POWER INFORMATION MANAGEMENT DEVICE, POWER INFORMATION MANAGEMENT SYSTEM, AND POWER INFORMATION MANAGEMENT METHOD

A household electric appliance is operated with alternating current power. The household electric appliance is operated also with direct current power. A communication terminal displays a screen by execution of a power management application of a power management system including the household electric appliance. A graph of the screen indicates power consumption of each day for one month, more specifically, indicates consumption of direct current power supplied from a direct current power source to the household electric appliance together with consumption of alternating current power supplied from an alternating current power source thereto.

TECHNICAL FIELD

This application claims the priority benefit of Japanese Patent Application No. 2015-170660 filed in Japan on Aug. 31, 2015, the contents of which is incorporated by reference herein in its entirety.

The present disclosure relates to provision of power information, and particularly relates to provision of information about power consumed by a load device that is operated with either alternating current power or direct current power.

BACKGROUND ART

Conventionally, various HEMSs (Home Energy Management Systems), in which the amount of energy usage such as electricity or gas in a household electric appliance or an electric facility is displayed, have been proposed as energy saving measures. For example, Japanese Unexamined Patent Application Publication No. 11-248752 (PTL 1) proposes a device that displays, for a consumer, his or her daily power consumption and a current state of the power consumption with respect to a power-saving target value in real time in order to reduce power consumption.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In conventional techniques, it is only assumed that energy saving is achieved by suppressing power consumption.

On the other hand, a technique in which energy saving is achieved by operating an appliance with direct current power has been recently proposed (refer to PTL 2). In a case where power is supplied with alternating current power to an appliance that is operated with direct current power, AC-DC conversion is performed, so that a power loss is caused by the conversion. Thus, operating the appliance with the direct current power without performing the AC-DC conversion is considered to exert an effect of reducing power consumption. In the conventional technique, however, there is no means to inform an effect of reduction in power consumption by operating an appliance with direct current power.

The disclosure was made in view of such circumstances and an object thereof is to provide a power information management device, a power information management system, and a power information management method that are able to inform an effect of reduction in power consumption by operating an appliance with direct current power.

Solution to Problem

According to a certain aspect of the disclosure, provided is a power information management device that acquires information about power consumption of a load device that is operated by using alternating current power and direct current power as power, and generates display information about power consumption of the direct current power of the load device.

It is preferable that the display information includes display information about the power consumption of the direct current power of the load device, and includes information for displaying information about consumption of the alternating current power of the load device and the information about the consumption of the direct current power of the load device in different forms.

It is preferable that the display information includes first display information about the power consumption of the direct current power of the load device in a first period, and, second display information about the power consumption of the direct current power of the load device in each of second periods when the first period is divided into each of the second periods. The first display information is display information in which power consumption per first period is displayed distinctively in accordance with a proportions of the consumption of the direct current power and the consumption of the alternating current power. The second display information is display information in which, in each of the second periods, when the consumption of the direct current power occupies a certain proportion or more with respect to the power consumption of the second period, the power consumption of the second period is all regarded as the consumption of the direct current power.

It is preferable that the power information management device acquires operation time information indicating a time during which the load device is operated and switching information indicating, together with the time, with which of the alternating current power or the direct current power the load device is operated. In the operation time information, the power information management device specifies, as the consumption of the direct current power of the load device, consumption of power for a time during which the load device is operated with the direct current power in the switching information.

According to another aspect of the disclosure, provided is a power information management system, including: a direct current power source; a load device that is operated by using alternating current power and direct current power as power; and a power information management device that acquires information about power consumption of the load device, and generates display information about power consumption of the direct current power of the load device.

According to still another aspect of the disclosure, provided is a power information management method, including the steps of: acquiring information about power consumption of a load device that is operated by using alternating current power and direct current power as power and generating display information about power consumption of the direct current power of the load device.

According to still another aspect of the disclosure, provided is a power information management device. The power information management device acquires information about power consumption of a plurality of load devices including a load device that is operated with alternating current power and a load device that is operated with direct current power. The power information management device generates display information for displaying information about consumption of the alternating current power of the plurality of load devices and information about consumption of the direct current power of the plurality of load devices in different forms.

Advantageous Effects of Invention

According to the disclosure, information about consumption of direct current power by operating an appliance with direct current power is displayed. This makes it possible for a user to easily recognize an effect of reduction in power consumption.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the disclosure will be described with reference to drawings. In the following description, the same elements have the same reference signs allotted. Their designation and function are also identical. Therefore, detailed description thereof will not be repeated.

First Embodiment

1. Overview of Embodiment

FIG. 1illustrates a power management system1according to a first embodiment. The power management system1ofFIG. 1includes a HEMS (home energy management system) controller10. The power management system1also includes a communication terminal100as an example of a power information management device. InFIG. 1, household electric appliances14to17are operated both with alternating current power from an alternating current power source11and with direct current power from a direct current power source12or13. The household electric appliances14to17are controlled, for example by the HEMS controller10, to use power from which power source to operate depending on a situation.

The communication terminal100has a touch panel141and a display142provided on a front side thereof. The communication terminal100displays, on the display142, information about power consumption of the household electric appliances14to17.FIG. 2illustrates an example of display of power consumption of the household electric appliances14to17in the communication terminal100.

As illustrated inFIG. 2, a screen510displayed in the communication terminal100includes a graph511. The graph511indicates the power consumption of an appliance among the household electric appliances14to17during a certain month (1st to 30th of a certain month). A vertical axis of the graph511indicates consumption (kWh). The graph511is a bar graph including a plurality of bars and each of the bars indicates the power consumption of each day.

The graph511indicates the consumption of the alternating current power and the consumption of the direct current power in different forms. More specifically, five bars from a left end that indicate the consumption from the first day to the fifth day indicate the consumption of the alternating current power in lower parts thereof and indicate the consumption of the direct current power in upper parts thereof. Bars (the sixth bar from the left and bars positioned on the right side therefrom) corresponding to days subsequent to the sixth day do not include the consumption of the direct current power.

