JP2003134700A - Energy supply network using solar light pumped laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve environmental problems caused by the conventional power generation method by use of natural solar energy, and to provide a system to supply solar energy from a remote place to a place of consumption efficiently. SOLUTION: In this energy supply network which uses solar light pumped laser, means of generating a solar light pumped laser which can absorb energy of a wide band spectrum and oscillate it as laser is installed at a location easy to secure space such as in outer space. The laser enables to transmit energy to a remote distance efficiently as highly directional laser by reflecting, controlling and transmitting to the destination at a facility outside the earth such as satellites stationed at places in the network. In the area where laser absorption loss is large due to the atmosphere, the laser is irradiated to an airship floating in the stratosphere, converted to microwave on the airship, and transmitted to the power network on the ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for utilizing natural energy, and relates to an energy supply network system for directly generating a laser from sunlight which is a natural energy and supplying the energy to a destination by the laser having a good directivity. .

[0002]

2. Description of the Related Art In a society that consumes a large amount of energy, a network that efficiently transmits energy is required. Currently, there is an electric power transmission grid as a typical example of an energy supply network on the ground. This power grid is a power plant
Electric power is supplied over a wide area from a power transmission network (thermal power, nuclear power, hydraulic power, etc.), but there is a problem that the loss due to the power transmission line is large and the installation location is limited to the ground. Also, in thermal power generation, there is a problem of air pollution such as CO ₂ , NOx, SOx emission from the use of fossil fuels, in nuclear power generation, the treatment of nuclear waste, and in hydropower generation, it is regarded as a problem from the viewpoint of forest and river protection. ing. Attention is being focused on power generation using so-called environmentally friendly natural energy. Photovoltaic power generation, which extracts energy from sunlight, is regarded as a promising technological means among power generation methods using natural energy, and there is a track record of solar cells being widely used. When supplying power by solar power generation, the issue is to secure the installation location of power generators and power transmission equipment. Since the energy density of light sent from the sun is low, a large light receiving area is required to supply a large amount of energy.
It is difficult to secure the space in the suburbs of a large power consumption area such as the city, and it can be secured only in a place away from the power consumption areas such as outer space, the desert, and the ocean. I don't get it. However, in order to transport electric power from such remote areas, it is necessary to rely on a power grid, and the power supply through the grid is lossy, inefficient, and costly for installation. The cost for will be higher.

As a method that does not rely on the power grid, a method shown in FIG.
There is a method of generating a microwave with the obtained electric power and transmitting energy using the microwave as shown in FIG. This method uses a solar cell to convert sunlight to electric power and electric power to microwave, and two energy conversion processes, so the system becomes large and the directivity of the microwave is increased. However, this is a system with a lot of loss when constructing a long-distance energy supply network, which is disadvantageous in terms of transmission efficiency. On the other hand, there is a method of using a laser with good directivity for energy transmission, but in order to generate a laser by the existing method,
As shown in FIG. 3B, sunlight must be converted into electric power by a solar cell, and the electric power must generate a laser. In this case, the system becomes complicated and large because electricity is generated from sunlight and a laser is oscillated and generated from the generated electric power, which makes the system complicated and large. There is a problem that it becomes large. Further, there is a semiconductor laser that irradiates a semiconductor with light and optically excites it as a technical means capable of directly converting the sunlight into a laser without using electric power, but this method (C in FIG. 3) is a laser unit. It has only been ground-tested at, and the idea of applying it in space or incorporating it into a laser energy supply network has not yet been made.

[0004]

The object of the present invention is to solve the environmental problems of the conventional power generation system by using natural energy using sunlight, and to efficiently generate the energy generated from sunlight from a remote location. The purpose is to build and provide a system for supplying to the consumption area.

[0005]

