“We are now talking about the thermonuclear energy of the future and a new ecological type of fuel that cannot be produced on Earth. We are talking about the industrial development of the moon for the extraction of helium-3. This statement of the head of the Energia rocket and space corporation Nikolai Sevastyanov, if it didn’t shock the imagination of law-abiding Russians (they now, just on the eve of the new heating season, only deal with helium-3), then the imagination of specialists and interested people did not leave indifferent.

This is understandable: given the, to put it mildly, not brilliant state of affairs in the domestic aerospace industry (Russia's space budget is 30 times less than in the United States and 2 times less than in India; from 1989 to 2004, we launched only 3 research spacecraft), suddenly, like this, no more, no less - the Russians will produce helium-3 on the moon! Let me remind you that, theoretically, this light isotope of helium is capable of entering into a thermonuclear reaction with deuterium. Accordingly, fusion is considered by many scientists to be a potentially limitless source of cheap energy. However, there is a problem: helium-3 is less than one millionth of total helium on earth. But in the lunar soil, this light isotope is found in abundance: according to academician Eric Galimov, about 500 million tons ...

They say that at one time in the United States, a huge poster hung in front of the entrance to Disneyland: "We and our country can do everything, the only thing that limits us is the boundaries of our imagination." All this was not far from the truth: a fast and efficient nuclear project, a fantastically successful lunar program, a strategic defense initiative (SDI), which completely finished off the Soviet economy. ...

In essence, one of the main functions of the state, especially in the 20th century, was precisely the formulation of tasks for the scientific community on the verge of imagination. This also applies to the Soviet state: electrification, industrialization, the creation atomic bomb, the first satellite, the turn of the rivers... By the way, we had our own "poster" in front of Disneyland - "We were born to make a fairy tale come true!"

“I just think that there is a shortage in some major technological problem,” said Alexander Zakharov, Doctor of Physical and Mathematical Sciences, Scientific Secretary of the Space Research Institute of the Russian Academy of Sciences, in an interview with me. - Maybe because of this, all this talk about the extraction of helium-3 on the Moon for thermonuclear energy has recently arisen. If the Moon is a source of minerals, and from there to carry this helium-3, but there is not enough energy on Earth ... All this is understandable, it sounds very beautiful. And for this it is easy, perhaps, to persuade influential people to allocate money. I think so".

But the thing is that there is no technology on Earth right now - and in the next 50 years at least it is not expected to appear - burning helium-3 in a thermonuclear reaction. There is not even a draft design of such a reactor. The international thermonuclear reactor ITER, which is currently under construction in France, is designed to "burn" hydrogen isotopes - deuterium and tritium. The calculated temperature of "ignition" of a thermonuclear reaction is 100-200 million degrees. To use helium-3, the temperature must be an order of magnitude or two higher.

So, the head of Russia's largest rocket and space corporation, Nikolai Sevastyanov, sorry for the expression, is powdering our brains with his helium-3? Does not look like it. Why!?

“The space industry is naturally interested in such a large and expensive project,” says Alexander Zakharov. “But in terms of its practical use, it is absolutely clear that this is premature.”

To implement the helium-3 project, it is necessary to create a special program for additional exploration of the moon, launch a whole squadron of spacecraft, resolve issues with the production of helium-3, its processing ... This will ruin the country worse than any SDI.

“I don’t want to say that the Moon is completely closed from a scientific point of view - there are also scientific tasks left,” emphasizes Alexander Zakharov. - But, as they say, this should be done step by step, I do not forget about other scientific tasks. And then we somehow shied away: as soon as the Americans announced the program of a manned flight to Mars, we immediately declare that we are also ready to do this. We heard about lunar programs - let's do this too ... We do not have a deliberate, balanced, strategic national task.

Here we are again back to where we started, to the strategic national task. The trouble is that, unlike the Americans, we are limited not so much by our imagination - with this, as Nikolai Sevastyanov's statement shows, everything is in order with us. But according to the most modest estimates, the helium-3 program (let's call it that), according to the most conservative estimates, will require 5 billion dollars for five years of research.

From a purely scientific point of view, in the problem of fusion based on TOKAMAKS, even though decision about the construction of the international experimental reactor ITER, there has been a certain stagnation. (However, this is a topic for a separate discussion.) It seems to me that the helium-3 problem for some part of the influential thermonuclear lobby is a new niche for resuscitation and the realization of professional ambitions.

Not only that - and this is quite a sensational thing, and the only reason I did not start my article with it - as we were told by an expert from the aerospace industry, the Russian project for the extraction of light helium isotope on the Moon has been allocated ┘ 1 billion dollars! This money, allegedly, is of American origin.

Despite all the intricacy of such a combination, the ends meet in it quite successfully. To secure $104 billion for the recently announced lunar base program, the US National Aeronautics Agency and space research it was necessary to show that "strategic competitors" are also on the alert. That is, the "Russian" billion is, in a way, NASA's overhead... Hence the surge of interest in helium-3 production in Russia, inexplicable by rational motives.

If this is true, then once again we will all have to verify the validity of the formula published ten years ago in the journal Physics Today. Here it is: "Scientists are not disinterested seekers of truth, but rather participants in a fierce competition for scientific influence, the winners of which break the bank."

In recent months, the media have been talking a lot about the existence of a number of states (primarily the United States, Russia and China) of projects for the production of helium-3 for controlled thermonuclear reactions. These projects are seen by many as literally the solution to all of humanity's problems. So what is helium-3?

Of all the helium atoms that exist on Earth, 99.999862% of the atoms have a mass 4 times that of a hydrogen atom. This is helium-4. Its atomic nuclei are alpha particles that are formed during radioactive decay. And the remaining 0.000138% of helium atoms are only 3 times heavier than a hydrogen atom. This is helium-3.

The ratio of helium-3 and helium-4 on the scale of the Universe is significantly different - there the number of these isotopes differs by about one order of magnitude. In meteorite matter and in lunar rocks, the content of helium-3 varies from 17 to 32% of the total amount of helium. Billions of years ago, the ratio of helium-4 to helium-3 on Earth was the same as in the entire universe. However, over the time that has passed since then, the helium formed during the primary nucleosynthesis has completely evaporated from earth's atmosphere. And all the helium that is on Earth today was formed as a result of radioactive decay. That is, on Earth there is practically only helium-4. And helium-3 is formed only on the Sun as a result of thermonuclear reactions occurring there (mainly helium-4 is formed on the Sun, but a lot of helium-3 is also formed there). From the Sun, these elements scatter into space in the form of the so-called "solar wind" (a special type of cosmic rays). The "solar wind" does not hit the Earth and other planets: the atmosphere and the magnetic field interfere. But, say, on the Moon, devoid of an atmosphere, particles of the "solar wind" fall and "get stuck" in the surface layer of the soil.

