Patent Description:
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 <NUM>). 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.

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.

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.

An energy management system according to an embodiment will be described below.

As illustrated in <FIG>, an energy management system <NUM> includes a power management server <NUM>, a facility <NUM>, and a storage tank <NUM>. <FIG> illustrates a facility 300A to a facility 300C as the facility <NUM>.

Each facility <NUM> is connected to a power grid <NUM>. In the following descriptions, a flow of electric power from the power grid <NUM> to the facility <NUM> is referred to as a power flow, and a flow of electric power from the facility <NUM> to the power grid <NUM> is referred to as a reverse power flow.

The power management server <NUM> and the facility <NUM> are connected to a network <NUM>. The network <NUM> may provide a line between the power management server <NUM> and the facility <NUM>. For example, the Internet is provided as the network <NUM>. The network <NUM> may provide a private line such as a virtual private network (VPN).

The power management server <NUM> 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 <NUM> transmits a control message of instructing a local control apparatus <NUM> provided in the facility <NUM> to control a distributed power supply (for example, solar cell apparatus, storage battery apparatus, and fuel cell apparatus) provided in the facility <NUM>. For example, the power management server <NUM> 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 <NUM> 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>, the facility <NUM> includes a router <NUM>. The router <NUM> is connected to the power management server <NUM> via the network <NUM>. The router <NUM> constitutes a local area network and is connected to each apparatus (for example, PCS <NUM>, PCS <NUM>, PCS <NUM>, load <NUM> local control apparatus <NUM>, and the like). In <FIG>, 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 <NUM> includes a solar cell <NUM>, a storage battery <NUM>, a fuel cell <NUM>, a hot-water supply apparatus <NUM>, a PCS <NUM>, a PCS <NUM>, a PCS <NUM>, a distribution board <NUM>, a load <NUM>, and the local control apparatus <NUM>.

The solar cell <NUM> is an apparatus that generates power with receiving light. The solar cell <NUM> outputs generated DC power. The generated energy of the solar cell <NUM> changes depending on the quantity of solar radiation with which the solar cell <NUM> is irradiated.

The storage battery <NUM> is an apparatus that stores electric power. The storage battery <NUM> outputs stored DC power. The storage battery <NUM> may be a power supply used in a virtual power plant (VPP).

The fuel cell <NUM> 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 (see http://www. jp/news/press/AA5_100580. html) may be provided. For example, as the fuel cell <NUM>, 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 <NUM> includes a hot-water storage tank. The hot-water supply apparatus <NUM> 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 <NUM>. Such control may be referred to as boiling of water stored in the hot-water storage tank.

The PCS <NUM> refers to a power conditioning system (PCS) connected to the solar cell <NUM>. The PCS <NUM> converts DC power from the solar cell <NUM> into AC power.

The PCS <NUM> refers to a power conditioning system connected to the storage battery <NUM>. The PCS <NUM> converts DC power from the storage battery <NUM> into AC power and converts AC power for the storage battery <NUM> into DC power.

The PCS <NUM> refers to a power conditioning system connected to the fuel cell <NUM>. The PCS <NUM> converts DC power from the fuel cell <NUM> into AC power.

The distribution board <NUM> is connected to a main power line <NUM>. The distribution board <NUM> includes a first distribution board 340A and a second distribution board 340B. The first distribution board 340A is connected to a power grid <NUM> via a main power line 10LA. The first distribution board 340A is connected to the solar cell <NUM> via the PCS <NUM>, is connected to the storage battery <NUM> via the PCS <NUM>, and is connected to the fuel cell <NUM> via the PCS <NUM>. The first distribution board 340A supplies electric power output from the PCS <NUM> to the PCS <NUM> and electric power supplied from the power grid <NUM>, to the second distribution board 340B via a main power line 10LB. The second distribution board 340B distributes the electric power supplied via the main power line 10LB, to each of equipments (here, load <NUM> and local control apparatus <NUM>).

The load <NUM> refers to an apparatus that consumes electric power supplied via the power line. For example, the load <NUM> includes apparatuses such as an air conditioner, a lighting apparatus, a refrigerator, and a television. The load <NUM> may include a single apparatus or a plurality of apparatuses.

