A thermonuclear reactor has been created. Iter - international thermonuclear reactor (iter)

Thermonuclear power plant.

Currently, scientists are working on the creation of a thermonuclear power plant, the advantage of which is to provide humanity with electricity for an unlimited time. A thermonuclear power plant operates on the basis of thermonuclear fusion— fusion reactions of heavy hydrogen isotopes with the formation of helium and the release of energy. The fusion reaction does not produce gaseous and liquid radioactive waste, nor does it produce plutonium, which is used to make nuclear weapons. If we also take into account that the fuel for thermonuclear stations will be the heavy hydrogen isotope deuterium, which is obtained from plain water - half a liter of water contains fusion energy equivalent to that obtained by burning a barrel of gasoline - then the advantages of power plants based on thermonuclear reaction, become obvious.

During a thermonuclear reaction, energy is released when light atoms combine and turn them into heavier ones. To achieve this, it is necessary to heat the gas to a temperature of over 100 million degrees - much higher than the temperature at the center of the Sun.

Gas at this temperature turns into plasma. At the same time, hydrogen isotope atoms merge, turning into helium atoms and neutrons and releasing a large amount of energy. A commercial power plant operating on this principle would use the energy of neutrons moderated by a layer of dense matter (lithium).

Compared to a nuclear power plant, a fusion reactor will leave behind much less radioactive waste.

International thermonuclear reactor ITER

Members of the international consortium to create the world's first thermal nuclear reactor ITER signed an agreement in Brussels that launches the practical implementation of the project.

Representatives of the European Union, USA, Japan, China, South Korea and Russia intend to start construction of an experimental reactor in 2007 and complete it within eight years. If everything goes according to plan, by 2040 a demonstration power plant operating on the new principle could be built.

I would like to believe that the era of environmentally hazardous hydroelectric power plants and nuclear power plants will soon end, and the time will come for a new power plant - a thermonuclear one, the project of which is already underway. But, despite the fact that the ITER project (International Thermonuclear Reactor) is almost ready; despite the fact that already at the first operating experimental thermonuclear reactors a power exceeding 10 MW, the level of the first nuclear power plants, was obtained, the first thermonuclear power plant will start operating no earlier than in twenty years, because its cost is very high. The cost of the work is estimated at 10 billion euros - this is the most expensive international power plant project. Half of the cost of building the reactor is covered by the European Union. Other members of the consortium will allocate 10% of the budget.

Now the plan for the construction of the reactor, which will become the most expensive joint scientific project after, must be ratified by the parliamentarians of the countries participating in the consortium.

The reactor will be built in the southern French province of Provence, in the vicinity of the city of Cadarache, where the French nuclear research center is located.

ITER - International Thermonuclear Reactor (ITER)

Energy consumption by mankind is growing every year, which pushes the energy sector to active development. So with the advent of nuclear power plants, the amount of energy generated around the world has increased significantly, which made it possible to safely use energy for all the needs of mankind. For example, 72.3% of the electricity generated in France comes from nuclear power plants, in Ukraine - 52.3%, in Sweden - 40.0%, in the UK - 20.4%, in Russia - 17.1%. However, technology does not stand still, and in order to cater to the further energy needs of the countries of the future, scientists are working on a number of innovative projects, one of which is ITER - International Thermonuclear Experimental Reactor (ITER, International Thermonuclear Experimental Reactor).

Although the profitability of this facility is still in question, according to the work of many researchers, the creation and subsequent development of controlled thermonuclear fusion technology can result in a powerful and safe source of energy. Consider some of the positive aspects of such an installation:

• The main fuel of a thermonuclear reactor is hydrogen, which means practically inexhaustible reserves of nuclear fuel.
• Hydrogen production can occur through processing sea ​​water which is available in most countries. This implies the impossibility of the emergence of a monopoly of fuel resources.
• The probability of an accidental explosion during the operation of a thermonuclear reactor is much less than during the operation of a nuclear reactor. According to researchers, even in the event of an accident, radiation emissions will not pose a danger to the population, which means there is no need for evacuation.
• Unlike nuclear reactors, fusion reactors produce radioactive waste that has a short half-life, meaning it decays faster. Also in thermonuclear reactors there are no products of combustion.
• The operation of a fusion reactor does not require materials that are also used for nuclear weapons. This makes it possible to exclude the possibility of covering up the production of nuclear weapons by processing materials for the needs of a nuclear reactor.

Fusion reactor - inside view

However, there are also a number of technical shortcomings that researchers constantly encounter.

For example, the current version of the fuel, presented in the form of a mixture of deuterium and tritium, requires the development of new technologies. For example, at the end of the first series of tests at the JET, the largest fusion reactor to date, the reactor became so radioactive that further development of a special robotic maintenance system was required to complete the experiment. Another disappointing factor in the operation of a thermonuclear reactor is its efficiency - 20%, while the efficiency of nuclear power plants is 33-34%, and thermal power plants - 40%.

Creation of the ITER project and launch of the reactor

The ITER project started in 1985 when Soviet Union proposed the joint creation of a tokamak - a toroidal chamber with magnetic coils, which is capable of holding the plasma with the help of magnets, thereby creating the conditions required for the fusion reaction to proceed. In 1992, a quadripartite agreement on the development of ITER was signed, the parties to which were the EU, USA, Russia and Japan. The Republic of Kazakhstan joined the project in 1994, Canada in 2001, South Korea and China in 2003, and India in 2005. In 2005, the site for the construction of the reactor was determined - the research center for nuclear energy Cadarache, France.

