WO2012046832A1

WO2012046832A1 - Power supply system

Info

Publication number: WO2012046832A1
Application number: PCT/JP2011/073181
Authority: WO
Inventors: 敦史須山
Original assignee: 三洋電機株式会社
Priority date: 2010-10-08
Filing date: 2011-10-07
Publication date: 2012-04-12
Also published as: JP2014003726A

Abstract

[Objective] To provide a power supply system, wherein charging/discharging of a power storage unit is controlled according to the price per unit power-amount of commercial power, which may fluctuate. [Solution] The power supply system (1) is provided with: a power storage unit (10) that consumes commercial power to conduct charging thereof and discharges the charged power to supply power; a price information acquisition unit (11) that acquires price information indicating the price per unit power-amount of commercial power; and a power-storage-unit control unit (12) that controls charging and/or discharging of the power storage unit (10). The power-storage-unit control unit (12) controls charging and/or discharging of the power storage unit (10), by obtaining the price per unit power-amount of the power charged in the power storage unit (10) on the basis of the price information acquired by the price information acquisition unit, and the price per unit power-amount of commercial power.

Description

Power supply system

The present invention relates to a power supply system that uses power supplied by discharging a storage battery.

Due to the liberalization of electricity, the entities that supply electricity to consumers (for example, homes, stores, buildings, etc.) are diversifying. For example, not only an electric power company that supplies electric power generated by itself, but also an electric power company that supplies electric power by selling electric power purchased from others can be the main entity that supplies electric power.

The above-mentioned electric power company sets a price (hereinafter referred to as a unit price) per unit power amount (for example, 1 kWh) of power (hereinafter referred to as commercial power) supplied to the consumer. For example, electric power companies that have large-scale power generation facilities and supply power to all consumers in a given area are cheaper at night when the demand for commercial power is high and the demand for commercial power is low. The fixed unit price is often set in a contract with a consumer.

Further, consumers are increasingly using a power supply system that can supply not only commercial power but also power supplied by discharging a storage battery. The storage battery can be discharged at an arbitrary timing and supplied with power by consuming commercial power and charging in advance. That is, a consumer who uses such a power supply system can change the timing of consuming commercial power by controlling the timing of charging and discharging the storage battery. For example, in Patent Document 1, the storage battery is charged at a specific time (22:00 to 8:00) where the unit price of commercial power is low, and the storage battery is discharged at a specific time (from 8:00 to 22:00) where the unit price of commercial power is high. By controlling in this way, a power supply system has been proposed that reduces the price of commercial power.

JP 2004-249481 A

By the way, in the buying and selling of commercial power between power companies, variable unit prices are often set. Similarly, the unit price of variability may be set in the buying and selling of commercial power between the power company and the consumer. In this case, the time when the unit price of commercial power is high or the time when the unit price is low may vary. Therefore, for example, in the power supply system proposed in Patent Document 1, it is impossible to grasp the time when the unit price of commercial power is high or the time when the unit price is low, and it becomes impossible to reduce the price of commercial power.

In addition, electric power companies often set the unit price higher when the demand for commercial power is large, and set the unit price cheaper when the demand for commercial power is small. This is because the unit price is the same regardless of whether the unit price is fixed or variable, and the unit price is determined by the relationship between supply and demand. Furthermore, power companies that can generate power often respond by increasing the power generated by thermal power generation with high responsiveness when the demand for commercial power increases. Therefore, it is preferable to reduce the amount of commercial power consumed during a time when the unit price is high, from the viewpoint of reducing the amount of carbon dioxide emissions associated with thermal power generation as well as reducing the price of commercial power.

Therefore, an object of the present invention is to provide a power supply system that controls charging and discharging of a power storage unit according to a price per unit power amount of commercial power that may fluctuate.

