Patent Publication Number: US-11658321-B2

Title: Energy management method, energy management apparatus, and energy management system

Description:
RELATED APPLICATIONS 
     The present application is a National Phase of International Application No. PCT/JP2018/013294, filed Mar. 29, 2018, and claims priority based on Japanese Patent Application No. 2017-064450, filed Mar. 29, 2017. 
     TECHNICAL FIELD 
     The present invention relates to an energy management method, an energy management apparatus, and an energy management system. 
     BACKGROUND ART 
     In the related art, a technology of controlling a fuel cell apparatus provided in each of a plurality of facilities is proposed (for example, Patent Literature 1). Specifically, a switch provided between the plurality of facilities is controlled such that output power of the fuel cell apparatus is interchanged between the plurality of facilities. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese application publication No. 2016-152659 
     SUMMARY OF INVENTION 
     An energy management method according to a first aspect comprises a step A of outputting, by a fuel cell apparatus provided in each of a plurality of facilities, power using fuel, a step B of managing a storage amount of the fuel stored in a storage tank shared by the plurality of facilities, and a step C of allocating the storage amount of the fuel to each of the plurality of facilities. 
     An energy management apparatus according to a second aspect comprises a manager configured to manage a storage amount of fuel which is used in power generation by a fuel cell apparatus provided in each of a plurality of facilities and is stored in a storage tank shared by the plurality of facilities, and a controller configured to allocate the storage amount of the fuel to each of the plurality of facilities. 
     An energy management system according to a third aspect comprises a fuel cell apparatus provided in each of a plurality of facilities, a storage tank shared by the plurality of facilities, and an energy management apparatus configured to manage a storage amount of fuel stored in the storage tank. The energy management apparatus is configured to allocate the storage amount of the fuel to each of the plurality of facilities. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a diagram illustrating an energy management system  100  according to an embodiment. 
         FIG.  2    is a diagram illustrating a facility  300  according to the embodiment. 
         FIG.  3    is a diagram illustrating a power management server  200  according to the embodiment. 
         FIG.  4    is a diagram illustrating a local control apparatus  360  according to the embodiment. 
         FIG.  5    is a diagram illustrating an energy management method according to the embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In a facility complex (for example, housing complex such as an apartment house) constituted by a plurality of facilities mentioned in the background art, a case in which a storage tank shared by a plurality of facilities is provided is considered. In such a case, when stagnation occurs in replenishment of fuel to the storage tank, or power outage occurs in a power grid, if the fuel (limited fuel) stored in the storage tank is arbitrarily used, a facility that saves the fuel and a facility that does not save the fuel are mixed, and thus there is a possibility of unfairness occurring between the plurality of facilities. 
     The present invention has been made to solve the above-described problem and provides an energy management method, an energy management apparatus, and an energy management system in which it is possible to secure fairness between a plurality of facilities. An embodiment will be described below with reference to the drawings. Regarding the following descriptions for the drawings, the same or similar reference signs are denoted by the same or similar components. 
     It should be noted that the drawings are schematic, and ratios and the like of dimensions may be different from actual ones. Thus, specific dimensions and the like should be determined in consideration of the following descriptions. In addition, it is noted that parts having different dimensional relationships or proportions between the drawings are included. 
     EMBODIMENT 
     Energy Management System 
     An energy management system according to an embodiment will be described below. 
     As illustrated in  FIG.  1   , an energy management system  100  includes a power management server  200 , a facility  300 , and a storage tank  400 .  FIG.  1    illustrates a facility  300 A to a facility  300 C as the facility  300 . 
     Each facility  300  is connected to a power grid  110 . In the following descriptions, a flow of electric power from the power grid  110  to the facility  300  is referred to as a power flow, and a flow of electric power from the facility  300  to the power grid  110  is referred to as a reverse power flow. 
     The power management server  200  and the facility  300  are connected to a network  120 . The network  120  may provide a line between the power management server  200  and the facility  300 . For example, the Internet is provided as the network  120 . The network  120  may provide a private line such as a virtual private network (VPN). 
     The power management server  200  is a server managed by a power company such as a power generation company, a power transmission and distribution company, or a retail company. 
