AU2022324920A1 - Power-conditioning system, power-conditioning method, and power-conditioning program - Google Patents

Abstract

A power-conditioning system 1 is provided with: a surplus power supply unit 11 for supplying surplus power that exceeds the power acceptable by a power supply system 3, of power generated by renewable energy power generation equipment 2, to water electrolysis equipment 4, and producing hydrogen and oxygen by electrolysis of water; a storage unit 15 for storing, by liquefying and pressurizing, the hydrogen and the oxygen produced by the water electrolysis equipment 4; a power generation unit 16 for generating power by combusting the hydrogen and the oxygen stored by the storage unit 15; and, a condensing unit 13 for condensing, by cold heat from the hydrogen and the oxygen stored in the storage unit 15, water vapor generated during combustion of the hydrogen and the oxygen in the power generation unit 16, for circulation to the water electrolysis equipment 4.

Description

DESCRIPTION

Title of Invention

POWER-CONDITIONING SYSTEM, POWER-CONDITIONING METHOD, AND POWER-CONDITIONING PROGRAM

Technical Field

[0001]

The present invention relates to a power-conditioning

technique.

Background Art

[0002]

PTL 1 discloses a system that supplies power, which is

generated by biomass power generation equipment that

combusts biomass fuel, to a water electrolysis equipment

and that produces hydrogen through electrolysis of water.

In addition to biomass, it is also possible to use power,

which is generated based on renewable energy with large

fluctuation such as solar power, wind power, hydraulic

power, and geothermal power, for electrolysis of water

(paragraph 0023).

Citation List

Patent Literature

[0003]

[PTL 11 Japanese Unexamined Patent Publication No.

2005-213631

Summary of Invention

Technical Problem

[0004]

Although there is an expectation that hydrogen is

considered to be a clean energy source that does not

generate greenhouse effect gases such as carbon dioxide

during combustion, the market is still immature, so it is

extremely difficult to estimate the appropriate size of

equipment, and business operators of the water electrolysis

equipment are hesitant to invest in equipment.

[00051

The present invention has been made in view of these

circumstances, and the purpose of the present invention is

to provide a power-conditioning system that can reduce the

hurdles for investing in water electrolysis equipment.

Solution to Problem

[00061

In order to solve the above problems, a power

conditioning system according to an aspect of the present

invention includes: a power supply unit that supplies power to water electrolysis equipment and that causes the water electrolysis equipment to produce hydrogen and oxygen through electrolysis of water; a storage unit that stores the hydrogen and the oxygen, which are produced by the water electrolysis equipment; and a power generation unit that generates power by combusting the hydrogen and the oxygen, which are stored in the storage unit.

[0007]

According to this aspect, the hydrogen and the oxygen,

which are produced through electrolysis of water, can be

stored, and a necessary amount thereof that meets the power

demand can be combusted to generate power. Since it is easy

to predict power demand compared to hydrogen demand in the

immature hydrogen market, business operators of water

electrolysis equipment can estimate the appropriate

equipment size. Further, the generation of greenhouse

effect gas can be suppressed by combusting hydrogen, which

is a clean energy source, in the power generation unit.

[0008]

Another aspect of the present invention is a power

conditioning method. The power-conditioning method

includes: a power supply step of supplying power to water

electrolysis equipment and causing the water electrolysis

equipment to produce hydrogen and oxygen through

electrolysis of water; a storage step of storing the hydrogen and the oxygen, which are produced by the water electrolysis equipment; and a power generation step of generating power by combusting the hydrogen and the oxygen, which are stored in the storage step.

[00091

Further, any combination of the above-described

components and a conversion of the expression of the

present invention between methods, devices, systems,

recording media, computer programs, and the like are also

effective as aspects of the present invention.

Advantageous Effects of Invention

[0010]

According to the present invention, it is possible to

provide a power-conditioning system that can reduce hurdles

for investing in water electrolysis equipment.

Brief Description of Drawings

[0011]

Fig. 1 is a functional block diagram illustrating a

power-conditioning system.

Fig. 2 is a schematic diagram illustrating a detailed

configuration of gas storage power generation equipment.