In order to achieve the above object, the power supply system according to the present invention includes a power storage unit that consumes and charges commercial power, supplies the charged power by discharging, and information indicating a price per unit power amount of the commercial power. A price information acquisition unit that acquires certain price information, a price per unit power amount of power charged in the power storage unit, and a unit power amount of commercial power based on the price information acquired by the price information acquisition unit A power storage unit control unit that controls at least one of charging and discharging of the power storage unit by obtaining and comparing the winning price.

Further, in the power supply system configured as described above, when the power storage unit control unit has a price per unit power amount of power charged in the power storage unit higher than a price per unit power amount of commercial power, Control that allows charging of the power storage unit, and discharge of the power storage unit when the price per unit power amount of commercial power is higher than the price per unit power amount of power charged in the power storage unit. It is also possible to perform at least one of the allowable control.

With this configuration, it is possible to preferentially consume power with a low price per unit power. Therefore, it becomes possible to reduce the power charge of commercial power.

Further, in the power supply system having the above configuration, the power storage unit control unit is configured such that a price per unit power amount of power charged in the power storage unit is per unit power amount when commercial power is charged in the power storage unit. The price per unit electric energy when the electric power charged in the electric storage unit is discharged when the electric power charged in the electric storage unit is discharged. If it is higher than that, at least one of the control to permit discharge of the power storage unit may be performed.

With this configuration, it is possible to accurately determine power with a low price per unit power amount in consideration of a decrease in power amount due to charging or discharging, and to consume the power with priority. For this reason, it is possible to effectively reduce the commercial electricity charge.

Further, in the power supply system having the above configuration, the power storage unit control unit determines that the price per unit power amount of power charged in the power storage unit is a reciprocal of charging efficiency to the price per unit power amount of commercial power. When the price is higher than the price obtained by multiplying, the control for allowing charging of the power storage unit and the price per unit power amount of commercial power are the same as the price per unit power amount of power charged in the power storage unit. When the price is higher than the price obtained by multiplying the reciprocal of the discharge efficiency, at least one of the control to permit the discharge of the power storage unit may be performed.

With this configuration, the price per unit power amount when commercial power is charged to the power storage unit and the price per unit power amount when power stored in the power storage unit is discharged are calculated easily and accurately. It becomes possible to do.

Further, in the power supply system configured as described above, when the power storage unit control unit controls the power storage unit to charge, the power amount charged in the power storage unit before the charging is changed to the power amount before the charging. Obtained by multiplying the value obtained by multiplying the price per unit amount of power charged in the power storage unit and the amount of commercial power consumed by the charge by the price per unit amount of commercial power The value obtained by dividing the sum of the value and the amount of power charged in the power storage unit after the charging may be used as the price per unit power of the power charged in the power storage unit after the charging. I do not care.

With this configuration, the amount of power that is charged in the power storage unit before charging, the price per unit power amount of power that is charged in the power storage unit before charging, and the amount of commercial power that is consumed during charging Therefore, it is possible to easily obtain the price per unit power amount of the electric power charged in the power storage unit after charging only by grasping the price (price information) per unit power amount of the commercial power. For example, without knowing (recording) the amount of commercial power consumed when charging all the power storage units in the past and the price per unit power of commercial power at that time, The price per unit electric energy can be obtained.

Further, in the power supply system configured as described above, the power storage unit control unit obtains a value obtained by multiplying the difference between the remaining capacities of the power storage unit before and after charging by the reciprocal of charging efficiency, and the commercial power consumed by the charging. It does not matter as the amount of power.

With this configuration, the power storage unit control unit can easily and accurately obtain the amount of commercial power consumed by charging simply by checking the remaining capacity of the power storage unit before and after charging.

Further, in the power supply system configured as described above, the charging efficiency is a value obtained by dividing the amount of commercial power consumed to charge the power storage unit and the amount of power stored in the power storage unit by the charging. The discharge efficiency may be a value obtained by dividing the amount of power lost by the power storage unit by discharging the power storage unit and dividing the amount of power supplied by the power storage unit by the discharge. .

In the power supply system having the above configuration, the price per unit time of commercial power can fluctuate per unit time, and the price per unit power amount increases as the unit time increases. It does not matter.