The construction of the reactor began with the preparation of a foundation pit. So the parameters of the pit were 130 x 90 x 17 meters. The entire complex with the tokamak will weigh 360,000 tons, of which 23,000 tons will be the tokamak itself.

Various elements of the ITER complex will be developed and delivered to the construction site from all over the world. So in 2016, part of the conductors for poloidal coils was developed in Russia, which then went to China, which will produce the coils themselves.

Obviously, such a large-scale work is not at all easy to organize, a number of countries have repeatedly failed to keep up with the set project schedule, as a result of which the launch of the reactor has been constantly postponed. So, according to last year's (2016) June message: "obtaining the first plasma is scheduled for December 2025."

The mechanism of operation of the ITER tokamak

The term "tokamak" comes from a Russian acronym which means "toroidal chamber with magnetic coils".

The heart of the tokamak is its torus-shaped vacuum chamber. Inside, under the influence of extreme temperature and pressure, gaseous hydrogen fuel becomes a plasma - a hot electrically charged gas. As is known, stellar matter is represented by plasma, and thermonuclear reactions in the core of the Sun occur precisely under conditions of elevated temperature and pressure. Similar conditions for the formation, retention, compression and heating of the plasma are created by means of massive magnetic coils, which are located around the vacuum vessel. The impact of magnets will limit the hot plasma from the walls of the vessel.

Before starting the process, air and impurities are removed from vacuum chamber. Magnetic systems are then charged to help control the plasma, and gaseous fuel is injected. When a powerful electric current passes through the vessel, the gas is electrically split and becomes ionized (that is, the electrons leave the atoms) and forms a plasma.

As the plasma particles are activated and collide, they also begin to heat up. Auxiliary heating techniques help bring the plasma to melting temperatures (150 to 300 million °C). Particles "excited" to this extent can overcome their natural electromagnetic repulsion when colliding, and as a result of such collisions, a huge amount of energy is released.

The design of the tokamak consists of the following elements:

vacuum vessel

("donut") - a toroidal chamber made of of stainless steel. Its large diameter is 19 m, small - 6 m, and height - 11 m. The volume of the chamber is 1,400 m 3, and its mass is more than 5,000 tons. water. In order to avoid water contamination, the inner wall of the chamber is protected from radioactive radiation by means of a blanket.

Blanket

("blanket") - consists of 440 fragments covering the inner surface of the chamber. The total area of ​​the banquet is 700m 2 . Each fragment is a kind of cassette, the body of which is made of copper, and the front wall is removable and made of beryllium. The parameters of the cassettes are 1x1.5 m, and the mass is no more than 4.6 tons. Such beryllium cassettes will slow down the high-energy neutrons produced during the reaction. During neutron moderation, heat will be released, which is removed by the cooling system. It should be noted that the beryllium dust generated as a result of the operation of the reactor can cause a serious disease called berylliosis, and also has a carcinogenic effect. For this reason, strict security measures are being developed in the complex.

Tokamak in section. Yellow - solenoid, orange - toroidal field (TF) and poloidal field (PF) magnets, blue - blanket, light blue - VV - vacuum vessel, purple - divertor

(“ashtray”) of a poloidal type is a device whose main task is to “cleanse” the plasma from dirt resulting from the heating and interaction of the chamber walls covered with a blanket with it. When such contaminants enter the plasma, they begin to radiate intensely, as a result of which additional radiation losses occur. It is located in the lower part of the tokomak and with the help of magnets directs the upper layers of the plasma (which are the most contaminated) into the cooling chamber. Here, the plasma cools and turns into a gas, after which it is pumped back out of the chamber. Beryllium dust, after entering the chamber, is practically unable to return back to the plasma. Thus, plasma contamination remains only on the surface and does not penetrate deep into.

Cryostat

- the largest component of the tokomak, which is a stainless steel shell with a volume of 16,000 m 2 (29.3 x 28.6 m) and a mass of 3,850 tons. Other elements of the system will be located inside the cryostat, and it itself will serve as a barrier between the tokamak and external environment. On its inner walls there will be heat shields cooled by circulating nitrogen at a temperature of 80 K (-193.15 °C).

Magnetic system

- a complex of elements that serve to contain and control the plasma inside the vacuum vessel. It is a set of 48 elements:

• Toroidal field coils are located outside the vacuum chamber and inside the cryostat. Presented in the amount of 18 pieces, each of which is 15 x 9 m in size and weighs approximately 300 tons. Together, these coils generate a magnetic field of 11.8 T around the plasma torus and store energy of 41 GJ.
• Poloidal field coils - located on top of the toroidal field coils and inside the cryostat. These coils are responsible for the formation of a magnetic field that separates the plasma mass from the chamber walls and compresses the plasma for adiabatic heating. The number of such coils is 6. Two of the coils have a diameter of 24 m and a mass of 400 tons. The remaining four are somewhat smaller.
• The central solenoid is located in the inside of the toroidal chamber, or rather in the “donut hole”. The principle of its operation is similar to a transformer, and the main task is to excite the inductive current in the plasma.
• Correction coils are located inside the vacuum vessel, between the blanket and the chamber wall. Their task is to preserve the shape of the plasma, capable of locally "bulging" and even touching the walls of the vessel. Allows to reduce the level of interaction of the chamber walls with the plasma, and hence the level of its contamination, and also reduces the wear of the chamber itself.