That is, the graph511indicates the consumption of the direct current power and the consumption of the alternating current power of each day in different forms.

Note that, a display target period as illustrated inFIG. 2is able to be changed. The screen510includes an input unit512that is used to change a length of the display target period and an input unit513that is used to change the display target period.

The screen510also includes, as a “total usage”, a result (0.3 kWh) of the power consumption (direct current power and alternating current power) of a household electric appliance as a display target in the display target period. Further, the screen510includes, as a “reference cost”, when the consumption of the direct current power is exchanged with the consumption of the alternating current power, an estimated amount (2835 yen) for the resultant consumption of the household electric appliance of the display target, which is to be paid to a supply source (power company) of the alternating current power source11.

2. Configuration of Power Management System

A configuration of the power management system1ofFIG. 1will be described.

As illustrated inFIG. 1, in the power management system1, the HEMS controller10is able to be connected to a network600via a broadband router300. The network600may be a public network such as the Internet or a private network such as an intra-company network. The HEMS controller10is able to communicate with the communication terminal100via the network600.

The power management system1includes, as power sources, the alternating current power source11and the direct current power sources12and13. The direct current power source12is, for example, a solar cell panel. The direct current power source13is, for example, a storage battery. In the storage battery of the direct current power source13, a surplus of power generated by the solar cell panel of the direct current power source12and power fed from the alternating current power source11in a time zone, such as midnight, where a price of power is low, may be stored.

In the power management system1, the four household electric appliances14to17serve as load devices. As the household electric appliances14to17, any household electric appliances such as lighting equipment, a television receiver, an air conditioner, a washing machine, and a refrigerator are able to be applied. The number “four” of the household electric appliances inFIG. 1is a simple example. In a case where the invention according to the present embodiment is carried out, the number of the household electric appliances may be four or more or less. The household electric appliances14to17are basically operated with the direct current power, but are able to be operated also with the alternating current power by having AC (alternating current)-DC (direct current) converters18to21embedded therein, respectively.

Supply of the alternating current power (hereinafter, referred to as “alternating current power supply”) is performed from the alternating current power source11to the household electric appliances14to17through an alternating current power supply path22indicated by the thick dotted line. In the alternating current power supply path22, relays23to26are provided for the household electric appliances14to17on a one to one basis. The HEMS controller10controls the alternating current power supply for each of the household electric appliances14to17by opening or closing each of the relays23to26. Current sensors27to30are arranged in the individual alternating current power supply path22, in which the relays23to26are arranged, for the household electric appliances14to17. Note that, electric parts of a different type may be used instead of the relays23to26as long as switching is able to be performed through communication from the HEMS controller10. Any of wired communication (including power line communication) and wireless communication may be used to perform the communication. Similarly, any communication means may be used for the current sensors as long as a signal is able to be transmitted to the HEMS controller10.

A DC-DC converter31is connected to a path in which power is output from the direct current power source12. A DC-DC converter32is connected to a path in which power is output from the direct current power source13. Supply of the direct current power (hereinafter, referred to as “direct current power supply”) is performed from the DC-DC converters31and32to the household electric appliances14to17through a direct current power supply path33indicated by the thick solid line. In the direct current power supply path33, relays34to37are provided for the household electric appliances14to17on a one to one basis. The HEMS controller10controls the direct current power supply for each of the household electric appliances14to17by opening or closing each of the relays34to37. Current sensors38to41are arranged in the individual direct current power supply path33, in which the relays34to37are arranged, for the household electric appliances14to17. Current sensors42and43are provided also in a path in which each of the DC-DC converters31and32outputs power.

The alternating current power supply path22and the direct current power supply path33are connected to each other via an AC-DC converter44that is a system interconnection inverter. A current sensor45is arranged at a part where the AC-DC converter44is connected to the alternating current power supply path22and a current sensor46is arranged at a part where the AC-DC converter44is connected to the direct current power supply path33. A current sensor47is arranged at a part nearest to the alternating current power source11in the alternating current power supply path22.

InFIG. 1, command transmission systems from the HEMS controller10to the relays23to26, the relays34to37, and the AC-DC converter44are indicated by the thin solid line. Signal transmission systems from the current sensors27to30,38to41,42,43,45,46, and47to the HEMS controller10are indicated by the thin one dot chain line.

3. Configuration of HEMS Controller

FIG. 3is a block diagram illustrating a configuration of the HEMS controller10.

With reference toFIG. 3, the HEMS controller10includes an antenna701, a wireless communication unit702, an operation reception unit703, a storage unit704, a light-emission unit705, a wired communication unit706, and a control unit707.

The antenna701emits a signal, which is output from the HEMS controller10, in a form of a radio wave. The antenna701receives the radio wave from a space and provides the wireless communication unit702with a received signal.

The wireless communication unit702is a communication interface that performs modulation and demodulation processing or the like for transmitting and receiving a signal in order for the HEMS controller10to perform wireless communication with another communication device.

The HEMS controller10conforms to, for example, a wireless LAN (Local Area Network) standard or a standard of near field communication such as Bluetooth (registered trademark), and communicates with the household electric appliances14to17(refer toFIG. 1) in accordance with such a communication standard. The HEMS controller10and each of the household electric appliances14to17conform to a standard for performing a remote operation of the household electric appliance.

By communicating with each of the household electric appliances14to17, the HEMS controller10is able to receive information indicating that each of the household electric appliances14to17is in operation. In a case where a time to start an operation of each of the household electric appliances14to17is reserved, the HEMS controller10receives, from each of the household electric appliances14to17, information about a time zone in which the operation is to be performed. In addition, by communicating with the household electric appliances14to17, the HEMS controller10transmits an instruction to restrict at least a part of the operation to the household electric appliances14to17. Each of the household electric appliances14to17communicates with the HEMS controller10and stops or executes a function in accordance with the instruction from the HEMS controller10.

The operation reception unit703is constituted by an operation member, for example, such as a button for receiving an input operation, and receives an input operation of a user and outputs the received input operation to the control unit707.