Description of Embodiments

[0012]

Hereinafter, an embodiment for performing the present

invention will be described in detail with reference to the

drawings. In the description and drawings, the same or

equivalent components, members, and processing will be

assigned with the same reference symbols, and redundant

descriptions thereof will be omitted as appropriate. The

scales or shapes of illustrated constituents are set for

convenience in order to make the description easy to be

understood, and are not to be understood as limiting unless

stated otherwise. The embodiment is an example and does not

limit the scope of the present invention in any way.

Individual features or combinations thereof described in

the embodiment are not necessarily essential to the

invention.

[0013]

Fig. 1 is a functional block diagram illustrating a

power-conditioning system 1 according to the present

embodiment. The power-conditioning system 1 includes

renewable energy power generation equipment 2, a power

supply system 3, water electrolysis equipment 4, and gas

storage power generation equipment 5.

[0014]

The renewable energy power generation equipment 2

generates power based on renewable energy such as solar power, wind power, hydraulic power, geothermal power, and biomass. The renewable energy is energy that is constantly or repeatedly supplied from the natural world and is expected as clean energy alternative to fossil fuels, which produce greenhouse effect gases or air pollutants by combustion. On the other hand, the renewable energy fluctuates largely depending on natural conditions such as topography and weather and is often unstable and difficult to predict. Further, in many countries and regions including Japan, in order to balance the supply and demand of power, there may be restrictions on connecting power generated based on renewable energy to the power supply system 3 that is responsible for power transformation, power transmission, and power distribution operated by a power company (referred to as "output suppression" or

"output control" in Japan). In this case, the amount of

power, which exceeds power that is acceptable by the power

supply system 3 out of the power generated by the renewable

energy power generation equipment 2, becomes surplus power.

[00151

The surplus power, which is generated by the renewable

energy power generation equipment 2 and is unable to be

connected to the power supply system 3, is used by the

water electrolysis equipment 4 as surplus power use

equipment. Specifically, a surplus power supply unit 11, which is serving as a power supply unit, supplies the surplus power generated by the renewable energy power generation equipment 2 to the water electrolysis equipment

4 and causes the water electrolysis equipment 4 to produce

hydrogen and oxygen through electrolysis of water. The

surplus power, which is supplied to the water electrolysis

equipment 4 by the surplus power supply unit 11, is

expected to fluctuate largely because it is affected by the

unstable power generation amount in the renewable energy

power generation equipment 2 and sudden output suppression

in the power supply system 3.

[0016]

In a case where the fluctuations in the surplus power

used for electrolysis of water are large in this way, when

the producing capability or capacity of the hydrogen/oxygen

in the water electrolysis equipment 4 is adjusted to the

maximum amount of surplus power expected, an operation

ratio of the water electrolysis equipment 4 becomes low in

time slots where the amount of surplus power to be supplied

is small, resulting in inefficiency. Further, the

installation and maintenance of the water electrolysis

equipment 4 having such an excessive capability or capacity

requires a great deal of expense. As a result, the water

electrolysis equipment 4 becomes less economical, and the

hydrogen and the oxygen, which are produced in the water electrolysis equipment 4, also become expensive. In particular, there is a strong need to reduce the production cost of hydrogen in order to realize a decarbonized society or a hydrogen society, and it is unlikely that such high cost hydrogen will become widespread in society. On the other hand, when the producing capability or capacity of the hydrogen/oxygen in the water electrolysis equipment 4 is adjusted to the minimum amount of surplus power expected, power that is not used for electrolysis of water is wasted in time slots where the amount of surplus power to be supplied is large.

[0017]

As described above, the imbalance among the unstable

power generation amount at the renewable energy power

generation equipment 2, the power amount acceptable at the

power supply system 3 that fluctuates depending on the

power demand, and the power amount used in water

electrolysis equipment 4 are the cause of the low economic

efficiency of the water electrolysis equipment 4 and the

high production cost of hydrogen. In order to correct the

imbalance, in the present embodiment, gas storage power

generation equipment 5 is provided, and surplus power

generated by the renewable energy power generation

equipment 2 is efficiently utilized. Specifically, the gas

storage power generation equipment 5 liquefies and/or pressurizes the hydrogen and the oxygen, which are produced by the water electrolysis equipment 4 by using the surplus power, and then stores the hydrogen and the oxygen when the surplus power is generated in the renewable energy power generation equipment 2, such as when the power supply system 3 performs output suppression. On the other hand, when the renewable energy power generation equipment 2 alone cannot cover the power demand, such as when the power demand of the power supply system 3, which does not perform output suppression, is increased, the gas storage power generation equipment 5 generates insufficient power by combusting the stored hydrogen and oxygen.