Structure of the ITER complex

The above-described "in a nutshell" design of the tokamak is a complex innovative mechanism, assembled by the efforts of several countries. However, for its full-fledged operation, a whole complex of buildings located near the tokamak is required. Among them:

• Control, Data Access and Communication System - CODAC. It is located in a number of buildings of the ITER complex.
• Fuel storage and fuel system - serves to deliver fuel to the tokamak.
• Vacuum system - consists of more than four hundred vacuum pumps, whose task is to pump out the products of a thermonuclear reaction, as well as various contaminants from the vacuum chamber.
• Cryogenic system - represented by a nitrogen and helium circuit. The helium circuit will normalize the temperature in the tokamak, the work (and hence the temperature) of which does not proceed continuously, but in impulses. The nitrogen circuit will cool the thermal screens of the cryostat and the helium circuit itself. There will also be water system cooling, which is aimed at lowering the temperature of the blanket walls.
• Power supply. The tokamak will require approximately 110 MW of power to operate continuously. For this, power lines per kilometer will be laid, which will be connected to the French industrial network. It is worth recalling that the ITER experimental facility does not provide for energy generation, but works only in scientific interests.

ITER financing

The international thermonuclear reactor ITER is a rather expensive undertaking, which was originally estimated at 12 billion dollars, where Russia, the USA, Korea, China and India account for 1/11 of the amount, Japan - 2/11, and the EU - 4/11 . Later this amount increased to 15 billion dollars. It is noteworthy that financing occurs through the supply of equipment required for the complex, which is developed in each of the countries. Thus, Russia supplies blankets, plasma heating devices and superconducting magnets.

Project perspective

AT this moment the construction of the ITER complex and the production of all the required components for the tokamak. After the planned launch of the tokamak in 2025, a series of experiments will begin, based on the results of which aspects that need improvement will be noted. After the successful commissioning of ITER, it is planned to build a power plant based on thermonuclear fusion called DEMO (DEMOnstration Power Plant). DEMo's mission is to demonstrate the so-called "commercial appeal" of fusion energy. If ITER is capable of generating only 500 MW of energy, then DEMO will allow continuous generation of 2 GW of energy.

However, it should be borne in mind that the ITER experimental facility will not generate energy, and its purpose is to obtain a purely scientific benefit. And as you know, this or that physical experiment can not only justify expectations, but also bring new knowledge and experience to mankind.

10:14 a.m. - International Experimental Thermonuclear Reactor ITER

The construction site of the ITER fusion reactor in October 2016. The reactor itself will be there in the center, where the circle with the crane is.

So, this is the first post with a record and a short description of what we discussed in my rubric on Silver rain. The topic of yesterday's issue was thermonuclear energy and the most expensive scientific installation in the world - ITER.

So what is ITER?
ITER (International Thermonuclear Experimental Reactor) is an international experimental thermonuclear reactor. It is being built by the efforts of dozens of countries in the French nuclear center Cadarache. Planning for it began back in the 1980s, the project was developed from 1992 to 2007, construction began in 2009. The first plasma is expected to be received in 2025, and the final completion and reaching the maximum planned work parameters according to the project will be around 2035. Why is this important and interesting? First, ITER is the most expensive and complex scientific and experimental facility in the world. Its cost is already estimated at more than 20 billion euros. The Large Hadron Collider, for comparison, cost 6 billion euros and took 7 years to build. Secondly, ITER is the most important thing that is being done now towards the development of thermonuclear energy, which can potentially solve all the energy problems of mankind in the future. The task of the installation is to demonstrate the possibility of controlled thermonuclear fusion with the power industrial scale and accumulation of experience for the construction of the first thermonuclear power plant. So ITER itself will not generate electricity yet.

In a thermonuclear reactor, unlike a conventional nuclear reactor, it is not the fission reaction of heavy nuclei of uranium or plutonium that is used, but the reaction of the synthesis of light helium nuclei from hydrogen isotopes - deuterium and tritium. A similar fusion reaction takes place in the Sun, so the "alternative" solar and wind energy is in some way an indirect use of the thermonuclear energy of our star.

At the same time, it is very difficult to create a controlled thermonuclear fusion reaction. They learned how to produce an uncontrolled thermonuclear reaction on earth - in the form of hydrogen thermonuclear bombs, the most powerful of those created by man. But for peaceful purposes it cannot be used yet. There are several difficulties here. First, the fusion reaction requires a high temperature. It is necessary to disperse and collide two light nuclei with the same positive charge, which at lower speeds will simply repel. Therefore, the temperature of the Sun reaches 15 million degrees, and in the ITER reactor there will be even more - 150 million degrees.

Substance at such a temperature exists only in the form of plasma - the fourth aggregate state of matter after solid, liquid and gaseous, where there are no longer atoms, but only separate charged particles - nuclei, protons and electrons. Therefore, the second difficulty of a thermonuclear installation is the retention of this plasma inside the reactor. No material can withstand contact with this plasma, so it will have to be held not by matter, but by a magnetic field. If you give the field a closed shape, then the charged particles will be inside it. However, it is even theoretically impossible to create a spherical closed magnetic field (due to the hedgehog combing theorem), so a torus-shaped field was proposed to contain the plasma. Bagel, in other words. And it was invented and implemented for the first time by Soviet scientists. Therefore, the name of such a design - Tokamak (Toroidal chamber with magnetic coils), entered the world of science from the Russian language. ITER will be the largest and most powerful tokamak in the world, although there are already more than 300 of them on the planet.