Until some time, these facts were of purely theoretical interest. On a practical level, they started talking about helium-3 when it became clear that oil would run out in the coming decades. Coal and gas will last a little longer, but also not for long. Obviously, the only way to solve the energy problem is to use the energy of the atomic nucleus. However, the reserves of uranium are also not infinite ... Therefore, the idea of ​​using thermonuclear fusion has been invariably popular for half a century.

In thermonuclear reactions taking place on the Sun, four atoms of the light isotope of hydrogen are combined into one helium atom with the release of energy. However, for thermonuclear reactions produced on Earth, the light hydrogen isotope (constituting 99.985% of all hydrogen) will not work, because the fusion reaction of light hydrogen isotopes has an extremely small cross section (reaction probability). It is this low cross section of the reaction that ensures the stability of the Sun - otherwise it would not be a stable thermonuclear reaction, but a thermonuclear explosion.

For thermonuclear reactions produced on Earth, "heavy hydrogen" - deuterium - is needed. Of the hydrogen that exists on Earth (mostly in the form of water), deuterium makes up 0.015%. It can be obtained by electrolysis plain water, in which deuterium is 0.0017% by mass. However, in addition to deuterium, a thermonuclear reaction requires a second component, the atom of which must be 3 times heavier than hydrogen. It can be either "superheavy hydrogen", which is called tritium, or the same helium-3. Tritium does not exist on Earth, in addition, it is very highly radioactive and unstable. Tritium is suitable for hydrogen bombs and experimental facilities, but not for "industrial" reactors (in hydrogen bombs, tritium is formed when lithium is irradiated with neutrons as a result of the reaction: 6 Li + n -> 3 H + 4 He). A thermonuclear reaction involving tritium is described by the following equation: 2 H + 3 H -> 4 He + n + 17.6 MeV. It is this reaction that is considered as the main one in the planned projects, in particular, in the international ITER project being created.

However, the disadvantage of such a reaction is, firstly, the need for highly radioactive tritium for it, and, secondly, the fact that strong neutron radiation occurs during such a reaction. Therefore, projects of a "neutronless" thermonuclear reaction have been created recently, for which helium-3, a light isotope of helium, serves as fuel. The equations for "neutronless" reactions are as follows:

3 He + 3 He -> 4 He + 2p + 12.8 MeV,
3 He + D -> 4 He + p + 8.35 MeV.

The advantage of reactions on helium-3 in comparison with the deuterium-tritium reaction is that, firstly, it does not require radioactive isotopes as fuel, and, secondly, the resulting energy is carried away not with neutrons, but with protons, from which it will be easier to extract energy.

The only problem is the virtual absence of helium-3 on Earth. But, as mentioned above, helium-3 is in the lunar soil. So in order to have energy sources after fossil fuels run out, the space agencies different countries are developing plans to build a base on the moon that will process lunar soil (called regolith), extract helium-3 from it and deliver it in liquefied form to thermonuclear power plants on Earth. One ton of helium-3 is enough to provide the energy needs of all mankind for several years, which will pay off all the costs of creating a lunar base. Bush has already set a goal: to create an American lunar base in 2015-2020.

And what is being done in Russia today? Here is a selection of reports from news agencies

"Russia can resume the lunar program within a few years
January 15, 2004

Russia is discussing the issue of resuming programs for the exploration of the Moon and Mars, Nikolai Moiseev, First Deputy Head of Rosaviakosmos, told ITAR-TASS. "By the end of the year, the Federal Space Program until 2015 will be developed, which may include these projects," he said. According to Moiseev, "scientists come up with many initiatives to organize expeditions to the Moon and Mars, but it is not yet known which of them will be included in the federal program."

Russia can revive the lunar program within a few years, says Roald Kremnev, First Deputy Director General of the Lavochkin Research and Production Association.
"After the curtailment of the Soviet program for the exploration of the Earth's satellite in the late 70s of the last century, we have been supporting scientific and technical developments on this topic at the modern level for more than three decades," Kremnev says. According to him, at the present time at the enterprise where the legendary "Lunokhod" was created, "there is a serious backlog on lunar automata." The creation and launch of such a device, according to Kremnev, will cost 600 million rubles.

Lunar energy sources can save the Earth from a global energy crisis, academician Eric Galimov, a member of the Bureau of the Space Council of the Russian Academy of Sciences, believes. Tritium mined on the Moon and delivered to Earth can be used for thermonuclear fusion, the scientist claims.
Source: NEWSru.com

Russian scientist proposes to rake miracle fuel from the moon with bulldozers
January 23, 2004

Academician Russian Academy Sci., member of the bureau of the RAS Space Council, Eric Galimov, believes that it is necessary to immediately begin preparations for the extraction of lunar fuel, ITAR-TASS reports. Production of helium-3 on the Moon and its removal from there by spacecraft, in his opinion, can be started in 30-40 years.

"In order to provide all mankind with energy for a year, only two or three flights are needed. spaceships with a carrying capacity of 10 tons, which will deliver helium-3 from the moon... The cost of interplanetary delivery will be ten times less than the cost of electricity currently generated at nuclear power plants," Galimov said.

According to the scientist, the delivery of the substance can begin in 30-40 years, but it is necessary to start work in this area now. According to him, the development of the project "will require only 25-30 million dollars." The scientist proposes to collect helium-3 from the lunar surface with special bulldozers.
Source: Lenta.ru

On the last week In his speech on the new US space program, President Bush announced that a permanent base should be established on the Moon, which would be the first step towards further human space exploration. He also said that lunar soil could be recycled to produce rocket fuel and breathable air.

Bush cited two ways to recycle lunar soil as examples, but the list of lunar minerals is actually quite long... The silicon found in lunar soil can be used to make solar panels, iron - for various metal structures, aluminum, titanium and magnesium - to create a ship that will go into space away from the Earth.
And, of course, they are going to extract the helium-3 isotope on the Moon, which is very rare on Earth, and its production under terrestrial conditions is very expensive.

