JPH1172028A - Electric power leveling power generation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain high power generation efficiency without generating toxic exhaust gas by producing hydrogen and oxygen due to the electrolysis of water by electric power in the night time to compress them for storage and burning the hydrogen and oxygen in the daytime to generate high temperature and high pressure gas and introduce it into a gas turbine generator so as to generate electric power. SOLUTION: Excess electric power during night time generated by an alternating current generator 1 is converted into a direct current by a rectifier 2 during night to supply it to an electrolysis device 3. The hydrogen and oxygen obtained due to the electrolysis of water in this electrolysis device 3 are compressed by compressors 4, 5 to store in high pressure tanks 8, 9. In the daytime, the high pressure hydrogen, the high pressure oxygen, and water vapor as diluent are preheated by a heat exchanger 10 and burned by a combustor 11 to generate high temperature and high pressure gas. A gas turbine 12 is driven by the high temperature and high pressure gas to generate electric power by a generator 13. Furthermore, exhaust gas which comes out of the gas turbine 12 enters a boiler 14 to generate steam so that the steam is utilized in a steam cycle to obtain high power generation efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power leveling method using nighttime power.

[0002]

2. Description of the Related Art In a power company, it is necessary to prepare facilities in response to temporal fluctuations in power demand. That is, power consumption peaks especially in the summer daytime, and large-scale facilities that can cope with the peak power consumption are required. Therefore, various studies have been made to store the surplus power at night, which consumes less power, and to suppress the enlargement of the power generation equipment by so-called power leveling, which discharges the surplus power during the day.

[0003] As a power storage system that is currently in practical use, there is only pumped-storage power generation, which pumps water with surplus power at night and converts the potential energy of the water into electric energy when power consumption is large in the daytime. However, thermal power leveling has not been established.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to obtain a high power generation efficiency without generating harmful exhaust gas, It is an object of the present invention to provide a power leveling power generation method that requires only a small power consumption.

[0005]

In order to solve the problems of the prior art, according to the present invention, water and water are electrolyzed by night power to produce hydrogen and oxygen, and the hydrogen and oxygen are separated from each other. The gas is compressed and stored, and the hydrogen and oxygen are burned in the daytime to generate a high-temperature and high-pressure gas, and the high-temperature and high-pressure gas is guided to a gas turbine generator to generate power. Further, in the present invention, the high-temperature and high-pressure gas is mixed with steam as a diluent. Furthermore, in the present invention, steam is generated by the gas turbine exhaust, and the steam is guided to a steam turbine generator to generate power.

In the power leveling power generation method according to the present invention, hydrogen and oxygen are obtained by electrolysis of water, so that the efficiency is high. The hydrogen and oxygen are burned to drive a gas turbine, and the steam is used as a diluent. Therefore, the steam is generated by exhausting the gas turbine, and the steam is guided to the steam turbine to drive the generator, so that the power generation efficiency is high.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments.

FIG. 1 is a system diagram for implementing the power leveling method of the present invention. The upper half of the figure shows a part of a system for converting electrical energy into chemical energy at night and storing it. The lower half shows the part of the system that converts the stored chemical energy into electrical energy during the day.

In this system, the nighttime surplus power generated by the AC generator 1 is converted into DC by the rectifier 2 at night and supplied to the electrolyzer 3. The hydrogen and oxygen obtained by the electrolysis in the electrolyzer 3 are compressed by the corresponding compressors 4 and 5, respectively, and then cooled by the coolers 6 and 7.
And stored in the high-pressure tanks 8 and 9 respectively.

In the daytime, high-pressure hydrogen and high-pressure oxygen produced at night and stored in the high-pressure tanks 8 and 9 and steam as a diluent introduced from a steam turbine described later are described later in the heat exchanger 10. Preheat by gas turbine exhaust gas. Then, these fluids are burned in the combustor 11,
After mixing, a predetermined high-temperature and high-pressure gas (for example,
Pa) is generated, and the gas turbine 12 is driven by the high-pressure gas. As a result, power is generated by the generator 13. The exhaust gas leaving the gas turbine 12 preheats each fluid in the heat exchanger 10 as described above, and then enters the boiler 14 to generate steam. Then, a part of the exhaust gas enters the condenser 15 and is used as a working fluid of the steam cycle, and the other exhaust gas is discharged to the outside.