Well, and one more difficulty - to create the necessary magnetic field, huge superconducting magnets are needed, cooled by liquid helium to temperatures below -270 degrees Celsius. So it turns out that a tokamak is a device where, in a complete vacuum (because apart from fuel, deuterium and tritium, no gas impurities are allowed inside) inside the coils with sub-zero temperature the reaction will take place at a temperature of 150 million degrees. This is the hot sandwich. More specifically, a bagel.

The size and complexity of the installation can be estimated from this diagram.

But what is the actual size of those magnet rings from which the tokamak chamber shown in the diagram above will be assembled. More exciting photos.

Read more about the physics of the tokamak and its device on the fingers here.

It would be difficult for even the most developed countries to pull off such a project alone. Due to the complexity of the installation, it was necessary to combine the knowledge and experience of all countries involved in fusion research. The ITER project involves the united European Union, the USA, Russia, Japan, South Korea, China, and India. Later, Kazakhstan joined it, and recently even Iran. Someone invests in the project with money, and someone in the form of building equipment. Russia, for example, builds many important components, as shown in the picture below. And you can read more about Russia's participation on the website of the Russian project center ITER.

Parts of the ITER design, which are made in Russia. Their value is several billion euros.

Combining efforts is beneficial for everyone - by investing their part, countries then get access to all the information obtained at the pilot facility. Thermonuclear energy can indeed become the property of all mankind. Another possible reason for the project being implemented as an international cooperation is risk sharing. It is still very far from the appearance of commercial installations (ITER itself will not even generate energy yet, after it the next DEMO reactor will do it), everyone understands this, and it is unprofitable to pull such an expensive experiment alone. Countries, roughly speaking, invest in the distant future and maintain the scientific potential in the field of thermonuclear energy, but at the same time they share the risks that the product will not appear soon and not in the form in which it can be used.

Although I was engaged in the study of nuclear energy, but a thermonuclear reactor is a topic so separate and far from traditional nuclear power plants that only now I have plunged deep enough into it. Now it seems to me that technically the problem of peaceful use of controlled thermonuclear energy will be solved. That's just how much it will be in demand by the time of creation and when exactly this will happen is still difficult to say.

How it all started. The “energy challenge” arose as a result of a combination of the following three factors:

1. Humanity now consumes a huge amount of energy.

The world's current energy consumption is about 15.7 terawatts (TW). Dividing this value by the population of the planet, we get about 2400 watts per person, which can be easily estimated and imagined. The energy consumed by every inhabitant of the Earth (including children) corresponds to the round-the-clock operation of 24 hundred-watt electric lamps. However, the consumption of this energy around the planet is very uneven, as it is very high in several countries and negligible in others. Consumption (in terms of one person) is 10.3 kW in the USA (one of the record values), 6.3 kW in Russian Federation, 5.1 kW in the UK, etc., but on the other hand, it is only 0.21 kW in Bangladesh (only 2% of the US consumption!).

2. World energy consumption is increasing dramatically.

According to the forecast of the International Energy Agency (2006), world energy consumption should increase by 50% by 2030. Developed countries, of course, could do just fine without additional energy, but this growth is necessary to lift the population of developing countries, where 1.5 billion people are suffering from an acute shortage of electrical energy, out of poverty.

3. Currently, 80% of the world's energy is generated by burning fossil fuels(oil, coal and gas), the use of which:

a) potentially carries the risk of catastrophic environmental changes;

b) must inevitably end someday.

From what has been said, it is clear that already now we must prepare for the end of the era of the use of fossil fuels.

At present, nuclear power plants receive on a large scale the energy released during the fission reactions of atomic nuclei. The creation and development of such stations should be encouraged in every possible way, but it should be taken into account that the reserves of one of the most important material for their operation (cheap uranium) can also be completely used up over the next 50 years. The possibilities of nuclear fission-based energy can (and should) be significantly expanded through the use of more efficient energy cycles, which can almost double the amount of energy produced. For the development of energy in this direction, it is necessary to create reactors on thorium (the so-called thorium breeder reactors or breeder reactors), in which more thorium is produced during the reaction than the original uranium, as a result of which the total amount of energy received for a given amount of substance increases by 40 times . It also seems promising to create fast-neutron plutonium breeders, which are much more efficient than uranium reactors and make it possible to obtain 60 times more energy. Perhaps, for the development of these areas, it will be necessary to develop new, non-standard methods for obtaining uranium (for example, from sea water, which seems to be the most accessible).

Fusion power plants

The figure shows a schematic diagram (not to scale) of the device and the principle of operation of a thermonuclear power plant. In the central part, there is a toroidal (donut-shaped) chamber with a volume of ~2000 m3 filled with tritium-deuterium (T–D) plasma heated to a temperature above 100 M°C. The neutrons produced during the fusion reaction (1) leave the "magnetic bottle" and fall into the shell shown in the figure with a thickness of about 1 m.

Inside the shell, neutrons collide with lithium atoms, resulting in a reaction with the formation of tritium:

neutron + lithium → helium + tritium

In addition, competing reactions occur in the system (without the formation of tritium), as well as many reactions with the release of additional neutrons, which then also lead to the formation of tritium (in this case, the release of additional neutrons can be significantly enhanced, for example, by introducing beryllium atoms into the shell and lead). The general conclusion is that this facility could (at least theoretically) be a nuclear fusion reaction that would produce tritium. In this case, the amount of tritium formed should not only meet the needs of the installation itself, but even be somewhat larger, which will make it possible to provide new installations with tritium. It is this operating concept that must be tested and implemented in the ITER reactor described below.