The energy supply network using the solar light pumped laser according to the present invention is a solar light pumped laser generating means capable of absorbing energy of a wide band spectrum and oscillating as a laser in space such as outer space. Installed in a place where it is easy to secure
The laser is reflected and controlled by an extraterrestrial facility such as a satellite arranged in various places of the network and transmitted to a destination, thereby enabling highly efficient long-distance energy transmission by the laser having high directivity. Further, in the region where the loss of laser absorption due to the atmosphere is large, a method is adopted in which an airship floating in the stratosphere is irradiated with a laser, converted into microwaves on the airship, and then sent to a power grid on the ground.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a large area solar light receiving surface is required to acquire a large amount of solar energy, so that the facility requires a vast space. Considering that it is difficult to secure a facility construction site not only in a large energy consumption area such as an urban area but also in a land area where people live, such as cultivated land, space space is considered as a powerful construction site along with the desert area and the sea. First, the overall configuration of the system of the present invention in which a solar energy acquisition station is installed in outer space will be described with reference to FIG. In the figure, 1 is a solar energy acquisition station that has a wide-area solar light receiving surface that is spread out in space.
Is a laser relay station, 3 is an airship, 4 is an artificial satellite, 5 is an aircraft, 6 is a space platform, 7 is a lunar base, 8 is a spacecraft such as a rocket, and 9 is an artificial object such as a waste satellite. Debris, 10 shows lunar orbiting satellites, and 11 shows manned missions to Mars. Energy is acquired at the solar energy acquisition station 1, but the system is not a method of converting power into electricity using a solar cell that is generally adopted as a solar energy acquisition method, but a method of directly emitting laser light from sunlight. Is. A laser is an energy source that applies energy to the laser material from the outside, and once the electrons of the substance are excited and returned to their original orbital state, they are emitted as light energy concentrated in one spectral line, causing the light to resonate. It is a strong collierent light oscillated by the vessel structure. Two types of light irradiation and current injection are generally used to apply energy from the outside. The solar light pumped laser used in the present invention is the former light irradiation method, in which energy is injected into the laser material by irradiation of sunlight. , A resonator structure is provided to oscillate. For example, a commercially available YAG laser using a Nd: YAG crystal in which a neodymium is doped in a yag crystal is used as a light from a normal lamp or a semiconductor laser.
1.06 μm by hitting a crystal and giving it a resonator structure
Is oscillating and outputting the light. Shine sunlight on this crystal,
It has been proved that 1.06 μm light can be similarly oscillated by providing a resonator structure. In order to increase the efficiency of the laser, that is, the ratio of the laser output energy to the energy injected from the outside, it is desired that the energy absorption rate of the laser material and the energy concentration in the laser oscillation spectrum are both high. The solar light pumped laser can be a highly efficient laser by having a multiple structure capable of polychromatic absorption matching the spectrum of sunlight and a structure for concentrating absorbed energy in the laser oscillation region. Solar energy acquisition station 1
The energy converted by the laser into the form of light is
It is sent to the laser relay station 2 and used for various energy supplies. It should be noted that this solar energy acquisition station 1 is not limited to one, and lasers are collected from many stations 1 to this laser relay station 2. The great technical significance of the present invention is that energy transmission to a distant place is performed in the form of transmission and reception of laser light. First, it has the advantage that it can be transmitted directly to a remote location in space without the need for mediation equipment such as cables. In that respect, it can be said that electromagnetic waves such as microwaves are similar, but in the case of electromagnetic waves, there is a problem of directivity, and there are inevitably large losses, resulting in low transmission efficiency. Therefore, the transmission efficiency can be made very high.

This laser is used as an energy source. One is a laser relay station 2 relaying the laser as it is to a spacecraft 3 above the terrestrial energy base, and converting it into electric power at the terrestrial base to convert it to terrestrial power. A form in which power is supplied through a power cable can be realized. Lasers sent from solar-excited lasers in space are converted to electric power using solar cells on the ground. Solar cells are usually made to absorb a wide spectrum of sunlight,
In the present invention, high energy conversion efficiency is achieved by using a solar cell having a structure that selectively absorbs the wavelength of the sunlight-excited laser. In addition, a method is also used in which a laser is once received by an airship, converted into microwaves, and transmitted to a rectenna on the ground that converts microwave energy into DC power. This is a measure against scattering of laser light in the atmosphere and reduction of transmission efficiency in rainy weather. The weak point of laser transmission is a light transmission obstacle, but on the ground, this obstacle may occur depending on weather conditions, so that it is possible to select the one with higher transmission efficiency. The microwave received by the rectenna on the ground is converted into electric power and connected to the commercial power grid. In addition to the method of transmitting power by microwave as a countermeasure against the above propagation obstacles, the laser received by the airship is sent to the ground via the optical fiber and converted into electric power using the solar cell,
A method of connecting to the terrestrial power network can also be adopted. This method involves the problem of installation and maintenance of the fiber cable, but the loss is small and the transmission efficiency is extremely high.

The form of transmitting and utilizing the laser as an energy source presented by the present invention is also a form of supplying energy to other aircraft 4 such as satellites 4 or space platforms 5 or airplanes 6 that are used on the ground and are flying away from the ground. is there. These transmit energy in the form of laser from the laser relay station 2 to the aircraft that is navigating off the ground such as the satellite 4, the space platform 5 or the airplane 6 and converting the laser into electric power by the solar cells in these navigating aircraft. Is what you use. This also uses a solar cell having a structure that selectively absorbs the wavelength of the received laser in order to achieve high energy conversion efficiency. It has already been proposed to transfer energy in the form of microwaves from a satellite that is irradiated with sunlight between satellites to a satellite that is in the shadow of the earth so that the energy can be exchanged (Japanese Patent Laid-Open No. 2000-278888). However, since the present invention is a method of transmission using a laser having good directivity, it is far superior in terms of transmission efficiency. Energy transmission from the laser relay station 2 to the lunar base 7 and lunar orbiting satellites that will be installed in the future can also be realized by the laser irradiation and light receiving system of the present invention. Furthermore, this lunar base 7 is a manned mission to other planets such as Mars.
It can serve as a laser relay station for supplying energy to 11.

