For Russia, the energy of the Earth's heat can become a constant, reliable source of providing cheap and affordable electricity and heat using new high, environmentally friendly technologies for its extraction and supply to the consumer. This is especially true at the moment

Limited resources of fossil energy raw materials

The demand for organic energy raw materials is great in industrialized and developing countries (USA, Japan, states of united Europe, China, India, etc.). At the same time, their own hydrocarbon resources in these countries are either insufficient or reserved, and a country, such as the United States, buys energy raw materials abroad or develops deposits in other countries.

In Russia, one of the richest countries in terms of energy resources, the economic needs for energy are still satisfied by the possibilities of using natural resources. However, the extraction of fossil hydrocarbons from the bowels is very rapidly. If in the 1940s-1960s. The main oil-producing regions were the "Second Baku" in the Volga and Cis-Urals, then, starting from the 1970s, and to the present, Western Siberia has been such an area. But even here there is a significant decline in the production of fossil hydrocarbons. The era of "dry" Cenomanian gas is passing away. The previous stage of extensive development of natural gas production has come to an end. Its extraction from such giant deposits as Medvezhye, Urengoyskoye and Yamburgskoye amounted to 84, 65 and 50%, respectively. The proportion of oil reserves favorable for development also decreases over time.

Due to the active consumption of hydrocarbon fuels, onshore reserves of oil and natural gas have been significantly reduced. Now their main reserves are concentrated on continental shelf. And although raw material base oil and gas industry is still sufficient for oil and gas production in Russia in required volumes, in the near future it will be provided to an increasing extent through the development of deposits with complex mining and geological conditions. At the same time, the cost of hydrocarbon production will grow.

Most of the non-renewable resources extracted from the subsoil are used as fuel for power plants. First of all, this is the share of which in the fuel structure is 64%.

In Russia, 70% of electricity is generated at thermal power plants. Energy enterprises of the country annually burn about 500 million tons of c.e. tons for the purpose of generating electricity and heat, while the production of heat consumes 3-4 times more hydrocarbon fuel than the generation of electricity.

The amount of heat obtained from the combustion of these volumes of hydrocarbon raw materials is equivalent to the use of hundreds of tons of nuclear fuel - the difference is huge. However nuclear energy requires provision environmental safety(to prevent a repeat of Chernobyl) and protect it from possible terrorist attacks, as well as the safe and costly decommissioning of obsolete and spent nuclear power units. The proven recoverable reserves of uranium in the world are about 3 million 400 thousand tons. For the entire previous period (until 2007), about 2 million tons were mined.

RES as the future of global energy

The increased interest in the world in recent decades in alternative renewable energy sources (RES) is caused not only by the depletion of hydrocarbon fuel reserves, but also by the need to solve environmental problems. Objective factors (fossil fuel and uranium reserves, as well as changes in environment associated with the use of traditional fire and nuclear energy) and energy development trends suggest that the transition to new methods and forms of energy production is inevitable. Already in the first half of the XXI century. there will be a complete or almost complete transition to non-traditional energy sources.

The sooner a breakthrough is made in this direction, the less painful it will be for the whole society and more beneficial for the country where decisive steps in the indicated direction.

The world economy has already set a course for the transition to a rational combination of traditional and new energy sources. Energy consumption in the world by 2000 amounted to more than 18 billion tons of fuel equivalent. tons, and energy consumption by 2025 may increase to 30–38 billion tons of fuel equivalent. tons, according to forecast data, by 2050 consumption at the level of 60 billion tons of fuel equivalent is possible. t. A characteristic trend in the development of the world economy in the period under review is a systematic decrease in the consumption of fossil fuels and a corresponding increase in the use of non-traditional energy resources. The thermal energy of the Earth occupies one of the first places among them.

At present, the Ministry of Energy of the Russian Federation has adopted a development program non-traditional energy, including 30 major projects the use of heat pump installations (HPU), the principle of operation of which is based on the consumption of low-potential thermal energy of the Earth.

Low-potential energy of the Earth's heat and heat pumps

The sources of low-potential heat energy of the Earth are solar radiation and thermal radiation heated bowels of our planet. At present, the use of such energy is one of the most dynamically developing areas of energy based on renewable energy sources.