[0018]

When there is a demand for hydrogen and/or oxygen

itself stored in the gas storage power generation equipment

5, the hydrogen and/or oxygen may be directly supplied or

sold to consumers instead of being used to generate power

for insufficient power in the power supply system 3. In

this way, the business operator operating the gas storage

power generation equipment 5 can flexibly determine a

supply mode (power or industrial gas) of the hydrogen and

the oxygen, which are stored in the gas storage power

generation equipment 5 in line with the power demand of the

power supply system 3 and the demand for hydrogen/oxygen as

industrial gas. For example, it is possible to focus on generating and selling power through the combustion of hydrogen and oxygen while the growing hydrogen market is still immature, and it is also possible to diversify into supplying and selling hydrogen as an industrial gas to maximize business opportunities and business profits as the hydrogen market matures. Providing the highly flexible and economically efficient gas storage power generation equipment 5 in this way leads to a reduction in the production cost of hydrogen, thereby contributing to the early realization of a decarbonized society or a hydrogen society. In the following description, it is assumed that all the hydrogen and oxygen stored in the gas storage power generation equipment 5 are used for power generation of insufficient power of the power supply system 3.

[0019]

The power-conditioning system 1, which adjusts power

among the renewable energy power generation equipment 2,

the power supply system 3, and the water electrolysis

equipment 4, includes a surplus power supply unit 11, a

storage power generation control unit 12, a storage unit

15, a power generation unit 16, a gas storage unit 17, a

hot heat storage unit 18, a cold heat storage unit 19, a

condensing unit 13, and an atmosphere take-in unit 14.

Among these functional blocks, the storage unit 15, the

power generation unit 16, the gas storage unit 17, the hot heat storage unit 18, the cold heat storage unit 19, the condensing unit 13, and the atmosphere take-in unit 14 are components of the gas storage power generation equipment 5.

[0020]

Further, the surplus power supply unit 11 and the

storage power generation control unit 12 are realized by

cooperation of a central calculation processing device of a

computer, a memory, an input device, an output device,

hardware resources such as peripheral devices connected to

the computer, and software executed using these resources.

Regardless of the type or the installation location of the

computer, each of the above functional blocks may be

realized with the hardware resources of a single computer

or may also be realized by combining hardware resources

distributed across a plurality of computers. In particular,

in the present embodiment, part or all of the surplus power

supply unit 11 and the storage power generation control

unit 12 may be realized by a computer provided in the water

electrolysis equipment 4 or the gas storage power

generation equipment 5, or may be realized by an external

computer that is communicable with each piece of equipment.

[0021]

The surplus power supply unit 11 supplies the water

electrolysis equipment 4 with surplus power that exceeds

the power acceptable by the power supply system 3 out of the power generated by the renewable energy power generation equipment 2. Here, in a case where the power generated by the renewable energy power generation equipment 2 is denoted by Pa, the power accepted by the power supply system 3 is denoted by Pb ( Pa), and the surplus power is denoted by Pc, it is expressed as Pc = Pa

- Pb. In the case of a power shortage where the power

generation amount Pa is smaller than the demand amount Pb,

that is, in a case where the renewable energy power

generation equipment 2 alone cannot cover the power demand

of the power supply system 3, no surplus power is supplied

from the surplus power supply unit 11 to the water

electrolysis equipment 4 (Pc = 0). At this time, as will be

described later, the power generation unit 16 generates the

insufficient power Pd (= Pb - Pa) and supplies the

insufficient power Pd to the power supply system 3.

[0022]

The storage power generation control unit 12 compares

the power generation amount Pa of the renewable energy

power generation equipment 2 and the demand amount Pb of

the power supply system 3 and causes the gas storage power

generation equipment 5 to perform liquefaction/pressurized

storage or combustion power generation of hydrogen and

oxygen depending on the size of the comparison result.