The storage unit704is constituted by a flash memory, a RAM, or the like, and stores a program and data that are used by the HEMS controller10. In a certain aspect, the storage unit704stores operation information710, switching information720, and a program730. The operation information710is information indicating operations of the household electric appliances14to17and an example thereof will be described later with reference toFIG. 4. The switching information720is information for giving an instruction about whether to drive each of the household electric appliances14to17with the alternating current power or the direct current power, and an example thereof will be described later with reference toFIG. 6. The program730is a program executed by the control unit707, for example.

The light-emission unit705includes a light-emission member such as an LED (Light Emitting Diode). The light-emission unit705emits light under control of the control unit707to thereby notify the outside of the HEMS controller10of information. The HEMS controller10causes the light-emission unit705to emit light to thereby notify the outside, for example, that the HEMS controller10is in communication or that power failure occurs in a system.

The wired communication unit706is a communication interface that performs modulation and demodulation processing or the like in order for the HEMS controller10to perform communication with another communication device in a wired manner. The wired communication unit706is able to be connected to the broadband router300(refer to FIG.1).

The control unit707is constituted by a processor and controls an operation of the HEMS controller10by reading and executing a control program stored in the storage unit704. The control unit707is operated in accordance with the program to thereby implement functions as an operation information registration unit771, a supply source decision unit772, a switching instruction transmission unit773, and a switching information registration unit774.

The operation information registration unit771acquires information about the operation of each of the household electric appliances14to17from each of the household electric appliances14to17and registers the information in the storage unit704as operation information.

The supply source decision unit772decides a power supply source (the direct current power source12or13or the alternating current power source11) of each of the household electric appliances14to17. The supply source decision unit772decides the direct current power source12or13as the power supply source, for example, during the daytime in which a price of the alternating current power from the alternating current power source11is high. Moreover, the supply source decision unit772decides the alternating current power source11as the power supply source when a power generation amount of the direct current power source12is small, for example, on a rainy day and a remaining battery level of the direct current power source13is low.

The switching instruction transmission unit773instructs each of the relays23to26and the relays27to30to open or close a circuit so that the power supply source of each of the household electric appliances14to17is the power supply source decided by the supply source decision unit772.

Note that, in a case where the relays23to26and the relays27and30are respectively provided in the household electric appliances14to17, the switching instruction transmission unit773transmits an instruction of the power supply source to each of the household electric appliances14to17. In accordance with the instruction, each of the household electric appliances14to17switches open and close of (any of the relays23to26and any of the relays27to30) in each of the appliances and adjusts the power supply source with respect to each of the appliances.

The switching information registration unit774registers the power supply source of each of the household electric appliances14to17, which is decided by the supply source decision unit772, in the storage unit704as switching information.

4. Operation Information

FIG. 4illustrates an example of a data structure of the operation information710stored in the storage unit704of the HEMS controller10.

As illustrated inFIG. 4, in each of records in the operation information710, household electric appliance identification information711, an operation time712, operation content713, and power consumption714are associated with each other. Each of the records is transmitted, for example, from each of the household electric appliances14to17(refer toFIG. 1). Each of the household electric appliances14to17transmits a record of operation execution to the HEMS controller10. Upon reception of the record, the operation information registration unit771(refer toFIG. 3) of the HEMS controller10updates the operation information710by adding the record.

The household electric appliance identification information711is information for specifying each of the household electric appliances14to17. For example, “12345678 (air conditioner (1))” inFIG. 4specifies one air conditioner among the household electric appliances14to17.

The operation time712indicates a time at which a household electric appliance was operated. For example, “2015/5/5_17:00:00-19:00:00” inFIG. 4indicates that the household electric appliance was operated from 17:00:00 to 19:00:00 on May 5, 2015.

The operation content713indicates what operation was executed by the household electric appliance. For example, “cooling (low)” inFIG. 4indicates that a cooling operation with intensity “low” was executed.

The power consumption714indicates the power consumption in the household electric appliance indicating the operation content specified by the operation content713. For example, “100 W” registered correspondingly to the operation content of “cooling (low)” inFIG. 4indicates that the power consumption of the cooling operation with the intensity “low” is 100 W.

FIG. 5schematically illustrates an example of a sequence in which a record of operation execution is transmitted from each of the household electric appliances14to17to the HEMS controller10. As illustrated inFIG. 5, each of the household electric appliances14to17executes “state notification” to the HEMS controller10at a certain time interval (for example, per 15 minutes). The “state notification” is a view indicating what content of operation was executed. There is also a case where “state notification” is information indicating that an operation in execution was finished.

Upon reception of the “state notification” from each of the household electric appliances14to17, on the basis of information thereof, the operation information registration unit771(refer toFIG. 3) of the HEMS controller10generates a record for each of the household electric appliances illustrated inFIG. 4. For example, in accordance with receiving, as the “state notification”, from the household electric appliance specified by “12345678 (air conditioner (1))”, information indicating that an operation specified by “cooling (low)” was executed from 17:00:00 to 19:00:00 on May 5, 2015 and that the operation was finished at 19:00:00 on May 5, 2015, the operation information registration unit771generates a record related to “12345678 (air conditioner (1))” as illustrated inFIG. 4.

5. Switching Information

FIG. 6illustrates an example of a data structure of the switching information720stored in the storage unit704of the HEMS controller10.

As illustrated inFIG. 6, in each of records in the switching information720, household electric appliance identification information721, a time722, and instruction content723are associated with each other.

The household electric appliance identification information721specifies any of the household electric appliances14to17. The time722indicates a time at which information for designating the power supply source to the household electric appliance specified by the household electric appliance identification information721was output. The instruction content723indicates the designated power supply source.

For example, “AC to DC” indicates that the designated power supply source is the direct current power source12or the direct current power source13. “DC to AC” indicates that the designated power supply source is the alternating current power source11.

When setting (switching) the supply source of the power to be used as power for each of the household electric appliances14to17, the switching instruction transmission unit773(refer toFIG. 3) of the HEMS controller10instructs a corresponding relay of the relays23to26and the relays34to37to switch open and close, and gives an instruction to each of the household electric appliances14to17. When driving with the alternating current power, the household electric appliances14to17respectively drive the AC-DC converters18to21.