The heat of the earth can be used in various types buildings and structures for heating, hot water supply, air conditioning (cooling), as well as for heating paths in winter time years, prevention of icing, heating of fields in open stadiums, etc. In the English-language technical literature, systems that utilize the Earth's heat in heating and air conditioning systems are referred to as GHP - "geothermal heat pumps" (geothermal heat pumps). Climatic characteristics of the countries of Central and Northern Europe, which, together with the USA and Canada, are the main areas for the use of low-grade heat of the Earth, determine this mainly for heating purposes; cooling of the air, even in summer, is relatively rarely required. Therefore, unlike in the USA, heat pumps in European countries operate mainly in heating mode. In the US, they are more often used in air heating systems combined with ventilation, which allows both heating and cooling of the outside air. In European countries, heat pumps are usually used in water heating systems. Since their efficiency increases as the temperature difference between the evaporator and condenser decreases, floor heating systems are often used for heating buildings, in which a coolant of a relatively low temperature (35–40 ° C) circulates.

Types of systems for the use of low-potential energy of the Earth's heat

AT general case There are two types of systems for using the low-potential energy of the Earth's heat:

- open systems: as a source of low-grade thermal energy, groundwater is used, which is supplied directly to heat pumps;

- closed systems: heat exchangers are located in the soil massif; when a coolant with a temperature lower than the ground circulates through them, thermal energy is “taken off” from the ground and transferred to the heat pump evaporator (or when a coolant with a higher temperature relative to the ground is used, it is cooled).

Minuses open systems are that the wells require maintenance. In addition, the use of such systems is not possible in all areas. The main requirements for soil and groundwater are as follows:

- sufficient water permeability of the soil, allowing replenishment of water reserves;

– good chemical composition ground water(e.g. low iron content) to avoid pipe scale and corrosion problems.

Closed systems for the use of low-potential energy of the Earth's heat

Closed systems are horizontal and vertical (Figure 1).

Rice. 1. Scheme of a geothermal heat pump installation with: a - horizontal

and b - vertical ground heat exchangers.

Horizontal ground heat exchanger

In the countries of Western and Central Europe, horizontal ground heat exchangers usually they are separate pipes laid relatively tightly and interconnected in series or in parallel (Fig. 2).

Rice. 2. Horizontal ground heat exchangers with: a - sequential and

b - parallel connection.

To save the area of ​​the site where the heat is removed, improved types of heat exchangers have been developed, for example, heat exchangers in the form of a spiral (Fig. 3), located horizontally or vertically. This form of heat exchangers is common in the USA.

Since ancient times, people have known about the elemental manifestations of gigantic energy lurking in the depths the globe. The memory of mankind keeps legends about catastrophic volcanic eruptions that claimed millions human lives, unrecognizably changed the face of many places on Earth. The power of the eruption of even a relatively small volcano is colossal, it many times exceeds the power of the largest power plants created by human hands. True, there is no need to talk about the direct use of the energy of volcanic eruptions: people do not yet have the opportunity to curb this recalcitrant element, and, fortunately, these eruptions are quite rare events. But these are manifestations of the energy lurking in the bowels of the earth, when only a tiny fraction of this inexhaustible energy finds a way out through the fire-breathing vents of volcanoes.

Small European country Iceland (“country of ice” in literal translation) is fully self-sufficient in tomatoes, apples and even bananas! Numerous Icelandic greenhouses are powered by the heat of the earth, there are practically no other local sources of energy in Iceland. But this country is very rich hot springs and famous geysers - fountains of hot water, with the precision of a chronometer escaping from the ground. And although Icelanders do not have priority in using the heat of underground sources (even the ancient Romans brought water from under the ground to the famous baths - the baths of Caracalla), the inhabitants of this small northern country operate the underground boiler house very intensively. The capital city of Reykjavik, where half of the country's population lives, is heated only by underground sources. Reykjavik is perfect a starting point to get to know Iceland: from here you can go on the most interesting and varied excursions to any corner of this unique country: geysers, volcanoes, waterfalls, rhyolite mountains, fjords ... Everywhere in Reykjavik you will feel PURE ENERGY - the thermal energy of geysers gushing out of the ground , the energy of purity and space of an ideally green city, the energy of a cheerful and incendiary nightlife Reykjavik all year round.

But not only for heating people draw energy from the depths of the earth. Power plants using hot underground springs have been operating for a long time. The first such power plant, still very low-power, was built in 1904 in the small Italian town of Larderello, named after the French engineer Larderelli, who back in 1827 drew up a project for the use of numerous hot springs in the area. Gradually, the capacity of the power plant grew, more and more new units came into operation, new sources of hot water were used, and today the power of the station has already reached an impressive value - 360 thousand kilowatts. In New Zealand, there is such a power plant in the Wairakei region, its capacity is 160,000 kilowatts. A geothermal plant with a capacity of 500,000 kilowatts produces electricity 120 km from San Francisco in the United States.

geothermal energy

Since ancient times, people have known about the spontaneous manifestations of gigantic energy lurking in the bowels of the globe. The memory of mankind keeps legends about catastrophic volcanic eruptions that claimed millions of human lives, unrecognizably changed the appearance of many places on Earth. The power of the eruption of even a relatively small volcano is colossal, it many times exceeds the power of the largest power plants created by human hands. True, there is no need to talk about the direct use of the energy of volcanic eruptions - so far people do not have the opportunity to curb this recalcitrant element, and, fortunately, these eruptions are quite rare events. But these are manifestations of the energy lurking in the bowels of the earth, when only a tiny fraction of this inexhaustible energy finds a way out through the fire-breathing vents of volcanoes.