Specifically, hydrogen and oxygen in an amount corresponding to the surplus power Pc are stored, by liquefying and/or pressurizing the hydrogen and the oxygen, in the storage unit 15 during a power surplus when the power generation amount Pa exceeds the demand amount Pb, and the power generation unit 16 generates power of the insufficient power Pd by combusting the hydrogen and oxygen during a power shortage when the demand amount Pb exceeds the power generation amount Pa.

[0023]

As illustrated in Fig. 1, Pa - Pc = Pb, which is

obtained by subtracting the surplus power Pc (= Pa - Pb)

from the power generation amount Pa of the renewable energy

power generation equipment 2, is supplied to the power

supply system 3 during a power surplus, and Pa + Pd = Pb,

which is obtained by adding the power generation amount Pa

of the renewable energy power generation equipment 2 to the

insufficient power Pd (= Pb - Pa) generated by the power

generation unit 16, is supplied to the power supply system

3 during a power shortage. In this way, as long as hydrogen

and oxygen are stored in the gas storage power generation

equipment 5 for the power generation unit 16 to generate

the insufficient power Pd, the power supply system 3 is

always supplied with the demanded power Pb. As described

above, although both the power generation amount Pa of the

renewable energy power generation equipment 2 and the demand amount Pb of the power supply system 3 can fluctuate largely, in the present embodiment, since the gas storage power generation equipment 5 absorbs respective fluctuations or imbalances, the power required by the power supply system 3 can be stably supplied. Further, since the surplus power Pc during a power surplus is stored in a form of hydrogen and oxygen by the storage unit 15, and the insufficient power Pd during a power shortage is generated by the power generation unit 16 that combusts the stored hydrogen and oxygen, the power can be efficiently supplied, without causing large power loss in the power-conditioning system 1, to the power supply system 3 without excess or deficiency.

[0024]

The hot heat, which is collected when the storage unit

stores the hydrogen and oxygen, is stored in the hot

heat storage unit 18 and is used when the power generation

unit 16 combusts the hydrogen and oxygen. Further, the cold

heat, which is collected when the power generation unit 16

combusts the hydrogen and oxygen, is stored in the cold

heat storage unit 19 and is used when the storage unit 15

stores the hydrogen and oxygen. In this way, by utilizing

the heat generated in one treatment of storage and

combustion in the other treatment, it is possible to increase the efficiency of the entire gas storage power generation equipment 5.

[0025]

The condensing unit 13 condenses water vapor, which is

generated during combustion of the hydrogen and oxygen in

the power generation unit 16, by using cold heat from the

hydrogen and the oxygen, which are stored in the storage

unit 15, and circulates the water vapor back to the water

electrolysis equipment 4. Although the specific

configuration will be described later, the high-temperature

water vapor, which is generated in the power generation

unit 16, is cooled by thermally contacting the low

temperature hydrogen and oxygen stored in the gas storage

unit 17 via the storage unit 15 and returns to water

through the condensation or congelation. The condensing

unit 13 also condenses water vapor contained in the

atmosphere taken in by the atmosphere take-in unit 14

through a dew condensation phenomenon or the like.

[0026]

In this way, since the water, which is automatically

or naturally condensed in the gas storage power generation

equipment 5, circulates back to the water electrolysis

equipment 4, the amount of water supplied to the water

electrolysis equipment 4 can be significantly reduced. In

particular, when a sufficient amount of water for the operation of the water electrolysis equipment 4 is constantly supplied from the atmosphere taken in by the atmosphere take-in unit 14, it is also possible to reduce the amount of water supplied to the water electrolysis equipment 4 to zero. Therefore, the power-conditioning system 1 of the present embodiment can be easily introduced into desert areas or the like where water resources are insufficient. Furthermore, since the desert areas often have abundant sunlight, when the renewable energy power generation equipment 2 of the present embodiment is solar power generation equipment, it is possible to construct an efficient power-conditioning system 1 that minimizes the use of scarce water resources while maximizing the use of abundant solar resources.

[0027]

Fig. 2 is a schematic diagram illustrating a detailed

configuration of the gas storage power generation equipment

5. As also illustrated in Fig. 1, the gas storage power

generation equipment 5 includes the storage unit 15, the

power generation unit 16, the gas storage unit 17, the hot

heat storage unit 18, the cold heat storage unit 19, the

condensing unit 13, and the atmosphere take-in unit 14. The

storage unit 15 includes a gas pressurizing unit 51 and a

gas liquefying unit 52. In the following description, the hydrogen and oxygen produced in the water electrolysis equipment 4 may be collectively referred to as gas.