     The power management server  200  transmits a control message of instructing a local control apparatus  360  provided in the facility  300  to control a distributed power supply (for example, solar cell apparatus, storage battery apparatus, and fuel cell apparatus) provided in the facility  300 . For example, the power management server  200  may transmit a power flow control message (for example, demand response (DR)) of requesting control of a power flow or may transmit a reverse power flow control message of requesting control of a reverse power flow. Further, the power management server  200  may transmit a power supply control message of controlling an operation state of the distributed power supply. The control degree of the power flow or the reverse power flow may be represented by an absolute value (for example, ∘∘ kW) or a relative value (for example, ∘∘%). The control degree of the power flow or the reverse power flow may be represented by two levels or more. The control degree of the power flow or the reverse power flow may be represented by electricity rates (RTP: real time pricing) defined by the current power supply and demand balance or by electricity rates (TOU: time of use) defined by the previous power supply and demand balance. 
     As illustrated in  FIG.  2   , the facility  300  includes a router  500 . The router  500  is connected to the power management server  200  via the network  120 . The router  500  constitutes a local area network and is connected to each apparatus (for example, PCS  331 , PCS  332 , PCS  333 , load  350  local control apparatus  360 , and the like). In  FIG.  2   , a solid line indicates a power line, and a dotted line indicates a signal line. The embodiment is not limited thereto, and a signal may be transmitted in the power line (for example, power-line transmission communication). 
     The facility  300  includes a solar cell  311 , a storage battery  312 , a fuel cell  313 , a hot-water supply apparatus  314 , a PCS  331 , a PCS  332 , a PCS  333 , a distribution board  340 , a load  350 , and the local control apparatus  360 . 
     The solar cell  311  is an apparatus that generates power with receiving light. The solar cell  311  outputs generated DC power. The generated energy of the solar cell  311  changes depending on the quantity of solar radiation with which the solar cell  311  is irradiated. 
     The storage battery  312  is an apparatus that stores electric power. The storage battery  312  outputs stored DC power. The storage battery  312  may be a power supply used in a virtual power plant (VPP). 
     The fuel cell  313  is a cell that outputs electric power using fuel. As the fuel, for example, a material containing hydrogen or a material containing alcohol may be provided. In addition, as the fuel, a material such as city gas, propane gas, kerosene, ammonia, or coal gas may be provided. For example, as the fuel cell  313 , any of a solid oxide fuel cell (SOFC), a polymer electrolyte fuel cell (PEFC), a phosphoric acid fuel cell (PAFC), and a molten carbonate fuel cell (MCFC) may be provided. 
     The hot-water supply apparatus  314  includes a hot-water storage tank. The hot-water supply apparatus  314  maintains or increases the amount of (hot) water stored in the hot-water storage tank or maintains or increases the temperature of (hot) water stored in the hot-water storage tank by using the waste heat of the fuel cell  313 . Such control may be referred to as boiling of water stored in the hot-water storage tank. 
     The PCS  331  refers to a power conditioning system (PCS) connected to the solar cell  311 . The PCS  331  converts DC power from the solar cell  311  into AC power. 
     The PCS  332  refers to a power conditioning system connected to the storage battery  312 . The PCS  332  converts DC power from the storage battery  312  into AC power and converts AC power for the storage battery  312  into DC power. 
     The PCS  333  refers to a power conditioning system connected to the fuel cell  313 . The PCS  333  converts DC power from the fuel cell  313  into AC power. 
     The distribution board  340  is connected to a main power line  10 L. The distribution board  340  includes a first distribution board  340 A and a second distribution board  340 B. The first distribution board  340 A is connected to a power grid  10  via a main power line  10 LA. The first distribution board  340 A is connected to the solar cell  311  via the PCS  331 , is connected to the storage battery  312  via the PCS  332 , and is connected to the fuel cell  313  via the PCS  333 . The first distribution board  340 A supplies electric power output from the PCS  331  to the PCS  333  and electric power supplied from the power grid  10 , to the second distribution board  340 B via a main power line  10 LB. The second distribution board  340 B distributes the electric power supplied via the main power line  10 LB, to each of equipments (here, load  350  and local control apparatus  360 ). 
     The load  350  refers to an apparatus that consumes electric power supplied via the power line. For example, the load  350  includes apparatuses such as an air conditioner, a lighting apparatus, a refrigerator, and a television. The load  350  may include a single apparatus or a plurality of apparatuses. 
     The local control apparatus  360  is an apparatus (EMS: energy management system) that manages electric power information indicating electric power in the facility  300 . The electric power in the facility  300  refers to electric power flowing in the facility  300 , electric power purchased by the facility  300 , or electric power sold from the facility  300 . Thus, the local control apparatus  360  manages at least the PCS  331  to the PCS  333 . 
     In the embodiment, the single solar cell  311  may be referred to as the solar cell apparatus, or the solar cell  311  and the PCS  331  may be referred to as the solar cell apparatus. The single fuel cell  313  may be referred to as the fuel cell apparatus. The fuel cell  313  and the PCS  333  may be referred to as the fuel cell apparatus. The fuel cell  313 , the hot-water supply apparatus  314 , and the PCS  333  may be referred to as the fuel cell apparatus. The single storage battery  312  may be referred to as the storage battery apparatus. The storage battery  312  and the PCS  332  may be referred to as the storage battery apparatus. 