The geyser is hot spring, which erupts its water to regular or irregular heights, like a fountain. The name comes from the Icelandic word for "pours". The appearance of geysers requires a certain favorable environment, which was created only in a few places on earth, which leads to their rather rare presence. Almost 50% of geysers are located in the Yellowstone National Park (USA). The activity of the geyser may stop due to changes in the bowels, earthquakes and other factors. The action of a geyser is caused by the contact of water with magma, after which the water quickly heats up and, under the influence of geothermal energy, is thrown upward with force. After the eruption, the water in the geyser gradually cools, seeps back to the magma, and again gushing. The frequency of eruptions of various geysers varies from several minutes to several hours. The need for great energy for the action of a geyser is the main reason for their rarity. Volcanic areas may have hot springs, mud volcanoes, fumaroles, but there are very few places where geysers are located. The fact is that even if a geyser formed at the site of volcano activity, subsequent eruptions will destroy the surface of the earth and change its state, which will lead to the disappearance of the geyser.

Energy of the earth ( geothermal energy) is based on the use of the natural heat of the Earth. The bowels of the Earth are fraught with a colossal, almost inexhaustible source of energy. The annual radiation of internal heat on our planet is 2.8 * 1014 billion kWh. It is constantly compensated by the radioactive decay of some isotopes in the earth's crust.

Geothermal energy sources can be of two types. The first type is underground pools of natural heat carriers - hot water (hydrothermal springs), or steam (steam thermal springs), or a steam-water mixture. In essence, these are directly ready-to-use "underground boilers" from where water or steam can be extracted using ordinary boreholes. The second type is the warmth of hot rocks. By pumping water into such horizons, one can also obtain steam or superheated water for further use for energy purposes.

But in both use cases, the main disadvantage is, perhaps, a very low concentration of geothermal energy. However, in places of formation of peculiar geothermal anomalies, where hot springs or rocks come relatively close to the surface and where the temperature rises by 30-40 ° C for every 100 m, concentrations of geothermal energy can create conditions for its economic use. Depending on the temperature of water, steam or steam-water mixture, geothermal sources are divided into low and medium temperature (with temperatures up to 130 - 150 ° C) and high temperature (over 150 °). The nature of their use largely depends on the temperature.

It can be argued that geothermal energy has four beneficial features.

First, its reserves are practically inexhaustible. According to estimates of the late 70s, to a depth of 10 km, they amount to a value that is 3.5 thousand times higher than the reserves traditional types mineral fuel.

Secondly, geothermal energy is quite widespread. Its concentration is associated mainly with belts of active seismic and volcanic activity, which occupy 1/10 of the Earth's area. Within these belts, some of the most promising "geothermal regions" can be distinguished, examples of which are California in the USA, New Zealand, Japan, Iceland, Kamchatka, and the North Caucasus in Russia. Only in former USSR by the beginning of the 1990s, about 50 underground pools of hot water and steam had been opened.

Thirdly, the use of geothermal energy does not require high costs, because. in this case we are talking about already “ready-to-use” sources of energy created by nature itself.

Finally, fourthly, geothermal energy is environmentally completely harmless and does not pollute the environment.

Man has long been using the energy of the internal heat of the Earth (let us recall the famous Roman baths), but its commercial use began only in the 20s of our century with the construction of the first geoelectric power plants in Italy, and then in other countries. By the beginning of the 1980s, there were about 20 such stations operating in the world with a total capacity of 1.5 million kW. The largest of them is the Geysers station in the USA (500 thousand kW).