In this case, it is possible to reduce the price of commercial power and reduce the carbon dioxide emissions of the power company.

With the configuration of the present invention, even if the price per unit power amount of commercial power fluctuates and the price per unit power amount of power charged in the power storage unit fluctuates accordingly, It becomes possible to control charging and discharging of the part.

The significance or effect of the present invention will be further clarified by the following description of embodiments. However, the following embodiment is merely one of the embodiments of the present invention, and the meaning of the terminology of the present invention or each constituent element is limited to those described in the following embodiments. is not.

These are block diagrams explaining an example of the electric power supply method by an electric power provider. These are graphs which show an example of the fluctuation | variation of the unit price of commercial power. These are block diagrams which show the structural example of the electric power supply system which is one Embodiment of this invention. FIG. 4 is a flowchart illustrating an example of a control operation of a power storage unit by a power storage unit control unit of the power supply system of FIG. 3.

A power supply system according to an embodiment of the present invention will be described below with reference to the drawings. First, an example of a method in which an electric power company supplies electric power to a consumer having an electric power supply system will be described.
<Power supply method by electric power companies>
FIG. 1 is a block diagram illustrating an example of a method of supplying power by an electric power company. The solid arrows connecting the blocks in FIG. 1 indicate the exchange of power, and the broken arrows indicate the exchange of information. In addition, the example shown in FIG. 1 illustrates the case where power is supplied to consumers C1 to C3 via wholesale power supplier S1 and power supply manager S2. Note that both the wholesale power supplier S1 and the power supply manager S2 can be interpreted as one form of the power company.

As shown in FIG. 1, the wholesale power supplier S1 acquires commercial power by generating power by itself or purchasing it from another power company at the wholesale power exchange M. The power supply manager S2 purchases commercial power from the wholesale power supplier S1. The power supply manager S2 may purchase commercial power from another power company at the wholesale power exchange M without going through the wholesale power supplier. In addition, in the buying and selling of commercial power at the wholesale power exchange M and the buying and selling of commercial power at the wholesale power supplier S1 and the power supply manager S2, the commercial power may be traded at a variable unit price. Commercial power may be traded at a unit price.

The power supply manager S2 sells and supplies commercial power to, for example, consumers C1 to C3 in the apartment house. In addition, the power supply manager S2 sells commercial power at a variable unit price and notifies the consumers C1 to C3 of price information indicating the unit price of commercial power. For example, the unit price of the commercial power may vary every unit time (for example, 1 hour or 30 minutes).

The fluctuation of the unit price of commercial power will be described with reference to FIG. FIG. 2 is a graph showing an example of fluctuations in the unit price of commercial power. In the graph shown in FIG. 2, the unit time is 1 hour, and the unit price of commercial power in each unit time is indicated by the height of the bar. As shown in FIG. 2, the power supply manager S2 can set a unit price of commercial power that varies from moment to moment.

For example, the price information may indicate the unit price of commercial power in one unit time at the present time (or the latest), or may indicate the unit price of commercial power in a plurality of unit times in the future. . In the following, for concrete explanation, the price information indicates the unit price of commercial power in one unit time (or the most recent), and the power supply manager S2 makes a unit time (for example, each The case where price information is notified to consumers C1 to C3 at the start of unit time) will be exemplified.
<Power supply system>
Next, the power supply system possessed by the consumers C1 to C3 in FIG. 1 (consumer C in FIG. 3) will be described with reference to the drawings. FIG. 3 is a block diagram illustrating a configuration example of the power supply system according to the embodiment of the present invention. As in FIG. 1, in FIG. 3, the power exchange of each block is indicated by a solid arrow, and the information exchange is indicated by a broken arrow.

As shown in FIG. 3, the power supply system 1 of the consumer C includes a power storage unit 10 that consumes and charges commercial power and supplies the charged power by discharging, and a price information acquisition unit 11 that acquires price information. And at least one of a power storage unit control unit 12 that controls charging and discharging of the power storage unit 10 based on price information acquired by the price information acquisition unit 11, and commercial power and power supplied by discharging of the power storage unit 11. A load unit 13 for consumption.