     The storage tank  400  is a tank shared by the plurality of facilities  300  and a tank that stores the fuel. The fuel to be stored in the storage tank  400  may be regularly replenished by a fuel company or the like or may be replenished, if necessary, by the fuel company or the like. A timing at which the fuel is replenished may be scheduled. 
     In the embodiment, a communication between the power management server  200  and the local control apparatus  360  is performed in accordance with a first protocol. A communication between the local control apparatus  360  and the distributed power supply is performed in accordance with a second protocol different from the first protocol. As the first protocol, for example, a protocol based on Open ADR (automated demand response) (trademark) or an independent and dedicated protocol can be used. As the second protocol, for example, a protocol based on ECHONET Lite (registered trademark), SEP (Smart Energy Profile) 2.0, KNX, or an independent and dedicated protocol can be used. The first protocol and the second protocol may be different from each other. For example, even though both the first protocol and the second protocol are independent and dedicated protocols, the first protocol and the second protocol may be used so long as the first protocol and the second protocol are created with different rules. 
     Power Management Server 
     The power management server according to the embodiment will be described below. As illustrated in  FIG.  3   , the power management server  200  includes a manager  210 , a communicator  220 , and a controller  230 . The power management server  200  is an example of a virtual top node (VTN). 
     The manager  210  is constituted by a non-volatile memory and/or a storage medium such as an HDD and manages data regarding the facility  300 . As the data regarding the facility  300 , for example, the type of the distributed power supply provided in the facility  300  and the specifications of the distributed power supply provided in the facility  300  are provided. The specifications may include rated output power of the PCS  331  connected to the solar cell  311 , rated output power of the PCS  332  connected to the storage battery  312 , rated output power of the PCS  333  connected to the fuel cell  313 , and the like. 
     In the embodiment, the manager  210  manages at least the storage amount of the fuel stored in the storage tank  400 . The manager  210  may update the storage amount by storage amount data received from the storage tank  400 . The storage amount data may be data indicating an increased amount (replenished amount) of the fuel, data indicating a reduced amount (used amount) of the fuel, or data indicating the storage amount itself of the fuel. The data indicating the reduced amount (used amount) of the fuel may be received from the local control apparatus  360 . 
     The manager  310  may manage the remaining charge of the storage battery (storage battery apparatus)  313 . The manager  210  may update the remaining charge by remaining charge data received from the local control apparatus  360 . The remaining charge data may be data indicating an increased amount (charged amount) of the remaining charge, data indicating a reduced amount (discharged amount) of the remaining charge, or data indicating the remaining charge itself. 
     The communicator  220  is constituted by a communication module and communicates with the local control apparatus  360  via the network  120 . As described above, the communicator  220  performs communication in accordance with the first protocol. For example, the communicator  220  transmits a first message to the local control apparatus  360  in accordance with the first protocol. The communicator  220  receives a first message response from the local control apparatus  360  in accordance with the first protocol. 
     The controller  230  is constituted by a memory, a CPU, and the like and controls the components of the power management server  200 . For example, the controller  230  transmits a control message to instruct the local control apparatus  360  provided in the facility  300  to control the distributed power supply provided in the facility  300 . As described above, the control message may be a power flow control message, a reverse power flow control message, or a power supply control message. 
     In the embodiment, the controller  230  allocates the storage amount of the fuel to each of the plurality of facilities  300  in a predetermined period. The predetermined period may be at least one of a period in which stagnation occurs in replenishment of the fuel to the storage tank  400  and a period in which power outage occurs in the plurality of facilities  300 . 
     Here, the stagnation in replenishment of the fuel to the storage tank  400  may occur by a trouble of the fuel company or by a disaster. The power outage occurring in the plurality of facilities  300  may be power outage caused by a trouble of an electric power company or be power outage caused by a disaster. 
     The storage amount may be allocated to each of the plurality of facilities  300  in a manner as follows. In the following descriptions, a case in which, for example, three facilities  300  are provided as illustrated in  FIG.  1    will be described as an example. 
     (i) First Allocation Method 
     The controller  230  may allocate the storage amount of the fuel such that the amount of fuel allocated to each facility  300  becomes even. In such a case, the controller  230  allocates the storage amount of the fuel in accordance with the following expression, for example.
 
