Already at the end of the 20th century, the problem of finding alternative energy sources became very relevant. Despite the fact that our planet is truly rich in natural resources, such as oil, coal, timber, etc., all these riches, unfortunately, are exhaustible. In addition, the needs of mankind are growing every day and we have to look for more and more new and perfect sources of energy.
For a long time, mankind has found one way or another to solve the issue of alternative energy sources, but the real breakthrough in the history of energy was the emergence of nuclear energy. Nuclear theory has come a long way in development before people learned how to use it for their own purposes. It all started back in 1896, when A. Becquerel registered invisible rays emitted by uranium ore, and which had a great penetrating power. Later this phenomenon was called radioactivity. The history of the development of nuclear energy contains several dozen outstanding names, including Soviet physicists. The final stage of development can be called 1939 - when Yu.B. Khariton and Ya.B. Zeldovich theoretically showed the possibility of a chain reaction of fission of uranium-235 nuclei. Further development of nuclear power went by leaps and bounds. According to the most rough estimates, the energy that is released by the fission of 1 kilogram of uranium can be compared with the energy that is obtained by burning 2,500,000 kg of coal.

But because of the outbreak of the war, all research was redirected to the military area. The first example of nuclear energy that a person was able to demonstrate to the whole world was the atomic bomb ... Then the hydrogen bomb ... Only years later, the scientific community turned its attention to more peaceful areas where the use of nuclear energy could be really useful.
Thus began the dawn of the youngest field of energy. Nuclear power plants (NPPs) began to appear, and the world's first NPP was built in the city of Obninsk, Kaluga Region. Today, there are several hundred nuclear power plants around the world. The development of nuclear energy has been incredibly fast. In less than 100 years, she was able to achieve an ultra-high level of technological development. The amount of energy that is released during the fission of uranium or plutonium nuclei is incomparably large - this made it possible to create large industrial-type nuclear power plants.
So how do you get this energy? It's all about the chain reaction of nuclear fission of some radioactive elements. Usually uranium-235 or plutonium is used. Nuclear fission begins when a neutron enters it - an elementary particle that has no charge, but has a relatively large mass (0.14% more than the mass of a proton). As a result, fission fragments and new neutrons are formed, which have high kinetic energy, which in turn is actively converted into heat.

This type of energy is produced not only in nuclear power plants. It is also used on nuclear submarines and nuclear icebreakers.
For the normal functioning of nuclear power plants, they still need fuel. As a rule, it is uranium. This element is widely distributed in nature, but is difficult to access. In nature, there are no deposits of uranium (such as oil), it is, as it were, "smeared" over the entire earth's crust. The richest uranium ores, which are very rare, contain up to 10% pure uranium. Uranium is commonly found in uranium-bearing minerals as an isomorphic replacement element. But with all this, the total amount of uranium on the planet is grandiosely large. Perhaps in the near future, the latest technologies will increase the percentage of uranium production.
But such a powerful source of energy, and hence strength, cannot but cause concern. There is constant debate about its reliability and safety. It is difficult to assess what damage nuclear energy does to the environment. Is it so effective and profitable that such losses can be neglected? How safe is it? Moreover, unlike any other energy sector, it is not only about environmental safety. Everyone remembers the terrible consequences of the events in Hiroshima and Nagasaki. When humanity has such power, the question arises, is it worthy of such power? Will we be able to adequately dispose of what we have and not destroy it?
If tomorrow our planet ran out of all the reserves of traditional energy sources, then nuclear energy would probably become the only area that could really replace it. Its benefits cannot be denied, but the possible consequences should not be forgotten either.

Atom It consists of a nucleus around which particles called electrons revolve.

The nuclei of atoms are the smallest particles. They are the basis for all substance and matter.

They contain a large amount of energy.

This energy is released as radiation when certain radioactive elements decay. Radiation is dangerous for all life on earth, but at the same time it is used to produce electricity and in medicine.

Radioactivity is the property of the nuclei of unstable atoms to radiate energy. Most heavy atoms are unstable, and lighter atoms have radioisotopes, i.e. radioactive isotopes. The reason for the appearance of radioactivity is that the atoms strive to obtain stability. Today, three types of radioactive radiation are known: alpha, beta and gamma. They were named after the first letters of the Greek alphabet. The nucleus first emits alpha or beta rays. But if it still remains unstable, then gamma rays come out. Three atomic nuclei can be unstable, and each of them can emit any of the types of rays.

The figure shows three atomic nuclei.

They are unstable and each of them emits one of three types of beams.