The power storage unit 10 is composed of, for example, a large-capacity storage battery, is charged by appropriately converting supplied commercial power (for example, converting AC power to DC power), and appropriately converting the charged power (for example, The DC power is converted into AC power and supplied to the load unit 13. In addition, the power storage unit 10 estimates the amount of charged electric power (hereinafter referred to as remaining capacity) and notifies the power storage unit control unit 12 of the estimated amount. For example, the power storage unit 10 measures the amount of electric power or current to be charged and discharged, or includes a table indicating the relationship between the voltage value of the power storage unit 10 and the remaining capacity, and measures the voltage value of the power storage unit 10 and the table. The remaining capacity is estimated by referring to.

The price information acquisition unit 11 includes, for example, a smart meter that can communicate with the power supply manager S2, and acquires price information notified from the power supply manager S2. The price information acquisition unit 11 recognizes the unit price of commercial power by acquiring the price information, and the unit price is given to the consumer C by light (for example, image display, lamp lighting, etc.) or sound. You may notify.

The power storage unit control unit 12 performs at least one of charging and discharging of the power storage unit 10 based on the remaining capacity acquired from the power storage unit 10 and the price information acquired by the price information acquisition unit 11. In the following, for the sake of concrete explanation, a case where the power storage unit control unit 12 can control charging and discharging of the power storage unit 10 is illustrated.

The load unit 13 includes various loads that operate by consuming the supplied power (for example, various devices such as lighting, air conditioners, and refrigerators provided in homes and stores). Further, a part or all of the load of the load unit 13 can consume not only commercial power but also power supplied by discharging the power storage unit 10.

An example of charging and discharging control operations of the power storage unit 10 by the power storage unit control unit 12 will be described with reference to the drawings. FIG. 4 is a flowchart illustrating an example of the control operation of the power storage unit by the power storage unit control unit of the power supply system of FIG. 3.

As shown in FIG. 4, when the power storage unit control unit 12 starts operating, each value is initialized first. Specifically, the variable t is set to 1, and Cost_ave (1), which is a price (ie, unit price) per unit power amount (for example, 1 kWh) of the electric power charged in the power storage unit 10, is set ( STEP 1). As Cost_ave (1), for example, Cost_ave (t) obtained at the end of the previous operation may be applied, or a value based on the remaining capacity of the power storage unit 10 may be used. Also, a predetermined value such as 0 may be used.

Next, the power storage unit control unit 12 confirms whether or not price information has been acquired via the price information acquisition unit 11 (STEP 2). The power storage unit control unit 12 stands by unless price information is acquired (STEP 2, NO).

When confirming that the price information has been acquired (STEP 2, YES), the power storage unit control unit 12 confirms whether or not the remaining capacity SOC (t) of the power storage unit 10 is substantially 0 (STEP 3). When the remaining capacity SOC (t) of the power storage unit 10 is not substantially 0 (greater than 0) (STEP 3, NO), it is determined whether or not the power storage unit 10 is allowed to discharge (STEP 4). Specifically, it is determined whether or not discharge of the power storage unit 10 is allowed by checking whether or not the following formula (1) is satisfied. In the following formula (1), Cost_now (t) is the current unit price of commercial power that the power storage unit control unit 12 grasps from the price information. Β is the reciprocal of discharge efficiency (the amount of power lost by the power storage unit 10 by discharging the power storage unit 10 and obtained by dividing the amount of power supplied by the power storage unit 10 by the discharge).

When satisfy | filling said Formula (1) (STEP4, YES), the electrical storage part control part 12 accept | permits discharge of the electrical storage part 10 (STEP5). Thereby, the load part 13 can consume the electric power supplied by discharge of the electrical storage part 10. FIG. When this control is completed (for example, when the end time of the unit time is reached), the power storage unit control unit 12 increases the variable t by 1 for the control of the power storage unit 10 in the next unit time (STEP 6). Further, the unit price Cost_ave (t−1) of the power charged in the power storage unit 10 in the current unit time is set as the unit price Cost_ave (t) of the power charged in the power storage unit 10 in the next unit time ( (Step 7).