Next, the steam cycle will be described.
The water is pressurized by a pump 16, turned into steam in a boiler 14, and sent to a steam turbine 17 under pressure.
7 is driven. As a result, power is generated by the generator 18. A part of the expanded steam discharged from the steam turbine 17 is preheated through the heat exchange 10 as a diluent and supplied to the combustor 11 of the gas turbine 12, and the other steam is condensed by the condenser 15. You.

Although the embodiments of the present invention have been described above, the power leveling power generation method of the present invention is not limited to the above-described embodiments, and various methods based on the technical idea of the present invention are provided. Modifications and changes are possible, and various changes can be made without departing from the spirit of the present invention. For example, in the above embodiment, hydrogen is supplied to the high pressure tank 8.
However, it is also possible to store energy in the form of hydrogen using a hydrogen storage alloy or the like which can safely and simply store energy for a long period of time.

[0013]

As described above, the power leveling method according to the present invention produces hydrogen and oxygen by electrolyzing water with nighttime power, compresses and stores the hydrogen and oxygen, respectively, Burning the hydrogen and oxygen in the daytime to generate a high-temperature high-pressure gas, guiding the high-temperature high-pressure gas to a gas turbine generator to generate power, further using steam as a diluent, and generating steam by gas turbine exhaust, The steam is guided to a steam turbine generator to generate power. Therefore, according to the power leveling power generation method of the present invention, the following effects can be obtained. (1) By utilizing surplus power at night, water can be decomposed into hydrogen and oxygen, and electric energy can be stored as chemical energy. (2) Hydrogen and oxygen can be stored as mechanical pressure energy by increasing the pressure. (3) Hydrogen as a fuel and oxygen as an oxidant are produced by electric energy, and these are stored under high-pressure conditions or with a hydrogen storage alloy, so that a huge tank is not required unlike compressed air storage. . (4) Steam is used as a diluent for combustion gas.
It can be generated and supplied in a boiler without storage. Therefore, electric energy is efficiently stored as chemical energy and mechanical energy, and the storage tank or the like may be small, so that the equipment is small and can be installed in a necessary area or place. The efficiency of the system depends on the efficiency of electrolysis, but the efficiency of the power generation system is as high as 60% or more. In addition, since no harmful exhaust gas is generated, there is no possibility that the exhaust gas is clean and adversely affects the environment. Further, since the gas turbine and the steam turbine are combined, it is easy to cope with load fluctuation, and the efficiency does not decrease so much even in partial load operation.

[Brief description of the drawings]

FIG. 1 is a system diagram of a power generation system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alternator 2 Rectifier 3 Electrolyzer 4,5 Compressor 6,7 Cooler 8,9 High-pressure tank 10 Heat exchanger 11 Combustor 12 Gas turbine 13 Generator 14 Boiler 15 Condenser 16 Pump 17 Steam turbine 18 Power generation Machine

Continuation of front page (72) Inventor Tadashi Tsuji 2-1-1, Shinhama, Arai-machi, Takasago-shi, Hyogo Prefecture Inside the Mitsubishi Heavy Industries, Ltd. Takasago Machinery Works

Claims (3)

[Claims] 1. A method for producing hydrogen and oxygen by electrolyzing water with nighttime electric power, compressing and storing the hydrogen and oxygen, respectively, and burning the hydrogen and oxygen during the day to generate a high-temperature high-pressure gas. A power leveling method, wherein the high-temperature high-pressure gas is guided to a gas turbine generator to generate power. 2. The power leveling method according to claim 1, wherein steam is mixed with the high-temperature and high-pressure gas as a diluent. 3. The power leveling method according to claim 1, wherein steam is generated by the gas turbine exhaust, and the steam is guided to a steam turbine generator to generate power.