Alpha particles have two protons and two neutrons. The core of the helium atom has exactly the same composition. Alpha particles move slowly and therefore any material thicker than a paper sheet can hold them. They are not much different from the nuclei of helium atoms. Most scientists put forward the version that helium on Earth is of natural radioactive origin.

Beta particles are electrons with enormous energy. Their formation occurs during the decay of neutrons. Beta particles are also not very fast, they can fly through the air up to one meter. Therefore, a millimeter-thick copper sheet can become an obstacle in their path. And if you set up a 13 mm lead barrier or 120 meters of air, you can halve gamma radiation.

Gamma rays are electromagnetic radiation of great energy. Its speed of movement is equal to the speed of light.

Transportation of radioactive substances is carried out in special lead containers with thick walls to prevent leakage of radiation.

Exposure to radiation is extremely dangerous for humans.

It causes burns, cataracts, provokes the development of cancer.

A special device, the Geiger counter, helps to measure the level of radiation, which makes clicking sounds when a source of radiation appears.

When a nucleus emits particles, it turns into the nucleus of another element, thus changing its atomic number. This is called the decay period of the element. But if the newly formed element is still unstable, then the decay process continues. And so on until the element becomes stable. For many radioactive elements, this period takes tens, hundreds and even thousands of years, so it is customary to measure the half-life. Take, for example, a plutonium-2 atom with a mass of 242. After emitting alpha particles with a relative atomic mass of 4, it becomes a uranium-238 atom with the same atomic mass.

Nuclear reactions.

Nuclear reactions are divided into two types: nuclear fusion and fission (splitting) of the nucleus.

Synthesis or otherwise "connection" means the connection of two nuclei into one large one under the influence of very high temperature. At this point, a large amount of energy is released.

During fission and fission, the process of fission of the nucleus occurs, while releasing nuclear energy.

This happens when the nucleus is bombarded with neutrons in a special device called a "particle accelerator".

During the fission of the nucleus and the radiation of neutrons, just a colossal amount of energy is released.

It is known that to obtain a large amount of electricity, only a unit mass of radio fuel is needed.No other power plant can boast of anything like it.

Nuclear power.

Thus, the energy that is released during a nuclear reaction is used to generate electricity or as an energy source in underwater and surface ships. The process of generating electricity at a nuclear power plant is based on nuclear fission in nuclear reactors. In a huge tank are rods of a radioactive substance (for example, uranium).

They are attacked by neutrons and split, releasing energy. New neutrons are split further and further. This is called a chain reaction. The efficiency of this method of generating electricity is incredibly high, but the security measures and burial conditions are too expensive.

However, mankind uses nuclear energy not only for peaceful purposes. In the middle of the 20th century, nuclear weapons were tested and tested.

Its action is to release a huge flow of energy, which leads to an explosion. At the end of World War II, the United States used nuclear weapons against Japan. They dropped atomic bombs on the cities of Hiroshima and Nagasaki.

The consequences were simply disastrous.

Some human victims were several hundred thousand.

But scientists did not stop there and developed hydrogen weapons.

Their difference is that nuclear bombs are based on nuclear fission reactions, and hydrogen bombs on fusion reactions.

radiocarbon method.

To obtain information about the time of death of an organism, the method of radiocarbon analysis is used. It is known that living tissue contains some amount of carbon-14, which is a radioactive isotope of carbon. The half-life of which is 5700 years. After the death of the organism, the reserves of carbon-14 in the tissues decrease, the isotope decays, and the time of death of the organism is determined from its remaining amount. So, for example, you can find out how long ago a volcano erupted. This can be recognized by insects and pollen frozen in lava.

How else is radioactivity used?

Radiation is also used in industry.

Gamma rays are used to irradiate food to keep it fresh.

In medicine, radiation is used in the study of internal organs.

There is also a technique called radiotherapy. This is when the patient is irradiated with small doses, destroying cancer cells in his body.

Atomic energy is the energy released in the process of transformation of atomic nuclei. The source of atomic energy is the internal energy of the atomic nucleus.

A more accurate name for atomic energy is nuclear energy. There are two types of nuclear energy production:
- implementation of a nuclear chain reaction of fission of heavy nuclei;
- the implementation of a thermonuclear fusion reaction of light nuclei.

Myths about atomic energy

The world's uranium reserves are running out. Even a child knows about the depletion of natural resources in our time. And indeed, the reserves of many minerals are rapidly drying up. Uranium reserves are currently rated as "relatively limited", but that's not all that small. For comparison, there is as much uranium as tin and 600 times more than gold. According to preliminary estimates of scientists, the reserves of this radioactive metal should be enough for mankind for the next 500 years. In addition, modern reactors can use thorium as fuel, and its world reserves, in turn, exceed those of uranium by 3 times.