FIG. 7illustrates an example of a sequence in which an instruction of a power supply source is transmitted from the switching instruction transmission unit773(refer toFIG. 3) of the HEMS controller10to each of the household electric appliances14to17. As illustrated inFIG. 7, the HEMS controller10(switching instruction transmission unit773) transmits an instruction to set (switch) the supply source as a “switching instruction”. Upon reception of the instruction to set (switch) the supply source, each of the household electric appliances14to17transmits a “response” to the HEMS controller10. In accordance with transmitting the “switching instruction” to the household electric appliance and receiving the “response” from the corresponding household electric appliance, the switching information registration unit774generates a new record and adds the record to the switching information720.

6. Configuration of Household Electric Appliance

FIG. 8schematically illustrates an example of a hardware configuration of the household electric appliance14. As illustrated inFIG. 8, the household electric appliance14includes a control unit900, an antenna901, a wireless communication unit902, a function execution unit903, and an operation storage unit904.

The control unit900is, for example, a processor and controls an operation of the household electric appliance14by executing a program stored in a memory in a memory (not illustrated) inside the household electric appliance14.

The antenna901is used for communication with another device such as the HEMS controller10.

The wireless communication unit902is an example of a communication interface. The control unit900is connected to the network600(refer toFIG. 1) by using the wireless communication unit902and the antenna901and communicates with another device such as the HEMS controller10. Note that, the household electric appliance14may conform to a wireless LAN standard or a standard of near field communication such as Bluetooth (registered trademark) in some cases. In accordance with such a communication standard, the household electric appliance14may directly communicate with another device such as the HEMS controller10in some cases.

The function execution unit903executes an inherent function of the household electric appliance14. In a case of lighting equipment, the function execution unit903is, for example, an element that implements a function for causing a light-emission element to light up. In a case of an air conditioner, the function execution unit903is, for example, an element, such as a compressor and a control circuit thereof, that implements a function for cooling an article.

The operation storage unit904is a memory and stores content of an operation executed by the function execution unit903. For example, at timing when causing the function execution unit903to start an operation indicating new content, the control unit900causes the content to be stored in the operation storage unit904. The control unit900transmits the operation content, which is stored in the operation storage unit904, to the HEMS controller10as the “state notification” (refer toFIG. 5).

Schematic configurations of the household electric appliances15to17may be similar to the configuration of the household electric appliance14illustrated inFIG. 8.

7. Configuration of Communication Terminal

FIG. 9is a block diagram illustrating a configuration of the communication terminal100of the first embodiment.

As illustrated inFIG. 9, the communication terminal100includes an antenna101, a wireless communication unit111, a physical operation key131, a touch panel141, a display142, a power source control unit144, a battery145, a sound processing unit146, a microphone147, a speaker148, a storage unit150, and a control unit160.

The antenna101emits a signal, which is output from the communication terminal100, in a form of a radio wave. The antenna101receives the radio wave from a space and provides the wireless communication unit111with a received signal. In the present embodiment, the communication terminal100conforms to a plurality of wireless communication standards. As a communication scheme, there are W-CDMA (Wideband Code Division Multiple Access), LTE (Long Term Evolution), and other communication schemes. The communication terminal100conforms also to a wireless LAN standard such as IEEE (Institute of Electrical and Electronic Engineers) 802.11.

The wireless communication unit111performs modulation and demodulation processing or the like for transmitting and receiving a signal via the antenna101or the like in order for the communication terminal100to communicate with another wireless device. The wireless communication unit111is a communication module that includes a tuner, an RSSI (Received Signal Strength Indicator) calculation circuit, a CRC (Cyclic Redundancy Check) calculation circuit, a high frequency circuit, and the like. The wireless communication unit111performs modulation and demodulation or frequency conversion for a wireless signal transmitted or received by the communication terminal100and provides the control unit160with a received signal.

The physical operation key131is a physical input device and receives a pressing operation by the user. In response to the pressing operation by the user, the physical operation key131outputs a signal indicating operation content to the control unit160.

The storage unit150is constituted by, for example, a flash memory or the like, and stores data and a program that are used by the communication terminal100. In a certain aspect, the storage unit150stores a basic program151, an application program152, and data153. The basic program151is a program that is executed for the communication terminal100to implement a call function or the like. The application program152is a program that is executed for the communication terminal100to implement an additional operation. The additional operation includes display of information about the power consumption of a household electric appliance as illustrated inFIG. 2. The data153is various data that is used to execute a program in the communication terminal100.

The power source control unit144controls power supply to each circuit of the communication terminal100. The power source control unit144is, for example, an IC (Integrated Circuit) for power source control. The battery145is a supply source that supplies power to operate each circuit of the communication terminal100. The power from the battery145is supplied to each circuit under control of the power source control unit144. The sound processing unit146performs modulation and demodulation of a sound signal. The sound processing unit146modulates a signal given from the microphone147and provides the control unit160with a modulated signal. The sound processing unit146provides the speaker148with the sound signal. The sound processing unit146is realized by, for example, a processor for sound processing. The microphone147receives a sound input and provides the sound processing unit146with a sound signal corresponding to the sound input. The speaker148converts the sound signal provided from the sound processing unit146into sound and outputs the sound to the outside of the communication terminal100.

The control unit160reads a program stored in the storage unit150and executes a command included in the control program to thereby control an operation of the communication terminal100. The control unit160is, for example, a processor. Being operated in accordance with the program, the control unit160implements functions as an instruction reception unit161, a display control unit162, an operation information acquisition unit163, and a switching information acquisition unit164.

The instruction reception unit161receives an input for giving an instruction to display information about the power of the household electric appliance. The instruction may be an operation instruction with respect to the touch panel141, an instruction by a sound input with respect to the microphone147, or an operation instruction generated when a specific application program is executed.

The display control unit162is realized by, for example, the control unit160that executes a driver program of the display142and controls a display operation of the display142.