In addition, the neutrons must heat the shell in the so-called pilot plants (which will use relatively "ordinary" structural materials) to a temperature of approximately 400°C. In the future, it is planned to create improved installations with a shell heating temperature above 1000°C, which can be achieved through the use of the latest high-strength materials (such as silicon carbide composites). The heat released in the shell, as in conventional stations, is taken by the primary cooling circuit with a coolant (containing, for example, water or helium) and transferred to the secondary circuit, where water vapor is produced and supplied to the turbines.

1985 - The Soviet Union proposed the next generation Tokamak plant, using the experience of four leading countries to create thermonuclear reactors. The United States of America, together with Japan and the European Community, put forward a proposal for the implementation of the project.

France is currently building the International Tokamak Experimental Reactor (ITER), described below, which will be the first tokamak capable of "igniting" plasma.

The most advanced tokamak-type facilities in existence have long reached temperatures of the order of 150 M°C, close to those required for the operation of a fusion plant, but the ITER reactor should be the first large-scale power plant designed for long-term operation. In the future, it will be necessary to significantly improve the parameters of its operation, which will require, first of all, an increase in the pressure in the plasma, since the rate of nuclear fusion at a given temperature is proportional to the square of the pressure. The main scientific problem in this case is related to the fact that when the pressure in the plasma increases, very complex and dangerous instabilities arise, that is, unstable modes of operation.

Why do we need it?

The main advantage of nuclear fusion is that it requires only a very small amount of naturally occurring substances as fuel. The nuclear fusion reaction in the described facilities can lead to the release huge amount energy, ten million times higher than the standard heat release from conventional chemical reactions(such as burning fossil fuels). For comparison, we point out that the amount of coal required to operate a thermal power plant with a capacity of 1 gigawatt (GW) is 10,000 tons per day (ten railway cars), and a fusion plant of the same capacity will consume only about 1 kilogram of a D + T mixture per day. .

Deuterium is a stable isotope of hydrogen; in about one out of every 3350 molecules of ordinary water, one of the hydrogen atoms is replaced by deuterium (a legacy inherited from the Big Bang). This fact makes it easy to organize a fairly cheap production of the required amount of deuterium from water. It is more difficult to obtain tritium, which is unstable (half-life is about 12 years, as a result of which its content in nature is negligible), however, as shown above, tritium will arise directly inside the fusion plant during operation, due to the reaction of neutrons with lithium.

Thus, the initial fuel for a thermonuclear reactor is lithium and water. Lithium is a common metal widely used in household appliances(in batteries for mobile phones etc.). The plant described above, even with imperfect efficiency, will be able to produce 200,000 kWh of electrical energy, which is equivalent to the energy contained in 70 tons of coal. The amount of lithium required for this is contained in one computer battery, and the amount of deuterium is contained in 45 liters of water. The above value corresponds to the current consumption of electricity (in terms of one person) in the EU countries for 30 years. The very fact that such an insignificant amount of lithium can provide the generation of such an amount of electricity (without CO2 emissions and without the slightest pollution of the atmosphere) is a sufficiently serious argument for the rapid and vigorous development of thermonuclear energy (despite all the difficulties and problems) and even without one hundred percent certainty in the success of such research.

Deuterium should last for millions of years, and easily mined lithium reserves are quite sufficient to meet the needs for hundreds of years. Even if lithium reserves in rocks runs out, we can extract it from the water, where it is found in a concentration high enough (100 times that of uranium) to make it economically viable to mine.

An experimental thermonuclear reactor (International thermonuclear experimental reactor) is being built near the city of Cadarache in France. The main task of the ITER project is the implementation of a controlled thermonuclear fusion reaction on an industrial scale.

Per unit weight of thermonuclear fuel, about 10 million times more energy is obtained than by burning the same amount of organic fuel, and about a hundred times more than by fissioning uranium nuclei in the reactors of currently operating nuclear power plants. If the calculations of scientists and designers are justified, this will give humanity an inexhaustible source of energy.

Therefore, a number of countries (Russia, India, China, Korea, Kazakhstan, USA, Canada, Japan, EU countries) joined their efforts in creating the International Thermonuclear Research Reactor - a prototype of new power plants.

ITER is an installation that creates conditions for the synthesis of hydrogen atoms and tritium (an isotope of hydrogen), resulting in the formation of a new atom - a helium atom. This process is accompanied by a huge surge of energy: the temperature of the plasma in which the thermonuclear reaction takes place is about 150 million degrees Celsius (for comparison, the temperature of the core of the Sun is 40 million degrees). In this case, the isotopes burn out, leaving practically no radioactive waste.

Participation scheme in international project provides for the supply of reactor components and financing of its construction. In exchange for this, each of the participating countries receives full access to all technologies for creating a thermonuclear reactor and to the results of all experimental work on this reactor, which will serve as the basis for the design of serial power thermonuclear reactors.

The reactor, based on the principle of thermonuclear fusion, has no radioactive radiation and is completely safe for environment. It can be located almost anywhere the globe, and ordinary water serves as fuel for it. Construction of ITER should take about ten years, after which the reactor is supposed to be used for 20 years.

Russia's interests in the Council of the International Organization for the Construction of the ITER Thermonuclear Reactor in the coming years will be represented by Corresponding Member of the Russian Academy of Sciences Mikhail Kovalchuk - Director of the Kurchatov Institute, the Institute of Crystallography of the Russian Academy of Sciences and Scientific Secretary of the Presidential Council for Science, Technology and Education. Kovalchuk will temporarily replace Academician Yevgeny Velikhov in this post, who has been elected Chairman of the International Council of ITER for the next two years and does not have the right to combine this position with the duties of an official representative of a participating country.