As a modification of the mode in which the laser presented by the present invention is transmitted and used as an energy source, not only is it finally converted into conventional energy such as electric power and used as described above, but also the laser Objects existing in outer space, for example, spacecraft such as rockets (OT)
V) It is possible to realize a usage mode in which the propulsive force is applied to the debris 9 and the debris 9. Debris refers to artificial flying objects such as artificial satellites that are no longer useful and cannot move autonomously. Debris is, so to speak, like dust in the space, and is an annoying entity that may be collided with other spacecraft. The use of the invention for debris is to launch a laser towards this debris 9 in the energy supply network, for example from a laser oscillator of the laser relay station 2. Then, the surface of the debris is heated and the surface substance is converted into plasma gas.
By the reaction of the plasma generated in this way, the debris orbit is changed and moved to a place where it does not interfere with the operation of other satellites, or it enters the atmosphere and disappears. Since the energy supply network of the present invention has a wide global coverage, it can be used to remove debris flying in various orbits.

Propulsion energy can also be supplied to the space navigation vehicle (OTV) 8 such as a rocket by emitting a laser from the laser oscillator of the laser relay station 2 in the energy supply network. O
The TV 8 is irradiated with a laser beam to heat the propellant and turn it into plasma to obtain propulsion. The applicant has previously proposed this technique in Japanese Patent Laid-Open No. 2001-132542. In the conventional chemical rocket, which depends only on the energy of the fuel for propulsion energy, this method using a laser can supply abundant energy to the spacecraft. It is not necessary to use so-called fuel as the propellant, and water or the like that exists in the body and is easy to handle can be used for it. A propellant container is irradiated with a laser to generate plasma, and an injection engine equipped with a nozzle for ejecting the generated plasma to the outside of the machine is operated. The principle of obtaining the propulsive force by the reaction of the generated plasma is the same as that of the debris 9 described above. When irradiating the OTV 8 with a laser, the number and the position of the laser devices are considered to be problems, but the problem of the number and the position is cleared by using a number of laser oscillation devices located in the energy supply network.

[0011]

[Examples] A specific example of a mechanism of converting sunlight into a laser beam and extracting the laser beam, which is performed in a solar energy acquisition station, will be described. The one shown in FIG. 2 is a laser unit, and a large number of these units are arranged to constitute a solar energy acquisition station. The laser unit 20 has a wide area light receiving section 21 for receiving sunlight, a condenser section 22 for condensing the sunlight, and an optical amplification medium 23 at the condensing position to excite the laser and A resonance part 24 for resonating and strengthening the excited laser, a transmitter part 25 for taking out a part of the laser in the resonance part 24 and sending it to the outside, and a radiator part having a fin structure for suppressing heat generation in the resonator. It consists of 26. A large number of such laser units 20 are arranged and arranged in a matrix form or the like so that the panel-shaped light receiving unit can receive the sunlight most efficiently. Each unit generates laser light, and the laser extracted from each unit is condensed and sent from the solar energy acquisition station 1 to the laser relay station 2.

[0012]

Since the present invention basically uses solar energy as an energy source, it suppresses the use of fossil fuels, that is, CO ₂ emissions, contributes to the solution of environmental problems, and is an inexhaustible sun. By extracting energy, we solve energy problems that are becoming more serious. The energy supply network of the present invention includes means for directly generating and emitting a laser upon receiving excitation of sunlight, means for relaying the emitted laser light, and means for receiving the relayed laser light as an energy source. Therefore, the solar energy acquisition system can be made compact because it is directly converted into a laser for transmission without being converted into electric power and then converted into a transmission wave as in the conventional method. , Materials can be easily transferred and constructed in remote areas such as outer space, desert areas or the sea. Also,
Since the energy transmission form is laser radiation and light reception, spatial propagation that does not require a medium such as a cable is possible, and laser directivity is superior to microwave transmission, which has the same effect. Energy supply with good propagation efficiency can be realized. By directionally transmitting energy to where it is needed, it can revolutionize energy supply.