The operation information acquisition unit163acquires, from the HEMS controller10, operation information (refer toFIG. 4) of an appliance whose information about the power is to be displayed among the household electric appliances14to17.

The switching information acquisition unit164acquires, from the HEMS controller10, switching information (refer toFIG. 6) of the appliance whose information about the power is to be displayed among the household electric appliances14to17.

8. Display Processing

FIG. 10is a flowchart of processing executed in the communication terminal100to display information about consumption of the direct current power in each of the household electric appliances14to17. The processing is realized by, for example, a power management application installed on the communication terminal100.

With reference toFIG. 10, at step S10, the control unit160(refer toFIG. 9) of the communication terminal100receives an input for giving an instruction to present information about the power consumption of a household electric appliance. In an example, the instruction is input by an operation instruction with respect to the touch panel141. In another example, the instruction is input by sound with respect to the microphone147. In still another example, the instruction is input by an operation input generated by execution of a specific application program (for example, a timer function to display information about the power of the household electric appliance at 8:00 a.m. on the first day of every month). Then, the control is caused to proceed to step S20.

At step S20, the control unit160specifies a household electric appliance of a display target. Then, the control is caused to proceed to step S30.

Note that, in an example of step S20, the control unit160reads out information which is stored in the storage unit150in advance and specifies the household electric appliance of the display target. In another example, the control unit160receives an input of an instruction to specify the household electric appliance of the display target. An example of the input of the instruction will be described with reference toFIG. 11.

FIG. 11illustrates an example of a screen displayed on the display142by the power management application. A screen500ofFIG. 11is displayed to select an appliance having a display form of information about power.

The screen500includes buttons501to508for selecting the household electric appliance of the display target. Each of the buttons502to508corresponds to selection of each of household electric appliances (each of the household electric appliances14to17in the example indicated inFIG. 1) that constitute the power management system1. The button501corresponds to all the household electric appliances that constitute the power management system1. The control unit160specifies the household electric appliance of the display target in accordance with which button in the screen500is pressed.

With reference back toFIG. 10, the control unit160specifies a display target period at step S30. Then, the control is caused to proceed to step S40.

Note that, an example of the period specified at step S30is 1 month. Another example thereof is 1 year. Still another example thereof is 1 day. Still another example is a period till when step S30is executed after recording of data associated with the power consumption of a household electric appliance starts in the HEMS controller10.

Alternatively, at step S30, the control unit160specifies the display target period, for example, in accordance with a touch operation with respect to the touch panel141. More specifically, for example, when the household electric appliance of the display target is specified on the screen500ofFIG. 11, the screen510(refer toFIG. 2) is displayed on the display142. “Result of July 2013” is described in the center of the input unit513of the screen510. This means that the display target is July 2013. When a “previous month” button on a left end in the input unit513is touched, the control unit160specifies the previous month of July 2013, that is, June 2013 as the display target. When a “next month” button on a right end in the input unit513is touched, the control unit160specifies a next month of July 2013, that is, August 2013 as the display target.

In addition, at step S30, the control unit160specifies a length of the display target period, for example, in accordance with a touch operation with respect to the touch panel141. More specifically, in accordance with any of three buttons “24 hours”, “1 month”, and “1 year” in the input unit512of the screen510ofFIG. 2being touched, the control unit160specifies, as the length of the display target period, a period described in each of the buttons.

Note that, at step S30, there may be a case where the control unit160specifies the length of the display target period in accordance with data stored in the storage unit150or a period specified by another application being executed in the communication terminal100.

With reference back toFIG. 10, the control unit160calculates the consumption of the direct current power (DC power) of the target household electric appliance in the target period at step S40. Then, the control is caused to proceed to step S50.

Note that, at step S40, the target household electric appliance has been specified at step S20. The target period has been specified at step S30. The control unit160acquires operation information and switching information of the target appliance from the HEMS controller10. Then, on the basis of the switching information, the control unit160specifies an operation period with the direct current power in the target period. On the basis of the operation information, the control unit160specifies operation content in the specified operation period. The control unit160calculates an amount of power, which is required to perform an operation of the specified content, in the specified operation period. Then, the control unit160specifies the calculated amount of power as the consumption of the direct current power of the target household electric appliance in the target period. Here, the consumption in the target period is specified per certain period in the target period. For example, the consumption of 1 month is displayed day by day on the screen510ofFIG. 2. In this manner, the consumption in a predetermined period (for example, 1 month) is calculated per certain period (for example, 1 day).

With reference back toFIG. 10, the control unit160calculates the consumption of the alternating current power (AC power) of the target household electric appliance in the target period at step S50. Then, the control is caused to proceed to step S60.

Note that, at step S50, the control unit160calculates, per certain period, the consumption of the alternating current power of the household electric appliance of the display target in the display target period by using the operation information and the switching information that are acquired at step S40.

At step S60, by using the consumption of the direct current power, which is calculated at each of step S40and S50, the control unit160generates image data for display that is related to information about the power consumption as in the screen510ofFIG. 2. Here, as indicated with the graph511, for a predetermined period (1 month) as the display target, the consumption of each of the direct current power and the alternating current power of the household electric appliance of the display target is displayed per certain period (1 day). Then, the control is caused to proceed to step S70.

Note that, the generation of the image data for display at step S60includes calculation of numerical values corresponding to the “total usage” and the “reference cost” of the screen510ofFIG. 2. The “total usage” is a total value of the consumption of the direct current power and the alternating current power. The “reference cost” is a product of the consumption of the direct current power and a predefined unit cost for purchasing the alternating current power.

At step S70, the control unit160displays the image data generated at step S60(displays a history of the target period) on the display, and ends the processing ofFIG. 10.

9. Example of Another Display Screen

FIGS. 12 and 13are views each illustrating a modified example of a display screen for information about the power consumption. A screen520ofFIG. 12corresponds to a case where the predetermined period (display target period) is 24 hours. The screen520includes a graph521. In the graph521, a color of the graph is specified per certain period (15 minutes). In the graph521, a vertical axis indicates power consumption and a horizontal axis indicates a time. The certain period may be set as a time that is the same as a time interval at which each of the household electric appliances14to17transmits the “state notification” (refer toFIG. 5) to the HEMS controller10or that is obtained by adding a slight margin to the time interval.