And the electrical storage part control part 12 confirms whether control of the electrical storage part 10 is complete | finished (STEP8). When it is confirmed that the control of the power storage unit 10 is not terminated (STEP 8, NO), the process returns to STEP 2 to confirm acquisition of price information. On the other hand, when it is confirmed that the control of the power storage unit 10 is to be ended (STEP 8, YES), the control of the power storage unit 10 is ended.

On the other hand, when the above formula (1) is not satisfied (STEP 4, NO), it is determined whether or not charging of the power storage unit 10 is permitted (STEP 9). Specifically, it is determined whether or not charging of the power storage unit 10 is permitted by checking whether or not the following formula (2) is satisfied. In the following formula (2), α is the charging efficiency (the amount of commercial power consumed to charge the power storage unit 10 and obtained by dividing the amount of power stored in the power storage unit 10 by the charging). Is the reciprocal of

When the above equation (2) is satisfied (STEP9, YES) and the remaining capacity SOC (t) is not substantially equal to the maximum value MAX (smaller than the maximum value MAX) (STEP10, NO), the power storage unit control unit 12 Charging the power storage unit 10 is allowed (STEP 11). Thereby, while the electrical storage part 10 can consume and charge commercial power, the load part 13 can consume commercial power. When this control ends (for example, when the end time of the unit time is reached), the power storage unit control unit 12 increases the variable t by 1 for the control of the power storage unit 10 in the next unit time (STEP 12). Further, the unit price Cost_ave (t) of the power charged in the power storage unit 10 in the next unit time is calculated as in the following formula (3) (STEP 13). However, in the following formula (3), t is an integer of 2 or more.

When the power storage unit control unit 12 calculates the unit price Cost_ave (t) of the power charged in the power storage unit 10 in the next unit time as in the above equation (3), the control of the power storage unit 10 is performed as described above. It is confirmed whether or not to end (STEP 8).

On the other hand, when the above equation (2) is not satisfied (STEP 9, NO), or when the remaining capacity SOC (t) is substantially equal to the maximum value MAX (STEP 10, YES), the power storage unit control unit 12 Do not allow charging and discharging. Thereby, the load part 13 can consume commercial power. When this control is completed (for example, when the end time of the unit time is reached), the power storage unit control unit 12 increases the variable t by 1 as described above (STEP 6), and the power storage unit 10 in the next unit time is changed. The unit price Cost_ave (t) of the charged electric power is set (STEP 7), and it is confirmed whether or not the control of the power storage unit 10 is finished (STEP 8).

By the way, when the remaining capacity SOC (t) of the power storage unit 10 is substantially 0 (STEP 3, YES), the power storage unit control unit 12 allows the power storage unit 10 to be charged (STEP 11). Then, as described above, the power storage unit control unit 12 increases the variable t by 1 (STEP 12), and calculates the unit price Cost_ave (t) of the power charged in the power storage unit 10 in the next unit time (STEP 13). ), Whether to end the control of the power storage unit 10 is confirmed (STEP 8).

If comprised as mentioned above, even if the unit price of commercial power changes and the unit price of the electric power charged in the power storage unit 10 fluctuates accordingly, charging and discharging of the power storage unit 10 are controlled so as to be suitable for it. It becomes possible. In addition, this makes it possible to reduce the price of commercial power and reduce the amount of carbon dioxide emitted by the power company.

Further, the case where the above expression (1) is satisfied in STEP 4 is a case where the unit price Cost_now (t) of the commercial power is higher than the unit price Cost_ave (t) of the power charged in the power storage unit 10. Therefore, by allowing discharge of power storage unit 10 in this case, it is possible to preferentially consume power with low unit price (power charged in power storage unit 10). Therefore, it becomes possible to reduce the power charge of commercial power.