[0028]

The gas pressurizing unit 51 includes a motor 511 that

generates rotational power based on the surplus power Pc

from the renewable energy power generation equipment 2, a

compressor 512 that is rotationally driven by the motor 511

to pressurize or compress the hydrogen and oxygen produced

in the water electrolysis equipment 4, a final cooler 513

that cools the gas pressurized by the compressor 512 by

using external cold heat or the like to condense and

separate moisture, and a dryer 514. Although not

illustrated, the moisture, which is condensed and separated

in the final cooler 513, may be directly circulated back to

the water electrolysis equipment 4 or may be indirectly

circulated back to the water electrolysis equipment 4 via

the condensing unit 13.

[0029]

The compressor 512 includes a rotary shaft 512A that

is rotationally driven by the motor 511, and a first

compression part 512B and a second compression part 512C

that are attached to the rotary shaft 512A. The hydrogen

and oxygen introduced into the gas pressurizing unit 51

from the water electrolysis equipment 4 are pressurized by

the first compression part 512B and sent to the first cooling unit 513A in the final cooler 513. The gas from which the moisture has been removed through the condensation separation in the first cooling unit 513A is sent to the dryer 514 and is further dried. Further, the first cooling unit 513A, which is a heat exchanger, separates the hot heat contained in the high-temperature compressed gas from the first compression part 512B and sends the hot heat to the hot heat storage unit 18. The gas, which is dried by the dryer 514, is further pressurized by the second compression part 512C and is sent to the second cooling unit 513B in the final cooler 513.

The gas from which the moisture has been removed by

condensation separation in the second cooling unit 513B is

sent to the gas liquefying unit 52. Further, the second

cooling unit 513B, which is a heat exchanger, separates the

hot heat contained in the high-temperature compressed gas

from the second compression part 512C and the hot heat

contained in the exhaust from the hot heat storage unit 18

and sends the hot heat to the first cooling unit 513A. The

first cooling unit 513A separates the hot heat contained in

the compressed gas from the first compression part 512B and

the hot heat from the second cooling unit 513B and sends

the hot heat to the hot heat storage unit 18.

[00301

The gas liquefying unit 52 includes a main heat

exchanger 521, a liquefier 522, and a cold insulation

container 523 for accommodating the main heat exchanger 521

and the liquefier 522. The main heat exchanger 521 includes

a liquefaction path 521A, a vapor circulation path 521B,

and a cold heat supply path 521C that are separated from

each other. Dry gas from the second cooling unit 513B in

the gas pressurizing unit 51 flows into the liquefaction

path 521A, and the dry gas is cooled by the cold heat

passing through the cold heat supply path 521C and low

temperature vapor passing through the vapor circulation

path 521B.

[0031]

The liquefaction path 521A is branched, and an

isentropic expander 522A as a liquefier 522 and a Joule

Thomson valve 522B are provided at each of branch

destinations. The isentropic expander 522A performs

isentropic expansion on the low-temperature dry gas from

the liquefaction path 521A and further reduces the

temperature to liquefy the dry gas. The Joule-Thomson valve

522B expands the low-temperature dry gas from the

liquefaction path 521A through a throttle mechanism such as

a porous material and further reduces the temperature by

using the Joule-Thomson effect to liquefy the dry gas. The

hydrogen and oxygen liquefied through the isentropic expander 522A and/or the Joule-Thomson valve 522B are sent to and stored in the gas storage unit 17.

[0032]

The low-temperature dry vapor, which is sent together

with the gas liquefied by the isentropic expander 522A

and/or the Joule-Thomson valve 522B, flows into the vapor

circulation path 521B, and the dry vapor joins the dry gas

flowing between the output of the dryer 514 and the input

of the second compression part 512C after being used to

cool the dry gas passing through the liquefaction path

521A. The cold heat, which passes through the cold heat

supply path 521C, is supplied from the cold heat storage

unit 19 and circulates back to the cold heat storage unit

19 after being used to cool the dry gas passing through the

liquefaction path 521A.

