JP2000333481A - Subminiature clean power generating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive subminiature clean power generating system, capable of being easily installed in respective homes, without giving adverse effects the environment. SOLUTION: This system is provided with a wind power generating apparatus 10 generating AC power by means of wind power, a rectifying apparatus 20 converting AC power from the wind power generating apparatus 10 into a DC power, an electrolyzer 30 for electrolyzing water by means of DC power from the rectifying apparatus 20, a photocatalyst/water decomposing apparatus 50 for electrolyzing water by means of sunlight and photocatalyst, a hydrogen storage part 40 storing hydrogen gas generated from the electrolyzer 30 and the photocatalyst/water decomposing apparatus 50 respectively, and a fuel battery 60 for converting hydrogen gas stored in the hydrogen storage part 40 into DC power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean power generation system for supplying electricity to households by generating electricity cleanly by using inexhaustible energy in the natural world such as sunlight and wind power, and more particularly, to an ultra-compact and easy-to-use household. It relates to a clean power generation system that can be used for:

[0002]

2. Description of the Related Art Conventionally, electric power for homes, factories, offices, etc. has been mainly hydroelectric power generation by dams or thermal power generation by coal or oil, and in recent years, nuclear power generation has also been used. . Despite the fact that power is very important in each household, the fact that power generation equipment is large and requires fuel etc. There was almost no use to generate electricity.

[0003]

However, hydroelectric power generation has the drawback that the construction of a dam requires enormous cost and time, and the amount of water storage is affected by the weather. In recent years, opposition to dam construction has become stronger in terms of environmental protection, and the inflow of debris into dam lakes has become a major problem. In addition, thermal power generation relies on the burning of oil and coal, so there is a concern that resources will eventually be depleted from the earth, and there is also a problem in terms of air pollution and global warming. In addition, nuclear power generation, along with safety aspects, poses a serious environmental problem to nearby areas, and there is a strong tendency to stop construction worldwide. For this reason, there is a political problem that nuclear power cannot be relied on in the future.

[0004] Energy demand continues to increase, and it is possible that nuclear and thermal power installations will not be able to keep up with demand in the near future. As described above, conventionally, large-capacity electric power is generated at each power station based on thermal power, hydroelectric power, or nuclear power, and the electric power is transmitted to homes and factories. If the power used in each home can be generated small and clean in each home, there is no need to install many power plants, and the energy problem will be solved at once.

[0005] The present invention has been made in view of the circumstances described above, and an object of the present invention is to change to a lifestyle mainly based on energy consumption that does not affect the environment. Another object of the present invention is to provide an inexpensive, ultra-compact, clean power generation system that can be easily installed in each home.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an ultra-small clean power generation system, and an object of the present invention is to provide a wind power generator for generating AC power by wind power, and to convert AC power from the wind power generator into DC power. A rectifier for conversion, an electrolyzer for electrolyzing water by DC power from the rectifier, a photocatalyst / water splitter for electrolyzing water by sunlight and a photocatalyst, the electrolyzer and the photocatalyst / water This is achieved by providing a hydrogen storage unit that stores hydrogen gas generated from each of the crackers, and a fuel cell that converts the hydrogen gas stored in the hydrogen storage unit into DC power.

Another object of the present invention is to generate AC power by wind power, convert the AC power into DC power,
By supplying hydrogen gas obtained by electrolyzing water with the DC power to a fuel cell to obtain DC power,
Alternatively, it is achieved by supplying hydrogen gas obtained by electrolyzing water with sunlight to a fuel cell to obtain DC power.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, an energy source is obtained from wind and sunlight in the natural world, and is used as a power source and a heat source for home use. Electric power is obtained by wind power, and this electric power is used for water decomposition to generate hydrogen gas, while hydrogen is generated by directly decomposing water with sunlight using a photocatalyst. The hydrogen gas thus obtained is stored in a hydrogen storage unit made of a hydrogen storage metal (hydrogen storage alloy), and the hydrogen gas is supplied to the fuel cell as needed to obtain DC power, or the hydrogen gas is directly burned. To obtain heat energy, to respond to daily or emergency power and heat use in each home, and to promote the use of clean energy.