(adapted from SiliconValley.com)

In March 2003, the leadership of the Chinese space program officially announced the start of work on sending a research probe to the moon. Recently scientific director During this project, Ouyang Ziyuan, Academician of the Chinese Academy of Sciences, announced that already at this first stage of lunar exploration, China expects to make a great contribution to science and to the development of space technologies. So the Chinese lunar project promises to quickly pay for itself.

The first phase of China's lunar exploration program will, among other things, measure the thickness of the lunar soil, estimate the age of the surface, and determine the amount of helium-3 available there (a very rare isotope of helium found on Earth that can be used as fuel for a fusion reactor)
(based on SpaceDaily materials)

Interesting thoughts about space programs, needed to obtain helium-3 reserves, are given in the article of the candidate of technical sciences, corresponding member of the Academy of Cosmonautics. K. E. Tsiolkovsky Yuri Eskov "For clean fuel - to Uranus, published in " Russian newspaper", April 11, 2002. The author writes that it is even more efficient than on the Moon to search for helium-3 in the atmospheres of distant giant planets, for example, Uranus, where helium-3 is 1:3000 (which is a thousand times more than in the lunar On the author's suggestion, "The production of helium-3 and its delivery to the Earth should be carried out by unmanned disposable space vehicles ("tankers"), the electronuclear engine of which with a power of 100,000 kW operates throughout the entire two-way flight. In 10 years, the device will overcome difficult an imaginable distance of 6 billion km Note that an engine capable of covering such a gigantic distance in an acceptable time (10 years) can only operate on nuclear energy using the same fuel as current nuclear power plants (in principle, you can fly on solar batteries, but then the device will weigh hundreds of thousands of tons); moreover, the said engine is environmentally very “dirty”. uh, so no environmental issues for the population of the Earth it does not create.

The uninterruptible supply system for ground-based TNPPs with a total capacity of 3 billion kW will consist of periodically (four times a year) "tankers" launched from near-Earth orbit. The vehicle will only have enough fuel for one way: it will fly to the target with empty tanks. Having flown to Uranus and entering an orbit within the planet's atmosphere, the “tanker” will start operating in the plant mode for dividing the surrounding atmosphere into components: it will separate commercial helium-3 and hydrogen from liquefied gas, which is used as fuel for the return flight; most of the hydrogen and all of the ordinary helium will be dumped overboard. Thus, return refueling (without which the task of returning is unrealizable) turns out to be in fact free. As a result of the flight, 70 tons of liquid helium-3 will be delivered to near-Earth orbit; there will be about 40 "tankers" on the Earth-Uranus route at any given time.

A natural question arises: to what extent can the technologies existing today ensure the functioning of such a system? Answer: most of these elements are available, as they say, “in hardware”, the rest are at the level of far advanced design developments, partially brought to the experimental stage. The main problem here is the onboard power plant. To date, a huge positive experience has been accumulated in the creation and operation of ground-based nuclear power plant reactors with a capacity of 4 million kW with a resource of up to 30 years; the power of nuclear submarine reactors reaches 100,000 kW with a resource of tens of years, there is also domestic experience in the creation and operation of unique small-sized nuclear installations for spacecraft with a power of up to 100 kW high-temperature reactors for space nuclear engines were tested both in the USA and in the USSR. As for the size of the launched unmanned vehicle (450 tons, including 200 tons of fuel), it corresponds in order of magnitude to the mass of the ISS (and in the final project, the mass of the ISS is planned to be even larger); the total annual cargo flow into orbit (1900 tons) is less than that planned for standard programs (space communications, television broadcasting, etc.). The vast majority of the elements of such an orbital helium-hydrogen plant already exist today and are successfully operating in the cryogenic industry.” The author says that even with the current level of technology development, such a project would be quite economically viable: “The selling price of electricity in the world is from 5 to 10 cents per kW. h. From the simplest arithmetic it is clear that the delivery of helium-3 from Uranus will remain profitable even at a price of 1 ton of 10 billion dollars. The cost of launching one such plant into orbit is $10 million per ton (by the way, this is the current price of gold), and in the short term reusable carriers will reduce this price to $1 million per ton of output cargo.”

It has become commonplace to say that knowledge-intensive industries (nuclear, space, etc.) are the locomotive of the economy. The case with helium-3 is the same case. This method, which will solve energy problem for a sufficiently long time, if there are opportunities to find funds for its implementation, it can become a chance for the progress of Russian science-intensive industries: both astronautics (which is a subject for a separate discussion) and thermonuclear technology.
At the moment, there are two main directions in thermonuclear fusion: tokamaks and laser fusion. The first of these options is currently being implemented in the project of the international experimental thermonuclear reactor ITER. This reactor is designed according to the “tokamak” scheme (which means an abbreviation for the phrase “Toroidal Chamber with Magnetic Coils”). The principle of operation of a tokamak is as follows: an electric current is created in a plasma bunch, and at the same time, like any current, it has its own magnetic field - the plasma bunch, as it were, becomes a magnet itself. And then, with the help of an external magnetic field of a certain configuration, a plasma cloud was suspended in the center of the chamber, not allowing it to come into contact with the walls. There are always free ions and electrons in the gas, which begin to move in a circle in the chamber. This current heats the gas, the number of ionized atoms grows, the current strength increases and the plasma temperature rises simultaneously. This means that the number of hydrogen nuclei that have merged into a helium nucleus and released energy is increasing. However, experiments begun almost fifty years ago at the Moscow Institute of Atomic Energy showed that the plasma suspended in a magnetic field turned out to be unstable - the plasma clot "decayed" very quickly and fell out onto the walls of the chamber. It turned out that a combination of a number of complex physical processes leads to instability. In addition, it turned out that the time of stable plasma confinement increases with the size of the setup. The largest domestic machine TOKAMAK-15 already has a toroidal vacuum chamber with an outer "donut" diameter of more than five meters. Large research tokamaks were built in Russia, Japan, the USA, France, and England. And a few years ago, experts came to the conclusion that the remaining unresolved problems should be investigated at a facility as close as possible to a real power thermonuclear reactor. This understanding led to the creation of ITER. This variant of conducting a controlled thermonuclear reaction differs from all other installations and methods primarily in that it has basically gone beyond the realm of doubts and searches. Thanks to the vast database of physical and engineering data accumulated over fifty years of research, he came close to the stage of an experimental reactor. This, apparently, inspired the international community to create ITER - scientists decided that even a rich country does not make any sense to build a thermonuclear reactor alone - the result will be knowledge and experience that will still become common property and will not immediately contribute anything to the national economy. At the same time, by joining forces, you can dramatically accelerate the progress towards your working fusion and reduce your own costs. Therefore, in 1992, an agreement was signed on the joint technical design of the ITER reactor under the auspices of the IAEA. And its conceptual design at the initiative of our country began four years earlier. The ITER design team included specialists from the European Union, Russia, the USA and Japan.
Another direction on the way to a controlled thermonuclear reaction is laser thermonuclear fusion (LTF). It lies in the fact that the target of the "raw material" for a thermonuclear reaction is irradiated from all sides by laser beams, and thus conditions are created there that are sufficient for the implementation of a thermonuclear reaction. The difficulty is how to implement it technically. My dissertation work consists in carrying out computer simulation of the phenomenon of optical resonance in spherical targets under laser irradiation. Calculations show that, under certain conditions, an energy concentration occurs in an optical target, at which the conditions necessary for a thermonuclear reaction may arise.