The local control apparatus <NUM> is an apparatus (EMS: energy management system) that manages electric power information indicating electric power in the facility <NUM>. The electric power in the facility <NUM> refers to electric power flowing in the facility <NUM>, electric power purchased by the facility <NUM>, or electric power sold from the facility <NUM>. Thus, the local control apparatus <NUM> manages at least the PCS <NUM> to the PCS <NUM>.

In the embodiment, the single solar cell <NUM> may be referred to as the solar cell apparatus, or the solar cell <NUM> and the PCS <NUM> may be referred to as the solar cell apparatus. The single fuel cell <NUM> may be referred to as the fuel cell apparatus. The fuel cell <NUM> and the PCS <NUM> may be referred to as the fuel cell apparatus. The fuel cell <NUM>, the hot-water supply apparatus <NUM>, and the PCS <NUM> may be referred to as the fuel cell apparatus. The single storage battery <NUM> may be referred to as the storage battery apparatus. The storage battery <NUM><NUM> and the PCS <NUM> may be referred to as the storage battery apparatus.

The storage tank <NUM> is a tank shared by the plurality of facilities <NUM> and a tank that stores the fuel. The fuel to be stored in the storage tank <NUM> 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 <NUM> and the local control apparatus <NUM> is performed in accordance with a first protocol. A communication between the local control apparatus <NUM> 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) <NUM>, 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.

The power management server according to the embodiment will be described below. As illustrated in <FIG>, the power management server <NUM> includes a manager <NUM>, a communicator <NUM>, and a controller <NUM>. The power management server <NUM> is an example of a virtual top node (VTN).

The manager <NUM> is constituted by a non-volatile memory and/or a storage medium such as an HDD and manages data regarding the facility <NUM>. As the data regarding the facility <NUM>, for example, the type of the distributed power supply provided in the facility <NUM> and the specifications of the distributed power supply provided in the facility <NUM> are provided. The specifications may include rated output power of the PCS <NUM> connected to the solar cell <NUM>, rated output power of the PCS <NUM> connected to the storage battery <NUM>, rated output power of the PCS <NUM> connected to the fuel cell <NUM>, and the like.

In the embodiment, the manager <NUM> manages at least the storage amount of the fuel stored in the storage tank <NUM>. The manager <NUM> may update the storage amount by storage amount data received from the storage tank <NUM>. 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 <NUM>.

The manager <NUM> may manage the remaining charge of the storage battery (storage battery apparatus) <NUM>. The manager <NUM> may update the remaining charge by remaining charge data received from the local control apparatus <NUM>. 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 <NUM> is constituted by a communication module and communicates with the local control apparatus <NUM> via the network <NUM>. As described above, the communicator <NUM> performs communication in accordance with the first protocol. For example, the communicator <NUM> transmits a first message to the local control apparatus <NUM> in accordance with the first protocol. The communicator <NUM> receives a first message response from the local control apparatus <NUM> in accordance with the first protocol.

The controller <NUM> is constituted by a memory, a CPU, and the like and controls the components of the power management server <NUM>. For example, the controller <NUM> transmits a control message to instruct the local control apparatus <NUM> provided in the facility <NUM> to control the distributed power supply provided in the facility <NUM>. 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 <NUM> allocates the storage amount of the fuel to each of the plurality of facilities <NUM> 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 <NUM> and a period in which power outage occurs in the plurality of facilities <NUM>.

Here, the stagnation in replenishment of the fuel to the storage tank <NUM> may occur by a trouble of the fuel company or by a disaster. The power outage occurring in the plurality of facilities <NUM> 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 <NUM> in a manner as follows. In the following descriptions, a case in which, for example, three facilities <NUM> are provided as illustrated in <FIG> will be described as an example.

The controller <NUM> may allocate the storage amount of the fuel such that the amount of fuel allocated to each facility <NUM> becomes even. In such a case, the controller <NUM> allocates the storage amount of the fuel in accordance with the following expression, for example.

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 <NUM>. The first allocation method is useful in a case where the output power of the fuel cell apparatus provided in the facility <NUM> can be controlled. In such a case, since the output power of the fuel cell apparatus in each facility <NUM> 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 <NUM>, and to cause an output time of the fuel cell apparatus to become uniform between the plurality of facilities <NUM>.