InFIG. 12, the color of the graph is represented on the basis of a type of hatching. In each of 15-minute periods, when the direct current power has been used for a certain period (for example, 5 minutes) or more in the 15-minute period, the period is indicated in such a manner that the direct current power has been used for the full 15 minutes. That is, the graph521ofFIG. 12is displayed by deforming the consumption of the direct current power.

A screen530ofFIG. 13corresponds to a case where the predetermined period (display target period) is 1 month. The screen530includes a graph531. The graph531includes a plurality of bars indicating the consumption per certain period (1 month). In each of the bars, the consumption of the direct current power and the consumption of the alternating current power in the certain period are indicated in mutually different forms (types of hatching).

10. Summary of Embodiment

In the first embodiment described above, a load device that is operated by switching the power for driving between the alternating current power and the direct current power is constituted by each of the household electric appliances14to17. As described mainly with reference toFIG. 10, for the household electric appliance that is specified as the display target among the household electric appliances14to17, the communication terminal100generates image data for display (display information) that is related to information about the consumption of the direct current power.

A length of the display target period may be specified from a plurality of types. In the first embodiment, the length may be specified from, for example, three types of 1 year, 1 month, and 1 day. Note that, the three types of periods indicated here are merely illustrative. The communication terminal100may receive, from the user, information for specifying any length as the display target period.

In the first embodiment, the communication terminal100sets “1 month” as the display target in some cases (refer toFIG. 2) and sets “1 day” as the display target in other cases (refer toFIG. 12). When setting “1 day” as the display target, the communication terminal100displays the consumption per 15 minutes. In each of 15-minute periods, when the direct current power has been used for a certain period (for example, 5 minutes) or more in the 15-minute period, the period is indicated in such a manner that the direct current power has been used for the full 15 minutes.

Note that, in the display per 15 minutes, when the consumption of the direct current power occupies a certain proportion (for example, 30%) or more with respect to the consumption of the power in the 15-minute period, the period may be indicated in such a manner that the power consumption for 15 minutes is all the power consumption of the direct current power. That is, the display per 15 minutes may be performed by deforming a type of the power that is consumed.

When the display target period is “1 month” (FIG. 2), the image data for display includes data (a bar representing the consumption of each day in the graph511) indicating the daily consumption. In this sense, data for displaying the bar which represents the consumption of each day in the graph511is an example of “first display information”. The consumption of each day indicates the consumption of the direct current power of the day and the consumption of the alternating current power of the day.

When the display target period is “1 day” (FIG. 12), the image data for display includes data which indicates the consumption of the power per 15 minutes when 1 day as the display target is divided into each 15 minutes. In this sense, data of the graph521is an example of “second display information”.

11. Effect of Embodiment

It may be said that consuming the direct current power supplied from the direct current power source12or13in the power management system1of the first embodiment described above brings the following advantage for the user with respect to consuming the direct current power supplied from the commercial alternating current power source11.

That is, the direct current power source12that supplies the direct current power to a household electric appliance provides the user with power converted from a solar energy instead of the power purchased from the commercial alternating current power source11. Thereby, by using the power supplied from the direct current power source12, the user does not need to pay the power cost to a power company.

The direct current power source13stores the power supplied from the direct current power source12and the power supplied from the commercial alternating current power source11at low cost, for example, at night. This makes it possible to reduce the power cost that the user pays to the power company by using the power supplied from the direct current power source13.

It is also possible to enhance use efficiency of the power by operating an appliance with the direct current power without converting the direct current power supplied from the direct current power source12or13into the alternating current power. When the appliance is operated with the alternating current power, the alternating current power obtained by converting the direct current power supplied from the direct current power source12or13is used, so that a loss is caused due to the power conversion from the direct current power to the alternating current power. When the appliance is operated directly with the direct current power without converting the direct current power supplied from the direct current power source12or13into the alternating current power, there is no loss due to the conversion, thus making it possible to reduce the power consumption. As a result, operating the appliance with the direct current power exhibits an effect of reduction in the power consumption, and by displaying an amount of the power consumption, the effect of the reduction in the power consumption is able to be easily recognized. In other words, consuming the direct current power instead of the alternating current power brings high use efficiency of the power and reduction in the power consumption. Therefore, by performing display that the direct current power is consumed, it is possible to recognize that the effect of reduction in the power consumption is achieved.

In the first embodiment, the communication terminal100displays a screen such as the screen510ofFIG. 2by execution of the power management application of the power management system including household electric appliances. For example, in the graph511of the screen510ofFIG. 2, information about the consumption of the direct current power supplied from the direct current power source12or13for a household electric appliance is displayed. Thereby, the user acquires the information about the consumption of the direct current power supplied from the direct current power source12or13and is thus able to easily recognize an effect of reduction in the consumption of the alternating current power.

Second Embodiment

A hardware configuration of the power management system1of a second embodiment may be the same as that of the first embodiment. Note that, in comparison with the first embodiment, the control of step S50ofFIG. 10is omitted in the communication terminal100in the power management system1of the second embodiment. That is, in the second embodiment, only information about the consumption of the direct current power for a household electric appliance serving as a display target is displayed.

FIG. 14illustrates an example of display related to power consumption of a household electric appliance in the second embodiment. A screen510A ofFIG. 14corresponds to a modified example of the screen510ofFIG. 2. A graph511A is displayed on the screen510A ofFIG. 14. The graph511A indicates the consumption of only the direct current power of the household electric appliance in a target period.

Third Embodiment

A hardware configuration of the power management system1of a third embodiment may be the same as that of the first embodiment. In the third embodiment, however, the communication terminal100receives an input of a target value related to the consumption of the direct current power. In display of information about the consumption of the household electric appliance as illustrated inFIG. 2or the like, the communication terminal100displays whether or not the consumption of the direct current power achieves the target value, that is, whether or not the consumption reaches the target value or more.