The state that masters the technology of thermonuclear fusion, this technology before others, will receive huge advantages over others. In order for Russia not to remain on the outskirts of civilization and take part in the development of these projects, the political will of the leadership of the state is needed, much like it was with the Soviet nuclear and space projects in the middle of the twentieth century.

Candidate of Physical and Mathematical Sciences A. PETRUKOVYCH.

With the light hand of the American president, at the end of 2003, the issue of new goals for mankind in space was put on the agenda. The goal of building a manned station on the Moon, among other proposals, is partly based on the tempting idea of ​​using the unique lunar reserves of helium-3 to generate energy on Earth. Whether lunar helium is useful or not, the future will show, but the story about it is quite fascinating and allows us to compare our knowledge of the structure of the atomic nucleus and the solar system with the practical aspects of energy and mining.

Science and life // Illustrations

Science and life // Illustrations

Science and life // Illustrations

Science and life // Illustrations

Science and life // Illustrations

Science and life // Illustrations

Science and life // Illustrations

WHY? OR NUCLEAR FUSION - ALCHEMY IN REALITY

Turning lead into gold was a dream of medieval alchemists. As always, nature turned out to be richer than human fantasies. Nuclear fusion reactions created all the diversity chemical elements laying the material foundations of our world. However, fusion can also provide something much more valuable than gold - energy. Nuclear reactions in this sense are similar to chemical reactions (i.e., molecular transformation reactions): each compound substance, whether it be a molecule or an atomic nucleus, is characterized by the binding energy that must be spent to destroy the compound, and which is released when it is formed. When the binding energy of the reaction products is higher than that of the starting materials, the reaction proceeds with the release of energy, and if you learn how to take it in one form or another, the starting materials can be used as fuel. Of the chemical processes, the most effective in this sense, as you know, is the reaction of interaction with oxygen - combustion, which today serves as the main and irreplaceable source of energy at power plants, in transport and in everyday life (even more energy is released during the reaction of fluorine, especially molecular fluorine, with hydrogen ; however, both fluorine itself and hydrogen fluoride are extremely aggressive substances).

The binding energy of protons and neutrons in the nucleus is much greater than that which binds atoms into molecules, and it can be literally weighed using Einstein's great formula E = mc 2: the mass of the atomic nucleus is noticeably less than the masses of the individual protons and neutrons that make it up. Therefore, a ton of nuclear fuel replaces many millions of tons of oil. However, fusion is called thermonuclear fusion for a reason: in order to overcome the electrostatic repulsion when two positively charged atomic nuclei, you need to properly disperse them, that is, heat the nuclear fuel to hundreds of millions of degrees (recall that temperature is a measure of the kinetic energy of particles). In fact, at such temperatures we are no longer dealing with gases or liquids, but with the fourth state of matter - plasma, in which there are no neutral atoms, but only electrons and ions.

In nature, such conditions suitable for fusion exist only in the interiors of stars. The sun owes its energy to the so-called helium cycle of reactions: the synthesis of a helium-4 nucleus from protons. In giant stars and in supernova explosions, heavier elements are also born, thus forming the whole variety of elements in the Universe. (True, it is believed that part of the helium could have been formed directly at the birth of the Universe, during the Big Bang.) The sun in this sense is not the most efficient generator, because it burns for a long time and slowly: the process is slowed down by the first and slowest reaction of deuterium fusion from two protons. All of the following reactions are much faster and immediately devour the available deuterium, processing it into helium nuclei in several stages. As a result, even if we assume that only one hundredth of the solar matter in its core participates in the fusion, the energy release is only 0.02 watts per kilogram. However, it is precisely this slowness, explained primarily by the small, by stellar standards, mass of the luminary (the Sun belongs to the category of subdwarfs) and ensuring the constancy of the flow of solar energy for many billions of years, we owe the very existence of life on Earth. In giant stars, the transformation of matter into energy is much faster, but as a result, they burn themselves completely over tens of millions of years, without even having time to properly acquire planetary systems.

Having decided to conduct thermonuclear fusion in the laboratory, man is going to outwit nature in this way, creating a more efficient and compact energy generator than the Sun. However, we can choose a much more easily implemented reaction - the synthesis of helium from a deuterium-tritium mixture. It is planned that the projected international thermonuclear reactor - the ITER tokamak will be able to reach the ignition threshold, from which, however, it is still very, very far from commercial use. fusion energy(see "Science and Life" No. ,, 2001). The main problem, as you know, is to keep the plasma heated to the desired temperature. Since no wall at such a temperature can escape destruction, they try to keep the plasma cloud magnetic field. AT hydrogen bomb the problem is solved by the explosion of a small atomic charge, which compresses and heats the mixture to the required condition, but this method is of little use for the peaceful production of energy. (On the prospects of the so-called explosive energy, see "Science and Life" No. 7, 2002)

The main disadvantage of the deuterium-tritium reaction is the high radioactivity of tritium, whose half-life is only 12.5 years. This is the most radiation-dirty reaction available, so much so that in an industrial reactor, the inner walls of the combustion chamber will need to be replaced every few years due to radiation destruction of the material. True, the most harmful radioactive waste, which requires indefinite burial deep underground due to the long decay time, is not formed at all during synthesis. Another problem is that the energy released is carried away mainly by neutrons. These electrically uncharged particles do not notice electromagnetic field and generally do not interact well with matter, so it is not easy to take energy from them.