Geothermal energy is used to generate electricity, heat homes, greenhouses, etc. Dry steam, superheated water or any heat carrier with a low boiling point (ammonia, freon, etc.) is used as a heat carrier.

geothermal energy- this is the energy of heat that is released from the inner zones of the Earth over hundreds of millions of years. According to geological and geophysical studies, the temperature in the Earth's core reaches 3,000-6,000 °C, gradually decreasing in the direction from the center of the planet to its surface. The eruption of thousands of volcanoes, the movement of blocks of the earth's crust, earthquakes testify to the action of a powerful internal energy Earth. Scientists believe that the thermal field of our planet is due to radioactive decay in its depths, as well as the gravitational separation of the core matter.
The main sources of heating the bowels of the planet are uranium, thorium and radioactive potassium. Processes radioactive decay on the continents occur mainly in the granitic layer of the earth's crust at a depth of 20-30 km or more, in the oceans - in the upper mantle. It is assumed that at the bottom of the earth's crust at a depth of 10-15 km, the probable temperature value on the continents is 600-800 ° C, and in the oceans - 150-200 ° C.
A person can use geothermal energy only where it manifests itself close to the Earth's surface, i.e. in areas of volcanic and seismic activity. Now geothermal energy is effectively used by such countries as the USA, Italy, Iceland, Mexico, Japan, New Zealand, Russia, the Philippines, Hungary, El Salvador. Here, the internal heat of the earth rises to the very surface in the form of hot water and steam with temperatures up to 300 ° C and often breaks out as the heat of gushing springs (geysers), for example, the famous geysers yellowstone park in the USA, geysers of Kamchatka, Iceland.
Geothermal energy sources divided into dry hot steam, wet hot steam and hot water. The well, which is an important source of energy for electric railway in Italy (near the city of Larderello), since 1904 it has been feeding dry hot steam. Two other well-known places in the world with hot dry steam are the Matsukawa field in Japan and the geyser field near San Francisco, where geothermal energy has also been used effectively for a long time. Most of all in the world of wet hot steam is located in New Zealand (Wairakei), geothermal fields of slightly less power - in Mexico, Japan, El Salvador, Nicaragua, Russia.
Thus, four main types of geothermal energy resources can be distinguished:
surface heat of the earth used by heat pumps;
energetic resources couple, hot and warm water near the surface of the earth, which are now used in the production of electrical energy;
heat concentrated deep below the surface of the earth (perhaps in the absence of water);
magma energy and heat that accumulates under volcanoes.

Geothermal heat reserves (~ 8 * 1030J) are 35 billion times the annual global energy consumption. Only 1% of the geothermal energy of the earth's crust (depth of 10 km) can provide an amount of energy that is 500 times greater than all the world's oil and gas reserves. However, today only a small part of these resources can be used, and this is due primarily to economic reasons. The beginning of the industrial development of geothermal resources (energy of hot deep waters and steam) was laid in 1916, when the first geothermal power plant with a capacity of 7.5 MW was put into operation in Italy. Over the past time, considerable experience has been accumulated in the field of practical development of geothermal energy resources. The total installed capacity of operating geothermal power plants (GeoTPP) was: 1975 - 1,278 MW, in 1990 - 7,300 MW. The United States, the Philippines, Mexico, Italy, and Japan have achieved the greatest progress in this matter.
The technical and economic parameters of the GeoTPP vary over a fairly wide range and depend on the geological characteristics of the area (depth of occurrence, parameters of the working fluid, its composition, etc.). For the majority of commissioned GeoTPPs, the cost of electricity is similar to the cost of electricity produced at coal-fired TPPs, and amounts to 1200 ... 2000 US dollars / MW.
In Iceland, 80% of residential buildings are heated with hot water extracted from geothermal wells under the city of Reykjavik. In the western United States, about 180 homes and farms are heated by geothermal hot water. According to experts, between 1993 and 2000, global electricity generation from geothermal energy more than doubled. There are so many reserves of geothermal heat in the United States that it could theoretically provide 30 times more energy than the state currently consumes.
In the future, it is possible to use the heat of magma in those areas where it is located close to the Earth's surface, as well as the dry heat of heated crystalline rocks. AT last case wells are drilled for several kilometers, cold water is pumped down, and hot water is returned back.

With the development and formation of society, mankind began to look for more and more modern and at the same time economical ways to obtain energy. For this, various stations are being built today, but at the same time, the energy contained in the bowels of the earth is widely used. What is she like? Let's try to figure it out.

geothermal energy

Already from the name it is clear that it represents the heat of the earth's interior. Under the earth's crust is a layer of magma, which is a fiery-liquid silicate melt. According to research data, the energy potential of this heat is much higher than the energy of the world's natural gas reserves, as well as oil. Magma comes to the surface - lava. And most active observed in those layers of the earth on which the boundaries are located tectonic plates, and also where the earth's crust is characterized by thinness. The geothermal energy of the earth is obtained as follows: lava and water resources The planets collide, causing the water to heat up dramatically. This leads to the eruption of the geyser, the formation of the so-called hot lakes and undercurrents. That is, precisely those phenomena of nature, the properties of which are actively used as energies.