FIG. 15is a block diagram illustrating a configuration of the communication terminal100in the power management system1of the third embodiment. As illustrated inFIG. 15, the communication terminal100of the third embodiment stores a target value154in the storage unit150, in comparison with the communication terminal100(refer toFIG. 9) of the first embodiment. The target value154is, for example, a target value for the consumption of the direct current power for 1 month for a specific household electric appliance of the household electric appliances14to17(refer toFIG. 1) or for all the household electric appliances of the power management system1. The user inputs the target value, for example, by operating the touch panel141. In response thereto, the instruction reception unit161stores the input target value in the storage unit150.

FIG. 16illustrates an example of display of information about power consumption of a household electric appliance in the communication terminal100of the third embodiment. A screen510B ofFIG. 16corresponds to a modified example of the screen510ofFIG. 2. On the screen510B ofFIG. 16, an icon515and a message516are displayed with the graph511. The screen510B is displayed when the target value is achieved. Thus, the message516includes a character string (“Monthly target is achieved!”) indicating that the target value is achieved. The icon515includes an image indicating delight with achievement of the target value.

Note that, when the target value is not achieved, a screen different from the screen510B is displayed on the display142. Such a screen indicates that the target value is not achieved in place of the message516and includes a message for encouraging to achieve the target value in a next period (for example, next month).

FIG. 17is a flowchart of processing executed in the communication terminal100of the third embodiment. The processing ofFIG. 17corresponds to a modified example of the processing ofFIG. 10in the first embodiment. More specifically, the processing ofFIG. 17includes step S52that is provided after step S50. In the third embodiment, the control is caused to proceed to step S52after step S50.

At step S52, the control unit160determines whether or not the consumption (calculated at step S30) of the direct current power of the household electric appliance of the display target in the display target period is equal to or greater than the target value154stored in the storage unit150to thereby determine whether or not the target value is achieved. Then, the control is caused to proceed to step S60.

At step S60, the control unit160generates image data for display in a similar manner to the first embodiment. The image data generated in the third embodiment includes data, such as the icon515or the message516ofFIG. 16, for displaying a result of determination about whether or not the target value is achieved.

Note that, an input of the “target value” in the present specification may be generated and stored in the storage unit150by an aspect other than an operation by the user, for example, by an output of an execution result of a different application. When the target value of the consumption of the direct current power for the household electric appliance is calculated, for example, as the result of execution of the different application, the control unit160may store the target value in the storage unit150.

In another example, the target value may be the “reference cost” that is referred to in association with the screen510ofFIG. 2. By dividing the “reference cost” that is registered as a target value by a predefined unit cost for purchasing the alternating current power, the control unit160is able to convert the target value of the “reference cost” into a target value of the consumption of the direct current power.

In still another example, the target value may be a target value of the consumption of the alternating current power. In this case, when the consumption of the alternating current power is equal to or smaller than the target value, it is determined that the target value is achieved. Thereby, the user may be notified that the consumption of the alternating current power is reduced due to an increase in the consumption of the direct current power.

Fourth Embodiment

A hardware configuration of the power management system1of a fourth embodiment may be the same as that of the third embodiment. In the fourth embodiment, the control unit160of the communication terminal100further receives an input of information for changing the target value stored in the storage unit150.

In the fourth embodiment, the target value for the consumption of the direct current power of a household electric appliance is stored in the storage unit150in association with a time at which the target value is stored in the storage unit150(or a time at which the target value is input). In the fourth embodiment, similarly to the third embodiment, the control unit160determines whether or not the consumption of the direct current power in the display target period is equal to or greater than the target value. Note that, in the fourth embodiment, the target value used for the determination is a target value stored being associated with a time before the display target period expires. A target value registered after the display target period expires is not used.

That is, for example, when information of the consumption of the direct current power for 1 month is displayed and when the display target period is changed in the course of the month, image data for display of the month is generated on the basis of the target value before the change. More specifically, when information of the power consumption of July is displayed and when the target value is changed on July 15, whether or not the target value of the power consumption of July is achieved is determined on the basis of the target value before the change.

Fifth Embodiment

In the power management system1of a fifth embodiment, image data for display, such as the screen510ofFIG. 2, related to the power consumption of a household electric appliance is generated in the HEMS controller10. That is, in the fifth embodiment, the HEMS controller10is an example of the power information management device. Upon reception of an instruction to display the power consumption, the communication terminal100requests the HEMS controller10to generate image data for display.

FIG. 18is a flowchart of processing executed by the communication terminal100in the fifth embodiment.

As illustrated inFIG. 18, the control unit160receives an input for giving an instruction to present information about the power consumption of a household electric appliance (step S10), specifies a household electric appliance of a display target (step S20), and specifies a display target period (step S30). Then, the control is caused to proceed to step S32.

At step S32, the control unit160requests the HEMS controller10to generate image data for display. To the HEMS controller10, the control unit160transmits, with the request, information of the household electric appliance specified at step S20and information indicating the period specified at step S30.

In accordance with the request, the HEMS controller10generates image data for display as described below and transmits the resultant to the communication terminal100. In response thereto, the control unit160receives the image data for display at step S34. Then, the control unit160displays the received image data (displays a history of the target period) at step S70.

FIG. 19is a block diagram illustrating a configuration of the HEMS controller10of the fifth embodiment. The block diagram ofFIG. 19corresponds to a modified example of the block diagram ofFIG. 3. In comparison withFIG. 3, a control unit707of the HEMS controller10further implements a function as a display information generation unit775as illustrated inFIG. 19.

FIG. 20is a flowchart of processing executed by the control unit707of the HEMS controller10of the fifth embodiment.

With reference toFIG. 20, at step S100, the control unit707receives the request (step S32ofFIG. 18) from the communication terminal100to generate image data. Then, the control is caused to proceed to step S110.

At step S110, similarly to step S40(refer toFIG. 10), the control unit707calculates the consumption of the direct current power (DC power) of the household electric appliance of the display target in the target period. Then, the control is caused to proceed to step S120.

At step S120, similarly to step S50(refer toFIG. 10), the control unit707calculates the consumption of the alternating current power (AC power) of the household electric appliance of the display target in the target period. Then, the control is caused to proceed to step S130.