Tritium-free fusion reactions, such as those involving deuterium and helium-3, are practically radiation safe because they use only stable nuclei and do not produce inconvenient neutrons. However, in order to "ignite" such a reaction, it is necessary, in order to compensate for the lower fusion rate, to heat the plasma ten times more - up to a billion degrees (simultaneously solving the problem of its retention)! Therefore, today such options are considered as the basis for future thermonuclear reactors of the second generation, following the deuterium-tritium one. However, the idea of ​​this alternative thermonuclear energy has gained unexpected allies. Proponents of space colonization consider helium-3 one of the main economic goals of the lunar expansion, which should provide humanity's need for clean thermonuclear energy.

WHERE? OR SUNNY GUEST

At first glance, there should be no problem with where to get helium: it is the second most abundant element in the Universe, and the relative content of the light isotope in it is a little less than one thousandth. However, for the Earth, helium is exotic. It is a highly volatile gas. The Earth cannot hold it by its gravity, and almost all of the primary helium that fell on it from a protoplanetary cloud during the formation of the solar system returned from the atmosphere back into space. Even helium was first discovered on the Sun, which is why it was named after the ancient Greek god Helios. It was later found in minerals containing radioactive elements, and finally fished out in the atmosphere among other noble gases. Terrestrial helium is mainly not of cosmic, but of a secondary, radiation origin: during the decay of radioactive chemical elements, alpha particles fly out - helium-4 nuclei. Helium-3 is not formed in this way, and therefore its amount on Earth is negligible and is literally calculated in kilograms.

You can stock up on helium of cosmic origin (with a relatively high content of helium-3) in the atmospheres of Uranus or Neptune - planets large enough to hold this light gas, or in the Sun. It turned out that it is easier to get close to solar helium: the entire interplanetary space is filled with the solar wind, in which 70 thousand protons account for 3000 alpha particles - helium-4 nuclei and one helium-3 nucleus. This wind is extremely rarefied, by earthly standards it is a real vacuum, and it is impossible to catch it with a net (see Nauka i Zhizn, No. 7, 2001). celestial bodies, which do not have a magnetosphere and atmosphere, for example, on the Moon, and, therefore, it is possible to empty some natural trap that has been regularly replenished for the past four billion years. As a result of plasma bombardment, several hundred million tons of helium-3 fell on the Moon during this time. If the entire solar wind remained on the surface of the Moon, then in addition to 5 grams of helium-3, on average, there would be another 100 kilograms of hydrogen and 16 kilograms of helium-4 on each square meter of the surface. From this amount, it would be possible to create a quite decent atmosphere, only a little more rarefied than the Martian one, or an ocean of liquid gas two meters deep!

However, there is nothing similar on the Moon, and only a very small fraction of the solar wind ions remain forever in the upper layer of the lunar soil - regolith. Studies of lunar soil brought to Earth by the Soviet stations "Luna" and the American "Apollo" showed that helium-3 in it is approximately 1/100-millionth part, or 0.01 gram per 1 ton. And in total, there are about a million tons of this isotope on the Moon, a lot by earthly standards. At the current level of world energy consumption, lunar fuel would be enough for 10 thousand years, which is about ten times more than the energy potential of all recoverable chemical fuels (gas, oil, coal) on Earth.

AS? OR "PER GRAM PRODUCTION, PER YEAR LABOR"

Unfortunately, there are no "lakes" of helium on the Moon; it is more or less evenly dispersed over the entire near-surface layer. Nevertheless, from a technical point of view, the mining process is quite simple and was developed in detail by enthusiasts of the colonization of the Moon (see, for example, www.asi.org).

To meet the current annual energy demand of the Earth, it is necessary to bring only about 100 tons of helium-3 from the Moon. It is this number, corresponding to three or four flights of space shuttles - shuttles, that fascinates with its availability. However, first you need to dig up about a billion tons of lunar soil - not such a large amount by the standards of the mining industry: for example, two billion tons of coal are mined per year in the world (in Russia - about 300 million tons). Of course, the content of helium-3 in the rock is not too high: for example, the development of deposits is considered cost-effective if they contain at least a few grams of gold and at least two carats (0.4 g) of diamonds per ton. In this sense, helium-3 can only be compared with radium, of which only a few kilograms have been obtained since the beginning of the 20th century: after processing a ton of pure uranium, only 0.4 grams of radium is obtained, not to mention the problems of extracting uranium itself. At the beginning of the last century, during the period of a romantic attitude towards radioactivity, radium was quite popular and known not only to physicists, but also to lyricists: let us recall the phrase of V.V. . But helium-3 is more expensive than almost any substance used by man - one ton would cost at least a billion dollars, if you convert the energy potential of helium into oil equivalent at a bargain price of $7 per barrel.

Gas is easily released from regolith heated to several hundred degrees, say, with the help of a mirror concentrating the sun's rays. Let's not forget that we still need to separate helium-3 from a much larger number of other gases, mainly from helium-4. This is done by cooling gases to a liquid state and taking advantage of the insignificant difference in the boiling points of isotopes (4.22 K for helium-4 or 3.19 K for helium-3). Another elegant method of separation is based on the use of the superfluidity property of liquid helium-4, which can independently flow through a vertical wall into an adjacent container, leaving behind only non-superfluid helium-3 (see "Science and Life" No. 2, 2004).

Alas, all this will have to be done in an airless space, not in the "greenhouse" conditions of the Earth, but on the Moon. Several mining towns will have to be moved there, which, in essence, means the colonization of the moon. Now, hundreds of specialists are monitoring the safety of several astronauts in near-Earth orbit, and at any moment the crew can return to Earth. If tens of thousands of people find themselves in space, they will have to live in a vacuum on their own, without detailed supervision from Earth, and provide themselves with water, air, fuel, and basic building materials. However, there is enough hydrogen, oxygen and metals on the Moon. Many of them can be obtained as a by-product of helium mining. Then, perhaps, helium-3 can become a profitable commodity for trade with the Earth. But since people in such difficult conditions will need much more energy than earthlings, lunar reserves of helium-3 may not seem so limitless and attractive to our descendants.

By the way, there is an alternative solution for this case. If engineers and physicists find a way to cope with the retention of ten times hotter than necessary for a modern tokamak, helium plasma (a task that now seems completely fantastic), then by increasing the temperature by only a further two times, we will "ignite" the reaction synthesis involving protons and boron. Then all problems with fuel will be solved, and at a much lower price: there is more boron in the earth's crust than, for example, silver or gold, it is widely used as an additive in metallurgy, electronics, and chemistry. Mining and processing plants produce hundreds of thousands of tons of various boron-containing salts per year, and if we do not have enough reserves on land, then in each ton sea ​​water contains several grams of boron. And the one who has a vial of boric acid in his first-aid kit can assume that he has his own energy reserve for the future.