Artificial geothermal sources

The energy contained in the bowels of the earth must be used wisely. For example, there is an idea to create underground boilers. To do this, you need to drill two wells of sufficient depth, which will be connected at the bottom. That is, it turns out that in almost any corner of the land you can get geothermal energy. industrial way: through one well will be injected cold water into the reservoir, and through the second - hot water or steam is extracted. artificial sources heat will be profitable and rational if the resulting heat will give more energy. The steam can be sent to turbine generators that will generate electricity.

Of course, the heat taken away is only a fraction of what is available in general reserves. But it should be remembered that the deep heat will be constantly replenished due to the processes of compression of rocks, stratification of the bowels. According to experts, the earth's crust accumulates heat, total which is 5000 times more calorific value all the fossil resources of the earth as a whole. It turns out that the operating time of such artificially created geothermal stations can be unlimited.

Source Features

The sources that make it possible to obtain geothermal energy are almost impossible to fully use. They exist in more than 60 countries of the world, with the largest number of terrestrial volcanoes on the territory of the Pacific volcanic ring of fire. But in practice, it turns out that geothermal sources in different regions of the world are completely different in their properties, namely, average temperature, mineralization, gas composition, acidity and so on.

Geysers are sources of energy on Earth, the peculiarities of which are that they spew boiling water at certain intervals. After the eruption, the pool becomes free of water, at its bottom you can see a channel that goes deep into the ground. Geysers are used as energy sources in regions such as Kamchatka, Iceland, New Zealand and North America, and single geysers are found in several other areas.

Where does energy come from?

Quite close to earth's surface uncooled magma is located. Gases and vapors are released from it, which rise and pass through the cracks. Mixing with groundwater, they cause their heating, they themselves turn into hot water, in which many substances are dissolved. Such water is released to the surface of the earth in the form of various geothermal sources: hot springs, mineral springs, geysers, and so on. According to scientists, the hot bowels of the earth are caves or chambers connected by passages, cracks and channels. They are just filled with groundwater, and very close to them are magma chambers. In this natural way, the thermal energy of the earth is formed.

Earth's electric field

There is another alternative energy source in nature, which is renewable, environmentally friendly, and easy to use. True, so far this source has only been studied and not applied in practice. So, potential energy The earth lies in its electric field. It is possible to obtain energy in this way based on the study of the basic laws of electrostatics and the features of the Earth's electric field. In fact, our planet from an electrical point of view is a spherical capacitor charged up to 300,000 volts. Its inner sphere has negative charge, and the outer one - the ionosphere - is positive. is an insulator. Through it there is a constant flow of ionic and convective currents, which reach strengths of many thousands of amperes. However, the potential difference between the plates does not decrease in this case.

This suggests that in nature there is a generator, the role of which is to constantly replenish the leakage of charges from the capacitor plates. The magnetic field of the Earth acts as such a generator, rotating together with our planet in a stream solar wind. The energy of the Earth's magnetic field can be obtained just by connecting an energy consumer to this generator. To do this, you need to install a reliable ground.

Renewable sources

As the population of our planet is steadily growing, we need more and more energy to provide for the population. The energy contained in the bowels of the earth can be very different. For example, there are renewable sources: wind, solar and water energy. They are environmentally friendly, and therefore you can use them without fear of harming the environment.

water energy

This method has been used for many centuries. Today, a huge number of dams and reservoirs have been built, in which water is used to generate electrical energy. The essence of the operation of this mechanism is simple: under the influence of the flow of the river, the wheels of the turbines rotate, respectively, the energy of the water is converted into electrical energy.

Today there is a large number of hydroelectric power plants that convert the energy of the flow of water into electricity. The peculiarity of this method is that it is renewable, respectively, such designs have a low cost. That is why, despite the fact that the construction of hydroelectric power plants takes quite a long time, and the process itself is very costly, nevertheless, these facilities significantly outperform electric-intensive industries.

Solar energy: modern and promising

Solar energy is obtained using solar panels, however, modern technology allows the use of new methods for this. The largest system in the world is built in the California desert. It fully provides energy for 2,000 homes. The design works as follows: the sun's rays are reflected from the mirrors, which are sent to the central boiler with water. It boils and turns into steam, which turns the turbine. It, in turn, is connected to an electric generator. The wind can also be used as the energy that the Earth gives us. The wind blows the sails, turns the windmills. And now with its help you can create devices that will generate electrical energy. By rotating the blades of the windmill, it drives the turbine shaft, which, in turn, is connected to an electric generator.