The total cost of construction is estimated at 5 billion euros, and the same amount will be required for the trial operation of the reactor. The shares of India, China, Korea, Russia, the US and Japan each account for approximately 10 percent of the total value, with 45 percent accounted for by the countries of the European Union. However, while the European states have not agreed how exactly the costs will be distributed among them. Because of this, the start of construction was postponed to April 2010. Despite another delay, scientists and officials involved in the creation of ITER say they will be able to complete the project by 2018.

The estimated thermonuclear power of ITER is 500 megawatts. Individual parts of the magnets reach a weight of 200 to 450 tons. To cool ITER, 33,000 cubic meters of water per day will be required.

In 1998, the US stopped funding its participation in the project. After the Republicans came to power in the country, and rolling blackouts began in California, the Bush administration announced an increase in energy investments. The United States did not intend to participate in the international project and was engaged in its own thermonuclear project. In early 2002, President Bush's technology adviser John Marburger III announced that the US had changed its mind and intended to return to the project.

In terms of the number of participants, the project is comparable to another major international scientific project - the International space station. The cost of ITER, which previously reached 8 billion dollars, then amounted to less than 4 billion. As a result of the withdrawal of the United States, it was decided to reduce the reactor power from 1.5 GW to 500 MW. Accordingly, the price of the project “lost weight”.

In June 2002, the symposium "ITER Days in Moscow" was held in the Russian capital. It discussed the theoretical, practical and organizational problems of the revival of the project, the success of which can change the fate of mankind and give it a new type of energy, in terms of efficiency and economy comparable only to solar energy.

In July 2010, representatives of the countries participating in the project of the international thermonuclear reactor ITER approved its budget and construction time at an extraordinary meeting held in Cadarache, France. The meeting report is available here.

At the last extraordinary meeting, the project participants approved the date for the start of the first experiments with plasma - 2019. Full trials are planned for March 2027, although project management has asked technical staff to try to optimize the process and start trials in 2026. The participants of the meeting also decided on the costs for the construction of the reactor, however, the amounts planned to be spent on the creation of the facility were not disclosed. According to information received by the editor of the ScienceNOW portal from an unnamed source, by the time the experiments begin, the cost of the ITER project may be 16 billion euros.

The meeting in Cadarache was also the first official working day for the project's new director, Japanese physicist Osamu Motojima. Before him, the project was led by the Japanese Kaname Ikeda since 2005, who wished to leave the post immediately after the approval of the budget and construction time.

The ITER fusion reactor is a joint project of the European Union, Switzerland, Japan, the USA, Russia, South Korea, China and India. The idea of ​​creating ITER has been considered since the 80s of the last century, however, due to financial and technical difficulties, the cost of the project is constantly growing, and the start date of construction is constantly being postponed. In 2009, experts expected that work on the creation of the reactor would begin in 2010. Later, this date was moved, and first 2018 and then 2019 were called as the launch time of the reactor.

Fusion reactions are fusion reactions of nuclei of light isotopes with the formation of a heavier nucleus, which are accompanied by a huge release of energy. In theory, fusion reactors can produce a lot of energy at low cost, but currently scientists are spending a lot more energy and money to start and maintain a fusion reaction.

Fusion is a cheap and environmentally friendly way to produce energy. For billions of years, uncontrolled thermonuclear fusion has been taking place on the Sun - helium is formed from the heavy isotope of hydrogen deuterium. This releases an enormous amount of energy. However, people on Earth have not yet learned to control such reactions.

Hydrogen isotopes will be used as fuel in the ITER reactor. During a thermonuclear reaction, energy is released when light atoms combine to form heavier ones. To achieve this, it is necessary to heat the gas to a temperature of over 100 million degrees - much higher than the temperature at the center of the Sun. Gas at this temperature turns into plasma. At the same time, hydrogen isotope atoms merge, turning into helium atoms with the release a large number neutrons. A power plant operating on this principle will use the energy of neutrons moderated by a layer of dense matter (lithium).

Why did the creation of thermonuclear installations take so long?

Why is it that such important and valuable installations, the advantages of which have been discussed for almost half a century, have not yet been created? There are three main reasons (discussed below), the first of which can be called external or public, and the other two - internal, that is, due to the laws and conditions for the development of thermonuclear energy itself.

1. For a long time, it was believed that the problem of the practical use of fusion energy does not require urgent decisions and actions, since back in the 80s of the last century, fossil fuel sources seemed inexhaustible, and environmental problems and climate change did not concern the public. In 1976, the Fusion Energy Advisory Committee at the US Department of Energy attempted to estimate the timing of R&D and the construction of a demonstration fusion power plant at different options research funding. At the same time, it turned out that the volume of annual funding for research in this direction is completely insufficient, and while maintaining the existing level of appropriations, the creation of thermonuclear installations will never be successful, since the allocated funds do not even correspond to the minimum, critical level.

2. A more serious obstacle to the development of research in this area is that a thermonuclear facility of the type under discussion cannot be created and demonstrated on a small scale. From the explanations presented below, it will become clear that thermonuclear fusion requires not only the magnetic confinement of the plasma, but also its sufficient heating. The ratio of energy expended and received increases at least in proportion to the square of the linear dimensions of the installation, as a result of which the scientific and technical capabilities and advantages of thermonuclear installations can be tested and demonstrated only at fairly large stations, such as the ITER reactor mentioned above. The society was simply not ready to finance such large projects until there was sufficient confidence in success.