Literature

Bronstein M. P. Solar substance. - Terra Book Club, 2002.

Lunar soil from a sea of ​​abundance. - M.: Nauka, 1974.

Captions for illustrations

ill. 1. The helium cycle of nuclear fusion reactions begins with the fusion of two protons into a deuterium nucleus. In the next stages, more complex nuclei are formed. Let's write down the first few simple reactions, which we will need in what follows.
p + p → D + e - + n
D + D → T + p or
D + D → 3 He + n
D + T → 4 He + n
D + 3 He → 4 He +2p
p + 11 Be → 3 4 He
The reaction rate is determined by the probability of overcoming the electrostatic barrier when two positively charged ions approach and by the probability of the actual fusion of nuclei (the so-called interaction cross section). In particular, the higher the kinetic energy of the nucleus and the lower its electric charge, the more likely it is to pass the electrostatic barrier and the faster the reaction rate (see graph). The key parameter of the theory of thermonuclear energy - the reaction ignition criterion - determines at what density and temperature of the plasma fuel the energy released during fusion (proportional to the reaction rate multiplied by the plasma density and burning time) will exceed the costs of plasma heating, taking into account losses and efficiency . The reaction of deuterium and tritium has the highest speed, and in order to achieve ignition, a plasma with a concentration of about 10 14 cm -3 must be heated to one and a half hundred million degrees and held for 1-2 seconds. In order to achieve a positive energy balance in reactions on other components - helium-3 or boron, the lower rate must be compensated by increasing the temperature and density of the plasma tenfold. But with a successful collision of two nuclei, energy is released, a thousand times greater than the energy spent on heating them. The initial reactions of the helium cycle, which form deuterium and tritium in the solar core, proceed so slowly that the corresponding curves do not fall into the field of this graph.

ill. 2. The solar wind is a stream of rarefied plasma constantly outflowing from solar surface into interplanetary space. The wind carries away only about 3x10 -14 solar masses per year, but it is this wind that turns out to be the main component of the interplanetary medium, displacing interstellar plasma from the vicinity of the Sun. This is how the heliosphere is created - a kind of bubble with a radius of about one hundred astronomical units, moving along with the Sun through interstellar gas. As astronomers hope, the American satellites Voyager 1 and Voyager 2 are now approaching its border, which will soon become the first spacecraft to leave the solar system. The solar wind was first discovered by the Soviet interplanetary station "Luna-2" in 1959, however, indirect evidence of the presence of a corpuscular stream coming from the Sun was known earlier. It is the solar wind that the inhabitants of the Earth owe magnetic storms(see "Science and Life" No. 7, 2001). At the orbit of the Earth, the wind contains on average only six ions per cubic centimeter, moving at a mind-boggling speed of 450 km / s, which, however, is not so fast by the scale of the solar system: it takes three days to travel to Earth. The solar wind is 96% protons and 4% helium nuclei. The admixture of other elements is insignificant.

ill. 3. Lunar regolith is a rather loose layer on the surface of the Moon several meters thick. It mainly consists of small fragments with an average size of less than a millimeter, accumulated over billions of years as a result of the destruction of lunar rocks during temperature changes and meteorite impacts. Studies of the lunar soil showed that the more titanium oxides in the regolith, the more helium atoms.

ill. 4. The presence of titanium in the near-surface layer is quite easily detected by remote spectroscopic analysis (red color in the right image of the figure obtained by the Clementine satellite), and thus a map of helium "deposits" is obtained, which, in general, coincide with the location of the lunar seas.

ill. 5. To extract one ton of helium-3, it is necessary to process the surface layer of regolith on an area of ​​at least 100 square kilometers. Along the way, it will be possible to obtain a significant amount of other gases that will be useful for arranging life on the moon. Pictures taken from the site

It has two protons and two neutrons.

Encyclopedic YouTube

1 / 5

✪ Helium - SUPERFLUID AND THE COLDEST ELEMENT!

✪ Superfluid helium. University of Stuttgart

✪ Prospects for thermonuclear energy (says physicist Anton Tyulusov)

✪ Operation "Helium"