FIG. 1 is a block diagram showing the concept of the present invention. A wind power generator 10 using a windmill is driven by wind in the natural world, and generates AC power by a generator driven to rotate. The AC power is sent to the rectifier 20 and converted into DC power, and the DC power is supplied to the electrolyzer 30. The electrolyzer 30 electrolyzes water by the supplied DC power, decomposes the water into hydrogen (gas) and oxygen (gas), and converts the obtained hydrogen gas into a hydrogen storage metal (hydrogen storage alloy). The oxygen is released into the air while being sent to the section 40. Wind is obtained day and night, and a large amount of hydrogen gas generated by the wind is stored in the hydrogen storage unit 40. On the other hand, the photocatalyst / water splitter 50 electrolyzes water with sunlight and a photocatalyst to obtain hydrogen (gas) and oxygen (gas), and sends the obtained hydrogen gas to the hydrogen storage unit 40 for storage. Oxygen generated simultaneously in the electrolysis is released into the air. Since sunlight can only be obtained during the day, the photocatalyst /
The hydrogen gas from the water splitter 50 is supplied to the hydrogen storage unit 4 only during the daytime.
Stored at 0. The gas obtained simultaneously with the hydrogen gas in the electrolysis device 30 and the photocatalyst / water decomposition device 50 is harmless oxygen, and only oxygen gas is released into the air, so there is no concern about air pollution.

[0010] The hydrogen gas stored in the hydrogen storage unit 40 is sent to the fuel cell 60 when needed, and the DC power is obtained by the fuel cell 60 and the thermal energy is obtained by directly burning or catalytically burning the hydrogen gas. it can. The wind power generator 10, the rectifier 20, the electrolyzer 30, the hydrogen storage unit 40, the photocatalyst / water splitter 50, and the fuel cell 60 are integrally controlled by a control device (for example, a personal computer) 70. The display device 80 is connected so that the operation status of each device can be monitored.

FIG. 2 is a flowchart showing the relationship between detection and control in each section of FIG. 1. The wind power generator 10 detects the wind speed and direction, and for example, the yaw control, pitch control, and ON / OFF control are performed by the control device. The rectifier 20 detects the voltage and the current. Further, the water amount, the temperature, and the hydrogen gas flow rate are detected by the electrolyzer 30, the water amount control, the temperature control, and the gas flow rate control are executed by the control device 70, and the hydrogen gas pressure and the temperature are detected by the hydrogen storage unit 40, The control is executed, the hydrogen gas flow rate is detected in the hydrogen gas supply to the fuel cell 60, and the gas flow rate control is executed by the control device 70. Further, the temperature is detected in the fuel cell 60 to control the temperature and the amount of electric power. The photocatalyst / water splitter 50 detects the amount of water and the temperature, and the controller 70 executes the amount of water control and the temperature control.

The wind power generator 10 is a power generator in which a generator is mounted on a wind turbine directly or via a gear mechanism or the like. As the wind turbine, a horizontal axis wind turbine as shown in FIG. 3 and a wind turbine as shown in FIG. And the present invention can be applied to any of them. FIG. 3 (A) shows a cell wing type (Greece) windmill, FIG. 3 (B) shows a Dutch windmill, and FIG. 3 (C) shows a propeller type windmill. In this example, an example of three blades is shown. I have. As a horizontal axis windmill, there is a multi-blade windmill. 4A shows a Savonius wind turbine, FIG. 4B shows a cross flow wind turbine, and FIG. 4C shows a Darrieus wind turbine. In addition, there are a paddle wind turbine, a straight Darius, a helix turbine, and the like. To reduce the size of the wind power generator 10, a Savonius wind turbine or a Darius wind turbine is suitable.

The electrolyzer 30 is for decomposing water by DC power. In this embodiment, an electrolysis process using a solid polymer electrolyte is used. The reaction in this case is as follows when an alkali is used.

Anode reaction 2OH ⁻ → 1 / 2O ₂ + H ₂ O + 2e Cathode reaction 2H ₂ O + 2e → H ₂ + 2OH ^— Total reaction H ₂ O → H ₂ + 1 / 2O ₂ Conventional alkaline water electrolysis Although the energy conversion efficiency is limited, the electrolysis method using a solid polymer electrolyte is a method that uses a solid polymer electrolyte instead of the electrolyte solution used for conventional water electrolysis. It is a process that allows electrolysis. FIG. 5 shows a solid polymer electrolyte (SP
E; Solid Polymer Electrolyt
e) shows the principle of the electrolysis process using e), in which a perfluorosulfonic acid-based ion exchange membrane is used for the electrolyte, and electrode catalyst fine particles suitable for the anodic reaction and the cathodic reaction are used for the electrode using a binder such as PTFE. Therefore, it is composed of a film directly bonded to both sides of the film. Since the cathode and anode chambers are separated by a gas-impermeable ion exchange membrane, they can withstand a differential pressure, are easily operated at high pressure, and are easily maintained because the circulating fluid is only water.