3. The development of thermonuclear energy was of a very complex nature, however (despite insufficient funding and difficulties in choosing centers for the creation of JET and ITER facilities) in last years clear progress is being made, although an operating station has yet to be established.

The modern world is facing a very serious energy challenge, which can more accurately be called an "uncertain energy crisis". The problem is related to the fact that the reserves of fossil fuels may run out in the second half of this century. Moreover, the burning of fossil fuels may lead to the need to somehow capture and "store" the carbon dioxide released into the atmosphere (the CCS program mentioned above) in order to prevent serious changes in the planet's climate.

At present, almost all the energy consumed by mankind is created by burning fossil fuels, and the solution to the problem may be associated with the use of solar energy or nuclear energy (creation of fast breeder reactors, etc.). The global problem caused by the growing population of developing countries and their need to improve living standards and increase the amount of energy produced cannot be solved only on the basis of the approaches considered, although, of course, any attempts to develop alternative methods of energy generation should be encouraged.

As a matter of fact, we have a small choice of behavioral strategies and the development of thermonuclear energy is extremely important, even though there is no guarantee of success. The Financial Times (dated January 25, 2004) wrote about this:

“Even if the cost of the ITER project significantly exceeds the original estimate, it is unlikely that they will reach the level of 1 billion dollars a year. This level of cost should be considered a very modest price to pay for a very reasonable opportunity to create a new source of energy for all mankind, especially considering that already in this century we will inevitably have to break the habit of wasteful and reckless burning of fossil fuels.

Let's hope that there will be no major and unexpected surprises in the way of the development of thermonuclear energy. In this case, in about 30 years, we will be able to supply electric current from it to the energy networks for the first time, and in a little more than 10 years, the first commercial thermonuclear power plant will begin to operate. It is possible that in the second half of our century, nuclear fusion energy will begin to replace fossil fuels and gradually begin to play an increasingly important role in providing humanity with energy on a global scale.

There is no absolute guarantee that the task of creating thermonuclear energy (as an efficient and large-scale source of energy for all mankind) will be completed successfully, but the probability of success in this direction is quite high. Considering the huge potential of thermonuclear power plants, all the costs for projects of their rapid (and even accelerated) development can be considered justified, especially since these investments look very modest against the backdrop of a monstrous world energy market (4 trillion dollars a year8). Meeting the needs of mankind in energy is a very serious problem. As fossil fuels become less and less available (in addition, their use becomes undesirable), the situation is changing, and we simply cannot afford not to develop fusion power.

To the question "When will thermonuclear energy appear?" Lev Artsimovich (a recognized pioneer and leader of research in this area) once replied that "it will be created when it becomes really necessary for mankind"

ITER will be the first fusion reactor to generate more energy than it consumes. Scientists measure this characteristic with a simple factor they call "Q". If ITER makes it possible to achieve all the set scientific goals, then it will produce 10 times more energy than it consumes. The last of the devices built - the "Joint European Tor" in England - is a smaller prototype of a thermonuclear reactor, which at the final stage scientific research reached a Q value of almost 1. This means that it produced exactly the same amount of energy as it consumed. ITER will surpass this by demonstrating the creation of energy from fusion and achieving a Q value of 10. The idea is to generate 500 MW with an energy consumption of about 50 MW. Thus, one of the scientific goals of ITER is to prove that a Q value of 10 can be achieved.

Another scientific goal is that ITER will have a very long "burn" time - a pulse of increased duration up to one hour. ITER is a research experimental reactor that cannot produce energy continuously. When ITER starts operating, it will be on for one hour, after which it will need to be turned off. This is important because until now the standard devices we have been creating have been able to have a burning time of several seconds or even tenths of a second - this is the maximum. The "Joint European torus" reached its Q value of 1 with a burning time of approximately two seconds with a pulse length of 20 seconds. But a process that lasts a few seconds is not truly permanent. By analogy with starting a car engine: turning on the engine for a short time and then turning it off is not the real operation of the car. Only when you drive your car for half an hour, it will enter a permanent mode of operation and demonstrate that such a car can really be driven.

That is, from a technical and scientific point of view, ITER will provide a Q value of 10 and an increased burning time.

The thermonuclear fusion program has a truly international, broad character. People are already counting on the success of ITER and are thinking about the next step - creating a prototype industrial thermonuclear reactor called DEMO. To build it, it is necessary that ITER work. We must achieve our scientific goals, because this will mean that the ideas we put forward are quite feasible. However, I agree that you should always think about what will happen next. In addition, during the operation of ITER for 25-30 years, our knowledge will gradually deepen and expand, and we will be able to more accurately outline our next step.

Indeed, there is no dispute about whether ITER should be exactly a tokamak. Some scholars put the question quite differently: should there be ITER? Experts in different countries, developing their own, not so large-scale thermonuclear projects, argue that such a large reactor is not needed at all.

However, their opinion is hardly worth considering authoritative. Physicists who have been working with toroidal traps for several decades have been involved in the creation of ITER. The design of the experimental thermonuclear reactor in Karadash was based on all the knowledge gained in the course of experiments on dozens of precursor tokamaks. And these results indicate that the reactor must have a tokamak, and a large one at that.