Internal energy of the Earth

It appeared as a result of several processes, the main of which are accretion and radioactivity. According to scientists, the formation of the Earth and its mass took place over several million years, and this happened due to the formation of planetesimals. They stuck together, respectively, the mass of the Earth became more and more. After our planet began to have a modern mass, but was still devoid of an atmosphere, meteoric and asteroid bodies fell on it without hindrance. This process is just called accretion, and it led to the fact that a significant amount of gravitational energy. And the larger bodies hit the planet, the more released the energy contained in the bowels of the Earth.

This gravitational differentiation led to the fact that the substances began to delaminate: heavy substances they simply sank, while light and volatile ones floated up. Differentiation also affected the additional release of gravitational energy.

Atomic Energy

The use of earth energy can occur in different ways. For example, with the help of the construction of nuclear power plants, when thermal energy is released due to the decay smallest particles matter of atoms. The main fuel is uranium, which is contained in the earth's crust. Many believe that this method of obtaining energy is the most promising, but its use is associated with a number of problems. First, uranium emits radiation that kills all living organisms. In addition, if this substance enters the soil or atmosphere, then a real man-made disaster will occur. Sad consequences accidents on Chernobyl nuclear power plant we experience to this day. The danger lies in the fact that radioactive waste can threaten all living things very, very long time for millennia.

New time - new ideas

Of course, people do not stop there, and every year more and more attempts are made to find new ways to get energy. If the energy of the earth's heat is obtained quite simply, then some methods are not so simple. For example, as an energy source, it is quite possible to use biological gas, which is obtained during the decay of waste. It can be used for heating houses and heating water.

Increasingly, they are being built when dams and turbines are installed across the mouths of reservoirs, which are driven by ebbs and flows, respectively, electricity is obtained.

Burning garbage, we get energy

Another method that is already being used in Japan is to create waste incinerators. Today they are built in England, Italy, Denmark, Germany, France, the Netherlands and the USA, but only in Japan these enterprises began to be used not only for their intended purpose, but also for generating electricity. At local factories, 2/3 of all garbage is burned, while the factories are equipped with steam turbines. Accordingly, they supply heat and electricity to nearby areas. At the same time, in terms of costs, building such an enterprise is much more profitable than building a thermal power plant.

More tempting is the prospect of using the Earth's heat where volcanoes are concentrated. In this case, it will not be necessary to drill the Earth too deeply, since already at a depth of 300-500 meters the temperature will be at least twice as high as the boiling point of water.

There is also such a way to generate electricity, as Hydrogen - the simplest and lightest chemical element - can be considered an ideal fuel, because it is where there is water. If you burn hydrogen, you can get water, which decomposes into oxygen and hydrogen. The hydrogen flame itself is harmless, that is, there will be no harm to the environment. The peculiarity of this element is that it has a high calorific value.

What's in the future?

Of course, the energy of the Earth's magnetic field or that which is obtained at nuclear power plants cannot fully satisfy all the needs of mankind, which are growing every year. However, experts say that there is no reason to worry, because fuel resources the planet is enough. Moreover, more and more new sources are being used, environmentally friendly and renewable.

The problem of environmental pollution remains, and it is growing catastrophically fast. Quantity harmful emissions goes off scale, respectively, the air we breathe is harmful, the water has dangerous impurities, and the soil is gradually depleted. That is why it is so important to timely study such a phenomenon as energy in the bowels of the Earth in order to look for ways to reduce the need for fossil fuels and make more active use of non-traditional energy sources.

Doctor of technical sciences ON THE. I swear, professor,
Academician of the Russian Academy of Technological Sciences, Moscow

In recent decades, the world is considering the direction of more effective use energy of the deep heat of the Earth with the aim of partial replacement of natural gas, oil, coal. This will become possible not only in areas with high geothermal parameters, but also in any area of ​​the globe when drilling injection and production wells and creating circulation systems between them.

The growing interest in recent decades in alternative sources energy is caused by the depletion of hydrocarbon fuel reserves and the need to solve a number of environmental problems. Objective factors (reserves of fossil fuels and uranium, as well as changes in the environment caused by traditional fire and nuclear power) allow us to assert that the transition to new methods and forms of energy production is inevitable.

The world economy is currently heading towards the transition to a rational combination of traditional and new energy sources. The heat of the Earth occupies one of the first places among them.

Geothermal energy resources are divided into hydrogeological and petrogeothermal. The first of them are represented by heat carriers (comprising only 1% of the total geothermal energy resources) - groundwater, steam and steam-water mixtures. The second are geothermal energy contained in hot rocks.