Nuclear energy has an extremely negative impact on the environment. Representatives of various anti-nuclear campaigns often claim that nuclear energy contains "hidden emissions" of gases that have a negative impact on the environment. But according to all modern information and calculations, nuclear energy, even compared to solar or hydropower, which are considered practically environmentally friendly, contains a fairly low level of carbon.

Wind and wave energy are much less harmful from an environmental point of view. In reality, wind farms are being built or have already been built on the most important coastal sites, and the construction itself is already definitely polluting the environment. And the construction of wave stations is still experimental, and its impact on the environment is not exactly known, so they can hardly be called much more environmentally sustainable compared to nuclear energy.

In the territory where nuclear reactors are located, the level of leukemia is higher. The level of leukemia among children in the vicinity of the nuclear power plant is no higher than, for example, in areas near the so-called organic farms. The territory of the spread of this disease can cover both the territory around the nuclear power plant and the national park, the degree of danger is absolutely the same.

Nuclear reactors produce too much waste. In fact, nuclear energy produces minimal waste, contrary to the claims of environmentalists. The earth is not at all filled with radioactive waste. Modern technologies for the production of nuclear energy will make it possible to minimize the share of the total amount of radioactive waste over the next 20-40 years.

Atomic energy contributes to the spread of weapons in the world. An increase in the number of nuclear power plants will lead precisely to a reduction in the spread of weapons. Nuclear warheads produce very good quality reactor fuel, and reactor warheads produce about 15% of the world's nuclear fuel. Increasing demand for reactor fuel is expected to "distract" such warheads from would-be terrorists.

Terrorists choose nuclear reactors as targets. After the tragedy of September 11, 2001, a number of scientific studies were carried out in order to determine the likelihood of an attack on nuclear facilities. However, recent British studies have shown that nuclear power plants are quite capable of "surviving" even a Boeing 767-400 raid. The new generation of nuclear reactors will be designed with increased levels of protection against potential attacks from all existing aircraft, and it is also planned to introduce special safety features that can be activated without human intervention or computer control.

Nuclear energy is very costly. Controversial assertion. According to the British Department of Trade and Industry, the cost of generating electricity from nuclear plants exceeds only the price of gas, and 10-20 times less than the energy produced by onshore wind farms. In addition, 10% of the total cost of nuclear energy comes from uranium, and nuclear energy is not so exposed to constant fluctuations in the prices of fuels such as gas or oil.

Decommissioning a nuclear power plant is very expensive. This statement applies only to nuclear power plants built earlier. Many of the existing nuclear reactors were built without the expectation of their subsequent decommissioning. But when building new nuclear power plants, this point will already be taken into account. However, the cost of decommissioning a nuclear power plant will be included in the cost of electricity paid by consumers. Modern reactors are designed to operate for 40 years, and the decommissioning fee will be paid over that long period, and therefore will have little effect on the price of electricity.

Building a nuclear power plant takes too long. This is perhaps the most unmotivated of all anti-nuclear campaign statements. The construction of a nuclear power plant takes from 4 to 6 years, which is comparable to the construction time of "traditional" power plants. The modular structure of new nuclear power plants can somewhat speed up the process of building nuclear power plants.

The energy of a nuclear reaction is concentrated in the nucleus of an atom. An atom is the tiny particle that makes up all matter in the universe.

The amount of energy in nuclear fission is enormous and can be used to create electricity, but it must first be freed from the atom.

Getting energy

The use of the energy of a nuclear reaction occurs with the help of equipment that can control atomic fission to produce electricity.

The fuel used for reactors and power generation is most often pellets of the element uranium. In a nuclear reactor, uranium atoms are forced to fall apart. When they separate, the atoms release tiny particles called fission products. The fission products act on other uranium atoms to separate - a chain reaction begins. The core energy released from this chain reaction creates heat. The heat from the nuclear reactor makes it very hot, so it must be cooled down. The technologically best coolant is usually water, but some nuclear reactors use liquid metal or molten salts. The coolant, heated from the core, produces steam. The steam acts on the steam turbine by turning it. The turbine is mechanically connected to a generator that generates electricity.
The reactors are controlled by control rods that can be adjusted to the amount of heat generated. Control rods are made from materials like cadmium, hafnium or boron to absorb some of the products created by nuclear fission. The rods are present during the chain reaction to control the reaction. Removing the rods will allow the chain reaction to develop more strongly and create more electricity.

