped-storage hydropower remain constant, but the amount of compensation and the electricity price per unit for that time period fluctuate depending on the market. Therefore, it may be possible to use a learning model to determine when to release water for power generation, based on real-time electricity market prices and past electricity price trends, in order to obtain the maximum profit.

[0042] The output unit 36 ​​outputs an operation command to the pumped-storage hydroelectric power plant 12 to each customer according to the determination result.

[0043] <Operation of the power demand adjustment system 100> Next, the operation of the power demand adjustment system 100 according to this embodiment will be described.

[0044] When a request for power demand adjustment is received, the server 20 executes the demand adjustment processing routine shown in Figure 4.

[0045] First, in step S100, when adjusting to increase electricity demand, the acquisition unit 30 acquires the per-unit reward corresponding to the adjustment of electricity demand, the current per-unit electricity rate, and the characteristics of the pumped-storage power generators 12 of each customer having a pumped-storage power generator 12.

[0046] In step S102, the calculation unit 32 calculates the expected value of pumped-storage power generation for each customer having a pumped-storage power generation device 12, based on the characteristics of the pumped-storage power generation device 12 and the unit price of electricity generated during power generation, when water is pumped up to the upper reservoir 50 in adjusting the power demand.

[0047] In step S104, the determination unit 34 determines whether to adjust the power demand to increase for each customer having a pumped-storage power generator 12, based on the per-unit reward corresponding to the adjustment of power demand, the current per-unit electricity rate, and the expected value of pumped-storage power generation.

[0048] In step S106, the output unit 36 ​​outputs an operation command to each pumped-storage power generator 12 for each customer having a pumped-storage power generator 12, according to the determination result. Then, the demand adjustment processing routine is terminated.

[0049] Then, the control device 16 for each customer controls the operation of the pumped-storage hydroelectric power plant 12 based on the operation command for the pumped-storage hydroelectric power plant 12 received from that customer.

[0050] As described above, according to the power demand adjustment system of the embodiment of the present invention, the expected value of pumped-storage hydroelectric power generation when water is pumped to the upper reservoir is calculated based on the characteristics of the pumped-storage hydroelectric power plant and the unit price of electricity during power generation, and a decision is made whether or not to adjust the power demand to increase based on the unit price of compensation corresponding to the adjustment of power demand, the current unit price of electricity, and the expected value of pumped-storage hydroelectric power generation, thereby making it possible to determine whether or not to operate the pumped-storage hydroelectric power plant when a request for power demand adjustment is made.

[0051] Furthermore, because it can prevent situations where the supply capacity of solar power generation exceeds electricity demand, making it impossible for solar power generation operators to sell electricity, solar power generation operators can increase the utilization rate of their solar power generation facilities and improve the profitability of their power generation business.

[0052] Furthermore, while batteries cannot consume power once fully charged, limiting their effectiveness in adjusting to increase electricity demand, pumped-storage hydroelectric power plants can increase electricity demand indefinitely by allowing natural circulation even when full. Specifically, if instructions requesting electricity demand adjustment to increase demand persist for an extended period and the upper reservoir capacity becomes full, control of pumped-storage hydroelectric power plant operation may be implemented. In this case, pumped-storage operation may be continued if the condition (reward per unit for adjusting electricity demand [yen / kWh]) > (electricity cost for that time period [yen / kWh]) is met. While batteries cannot be used for electricity demand adjustment to increase demand once fully charged, pumped-storage hydroelectric power plants can be used for electricity demand adjustment to increase demand indefinitely.

[0053] Furthermore, pumped-storage hydroelectric power plants utilize natural energy to create an energy storage system by adding an upper reservoir, a lower reservoir (which acts as a water storage tank), and existing backup pumps and generators. This results in less industrial waste compared to battery storage and enables adjustment of electricity demand. The upper reservoir can also be considered an emergency water storage tank.

[0054] Furthermore, by installing pumped-storage hydroelectric power plants at each customer's location, power grid managers can reduce their own investment in pumped-storage power plants and other equipment such as battery storage systems.

[0055] Furthermore, electricity demand can be adjusted by generating electricity through the release of water from the upper reservoir, preventing it from exceeding the electricity demand of consumers.

[0056] It should be noted that the present invention is not limited to the embodiments described above, and various modifications and applications are possible without departing from the spirit of the invention.

[0057] For example, the pumped-storage hydroelectric power plant operation may be controlled even when there is no request for electricity demand adjustment. Even without a request for electricity demand adjustment, if it is profitable to pump water when electricity prices are low and generate electricity during peak hours, the pumped-storage hydroelectric power plant can be automatically operated to increase profitability. For example, if 100 kWh of pumped-storage power is needed, the amount of electricity that can be generated is ηP × ηG = 0.6 × 0.6 = 0.36, so the expected amount of power generated is 36 kWh. However, if water is pumped when electricity prices are 5 yen / kWh and electricity is generated when electricity prices are 20 yen / kWh, the net income will be (generation income) - (pumping expenses) = 20 × 36 (yen) - 100 × 5 (yen) = 220 yen. In this case, there is an economic benefit, so it is decided to operate the pumped-storage hydroelectric power plant. [Explanation of Symbols]

[0058] 10. Solar power generation equipment 12 Pumped-storage hydroelectric power plants 16 Control device 20 servers 22 Communications Department 24 Arithmetic section 30 Acquisition Department 32 Calculation Section 34 Judgment section 36 Output section 50 Upper Pond 52 Lower Pond 54 Generator and Motor 56 pumps 100 Power Demand Adjustment System

Claims

1. A power demand adjustment server using pumped-storage hydroelectric power generation for adjusting the power demand of a consumer having a pumped-storage hydroelectric power generation system that generates electricity by pumping water from a lower reservoir located below a generator motor connected to a water turbine to an upper reservoir located above, and then flowing the water from the upper reservoir back to the lower reservoir, When adjusting to increase electricity demand, the acquisition unit acquires a per-unit reward corresponding to the adjustment of electricity demand and the current per-unit electricity rate. A calculation unit that calculates the expected value of pumped-storage hydroelectric power generation when water is pumped to the upper reservoir in adjusting the electricity demand, based on the characteristics of the pumped-storage hydroelectric power generation device and the unit price of electricity generated. A determination unit that determines whether or not to adjust to increase electricity demand based on the per-unit reward corresponding to the adjustment of electricity demand, the current per-unit electricity rate, and the expected value of the pumped-storage hydroelectric power generation, An output unit that outputs an operation command to the pumped-storage power plant according to the determination result by the determination unit, A power demand adjustment server, including one.

2. The calculation unit calculates the amount of power generated according to the amount of water pumped when the pumped-storage power generation device is operated to pump water from the lower pond to the upper pond for a predetermined time based on the characteristics of the pumped-storage power generation device, and calculates the amount of electricity that can be reduced as the expected value of pumped-storage power generation based on the calculated amount of power generated and the unit price of electricity generated.

3. The aforementioned consumer is the power demand adjustment server according to claim 1, further comprising a solar power generation device.

4. A power demand adjustment server according to any one of claims 1 to 3, Pumped-storage hydroelectric power plant, A power demand adjustment system that includes this.

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