Allocation Amount of Facility 300 A= ⅓× X  
 
Allocation Amount of Facility 300 B= ⅓× X  
 
Allocation Amount of Facility 300 C= ⅓× X   [Expression 1]
 
     According to the first allocation method, it is possible to cause the output electric energy of the fuel cell apparatus to become uniform between the plurality of facilities  300 . The first allocation method is useful in a case where the output power of the fuel cell apparatus provided in the facility  300  can be controlled. In such a case, since the output power of the fuel cell apparatus in each facility  300  is controlled to have a predetermined value, it is possible to cause the output electric energy of the fuel cell apparatus to become uniform between the plurality of facilities  300 , and to cause an output time of the fuel cell apparatus to become uniform between the plurality of facilities  300 . 
     (ii) Second Allocation Method 
     The controller  230  may allocate the storage amount of the fuel based on a history of power consumption of each of the plurality of facilities  300 . For example, the controller  230  may allocate the storage amount more than that for the facility  300  having relatively small power consumption, to the facility  300  having relatively large power consumption. 
     Specifically, considered is a case where an average value of power consumption of the facility  300 A is A 2  (kW), an average value of power consumption of the facility  300 B is B 2  (kW), an average value of power consumption of the facility  300 C is C 2  (kW), and the storage amount of the storage tank  400  is X (m 3 ). In such a case, the controller  230  allocates the storage amount of the fuel in accordance with the following expression, for example. 
     
       
         
           
             
               
                 
                   
                     
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     According to the second allocation method, since the history of power consumption is considered, it is possible to reduce an influence on a user before and after a start of the predetermined period. 
     (iii) Third Allocation Method 
     The controller  230  may allocate the storage amount of the fuel based on rated output power of the fuel cell apparatus provided in each of the plurality of facilities  300 . For example, the controller  230  may allocate the storage amount more than that for the facility  300  including the fuel cell apparatus having relatively small rated output power, to the facility  300  including the fuel cell apparatus having relatively large rated output power. 
     Specifically, considered is a case where rated output power of the fuel cell apparatus in the facility  300 A is A 3  (kW), rated output power of the fuel cell apparatus in the facility  300 B is B 3  (kW), rated output power of the fuel cell apparatus in the facility  300 C is C 3  (kW), and the storage amount of the storage tank  400  is X (m 3 ). In such a case, the controller  230  allocates the storage amount of the fuel in accordance with the following expression, for example. 
     
       
         
           
             
               
                 
                   
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     According to the third allocation method, in a case where the fuel cell apparatus provided in the facility  300  is configured to output rate power, it is possible to cause the output time of the fuel cell apparatus to become uniform between the plurality of facilities  300 . 
     (iv) Fourth Allocation Method 
     The controller  230  may allocate the storage amount of the fuel based on the remaining charge of the storage battery apparatus provided in one or more facilities  300  among the plurality of facilities  300 . For example, the controller  230  may allocate the storage amount more than that for the facility  300  including the storage battery apparatus having a relatively large remaining charge, to the facility  300  including the storage battery apparatus having a relatively small remaining charge. 
     Specifically, considered is a case where the remaining charge of the storage battery apparatus in the facility  300 A is A 4  (kWh), the remaining charge of the storage battery apparatus in the facility  300 B is B 4  (kWh), the remaining charge of the storage battery apparatus in the facility  300 C is C 4  (kWh), and the storage amount of the storage tank  400  is X (m 3 ). In such a case, the controller  230  allocates the storage amount of the fuel in accordance with the following expression, for example. 
     