About 15 percent of the world's electricity is generated by nuclear power plants.

The United States has over 100 reactors, although the US generates most of its electricity from fossil fuels and hydroelectric power.

In Russia, there are 33 power units at 10 nuclear power plants - 15% of the country's energy balance.

Lithuania, France and Slovakia consume most of their electricity from nuclear power plants.

Nuclear fuel used to generate energy

Uranium is the fuel most widely used to generate nuclear reaction energy. This is because uranium atoms break apart relatively easily. A specific type of uranium for production, called U-235, is rare. U-235 makes up less than one percent of the world's uranium.

Uranium is mined in Australia, Canada, Kazakhstan, Russia, Uzbekistan and must be processed before it can be used.

Since nuclear fuel can be used to create weapons, production refers to a non-proliferation treaty for such weapons by importing uranium or plutonium or other nuclear fuel. The treaty promotes the peaceful use of fuel, as well as limiting the spread of these types of weapons.

Nuclear energy and people

Nuclear nuclear power produces electricity that can be used to power homes, schools, businesses and hospitals.

The first reactor to produce electricity was built in Idaho, USA and experimentally started to power itself in 1951.

In 1954, the first nuclear power plant was established in Obninsk, Russia, designed to provide energy to people.

Building reactors to extract the energy of a nuclear reaction requires a high level of technology and only countries that have signed a non-proliferation treaty can obtain the uranium or plutonium that is required. For these reasons, most nuclear power plants are located in the developed countries of the world.

Nuclear power plants produce renewable, environmentally friendly resources. They do not pollute the air or produce greenhouse gas emissions. They can be built in urban or rural areas and do not drastically change the environment around them.

Radioactive material of power plants

radioactive material in r The reactor is safe as it is cooled in a separate structure called a cooling tower. The steam turns back into water and can be used again to generate electricity. Excess steam is simply recycled into the atmosphere, where it does not harm like pure water.

However, the energy of a nuclear reaction has a by-product in the form of radioactive material. Radioactive material is a collection of unstable nuclei. These nuclei lose their energy and can affect many materials around them, including living organisms and the environment. The radioactive material can be extremely toxic, causing disease, increasing the risk for cancer, blood disease and bone decay.

Radioactive waste is what is left from the operation of a nuclear reactor.

The radioactive waste covers protective clothing worn by workers, tools and fabrics that have been in contact with the radioactive dust. Radioactive waste is durable. Materials like clothes and tools can be radioactive for thousands of years. The government regulates how these materials are disposed of so as not to contaminate anything else.

The fuel and rods used are extremely radioactive. Used uranium pellets must be stored in special containers that look like large pools. Some plants store used fuel in above-ground dry storage tanks.

The water cooling the fuel does not come into contact with radioactivity and is therefore safe.

They are also known for which the principle of operation is somewhat different.

Use of atomic energy and radiation safety

Critics of the use of nuclear reaction energy worry that radioactive waste storage facilities will leak, crack or collapse. The radioactive material could then contaminate the soil and groundwater near the facility. This can lead to serious health problems for people and living organisms in the area. All people would have to evacuate.

This is what happened in Chernobyl, Ukraine, in 1986. A steam explosion in one of the power plants of the fourth nuclear reactor destroyed it and started a fire. A cloud of radioactive particles was formed, which fell to the ground or drifted with the wind, and the particles entered the water cycle in nature as rain. Most of the radioactive fallout fell in Belarus.

The environmental consequences of the Chernobyl disaster occurred immediately. Kilometers around the site, the pine forest has dried up, and the red color of the dead pines has been nicknamed the Red Forest in the area. Fish from the nearby Pripyat River have received radioactivity and people will no longer be able to consume it. Cattle and horses died. More than 100,000 people have been evacuated since the disaster, but the number of human casualties from Chernobyl is difficult to determine.

The effects of radiation poisoning appear only after many years. In diseases such as cancer, it is difficult to determine the source.

The future of nuclear energy

Reactors use the fission or splitting of atoms to produce energy.

Nuclear reaction energy can also be produced by fusing or joining atoms together. Produced. The sun, for example, is constantly undergoing nuclear fusion of hydrogen atoms to form helium. Since life on our planet depends on the Sun, it can be said that the splitting makes life on Earth possible.

Nuclear power plants do not yet have the ability to safely and reliably produce energy through nuclear fusion (fusion), but scientists are investigating nuclear fusion because the process is likely to be safer and more cost-effective as an alternative form of energy.

The energy of a nuclear reaction is enormous and must be used by people.