The hydrogen storage section 40 is made of a hydrogen storage metal (hydrogen storage alloy), and the crystal structure of the hydrogen storage metal is shown in FIG. FIG. 6A shows a face-centered cubic lattice (fcc) of a structure in which the unit lattice is a cube, and metal atoms are arranged at the vertices and the center of each plane, and FIG. 6B shows the unit lattice. Shows a body-centered cubic lattice (bcc) having a structure in which metal atoms are arranged at each vertex and the center of the cube, and FIG. The hexagonal closest packing (hcp) of the crystal structure formed by repeating the structure with atoms is shown. For example, metals belonging to the face-centered cubic lattice include nickel, palladium,
There are cerium and the like, those belonging to the body-centered cubic lattice include Group 5A metals such as vanadium, niobium and tantalum, and those having a hexagonal closest packed structure include titanium, zirconium, magnesium and lanthanum. In these metal hydrides, the hydrogen atoms penetrating into the metal are located in gaps (lattice intervals) between regularly arranged metal atoms.

The case of a hydrogen storage alloy is as follows. For example, a Ti—Ni-based alloy is composed of Ti ₂ Ni and T
In iNi, they are a face-centered cubic lattice and a body-centered cubic lattice, respectively. The TiFe alloy is a body-centered cubic lattice, and has a structure in which Fe atoms and Ti atoms alternately occupy the center of the cube. The position where hydrogen enters is an octahedral lattice gap surrounded by two Fe atoms and four Ti atoms. The structure of LaNi ₅ is hexagonal, and its hydrogen storage sites are octahedral and tetrahedral lattice gaps formed when La and Ni atoms are stacked. There is also a restriction on the distance between H and H, so that six hydrogen atoms can enter the unit cell.

On the other hand, among the AB binary alloys, there is a group of alloys called Laves phase alloys represented by the AB ₂ type composition formula, where the A atom has a large atomic radius and the B atom is small. This type is an alloy that absorbs a large amount of hydrogen.
n ₂ (C14), ZrV ₂ (C15 type), ZrCr ₂ (C
14) and ZrMn ₂ (C14). These crystal structures have a cubic MgCu structure as shown in FIG.
₂ (C15 type) and hexagonal MgZn ₂ (C14 type) as shown in FIG. In FIG. 7, represents an A atom, and ● represents a B atom.

The photocatalyst / water decomposing device 50 decomposes water by sunlight, and uses a circuit shown in FIG. That is,
FIG. 8A shows the current of a bipolar photovoltaic cell under irradiation of sunlight.
Voltage characteristics are shown, and a potential range of V = 0 to Vcc is a region where the photoelectrode system works on an external circuit, and an electromotive force is generated in this region. FIG. 8B shows a photocurrent-potential characteristic of a triode system, where characteristic A is an n-type semiconductor and characteristic B
Is a p-type semiconductor, and an open circuit electromotive force Vcc corresponding to the difference between the flood band potentials Vfb of A and B is obtained. 8A can be obtained from FIG. 8B by using the fact that the currents flowing through the characteristics A and B are equal and that the potential difference is V.

At present, the photo-anode material having the best characteristics is titanium oxide (TiO ₂ ). Since the forbidden band Eg of this semiconductor is about 3 eV, only short-wavelength light of 400 nm or less is absorbed by TiO ₂ . . In an n-type semiconductor, the flat band potential Vfb (Fermi level) is almost equal to the position of the conductor.
Is an important quantity. As shown in FIG. 8B, the flat band potential Vfb substantially corresponds to the rising potential of the photocurrent. In the case of an n-type semiconductor, the rising of the photocurrent becomes more negative as the flat band potential Vfb becomes more negative. High electromotive force can be obtained even in combination.

On the other hand, in a p-type semiconductor, a reduction reaction occurs because electrons generated by light absorption come to the electrode surface.
At this time, hydrogen is generated from water as described below.