✪ Operation "Helium". 3rd series

Subtitles

I want to recommend you the channel of Andrey of the degree on he shoots a video course on organic chemistry for grade 10, more than 40 videos on 12 topics are now available on his channel subscribe to andrey's channel to publish and play for 100 points, and so today I will tell you about the most common noble gas in the foreseeable universe, which, moreover, can also acquire unique superfluid properties at extremely low temperatures meet helium in periodic table this element is located in the upper right corner, it is very easy to find at number 2, I think that today people get acquainted with this inert gas since childhood, because due to its lightness relative to air, helium is great for inflating holiday balloons that children like so much, this is all because the fact that the molar mass of helium is about seven times less molar masses air, but still, in terms of prevalence, hels on earth are extremely rare in the air, it is only one part per million; the decay of uranium or thorium in the earth's crust, helium can accumulate in underground voids with natural gas and not escape into the atmosphere, however, if we take a larger scale, then in the entire observable universe or it will take an honorable second place in abundance among all elements, yielding only to hydrogen and forming about a quarter from all atoms, just imagine that all atoms are heavier than gel forms only two percent of the mass of the total mass of matter here you can feel how small we are on the scale of the universe, the main part of the case is in the composition of stars or in the atmosphere of gas giants in which, like in the whole the universe contains about 20 percent According to today's data, the main part of the gel located in space was formed during big bang about 14 billion years ago, let's now return from heaven to earth and consider the properties of this gas in a more tangible experiment. I have a small ampule with helium, which is at a very low pressure, about one hundredth of the atmospheric pressure, it can be seen that the gel has no color. it has no taste or smell, you could know if you ever tried to breathe this gas, however, such experiments are extremely dangerous since our cells do not breathe helium, they need oxygen for this, it even forced the current sellers of balloon gel balloons to add up to 20 percent to them oxygen that you hung at parties has become safer if a high-frequency discharge is passed through the oculus with gel high voltage then it will start glowing dimly orange the brightness of which will depend on the voltage and on the diameter of the ampoule I used as a voltage source for the generator dpla knew about and which gave me the opportunity to hold the ampoule right in my hand and for the presence of an electrical capacitance in my body, in principle, like any other, unlike it on or xenon, helium ignites already at a distance from the generator wire, since it has less ionization energy, unfortunately, from a chemical point of view, it does not really shine with interesting properties at all, it does not react with almost any substance, although in the form of a plasma it looks like what you see in a gel ampoule can form an extremely unstable compound with hydrogen, deuterium, or some metals, and at high pressures of thousands of atmospheres, special substances are even formed klart from and helios of nitrogen, which in the form of crystals can be grown on diamond substrates, it’s a pity that all these substances are very unstable and it’s almost impossible to see them at normal conditions but no need to upset After all, the gel has the most interesting and unique physical properties of all gases, the fact is that when cooled to a temperature of 42 kelvin, it actually becomes the lightest and also coldest liquid, the density of which is almost 10 times less than the density of water in degrees Celsius, liquid helium is obtained at crazy minus two hundred and sixty-eight degrees, which is very cold so cold that some metals at this temperature become superconductors, for example, mercury or niobium, in order to maintain such a low temperature, liquid helium is located in a double Dewar vessel, which is still cooled from the outside with liquid nitrogen. The same technology for cooling liquid helium is used in modern devices to create nuclear magnetic resonance in them superconductors connection niobium is cooled with liquid helium, which, due to its high cost, is in turn cooled with cheaper liquid nitrogen, thus the liquid gel serves medicine and also for research by scientists, but the most interesting thing is yet to come before that, I told you about the first form of liquid g helium, the so-called helium 1, if you start to cool it by lowering the pressure in the vessel, then liquid helium will eventually pass over the so-called linda. namely, it cools below a temperature of twice seventeen hundredths of a kelvin and becomes the second form of liquid helium, after this the boiling of the liquid stops instantly and liquid helium radically changes its properties at this temperature, heat-conducting liquid helium increases millions of times and becomes higher than that of copper or silver, therefore the liquid does not boils because heat is transferred instantly and evenly throughout the volume, in addition, when the lambda point is reached, helium becomes a superfluid liquid, that is, it loses absolutely all viscosity, namely, the resistance of one part of the liquid to movement relative to the other, there is an excellent experiment that proves this if poured into a small suspended cup over the current helium can then rise along the walls of the container in the form of a thin film and flow out of the cup, in addition, it easily passes through a layer of ceramics with a pore size of about one micron, and the lower the temperature of liquid helium, the easier this liquid passes through the barrier surprisingly also the fact that liquid helium in such a cooled form still has a viscosity that can be seen in 2 ways the transformation of the cylinder, the layers of the liquid still transfer rotation to the blades from above, as it can be, but here other quantum mechanisms already play a role whose behavior is fundamentally different from laws classical mechanics it’s like there is viscosity, but I don’t at the same time, that’s how it can be characterized in principle, and by the way, for the first time, the phenomena of superfluidity of liquid helium were discovered by the Soviet scientist Peter Kapitsa in 1938, and already in 1962, Lev Landau developed a theory of this effect, think that’s all, but here we are the topic of stars and space flights awaits again before that I told you about the most common isotope helium and helium 4 which has two protons and two neutrons however there is still an extremely rare isotope helium-3 which has two protons and one neutron the fact is that this isotope great for conducting thermonuclear fusion reactions with deuterium and in theory this process can help humanity abandon fossil fuels, but the problem is that on earth this isotope is incredibly rare because it immediately evaporates from the atmosphere, but on the moon where the atmosphere does not have this isotope much better preserved hypothetically, people could extract helium-3 from lunar regolith dust and use it to as a source of energy on earth, but so far it just seems like a fantasy on this topic, they even made an excellent film moon 2112, I recommend it for viewing, and in the end we can say that such a common sight helium gas has amazing properties at low temperatures, its properties are now used everywhere, for example, in medicine or for scientific research in which, for example, gaseous helium is used as a carrier gas in chromatography, but if you liked this video, do not forget to subscribe to the channel and click on the bell and put like to learn more new and interesting things in the future

Prevalence

Opening

The existence of helium-3 was suggested by the Australian scientist Mark Oliphant while working at the University of Cambridge at. This isotope was finally discovered by Luis Alvarez and Robert Kornog in .

Physical properties

Receipt

At present, helium-3 is not extracted from natural sources (insignificant amounts of helium-3 are available on Earth, which are extremely difficult to extract), but is created by the decay of artificially obtained tritium.

Price

The average price of helium-3 in 2009 was, according to some estimates, about 930 USD per liter.

Helium-3 mining plans on the Moon

Helium-3 is a by-product of reactions occurring on the Sun and is present in some quantity in the solar wind and the interplanetary medium. Helium-3 entering the Earth's atmosphere from interplanetary space quickly dissipates back, its concentration in the atmosphere is extremely low

Hypothetically, during thermonuclear fusion, when 1 ton of helium-3 reacts with 0.67 tons of deuterium, energy is released that is equivalent to the combustion of 15 million tons of oil (however, the technical feasibility of this reaction has not been studied at the moment). Consequently, the population of our planet of the lunar resource of helium-3 (according to the maximum estimates) could be enough for about five millennia. The main problem remains the reality of extracting helium from the lunar regolith. As mentioned above, the content of helium-3 in regolith is ~1 g per 100 tons. Therefore, to extract a ton of this isotope, at least 100 million tons of soil should be processed on site.

Usage

Neutron counters

Gas counters filled with helium-3 are used for neutron detection. This is the most common method for measuring the neutron flux. They react

n+ 3 He → 3 H + 1 H + 0.764 MeV.

The charged reaction products - triton and proton - are registered by a gas counter operating in the mode of a proportional counter or a Geiger-Muller counter.

Obtaining ultra-low temperatures

By dissolving liquid helium-3 in helium-4, millikelvin temperatures are reached.

The medicine

Helium-3 as nuclear fuel

The reaction 3 He + D → 4 He + p has a number of advantages over the most achievable deuterium-tritium reaction T + D → 4 He + n under terrestrial conditions. These benefits include:

1. Tens of times lower neutron flux from the reaction zone, which dramatically reduces the induced radioactivity and degradation of the reactor structural materials;
2. The resulting protons, unlike neutrons, are easily captured and can be used to generate additional electricity, for example, in an MHD generator;
3. Synthesis starting materials are inactive and their storage does not require special precautions;
4. In a reactor accident with depressurization of the core, the radioactivity of the release is close to zero.