Further, when the above formula (1) is satisfied in STEP 4, the unit cost Cost_now (t) of the commercial power is more than the unit cost Cost_ave (t) × β when the power charged in the power storage unit 10 is discharged. This is when it becomes higher. Therefore, in this case, by allowing the power storage unit 10 to discharge, considering the reduction of the amount of power accompanying the discharge of the power storage unit 10, the power with low unit price (power charged in the power storage unit 10) can be accurately obtained. This makes it possible to preferentially consume the power. Therefore, it is possible to effectively reduce the commercial electricity charge.

Similarly, the case where the expression (2) is satisfied in STEP 9 is a case where the unit price Cost_ave (t) of the power charged in the power storage unit 10 is higher than the unit price Cost_now (t) of the commercial power. . Therefore, by allowing charging of the power storage unit 10 in this case, it is possible to preferentially consume power (commercial power) with a low unit price. Therefore, it becomes possible to reduce the power charge of commercial power.

Further, when the above formula (2) is satisfied in STEP 9, the unit price Cost_ave (t) of the power charged in the power storage unit 10 is the unit price Cost_now (t) when the commercial power is charged in the power storage unit 10 It is a case where it becomes higher than xα. Therefore, in this case, by allowing charging of the power storage unit 10, power (commercial power) with a low unit price is accurately determined in consideration of a decrease in the amount of power accompanying charging of the power storage unit 10, and the power is given priority. Consumption. Therefore, it is possible to effectively reduce the commercial electricity charge.

Moreover, when the reciprocal α of charging efficiency and the reciprocal β of discharging efficiency are used as in the above formula (1) and the above formula (2), the unit cost Cost_now (t) × α when the power storage unit 10 is charged with commercial power. In addition, the unit price Cost_ave (t) × β when the power charged in the power storage unit 10 is discharged can be easily and accurately calculated.

Moreover, when the unit price Cost_ave (t) of the power charged in the power storage unit 10 in the next unit time is calculated as in the above equation (3), the amount of power SOC ( t-1), unit price Cost_ave (t-1) of power charged in the power storage unit 10 before charging, and amount of commercial power consumed at the time of charging {SOC (t) -SOC (t-1)} It is possible to easily calculate × α only by grasping the unit price (price information) Cost_now (t−1) of the commercial power. For example, the unit price of power charged in the power storage unit 10 is obtained without grasping (recording) the amount of commercial power consumed when charging all the power storage units 10 in the past and the unit price of commercial power at that time. It becomes possible.

Furthermore, the power storage unit control unit 12 can easily and accurately determine the amount of commercial power consumed by charging simply by checking the remaining capacities SOC (t) and SOC (t−1) of the power storage unit 10 before and after charging. It is possible to ask.

In addition, when the price information notified to the consumers C1 to C3, C by the power supply manager S2 indicates the unit price of a plurality of unit times (the unit price of commercial power in each future unit time is notified in advance) In step 2 of FIG. 4, it may be confirmed whether or not the unit time has started. In this case, the power storage unit control unit 12 waits unless confirming the start of the unit time (corresponding to NO in STEP 2), and performs STEP 3 by confirming the start of the unit time (corresponding to YES in STEP 2).

In STEP 3 of FIG. 4, the power storage unit control unit 12 may confirm whether or not the remaining capacity SOC (t) of the power storage unit 10 is smaller than a predetermined value. The predetermined value is set to a value small enough to determine that the power storage unit 10 needs to be charged. In this case, the power storage unit control unit 12 performs STEP 11 if the remaining capacity SOC (t) of the power storage unit 10 is smaller than the predetermined value (corresponding to YES in STEP 3), and if it is equal to or greater than the predetermined value (NO in STEP 3) Step 4 is performed.