At the end of the last century, scientists were surprised to discover that atoms, or rather the nuclei of atoms, fall apart by themselves, emitting rays and heat. They called this phenomenon . And when they calculated, they were even more surprised: 1 g of radium, if it completely decays, can give as much heat as 500 kg of coal give by burning. But it is impossible to use this property - atoms decay so slowly that only half of the heat is released in 2000 years.

It's like a big dam. The dam is closed, and the water flows in a small stream that is of no use.

Now, if the dam were opened, if people learned how to destroy atoms!.. They would receive an endless ocean of energy. But how to do that?

They say that they don’t shoot at a sparrow from a cannon, they need a small pellet. And where to get a pellet to split the nucleus of an atom?

Scientists all over the Earth have been hard at work for several decades. During this time, they learned how it works, and found a "shot" for it. It turned out to be one of the particles that is part of the nucleus - the neutron. It easily penetrates the atom and breaks the nucleus.

And then it turned out that the atoms of the uranium metal, having split, emit new neutrons that destroy neighboring atoms. If you take a piece of uranium, in which many nuclei will simultaneously decay and many new neutrons will be released, the fission process will grow like an avalanche in the mountains. An atomic bomb will explode.

The scheme of the device of a nuclear reactor. Thick black rods are neutron absorbers. In the reactor, the water is heated, and then heats the water in the heat exchanger to a boil. The resulting steam rotates the turbine of the power plant.

Imagine that a large dam has collapsed. The water collected behind it all immediately rushes violently down. The power of the stream is great, but only harm from it, because it sweeps away everything in its path. So it is with the atom: the colossal energy of the explosion can only destroy. And people need atomic energy to build. Now, if the atom gave away its reserves in such portions as we want! No energy needed - closed the damper. It took - (How much do you need?) opened two or three dampers: “Get as much as you asked for!”

And the man curbed the explosion.

Who is the main "worker" at the "nuclear plant"? Neutron. It is he who breaks the uranium nuclei. And if we remove some of the workers from the "factory"? Work will go slower.

This is how an atomic boiler, or a nuclear reactor, works. This is a large well with thick concrete walls (they are needed so that radiation harmful to people does not go outside). The well is filled with graphite, the same material used to make pencil leads. There are holes in the graphite filling where uranium rods are placed. When there are enough of them, the required number of “working” neutrons appears and an atomic reaction begins.

To control it, there are rods of metal in other holes, which captures and absorbs neutrons. This is the "flaps" in the dam.

No energy is needed or there is a danger of an explosion, the shutter-rods are instantly lowered, the neutrons emitted from the uranium nuclei are absorbed, stop working, and the reaction stops.

It is necessary for the reaction to start, the shutter rods are raised, “working” neutrons appear in the reactor again, and the temperature in the boiler rises (How much energy do you need? Get it!).

Nuclear reactors can be placed on nuclear power plants, on nuclear submarines, on a nuclear icebreaker. They, like ordinary steam boilers, obediently turn water into steam, which will rotate the turbines. Five hundred kilograms of atomic fuel - the contents of only ten suitcases - is enough for the Lenin icebreaker to sail all year round. Can you imagine how profitable it is: you don’t need to carry hundreds of tons of fuel with you, you can take a more useful cargo instead; you can not go to the port for refueling for a whole year, especially since in the North this is not always easy to do. Yes, and machines can be put stronger ...

In existing nuclear reactors, energy is obtained by destroying nuclei consisting of a large number of particles (in uranium nuclei, for example, there are more than two hundred of them). And although there is still a lot of such fuel on Earth, but someday it will run out ... Is there a way to get nuclear energy from other substances? And scientists have found!

It turned out that atoms, in the nucleus of which there are only two particles: one proton and one neutron, can also serve as a source of energy. But they don’t give it away when they divide, but when they combine, or, as they say, during synthesis, two nuclei.

Hydrogen atoms for this need to be heated to many millions of degrees. At this temperature, their nuclei begin to move at great speed and, having accelerated, they can overcome the electrical repulsive forces that exist between them. When they get close enough, the nuclear forces of attraction begin to act and the nuclei merge. Thousands of times more heat is released than during nuclear fission.

This method of obtaining energy is called a thermonuclear reaction. These reactions rage in the depths of both distant stars and the nearby Sun, which gives us light and heat. But on Earth, they have so far manifested themselves in the form of a devastating explosion of a hydrogen bomb.

Now scientists are working to make hydrogen nuclei combine gradually. And when we learn how to control thermonuclear reactions, we will be able to take advantage of the unlimited reserves of energy contained in water, which consists of hydrogen and whose reserves are inexhaustible.