III V compound semiconductors such as H ⁺ + e → H ₂ H ₂ O + e → H ₂ + OH ^— GaP, GaAs, InP,
Group IV element semiconductors such as Si are the main p-type materials, and CdTe and the like are both n-type and p-type in IIVI compounds.

Next, the fuel cell 60 is operated at a high temperature using an ion-conductive oxide as an electrolyte, and the high-temperature operation lowers the theoretical energy efficiency, but improves the energy recovery rate by the bottoming cycle. . The ionic conductivity of the electrolyte is obtained by oxygen ions (O ²⁻ ), protons (H ⁺ ) or both. FIG. 9 shows the operating principle of the fuel cell when the electrolytes are different. The anode reaction and the cathode reaction in the case of oxide ion conductivity and the case of proton conductivity are as follows.

In the case of oxide ion conductivity, anodic reaction H ₂ + O ²⁻ → H ₂ O + 2e Cathodic reaction 1 / 2O ₂ → O ²⁻ + 2e In the case of proton conductivity, anodic reaction H ₂ → 2H ⁺ + 2e cathode reaction 2H + 2e + 1 / 2O ₂ → H ₂ O When a conductive electrolyte mixed with oxygen ions and protons is used, the above reaction occurs simultaneously. FIG. 10 shows a fuel cell having a cylindrical cell structure, in which four cylindrical cells are arranged between an air electrode bus and a fuel electrode bus via an interconnector.

[0024]

As described above, according to the ultra-compact clean power generation system of the present invention, inexpensive natural wind power and sunlight are used as energy sources.
There is no concern that resources will be depleted in the future, and there is no need to worry about air pollution because the exhaust gas is oxygen, and there is the advantage of being clean energy. In addition, since the entire system can be downsized, it can be easily installed in each home, and it will solve future international energy problems. It can be used for daily energy use in households, shared use in buildings and apartments, as a temporary energy source for several days in emergencies, and as an energy source in remote areas and isolated islands.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the concept of the present invention.

FIG. 2 is a flowchart showing the relationship between detection and control in the present invention.

FIG. 3 is an external view showing an example of a horizontal axis windmill.

FIG. 4 is an external view showing an example of a vertical axis windmill.

FIG. 5 is a principle diagram of water splitting by an electrolytic process using a solid polymer electrolyte.

FIG. 6 is a view showing an example of a crystal structure of a hydrogen storage metal.

FIG. 7 is a view showing an example of a crystal structure of a hydrogen storage alloy.

FIG. 8 is a diagram for explaining decomposition of water by a photocatalyst.

FIG. 9 is a principle diagram showing a power generation principle of a solid oxide fuel cell.

FIG. 10 is a schematic structural view of a cylindrical cell fuel cell.

[Explanation of symbols]

 Reference Signs List 10 wind power generator 20 rectifier 30 electrolyzer 40 hydrogen storage unit 50 photocatalyst / water splitter 60 fuel cell 70 controller 80 display

Claims (6)

[Claims] 1. A wind power generator for generating AC power by wind power, a rectifier for converting AC power from the wind power generator to DC power, and an electrolyzer for electrolyzing water by DC power from the rectifier. An apparatus, a photocatalyst / water splitter for electrolyzing water by sunlight and a photocatalyst, a hydrogen storage unit for storing hydrogen gas generated from the electrolyzer and the photocatalyst / water splitter, and the hydrogen storage unit And a fuel cell for converting hydrogen gas stored in the fuel cell into DC power. 2. The ultra-compact clean power generation system according to claim 1, further comprising a control device for integrally controlling the wind power generation device, the rectification device, the electrolysis device, the hydrogen storage unit, and the fuel cell. 3. The ultra-small clean power generation system according to claim 2, wherein the control device includes a display device so as to monitor the operation status of each unit. 4. The method according to claim 1, wherein the AC power is generated by wind power, the AC power is converted to DC power, and hydrogen gas obtained by electrolyzing water by the DC power is supplied to a fuel cell to obtain DC power. Ultra-compact clean power generation system. 5. An ultra-small clean power generation system, characterized in that hydrogen gas obtained by electrolyzing water with sunlight is supplied to a fuel cell to obtain DC power. 6. An ultra-small clean power generation system, wherein the hydrogen gas according to claim 4 or 5 is temporarily stored in a storage unit and then supplied to the fuel cell.