JET At the moment, the most successful tokamak can be considered JET, built by the EU in the British town of Abingdon. This is the largest of the tokamak-type reactors created to date, the large radius of the plasma torus is 2.96 meters. The power of the thermonuclear reaction already reaches more than 20 megawatts with a retention time of up to 10 seconds. The reactor returns about 40% of the energy invested in the plasma.

It is plasma physics that determines the energy balance, - Igor Semenov told Infox.ru. What is the energy balance, MIPT Associate Professor described on simple example: “We all saw the fire burning. In fact, there is not firewood burning, but gas. The energy chain there is as follows: gas burns, firewood heats up, firewood evaporates, gas burns again. Therefore, if we throw water into the fire, we will sharply take energy from the system for the phase transition of liquid water into a vapor state. The balance will become negative, the fire will go out. There is another way - we can simply take and smash the firebrands in space. The fire will also go out. The same is true for the fusion reactor we are building. The dimensions are chosen so as to create an appropriate positive energy balance for this reactor. Sufficient to build a real TNPP in the future, solving at this experimental stage all the problems that currently remain unresolved.”

The dimensions of the reactor once changed. This happened at the turn of the 20th-21st century, when the United States withdrew from the project, and the remaining members realized that the ITER budget (at that time it was estimated at 10 billion US dollars) was too large. Physicists and engineers were required to reduce the cost of the installation. And this could be done only at the expense of size. The “redesign” of ITER was led by the French physicist Robert Aymar, who had previously worked on the French tokamak Tore Supra in Karadash. The outer radius of the plasma torus has been reduced from 8.2 meters to 6.3 meters. However, the risks associated with downsizing were partly offset by a few additional superconducting magnets, which made it possible to implement the then-discovered and explored plasma confinement regime.

 ITER(ITER) is a project of an international experimental thermonuclear reactor. The task of ITER is to demonstrate the possibility of commercial use of a fusion reactor and to solve the physical and technological problems that may be encountered along the way.
The design of the reactor has been completed and a site has been selected for its construction - the Cadarache research center (fr. Cadarache) in the south of France, in 60 km from Marseille. Currently (as of March 2012) are nearing completion of work on the creation of a reinforced concrete foundation for the reactor and the construction of walls in the pit.

Construction, the cost of which was originally estimated at 5 billion euros, originally planned to be completed in 2016 year, however, gradually the estimated amount of expenses doubled, and then the start date of the experiments shifted to 2020 year.
Initially, the name "ITER" was formed as an abbreviation of the English. International Thermonuclear Experimental Reactor, but at present it is not officially considered an abbreviation, but is associated with the word lat. iter − path.

Participating countries:

• EU countries (act as a whole)
• India
• China
• The Republic of Korea
• Russia
• Japan

The Kurchatov Institute, the State Atomic Energy Corporation Rosatom, and the EFA Research Institute im. DV Efremova, NIKIET, Institute of Applied Physics RAS, TRINITI, FTI im. A. F. Ioffe, VNIINM, VNIIKP, Management Company"Science and Innovation".

Construction:

• 2010 − start of excavation of foundation pit.
• 2013 - the beginning of the construction of the complex.
• 2014 - arrival of the first parts.
• 2015 - the beginning of the assembly.
• 2019 - the end of the assembly.
• 2020 d. - the beginning of experiments with plasma.
• 2027 d. - experiments with deuterium-tritium plasma.

Site preparation

The ITER facilities will be located on a total of 180 ha the land of the commune of Saint-Paul-le-Durance (Provence-Alpes-Côte d'Azur, a region of southern France), which has already become home to the French nuclear research center CEA (Commissariat à l "énergie atomique, Commissariat of Atomic Energy).

The most important part of ITER is itself tokamak and all office space - will be located on the site in 1 km length and 400 m width. Construction is expected to last until 2017 of the year. The main work at this stage is carried out under the leadership of the French agency ITER, and in essence CEA.

In general, the ITER facilities will be 60 meters colossus of mass 23 thousand tons.

Technical details

ITER refers to fusion reactors of the type "tokamak". Two cores: deuterium and tritium fuse to form a helium nucleus (alpha particle) and a high-energy neutron.

Design characteristics:

• Overall radius of the structure − 10.7 m
• Height − 30 m
• Large plasma radius − 6.2 m
• Small plasma radius − 2.0 m
• Plasma volume − 837 m3
• Magnetic field − 5.3 T
• Maximum current in the plasma column − 15 MA
• Plasma external heating power − 40 MW
• Fusion power − 500 MW
• Power Gain − 10x
• Average temperature − 100 MK
• Pulse duration − 400 c

Radiation safety

A thermonuclear reactor is much safer than a nuclear reactor in terms of radiation. First of all, the amount of radioactive substances in it is relatively small. The energy that can be released as a result of any accident is also small and cannot lead to the destruction of the reactor. At the same time, there are several natural barriers in the design of the reactor that prevent the spread of radioactive substances. For example, the vacuum chamber and the shell of the cryostat must be sealed, otherwise the reactor simply cannot work. However, during the design of ITER, great attention was paid to radiation safety, both during normal operation and during possible accidents.

There are several sources of possible radioactive contamination:

1. radioactive isotope of hydrogen - tritium;
2. induced radioactivity in the installation materials as a result of neutron irradiation;
3. radioactive dust generated as a result of plasma impact on the first wall;
4. radioactive corrosion products that can form in the cooling system.

In order to prevent the spread of tritium and dust if they go beyond the vacuum chamber and cryostat, a special ventilation system will maintain a reduced pressure in the reactor building. Therefore, there will be no air leakage from the building, except through ventilation filters.