       
         
           
             
               
                 
                   
                     
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     Here, regarding the facility  300  in which the remaining charge of the storage battery apparatus is zero or the facility  300  which does not include the storage battery apparatus, a constant (integer larger than zero) may be substituted instead of the inverse of the remaining charge. Such a constant may be determined in accordance with the remaining charge of the storage battery apparatus provided in other facilities  300 . 
     According to the fourth allocation method, since the remaining charge of the storage battery apparatus is considered, it is possible to reduce the sense of unfairness between the plurality of facilities  300  in terms of electric power output from both the fuel cell apparatus and the storage battery apparatus. 
     (v) Fifth Allocation Method 
     The controller  230  may allocate the storage amount of the fuel based on the power generation prediction amount of the solar cell apparatus provided in one or more facilities  300  among the plurality of facilities  300 . For example, the controller  230  may allocate the storage amount more than that for the facility  300  including the solar cell apparatus having a relatively large power generation prediction amount, to the facility  300  including the solar cell apparatus having a relatively small power generation prediction amount. 
     Here, the power generation prediction amount refers to electric energy having a possibility of the solar cell apparatus generating electric power in a calculation target period. The calculation target period may be equal to or shorter than the predetermined period. The power generation prediction amount may be calculated based on rated generated power of the solar cell apparatus. The power generation prediction amount may be calculated based on the rated generated power of the solar cell apparatus and meteorological data (quantity of solar radiation). 
     Specifically, considered is a case where the power generation prediction amount of the solar cell apparatus in the facility  300 A is A 5  (kWh), the power generation prediction amount of the solar cell apparatus in the facility  300 B is B 5  (kWh), the power generation prediction amount of the solar cell apparatus in the facility  300 C is C 5  (kWh), and the storage amount of the storage tank  400  is X (m 3 ). In such a case, the controller  230  allocates the storage amount of the fuel in accordance with the following expression, for example. 
     
       
         
           
             
               
                 
                   
                     