The controller <NUM> may allocate the storage amount of the fuel based on a history of power consumption of each of the plurality of facilities <NUM>. For example, the controller <NUM> may allocate the storage amount more than that for the facility <NUM> having relatively small power consumption, to the facility <NUM> having relatively large power consumption.

Specifically, considered is a case where an average value of power consumption of the facility 300A is A<NUM> (kW), an average value of power consumption of the facility 300B is B<NUM> (kW), an average value of power consumption of the facility 300C is C<NUM> (kW), and the storage amount of the storage tank <NUM> is X (m<NUM>). In such a case, the controller <NUM> allocates the storage amount of the fuel in accordance with the following expression, for example.

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.

The controller <NUM> 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 <NUM>. For example, the controller <NUM> may allocate the storage amount more than that for the facility <NUM> including the fuel cell apparatus having relatively small rated output power, to the facility <NUM> 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 300A is A<NUM> (kW), rated output power of the fuel cell apparatus in the facility 300B is B<NUM> (kW), rated output power of the fuel cell apparatus in the facility 300C is C<NUM> (kW), and the storage amount of the storage tank <NUM> is X (m<NUM>). In such a case, the controller <NUM> allocates the storage amount of the fuel in accordance with the following expression, for example.

According to the third allocation method, in a case where the fuel cell apparatus provided in the facility <NUM> 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 <NUM>.

The controller <NUM> may allocate the storage amount of the fuel based on the remaining charge of the storage battery apparatus provided in one or more facilities <NUM> among the plurality of facilities <NUM>. For example, the controller <NUM> may allocate the storage amount more than that for the facility <NUM> including the storage battery apparatus having a relatively large remaining charge, to the facility <NUM> 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 300A is A<NUM> (kWh), the remaining charge of the storage battery apparatus in the facility 300B is B<NUM> (kWh), the remaining charge of the storage battery apparatus in the facility 300C is C<NUM> (kWh), and the storage amount of the storage tank <NUM> is X (m<NUM>). In such a case, the controller <NUM> allocates the storage amount of the fuel in accordance with the following expression, for example.

Here, regarding the facility <NUM> in which the remaining charge of the storage battery apparatus is zero or the facility <NUM> 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 <NUM>.

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 <NUM> in terms of electric power output from both the fuel cell apparatus and the storage battery apparatus.

The controller <NUM> 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 <NUM> among the plurality of facilities <NUM>. For example, the controller <NUM> may allocate the storage amount more than that for the facility <NUM> including the solar cell apparatus having a relatively large power generation prediction amount, to the facility <NUM> 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 300A is As (kWh), the power generation prediction amount of the solar cell apparatus in the facility 300B is B<NUM> (kWh), the power generation prediction amount of the solar cell apparatus in the facility 300C is C<NUM> (kWh), and the storage amount of the storage tank <NUM> is X (m<NUM>). In such a case, the controller <NUM> allocates the storage amount of the fuel in accordance with the following expression, for example.

Here, regarding the facility <NUM> in which the power generation prediction amount of the solar cell apparatus is zero or the facility <NUM> 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 <NUM>.

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 <NUM> in terms of electric power output from both the fuel cell apparatus and the solar cell apparatus.

The controller <NUM> may allocate the storage amount of the fuel based on a timing at which replenishment of the fuel to the storage tank <NUM> is resumed (hereinafter, resuming timing). For example, the controller <NUM> may allocate the storage amount of the fuel such that the total output power of the distributed power supply becomes even between the facilities <NUM> 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.

The local control apparatus according to the embodiment will be described below. As illustrated in <FIG>, the local control apparatus <NUM> includes a first communicator <NUM>, a second communicator <NUM>, and a controller <NUM>. The local control apparatus <NUM> is an example of a virtual end node (VEN).

The first communicator <NUM> is constituted by a communication module and communicates with the power management server <NUM> via the network <NUM>. As described above, the first communicator <NUM> performs communication in accordance with the first protocol. For example, the first communicator <NUM> receives the first message from the power management server <NUM> in accordance with the first protocol. The first communicator <NUM> transmits the first message response to the power management server <NUM> in accordance with the first protocol.