The disadvantages of the helium-deuterium reaction include a significantly higher temperature threshold. It is necessary to reach a temperature of approximately 10 9 K due to the Coulomb barrier in order for it to start. And at a lower temperature, the thermonuclear reaction of fusion of deuterium nuclei with each other proceeds much more readily, and the reaction between deuterium and helium-3 does not occur.

In art

In science fiction works (games, films, anime), helium-3 sometimes acts as the main fuel and as a valuable resource, including that mined on the moon.

The plot of the 2009 British science fiction film Luna 2112 is based on the operation of the Lunar mining complex. The complex ensures the extraction of the helium-3 isotope, with the help of which it was possible to stop the catastrophic energy crisis on Earth.

In the political comedy Iron Sky, lunar helium-3 is the cause of an international nuclear conflict over mining rights.

In the anime " planetes» Helium-3 is used as fuel for rocket engines, etc.

Literature

• Dobbs E.R. Helium Three. - Oxford University press, 2000. ISBN 0-19-850640-6
• Galimov E.M. If you have energy, you can extract everything - Rare earths. 2014. No. 2. S. 6-12.
• The Helium-3 Shortage: Supply, Demand, and Options for Congress // FAS, December 22, 2010 (English)

Notes

1. Audi G., Wapstra A. H., Thibault C.

Probably few things in the field of thermonuclear energy are surrounded by myths like Helium 3. In the 80s-90s it was actively popularized as a fuel that would solve all the problems of controlled thermonuclear fusion, as well as one of the reasons to get out of the Earth (because on its earth is literally a few hundreds of kilograms, and on the moon a billion tons) and finally start developing solar system. All this is based on very strange ideas about the possibilities, problems and needs of thermonuclear energy that does not exist today, which we will talk about.

The machine for mining helium3 on the moon is already ready, the only thing left to do is to find a use for it.

When they talk about helium3, they mean thermonuclear fusion reactions He3 + D -> He4 + H or He3 + He3 -> 2He4 + 2H. Compared to classical D + T -> He4 +n there are no neutrons in the reaction products, which means that there is no activation of the construction of a thermonuclear reactor by superenergetic neutrons. In addition, the fact that neutrons from the “classics” carry away 80% of the energy from the plasma is considered a problem, so the self-heating balance occurs at a higher temperature. Another noteworthy advantage of the helium version is that electricity can be removed directly from the charged particles of the reaction, and not by heating water with neutrons - as in old coal-fired power plants.

So, all this is not true, or rather a very small part of the truth.

Let's start with the fact that at the same plasma density and optimal temperature, the reaction He3 + D will give in 40 times less energy release per cubic meter of working plasma. In this case, the temperature required for at least a 40-fold rupture will be 10 times higher - 100 keV (or one billion degrees) versus 10 for D +T. By itself, such a temperature is quite achievable (the current record for tokamaks is 50 keV, only two times worse), but in order to establish an energy balance (cooling rate VS heating rate, including self-heating), we need to increase the energy release by 50 times from cubic meters of He3 + D reaction, which can only be done by raising the density by the same 50 times. In combination with a tenfold increase in temperature, this gives increase in plasma pressure by 500 times- from 3-5 atm to 1500-2500 atm, and the same increase in back pressure to keep this plasma.

But the pictures are inspiring.

Remember, I wrote that the magnets of the ITER toroidal field, which create counterpressure to the plasma, are absolutely record-breaking products, the only ones in the world in terms of parameters? So, He3 fans suggest making magnets 500 times more powerful.

Ok, forget about the difficulties, maybe the advantages of this reaction pay them off?

Various thermonuclear reactions that are applicable for CTS. He3 + D gives slightly more energy than D + T, but a lot of energy is spent on overcoming the Coulomb repulsion (charge 3 and not 2), so the reaction is slow.

Let's start with neutrons. Neutrons in an industrial reactor will be serious problem, damage the body materials, heat all the elements facing the plasma so much that they have to be cooled with a decent flow of water. And most importantly, the activation of materials by neutrons will lead to the fact that even 10 years after the shutdown of a thermonuclear reactor, it will have thousands of tons of radioactive structures that cannot be disassembled by hand, and which will be aged in storage for hundreds and thousands of years. Getting rid of neutrons would obviously make it easier to create a thermonuclear power plant.

Fraction of energy carried away by neutrons. If you add more He3 to the reactor, you can reduce it to 1%, but this will further tighten the ignition conditions.

OK, but what about the direct conversion of the energy of charged particles into electricity? Experiments show that the flow of ions with an energy of 100 keV can be converted into electricity with 80% efficiency. We don't have neutrons here... I mean, they don't take away all the energy that we can only get in the form of heat - let's get rid of steam turbines and put in ion collectors?

Yes, there are technologies for direct conversion of plasma energy into electricity, they were actively studied in the 60s-70s, and showed an efficiency in the region of 50-60% (not 80, it should be noted). However, this idea is poorly applicable both in D + T reactors and in He3 + D. Why this is so, this picture helps to understand.

It shows the heat loss of the plasma through different channels. Compare D+T and D + He3. Transport is what can be used to directly convert plasma energy into electricity. If in the D + T variant, everything is taken away from us by nasty neutrons, then in the case of He3 + D, everything is taken away by the electromagnetic radiation of the plasma, mainly synchrotron and X-ray bremsstrahlung (in the picture Bremsstrahlung). The situation is almost symmetrical, all the same, it is necessary to remove heat from the walls and still by direct conversion we can't pull out more than 10-15% the energy of thermonuclear combustion, and the rest - the old fashioned way, through a steam engine.

Illustration in a study on direct plasma energy conversion at the largest open trap Gamma-10 in Japan.

In addition to theoretical limitations, there are also engineering ones - in the world (including in the USSR) gigantic efforts were spent on creating installations for the direct conversion of plasma energy into electricity for conventional power plants, which made it possible to increase the efficiency from 35% to 55%. Mainly based on MHD generators. 30 years of work of large teams ended in zilch - the resource of the installation was hundreds of hours, when power engineers need thousands and tens of thousands. The gigantic amount of resources spent on this technology has led, in particular, to the fact that our country has lagged behind in the production of power gas turbines and steam-gas turbine cycle plants (which give exactly the same increase in efficiency - from 35 to 55%!).

By the way, powerful superconducting magnets are also needed for MHD generators. Shown here are the SP magnets for a 30 MW MHD generator.