The fountain technology (self-spill) used in our country and abroad for the extraction of natural steam and geothermal waters is simple, but inefficient. With a low flow rate of self-flowing wells, their heat production can recoup the cost of drilling only at a small depth of geothermal reservoirs with high temperature in areas of thermal anomalies. The service life of such wells in many countries does not even reach 10 years.

At the same time, experience confirms that in the presence of shallow collectors of natural steam, the construction of a Geothermal power plant is the most profitable option for using geothermal energy. The operation of such GeoTPPs has shown their competitiveness in comparison with other types of power plants. Therefore, the use of reserves of geothermal waters and steam hydrotherms in our country on the Kamchatka Peninsula and on the islands of the Kuril chain, in the regions North Caucasus, and also possibly in other areas expediently and in a timely manner. But steam deposits are a rarity, its known and predicted reserves are small. Much more common deposits of heat and power water are not always located close enough to the consumer - the heat supply object. This excludes the possibility of large scales of their effective use.

Often in difficult problem outgrow the issues of combating salinity. The use of geothermal, as a rule, mineralized sources as a heat carrier leads to overgrowth of borehole zones with iron oxide, calcium carbonate and silicate formations. In addition, the problems of erosion-corrosion and scaling adversely affect the operation of the equipment. The problem, also, is the discharge of mineralized and wastewater containing toxic impurities. Therefore, the simplest fountain technology cannot serve as the basis for the widespread development of geothermal resources.

According to preliminary estimates on the territory of the Russian Federation, the predicted reserves of thermal waters with a temperature of 40-250 °C, salinity of 35-200 g/l and a depth of up to 3000 m are 21-22 million m3/day, which is equivalent to burning 30-40 million tons of .t. in year.

The predicted reserves of the steam-air mixture with a temperature of 150-250 ° C of the Kamchatka Peninsula and Kuril Islands is 500 thousand m3/day. and reserves of thermal waters with a temperature of 40-100 ° C - 150 thousand m3 / day.

The reserves of thermal waters with a flow rate of about 8 million m3/day, with a salinity of up to 10 g/l and a temperature above 50 °C are considered top priority for development.

Much greater value for the energy of the future is the extraction of thermal energy, practically inexhaustible petrogeothermal resources. This geothermal energy, enclosed in solid hot rocks, is 99% of the total resources of underground thermal energy. At a depth of up to 4-6 km, massifs with a temperature of 300-400 °C can be found only near the intermediate chambers of some volcanoes, but hot rocks with a temperature of 100-150 °C are distributed almost everywhere at these depths, and with a temperature of 180-200 °C in a fairly significant part territory of Russia.

For billions of years, nuclear, gravitational and other processes inside the Earth have generated and continue to generate thermal energy. Some of it is radiated into outer space, and heat is accumulated in the depths, i.e. heat content of solid, liquid and gaseous phases terrestrial matter and is called geothermal energy.

The continuous generation of intraterrestrial heat compensates for its external losses, serves as a source of accumulation of geothermal energy and determines the renewable part of its resources. The total removal of heat from the interior to the earth's surface is three times higher than the current capacity of power plants in the world and is estimated at 30 TW.

However, it is clear that renewability matters only for limited natural resources, and the total potential of geothermal energy is practically inexhaustible, since it should be defined as the total amount of heat available to the Earth.

It is no coincidence that in recent decades, the world has been considering the direction of more efficient use of the energy of the deep heat of the Earth in order to partially replace natural gas, oil, and coal. This will become possible not only in areas with high geothermal parameters, but also in any area of ​​the globe when drilling injection and production wells and creating circulation systems between them.

Of course, with low thermal conductivity of rocks for effective work circulating systems, it is necessary to have or create a sufficiently developed heat exchange surface in the heat extraction zone. Such a surface is possessed by porous layers and zones of natural fracture resistance, which are often found at the above depths, the permeability of which makes it possible to organize forced filtration of the coolant with efficient extraction of rock energy, as well as artificial creation extensive heat exchange surface in low permeable porous masses by hydraulic fracturing (see figure).

At present, hydraulic fracturing is used in oil and gas industry as a way to increase reservoir permeability to enhance oil recovery during development oil fields. Modern technology makes it possible to create a narrow but long crack, or a short but wide one. Examples of hydraulic fractures with fractures up to 2-3 km long are known.

The domestic idea of ​​extracting the main geothermal resources contained in solid rocks was expressed as early as 1914 by K.E. Obruchev.

In 1963, the first GCC was created in Paris to extract heat from porous formation rocks for heating and air conditioning in the premises of the Broadcasting Chaos complex. In 1985, 64 GCCs were already operating in France with a total thermal capacity of 450 MW, with an annual saving of approximately 150,000 tons of oil. In the same year, the first such GCC was created in the USSR in the Khankala valley near the city of Grozny.