The second communicator <NUM> is constituted by a communication module and communicates with the distributed power supply (for example, PCS <NUM> to PCS <NUM>). As described above, the second communicator <NUM> performs communication in accordance with the second protocol. For example, the second communicator <NUM> transmits a second message to the distributed power supply in accordance with the second protocol. The second communicator <NUM> receives a second message response from the distributed power supply in accordance with the second protocol.

The controller <NUM> is constituted by a memory, a CPU, and the like and controls the components of the local control apparatus <NUM>. Specifically, in order to control electric power of the facility <NUM>, the controller <NUM> 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 <NUM>, the controller <NUM> 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.

The energy management method according to the embodiment will be described below. An operation of the power management server <NUM> will be described below.

As illustrated in <FIG>, in Step S10, the power management server <NUM> determines whether or not the current time point is in the predetermined period. In other words, the power management server <NUM> determines whether or not stagnation occurs in replenishment of the fuel to the storage tank <NUM> and whether or not power outage occurs in the plurality of facilities <NUM>. In a case where the current time point is in the predetermined period, the power management server <NUM> performs the process of Step S11. In a case where the current time point is not in the predetermined period, the power management server <NUM> ends a series of processes.

In Step S11, the power management server <NUM> allocates the storage amount of the fuel to each of the plurality of facilities <NUM>. 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.

In the embodiment, the power management server <NUM> allocates the storage amount of the fuel to each of the plurality of facilities <NUM> 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 <NUM> and a period in which power outage occurs in the plurality of facilities <NUM>. Thus, it is possible to suppress an occurrence of a situation in which the fuel is arbitrarily used by the facility <NUM> in such a predetermined period and to secure fairness between the plurality of facilities <NUM>.

Modification Example <NUM> of the embodiment will be described below. Descriptions will be made below focusing on differences from the embodiment.

In Modification Example <NUM>, a fuel cell apparatus provided in each of a plurality of facilities <NUM> outputs electric power based on a storage amount allocated by a power management server <NUM>. For example, the fuel cell apparatus in each facility <NUM> 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 <NUM> controls the output power to be rate power in a case where the storage amount is allocated by the above-described third allocation method.

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 <NUM> is an energy management apparatus that allocates the storage amount of the fuel stored in the storage tank <NUM> is exemplified. However, the embodiment is not limited thereto. For example, the energy management apparatus may correspond to one or more local control apparatuses <NUM> provided in the plurality of facilities <NUM>. The energy management apparatus may be a server or an apparatus provided separately from the power management server <NUM>. 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 <NUM> to be provided in the facility <NUM> may not necessarily be provided in the facility <NUM>. For example, some of the functions of the local control apparatus <NUM> may be provided by a cloud server provided on the Internet. That is, it may be considered that the local control apparatus <NUM> 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 <NUM> may allocate the storage amount more than that for the facility <NUM> including the fuel cell apparatus having relatively high power generation efficiency, to the facility <NUM> 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 <NUM>. For example, a case where a hospital, a corner store, and a bookstore are provided as the plurality of facilities <NUM> 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 <NUM> having a high degree of urgency. Thus, it is possible to allocate the large storage amount of the fuel to the facility <NUM> having a high degree of urgency.

In the embodiment, a case where the first protocol is a protocol based on Open ADR2. <NUM>, 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 <NUM> and the local control apparatus <NUM> may be provided. As the second protocol, a protocol standardized as a protocol used in the facility <NUM> may be provided.

Claim 1:
An energy management method comprising:
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, by an energy management apparatus, a storage amount of the fuel stored in a storage tank shared by the plurality of facilities; and
a step C of allocating, by the energy management apparatus, the storage amount of the fuel to each of the plurality of facilities, characterized in that
the step C includes a step of :
evenly allocating, by the energy management apparatus, the storage amount of the fuel, or
allocating, by the energy management apparatus, the storage amount of the fuel based on any one of:
a history of power consumption of each of the plurality of facilities,
rated output power of the fuel cell apparatus provided in each of the plurality of facilities,
a remaining charge of a storage battery apparatus provided in one or more facilities among the plurality of facilities,
a power generation prediction amount of a solar cell apparatus provided in one or more facilities among the plurality of facilities, and
a timing at which replenishment of the fuel to the storage tank resumes, wherein
the step of allocating includes a step of transmitting a message indicating allocated result to each of the plurality of facilities.