[0033]

A necessary amount of the cryogenic temperature

liquefied gas, which is stored in the gas storage unit 17,

is taken out from the gas storage unit 17 by a cryogenic

temperature pump 171 when combustion power generation

treatment is performed by the power generation unit 16. The

gas storage unit 17, which stores each of the

pressurized/liquefied hydrogen and oxygen, is individually

provided, the pressurized/liquefied hydrogen and oxygen are

stored in modes or conditions suitable for each, and each required amount may be taken out from each gas storage unit

17 through the individual cryogenic temperature pump 171

when the combustion power generation treatment is

performed. The cryogenic temperature liquefied gas from the

cryogenic temperature pump 171 flows into the heat

exchanger 191 which is provided incidentally to the cold

heat storage unit 19 and constitutes a part of the power

generation unit 16. The heat exchanger 191 separates the

cold heat contained in the liquefied gas from the cryogenic

temperature pump 171 from the cold heat contained in the

exhaust from the cold heat storage unit 19 and supplies the

cold heat to the cold heat storage unit 19. In this way,

the cryogenic temperature liquefied gas, which is stored in

the gas storage unit 17, is supplied as the cold heat to be

supplied to the cold heat supply path 521C of the main heat

exchanger 521. Further, when the cold heat are separated by

the heat exchanger 191, a part or all of the cryogenic

temperature liquefied gas, which is supplied from the

cryogenic temperature pump 171, may be vaporized. Further,

the cold heat, which is taken out from the stored

pressurized/liquefied hydrogen and oxygen in the heat

exchanger 191, is also used in condensing treatment in the

condensing unit 13.

[00341

The power generation unit 16, which is supplied with

the liquefied gas stored in the gas storage unit 17 via the

heat exchanger 191, includes a reheat exchanger 161 that

heats the hydrogen and oxygen, which have passed through

the heat exchanger 191, to vaporize or expand the hydrogen

and the oxygen, a combustion unit 162 that combusts the

hydrogen and oxygen heated in the reheat exchanger 161, and

a power generator 163 that generates power based on

combustion in the combustion unit 162. The gas from the

heat exchanger 191 is heated by using the hot heat, which

is stored in the hot heat storage unit 18, or external hot

heat in the reheat exchanger 161 and is sent to the

combustion unit 162. Here, the hot heat as the exhaust heat

of the reheat exchanger 161 is circulated back to the hot

heat storage unit 18. Further, the cold heat, which is

taken out from the hydrogen and oxygen in the reheat

exchanger 161, is used for the condensing treatment in the

condensing unit 13.

[00351

The combustion unit 162 is configured as, for example,

a boiler, generates vapor from water with heat generated by

combustion of hydrogen and oxygen, and rotates a vapor

turbine provided in the power generator 163. As a result,

in the power generator 163, the insufficient power Pd (= Pb

- Pa) during a power shortage when the demand amount Pb of the power supply system 3 exceeds the power generation amount Pa of the renewable energy power generation equipment 2, is generated. Further, the generation of greenhouse effect gas can be suppressed by combusting hydrogen, which is a clean energy source, in the combustion unit 162. The water, which is condensed by the condensing unit 13, or the moisture, which is condensed and separated by the final cooler 513, may be supplied to the boiler as a vapor generation source.

[00361

The water vapor, which is generated during the

combustion of hydrogen and oxygen in the combustion unit

162, is supplied to the condensing unit 13 and is cooled by

cold heat from the heat exchanger 191 and/or the reheat

exchanger 161 and returns to water. Further, the water

vapor, which is contained in the humid atmosphere taken in

by the atmosphere take-in unit 14, is also cooled by the

cold heat from the heat exchanger 191 and/or the reheat

exchanger 161 in the condensing unit 13 and returns to

water through the dew condensation. The water as a liquid

that is condensed in the condensing unit 13 in this manner

is circulated back to the water electrolysis equipment 4

and is used again for the electrolysis.

[0037]

The present invention has been described above based

on the embodiment. The embodiment is an example, and it is

understood by those skilled in the art that various

modification examples are possible for each of the

components and combinations of each treatment process, and

that such modification examples are also within the scope

of the present invention.