                       Allocation 
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                       Amount 
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                       of 
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                       300 
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     Here, regarding the facility  300  in which the power generation prediction amount of the solar cell apparatus is zero or the facility  300  which does not include the solar cell apparatus, a constant (integer larger than zero) may be substituted instead of the inverse of the power generation prediction amount. Such a constant may be determined in accordance with the power generation prediction amount of the solar cell apparatus provided in other facilities  300 . 
     According to the fifth allocation method, since the power generation prediction amount of the solar cell apparatus is considered, it is possible to reduce the sense of unfairness between the plurality of facilities  300  in terms of electric power output from both the fuel cell apparatus and the solar cell apparatus. 
     (vi) Sixth Allocation Method 
     The controller  230  may allocate the storage amount of the fuel based on a timing at which replenishment of the fuel to the storage tank  400  is resumed (hereinafter, resuming timing). For example, the controller  230  may allocate the storage amount of the fuel such that the total output power of the distributed power supply becomes even between the facilities  300  in a period from an allocation timing of the storage amount to the resuming timing (hereinafter, fuel replenishment stagnation period). 
     The sixth allocation method is a method considering the resuming timing in a combination of the fourth allocation method and the fifth allocation method. Here, in the sixth allocation method, the calculation target period used in the fifth allocation method corresponds to the fuel replenishment stagnation period. 
     The sixth allocation method is useful in a case in which the fuel replenishment stagnation period is long (for example, one week). That is, in the case in which the fuel replenishment stagnation period is long, the remaining charge of the storage battery apparatus is reduced, but the power generation of the solar cell apparatus continues so long as light receiving is possible. Focusing on this point, the resuming timing is considered in the sixth allocation method. 
     Local Control Apparatus 
     The local control apparatus according to the embodiment will be described below. As illustrated in  FIG.  4   , the local control apparatus  360  includes a first communicator  361 , a second communicator  362 , and a controller  363 . The local control apparatus  360  is an example of a virtual end node (VEN). 
     The first communicator  361  is constituted by a communication module and communicates with the power management server  200  via the network  120 . As described above, the first communicator  361  performs communication in accordance with the first protocol. For example, the first communicator  361  receives the first message from the power management server  200  in accordance with the first protocol. The first communicator  361  transmits the first message response to the power management server  200  in accordance with the first protocol. 
     The second communicator  362  is constituted by a communication module and communicates with the distributed power supply (for example, PCS  331  to PCS  333 ). As described above, the second communicator  362  performs communication in accordance with the second protocol. For example, the second communicator  362  transmits a second message to the distributed power supply in accordance with the second protocol. The second communicator  362  receives a second message response from the distributed power supply in accordance with the second protocol. 
     The controller  363  is constituted by a memory, a CPU, and the like and controls the components of the local control apparatus  360 . Specifically, in order to control electric power of the facility  300 , the controller  363  transmits the second message and receives the second message response so as to instruct the equipment to set the operation state of the distributed power supply. In order to manage electric power of the facility  300 , the controller  363  may transmit the second message and receive the second message response so as to instruct the distributed power supply to report information of the distributed power supply. 
     Energy Management Method 
     The energy management method according to the embodiment will be described below. An operation of the power management server  200  will be described below. 
     As illustrated in  FIG.  5   , in Step S 10 , the power management server  200  determines whether or not the current time point is in the predetermined period. In other words, the power management server  200  determines whether or not stagnation occurs in replenishment of the fuel to the storage tank  400  and whether or not power outage occurs in the plurality of facilities  300 . In a case where the current time point is in the predetermined period, the power management server  300  performs the process of Step S 11 . In a case where the current time point is not in the predetermined period, the power management server  300  ends a series of processes. 
     In Step S 11 , the power management server  200  allocates the storage amount of the fuel to each of the plurality of facilities  300 . For example, any of the first allocation method to the sixth allocation method described above is provided as a method of allocating the storage amount. 
     Actions and Advantageous Effects 
     In the embodiment, the power management server  200  allocates the storage amount of the fuel to each of the plurality of facilities  300  in the predetermined period. The predetermined period may be at least one of a period in which stagnation occurs in replenishment of the fuel to the storage tank  400  and a period in which power outage occurs in the plurality of facilities  300 . Thus, it is possible to suppress an occurrence of a situation in which the fuel is arbitrarily used by the facility  300  in such a predetermined period and to secure fairness between the plurality of facilities  300 . 
     Modification Example 1 
     Modification Example 1 of the embodiment will be described below. Descriptions will be made below focusing on differences from the embodiment. 
     In Modification Example 1, a fuel cell apparatus provided in each of a plurality of facilities  300  outputs electric power based on a storage amount allocated by a power management server  200 . For example, the fuel cell apparatus in each facility  300  controls the output power to have a predetermined value in a case where the storage amount is allocated by the above-described first allocation method. The fuel cell apparatus in each facility  300  controls the output power to be rate power in a case where the storage amount is allocated by the above-described third allocation method. 
     Other Embodiments 
     Although the present invention has been described by the above-described embodiment, it should not be understood that the descriptions and the drawings that form a part of this disclosure limit the present invention. Various alternative embodiments, examples, and operation techniques will be apparent to those skilled in the art from this disclosure. 
     In the embodiment, a case where the power management server  200  is an energy management apparatus that allocates the storage amount of the fuel stored in the storage tank  400  is exemplified. However, the embodiment is not limited thereto. For example, the energy management apparatus may correspond to one or more local control apparatuses  360  provided in the plurality of facilities  300 . The energy management apparatus may be a server or an apparatus provided separately from the power management server  200 . Such a server or an apparatus may be managed by the fuel company or by other companies. 
     Although not particularly mentioned in the embodiment, the local control apparatus  360  to be provided in the facility  300  may not necessarily be provided in the facility  300 . For example, some of the functions of the local control apparatus  360  may be provided by a cloud server provided on the Internet. That is, it may be considered that the local control apparatus  360  includes the cloud server. 
     Although not particularly mentioned in the embodiment, power generation efficiency of the fuel cell apparatus may be considered in a method of allocating the storage amount of the fuel (first allocation method to sixth allocation method). In such a case, the power management server  200  may allocate the storage amount more than that for the facility  300  including the fuel cell apparatus having relatively high power generation efficiency, to the facility  300  including the fuel cell apparatus having relatively low power generation efficiency. 
     Although not particularly mentioned in the embodiment, priority of allocating the storage amount of the fuel may be determined by the type of the facility  300 . For example, a case where a hospital, a corner store, and a bookstore are provided as the plurality of facilities  300  is considered. In such a case, first priority being the highest may be assigned to the hospital, second priority lower than the first priority may be assigned to the corner store, and third priority lower than the second priority may be assigned to the bookstore. As the priority becomes higher, the allocated amount of the storage amount of the fuel increases. The high priority is assigned to the facility  300  having a high degree of urgency. Thus, it is possible to allocate the large storage amount of the fuel to the facility  300  having a high degree of urgency. 
     In the embodiment, a case where the first protocol is a protocol based on Open ADR2.0, and the second protocol is a protocol based on ECHONET Lite is exemplified. However, the embodiment is not limited thereto. As the first protocol, a protocol standardized as a protocol used in communication between the power management server  200  and the local control apparatus  360  may be provided. As the second protocol, a protocol standardized as a protocol used in the facility  300  may be provided. 
     The entire content of Japanese Patent Application No. 2017-064450 (filed on Mar. 29, 2017) is incorporated herein by reference.