At step S130, similarly to step S60(refer toFIG. 10), the control unit707generates image data for display. Then, the control is caused to proceed to step S140.

At step S140, the control unit707transmits the image data generated at step S130to the communication terminal100. The control unit160of the communication terminal100receives the image data at step S34(refer toFIG. 18).

In the fifth embodiment described above, even when an instruction to display information about the power consumption is given, the communication terminal100does not need to generate image data. The image data is generated by the HEMS controller10. This results in reduction in processing load of a processor that constitutes the control unit160of the communication terminal100.

Sixth Embodiment

As a sixth embodiment, a modified example of a management mode of operation information and switching information in the power management system1is indicated. While operation information and switching information are individually managed in the first embodiment, information corresponding to the operation information and the switching information is managed as “power consumption information” in the sixth embodiment.

1. Specific Example of Power Consumption Information

FIG. 21schematically illustrates an example of content of the power consumption information.

As illustrated inFIG. 21, each of records in power consumption information1000includes household electric appliance identification information1001, a notification time1002, integral AC power consumption1003, integral DC power consumption1004, and an integral DC time1005.

The household electric appliance identification information1001is information for specifying each of household electric appliances.

The notification time1002indicates a time at which the “state notification” (refer toFIG. 5) is received from each of the household electric appliances. That is, the HEMS controller10acquires each of the records in the power consumption information1000, for example, through the “state notification” from each of the household electric appliances14to17, which has been described with reference toFIG. 5. The notification time1002is a time at which the “state notification” is received.

The integral AC power consumption1003is an integral value of the consumption of the alternating current power in each of the household electric appliances transmitting the “state notification”. Each of the household electric appliances records an integral value of the consumption of the alternating current power in the household electric appliance and transmits the integral value to the HEMS controller10as the integral AC power consumption.

The integral DC power consumption1004is an integral value of the consumption of the direct current power in each of the household electric appliances transmitting the “state notification”. Each of the household electric appliances records an integral value of the consumption of the direct current power in the household electric appliance and transmits the integral value to the HEMS controller10as the integral DC power consumption.

The integral DC time1005is an integral value of a time during which the direct current power is consumed in each of the household electric appliances transmitting the “state notification”. Each of the household electric appliances records an integral value of a time during which the household electric appliance is driven with the direct current power and transmits the integral value to the HEMS controller10as the integral DC time.

2. Configuration of HEMS Controller

FIG. 22illustrates a configuration of the HEMS controller10of the sixth embodiment.

The HEMS controller10illustrated inFIG. 22is different from the HEMS controller10of the first embodiment illustrated inFIG. 3in terms of information stored in the storage unit704. Specifically, in the sixth embodiment, the storage unit704stores the power consumption information1000(refer toFIG. 21) instead of storing the operation information710and the switching information720ofFIG. 3.

3. Specific Example of Communication Device

FIG. 23is a block diagram illustrating a configuration of the communication terminal100of the sixth embodiment.

The communication terminal100illustrated inFIG. 23is different from the communication terminal100of the first embodiment illustrated inFIG. 9in terms of a function of the control unit160. More specifically, the control unit160of the control unit100of the sixth embodiment implements a function as an information acquisition unit163A instead of the functions as the operation information acquisition unit163and the switching information acquisition unit164.

The information acquisition unit163A is realized by the power management application installed on the communication terminal100. The information acquisition unit163A acquires, from the HEMS controller10, for example, information of a household electric appliance of a display target for information about the consumption of the direct current power.

More specifically, the information acquisition unit163A acquires, from the power consumption information (refer toFIG. 21), a record of the household electric appliance of the display target in a display target period. The information acquisition unit163A calculates a difference between an integral value of the consumption of the direct current power for the household electric appliance when the display target period ends and an integral value of the consumption thereof when the period starts and thereby calculates the consumption of the direct current power in the display target period.

For example, according to the power consumption information illustrated inFIG. 21, the consumption of the direct current power for the household electric appliance specified by “air conditioner (1)” for fifteen minutes from 13:00 to 13:15 on May 5, 2015 is calculated as 1000 Wh from the following expression (1).

In the expression (1), “43000 (Wh)” is the integral DC power consumption of the “air conditioner (1)” at 13:15 on May 5, 2015. “42000 (Wh)” is the integral DC power consumption of the “air conditioner (1)” at 13:00 on May 5, 2015.

Seventh Embodiment

A power management system of a seventh embodiment includes a plurality of household electric appliances. The plurality of household electric appliances include a household electric appliance that uses the alternating current power as a power source and a household electric appliance that uses the direct current power as a power source. The plurality of household electric appliances may include one that uses only the alternating current power as a driving source, one that uses the direct current power as a driving source, and one that uses both the alternating current power and the direct current power as a driving source. That is, the power management system of the seventh embodiment includes a plurality of household electric appliances that are operated with the alternating current power and the direct current power.

In the seventh embodiment, a power information management device acquires, for the plurality of household electric appliances, information for specifying the consumption of the direct current power and information for specifying the consumption of the alternating current power. Display information generated by the power information management device indicates, for the plurality of household electric appliances, the consumption of the direct current power altogether and the consumption of the alternating current power altogether. Note that, in the seventh embodiment, the consumption of the direct current power and the consumption of the alternating current power for the plurality of household electric appliances are displayed in different forms.

It is to be understood that the disclosed embodiments and modified examples thereof are only illustrative and not restrictive in all aspects. The scope of the disclosure is interpreted by the scope of the claims rather than the foregoing description, and it is intended that all kinds of variations are included in a meaning and a range equivalent to the claims.

A program executed in each of the embodiments described above may be stored in a storage device that is fixed to a hardware resource such as the HEMS controller10or the communication terminal100or may be stored in a recording medium that is attachable to or detachable from the hardware resource. The program may be executed by being downloaded on the hardware resource via a network or by a processor provided in each hardware resource in a state of being stored in a storage device, such as a server, on the network.

REFERENCE SIGNS LIST