[00381

In an embodiment, although pressurization and

liquefaction are performed by the gas pressurizing unit 51

and the gas liquefying unit 52, either pressurization or

liquefaction may be performed when hydrogen and oxygen are

stored. The pressurized gas can generate cold heat used in

the condensing unit 13 or the like by expanding during the

combustion power generation, and the liquefied gas can

generate cold heat used in the condensing unit 13 or the

like by vaporizing during the combustion power generation.

[00391

Further, the functional configuration of each device

described in the embodiment can be realized by a hardware

resource or a software resource, or by the cooperation of

the hardware resource and the software resource. A

processor, ROM, RAM, or other LSI can be used as the

hardware resource. Programs such as operating systems and

applications can be used as the software resources.

Industrial Applicability

[0040]

The present invention relates to a power-conditioning

technique.

Reference Signs List

[0041]

1 power-conditioning system

2 renewable energy power generation equipment

3 power supply system

4 water electrolysis equipment

5 gas storage power generation equipment

11 surplus power supply unit

12 storage power generation control unit

13 condensing unit

14 atmosphere take-in unit

15 storage unit

16 power generation unit

17 gas storage unit

18 hot heat storage unit

19 cold heat storage unit

51 gas pressurizing unit

52 gas liquefying unit

162 combustion unit

163 power generator

Claims (11)

1. A power-conditioning system comprising:

a power supply unit that supplies power to water

electrolysis equipment and that causes the water

electrolysis equipment to produce hydrogen and oxygen

through electrolysis of water;

a storage unit that stores the hydrogen and the

oxygen, which are produced by the water electrolysis

equipment; and

a power generation unit that generates power by

combusting the hydrogen and the oxygen, which are stored in

the storage unit.

2. The power-conditioning system according to Claim

1, wherein

the storage unit liquefies the hydrogen and the

oxygen, which are produced by the water electrolysis

equipment, and then stores the hydrogen and the oxygen.

3. The power-conditioning system according to Claim 1

or 2, wherein

the storage unit pressurizes the hydrogen and the

oxygen, which are produced by the water electrolysis

equipment, and then stores the hydrogen and the oxygen.

4. The power-conditioning system according to Claim 1

or 2, further comprising:

a condensing unit that condenses water vapor, which is

generated during combustion of the hydrogen and oxygen in

the power generation unit, by using cold heat from the

hydrogen and the oxygen, which are stored in the storage

unit, and that circulates the water vapor back to the water

electrolysis equipment.

5. The power-conditioning system according to Claim

4, further comprising:

an atmosphere take-in unit that takes in atmosphere,

wherein

the condensing unit also condenses water vapor

contained in the taken-in atmosphere.

6. The power-conditioning system according to Claim 1

or 2, wherein

the power supply unit supplies the water electrolysis

equipment with surplus power that exceeds power acceptable

by a power supply system out of power generated by power

generation equipment.

7. The power-conditioning system according to Claim

6, wherein

the power generation equipment is renewable energy

power generation equipment that generates power based on

renewable energy.

8. The power-conditioning system according to Claim 1

or 2, further comprising:

a hot heat storage unit that stores hot heat, which is

collected when the storage unit stores the hydrogen and the

oxygen, and that supplies the hot heat when the power

generation unit combusts the hydrogen and the oxygen.

9. The power-conditioning system according to Claim 1

or 2, further comprising:

a cold heat storage unit that stores cold heat, which

is collected when the power generation unit combusts the

hydrogen and the oxygen, and that supplies the cold heat

when the storage unit stores the hydrogen and the oxygen.

10. A power-conditioning method comprising:

a power supply step of supplying power to water

electrolysis equipment and causing the water electrolysis

equipment to produce hydrogen and oxygen through

electrolysis of water; a storage step of storing the hydrogen and the oxygen, which are produced by the water electrolysis equipment; and a power generation step of generating power by combusting the hydrogen and the oxygen, which are stored in the storage step.

11. A power-conditioning program that causes a

computer to execute:

a power supply step of supplying power to water

electrolysis equipment and causing the water electrolysis

equipment to produce hydrogen and oxygen through

electrolysis of water;

a storage step of storing the hydrogen and the oxygen,

which are produced by the water electrolysis equipment; and

a power generation step of generating power by

combusting the hydrogen and the oxygen, which are stored in

the storage step.