Moreover, in STEP10 of FIG. 4, the electrical storage part control part 12 may confirm whether the remaining capacity SOC (t) of the electrical storage part 10 is larger than a predetermined value. The predetermined value is set to a value large enough to determine that charging of the power storage unit 10 is unnecessary. In this case, the power storage unit control unit 12 performs STEP 6 if the remaining capacity SOC (t) of the power storage unit 10 is larger than the predetermined value (corresponding to YES in STEP 10), and if it is less than the predetermined value (NO in STEP 10). Step 11 is performed.
<Modification>
Regarding the power supply system 1 which is an embodiment of the present invention, a part or all of the operations of the price information acquisition unit 11, the power storage unit control unit 12, the power storage unit 10 and the like may be performed by a control device such as a microcomputer. I do not care. Further, all or part of the functions realized by such a control device is described as a program, and the program is executed on a program execution device (for example, a computer) to realize all or part of the functions. It doesn't matter if you do.

Further, the power supply system 1 shown in FIG. 3 is not limited to the above-described case, and can be realized by hardware or a combination of hardware and software. Further, when realizing a part of the power supply system 1 using software, a block for a part realized by the software represents a functional block of the part.

The embodiment of the present invention has been described above, but the scope of the present invention is not limited to this, and various modifications can be made without departing from the spirit of the invention.

The present invention can be used for a power supply system that uses power supplied by discharging a power storage unit.

DESCRIPTION OF SYMBOLS 1 Power supply system 10 Power storage part 11 Price information acquisition part 12 Power storage part control part 13 Load part

Claims

A power storage unit that consumes and charges commercial power and supplies the charged power by discharging;
A price information acquisition unit that acquires price information that is information indicating a price per unit amount of commercial power;
Based on the price information acquired by the price information acquisition unit, a price per unit power amount of power charged in the power storage unit and a price per unit power amount of commercial power are respectively obtained and compared. And a power storage unit control unit for controlling at least one of charging and discharging of the power storage unit,
A power supply system comprising:
The power storage unit controller
Control for allowing charging of the power storage unit when the price per unit power amount of power charged in the power storage unit is higher than the price per unit power amount of commercial power;
Control for allowing discharge of the power storage unit when the price per unit power amount of commercial power is higher than the price per unit power amount of power charged in the power storage unit;
The power supply system according to claim 1, wherein at least one of the following is performed.
The power storage unit controller
Control that allows charging of the power storage unit when the price per unit power amount of power charged in the power storage unit is higher than the price per unit power amount when commercial power is charged in the power storage unit When,
Control for allowing discharge of the power storage unit when the price per unit power amount of commercial power is higher than the price per unit power amount when the power charged in the power storage unit is discharged;
The power supply system according to claim 1 or 2, wherein at least one of the following is performed.
The power storage unit controller
Control that allows charging of the power storage unit when the price per unit power amount of power charged in the power storage unit is higher than the price per unit power amount of commercial power considering charging efficiency;
When the price per unit power amount of commercial power is higher than the price per unit power amount of power charged in the power storage unit taking into account the discharge efficiency, control that allows discharge of the power storage unit,
The power supply system according to claim 3, wherein at least one of the following is performed.
The price per unit amount of commercial power considering the charging efficiency is
This is the price obtained by multiplying the price per unit of commercial power by the reciprocal of charging efficiency,
The price per unit amount of power charged in the power storage unit taking into account the discharge efficiency is obtained by multiplying the price per unit power amount of power charged in the power storage unit by the reciprocal of the discharge efficiency. The power supply system according to claim 4, which is a price.
When the power storage unit control unit controls the power storage unit to charge,
A value obtained by multiplying the amount of power charged in the power storage unit before the charging by the price per unit power amount of power charged in the power storage unit before the charging;
Sum of the value obtained by multiplying the amount of commercial power consumed by the charging by the price per unit amount of commercial power,
A value obtained by dividing by the amount of power charged in the power storage unit after the charging,
The power supply system according to any one of claims 1 to 5, wherein a price per unit amount of electric power charged in the power storage unit after the charging is used.
For commercial power, the price per unit power amount can fluctuate per unit time.
The power supply system according to any one of claims 1 to 6, wherein the price per unit power amount increases as the demand increases.