In the energy supply network by the solar light pumped laser of the present invention, means for directly generating and emitting a laser upon receiving the excitation of sunlight is installed in outer space, and a means for relaying the emitted laser light is an artificial satellite. Since this is a space-scale network that uses off-ground facilities such as space stations, aircraft, and airships, multiple facilities complement each other to provide constant energy even when part of the facility is behind the earth and is not exposed to sunlight. Can be realized. Since the sunlight is received in outer space without atmosphere, the wavelength light component in a region that is shielded in the atmosphere can be effectively utilized for laser excitation. Further, the energy supply network by the solar light pumped laser of the present invention receives the laser energy converted from sunlight through a relay facility outside the ground, such as a spacecraft, an airship, an aircraft, a ship, and a vehicle, and converts it into an electric quantity. Since the means and the means for sending the quantity of electricity to the power grid are provided in the ground base, it is possible to use the laser energy generated in outer space as ground power. Further, since the laser has a constant wavelength, it is possible to realize highly efficient power conversion by matching the characteristics of the solar cell that converts the laser to electric power with the laser wavelength. Energy of the present invention provided on the ground base with means for converting a laser into a microwave on the off-ground relay facility, means for receiving the microwave and converting it into an electric quantity, and means for sending the electric quantity to a power grid The supply network can switch to a more efficient transmission system when the spatial transmission loss of the laser is large due to atmospheric conditions.

The energy supply network of the present invention comprises:
It can be applied to provide propulsion to space-space materials. That is, when the laser from the solar energy acquisition station equipped with means for directly generating and emitting a laser in response to the excitation of sunlight installed in the outer space is irradiated to the debris via the laser relay station, The debris orbit can be changed by the reaction of the plasma generated on the surface and changed to a place where it does not hinder the operation of other satellites, or the debris can enter the atmosphere and disappear. Further, for the OTV, a propulsion energy can be supplied by emitting a laser from a laser oscillation device of a laser relay station in the energy supply network. The OTV is irradiated with a laser beam, and a propellant such as water that exists in the body and is easy to handle is heated and turned into plasma to obtain propulsion. In the conventional chemical rocket, which depends only on the energy of fuel for propulsion energy, this method using a laser makes it possible to supply abundant energy to a spacecraft.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an entire system of a solar pumped laser network of the present invention.

FIG. 2 is a diagram showing a method of acquiring and transmitting energy from sunlight, where A is a microwave energy transmission method, B is an existing laser energy transmission method, and C is a method of the present invention.

FIG. 3 is an example of a laser unit installed in the energy station of the present invention.

[Explanation of symbols]

1 Solar energy acquisition station 10 Orbiting satellite 2 Laser relay station 11 Mars manned mission 3 Airship 20 Laser unit 4 Satellite 21 Solar light receiving surface 5 Platform 22 Concentrator 6 Aircraft 23 Optical amplification medium 7 Lunar surface base 24 Resonator 8 OTV 25 transmitter 9 debris 26 radiator

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayuki Shinno             1 Kanagaki, Kanazawa, Kakuda City, Miyagi Prefecture Aerospace             Kadoda Space Propulsion Technology Research Center             Within (72) Inventor Wood Plate Katsuto             1 Kanagaki, Kanazawa, Kakuda City, Miyagi Prefecture Aerospace             Kadoda Space Propulsion Technology Research Center             Within (72) Inventor Akio Moro             1 Kanagaki, Kanazawa, Kakuda City, Miyagi Prefecture Aerospace             Kadoda Space Propulsion Technology Research Center             Within (72) Inventor Tetsuo Taniuchi             2-1-1 Katahira, Aoba-ku, Sendai City, Miyagi Prefecture (72) Inventor Kazuhisa Fujita             1-16-6 Izumichuo, Izumi Ward, Sendai City, Miyagi Prefecture (72) Inventor Kazuo Imasaki             2-6 Yamadaoka, Suita City, Osaka Prefecture (72) Inventor Masakatsu Nakano             4-1-8 Honcho, Kawaguchi City, Saitama Prefecture             Inside the business group

Claims (6)

[Claims] 1. A means for directly generating and emitting a laser upon receiving excitation of sunlight, a means for relaying the emitted laser light, and a means for receiving the relayed laser light as an energy source. A network that supplies energy. 2. The energy supply network according to claim 1, wherein the means for directly generating and emitting a laser upon receiving excitation of sunlight is installed in outer space. 3. The energy supply network according to claim 1, wherein the means for relaying the emitted laser light is an off-ground facility such as an artificial satellite, a space station, an aircraft or an airship. 4. The energy supply network according to claim 3, wherein a means for receiving a laser from an off-ground relay facility and converting it into an amount of electricity and a means for transmitting the amount of electricity to a power grid are provided in the ground base. 5. A base on the ground is provided with means for converting a laser into a microwave on the off-ground relay facility, means for receiving the microwave and converting it into an electric quantity, and means for sending the electric quantity to a power network. The energy supply network according to claim 3, wherein the energy transmission system can be switched to microwave transmission when the spatial transmission loss of the laser is large due to atmospheric conditions. 6. A laser from a solar energy acquisition station equipped with means for directly generating and emitting a laser upon receiving the excitation of sunlight installed in outer space, and propelling the laser to a space navigation material through a laser relay station. An energy supply network characterized by being irradiated to impart power.