In 1977, according to the project of the Los Alamos National Laboratory of the USA, tests of an experimental GCC with hydraulic fracturing of an almost impermeable massif began at the Fenton Hill site in the state of New Mexico. Injected through the well (injection) cold fresh water was heated due to heat exchange with a rock mass (185 °C) in a vertical fracture with an area of ​​8000 m2, formed by hydraulic fracturing at a depth of 2.7 km. In another well (production), also crossing this crack, superheated water came to the surface in the form of a steam jet. When circulating in a closed circuit under pressure, the temperature of superheated water on the surface reached 160-180 °C, and the thermal power of the system - 4-5 MW. Coolant leaks into the surrounding massif amounted to about 1% of the total flow. The concentration of mechanical and chemical impurities(up to 0.2 g / l) corresponded to the conditions of fresh drinking water. The hydraulic fracture did not require fixing and was kept open hydrostatic pressure liquids. The free convection developing in it provided effective participation in the heat exchange of almost the entire surface of the outcrop of a hot rock mass.

The extraction of underground thermal energy from hot impermeable rocks, based on the methods of inclined drilling and hydraulic fracturing that have been mastered and practiced in the oil and gas industry for a long time, did not cause seismic activity or any other harmful effects on the environment.

In 1983, British scientists repeated the American experience by creating an experimental GCC with hydraulic fracturing of granites in Carnwell. Similar works were held in Germany, Sweden. More than 224 geothermal heating projects have been implemented in the USA. It is assumed, however, that geothermal resources can provide the bulk of the US's future non-electric thermal energy needs. In Japan, the capacity of GeoTPP in 2000 reached approximately 50 GW.

Currently, research and exploration of geothermal resources is carried out in 65 countries. In the world, based on geothermal energy, stations with a total capacity of about 10 GW have been created. The United Nations is actively supporting the development of geothermal energy.

The experience accumulated in many countries of the world in the use of geothermal coolants shows that in favorable conditions they turn out to be 2-5 times more profitable than thermal and nuclear power plants. Calculations show that one geothermal well can replace 158 thousand tons of coal per year.

Thus, the Earth's heat is perhaps the only major renewable energy resource, the rational development of which promises to reduce the cost of energy compared to modern fuel energy. With an equally inexhaustible energy potential, solar and thermonuclear installations, unfortunately, will be more expensive than existing fuel.

Despite the very long history of the development of the Earth's heat, today geothermal technology has not yet reached its high development. The development of the thermal energy of the Earth is experiencing great difficulties in construction deep wells, which are a channel for bringing the coolant to the surface. Due to the high bottomhole temperature (200-250 °C), traditional rock cutting tools are unsuitable for working in such conditions, there are special requirements for the selection of drill and casing pipes, cement slurries, drilling technology, well casing and completion. Domestic measuring equipment, serial operational fittings and equipment are produced in a design that allows temperatures not higher than 150-200 ° C. Traditional deep mechanical drilling of wells is sometimes delayed for years and requires significant financial costs. In the main production assets, the cost of wells is from 70 to 90%. This problem can and should be solved only by creating a progressive technology for the development of the main part of geothermal resources, i.e. extraction of energy from hot rocks.

Our group of Russian scientists and specialists has been dealing with the problem of extracting and using the inexhaustible, renewable deep thermal energy of the Earth's hot rocks on the territory of the Russian Federation for more than one year. The purpose of the work is to create on the basis of domestic, high technology technical means for deep penetration into the bowels of the earth's crust. Currently, several variants of drilling tools (BS) have been developed, which have no analogues in world practice.

The work of the first version of the BS is linked to the current traditional technology well drilling. Hard rock drilling speed ( average density 2500-3300 kg/m3) up to 30 m/h, well diameter 200-500 mm. The second variant of the BS performs drilling of wells in an autonomous and automatic mode. The launch is carried out from a special launch and acceptance platform, from which its movement is controlled. One thousand meters of BS in hard rocks will be able to pass within a few hours. Well diameter from 500 to 1000 mm. Reusable BS options have a large economic efficiency and huge potential value. The introduction of BS into production will open a new stage in the construction of wells and provide access to inexhaustible sources of thermal energy of the Earth.

For the needs of heat supply, the required depth of wells throughout the country lies in the range of up to 3-4.5 thousand meters and does not exceed 5-6 thousand meters. The temperature of the heat carrier for housing and communal heat supply does not go beyond 150 °C. For industrial facilities, the temperature, as a rule, does not exceed 180-200 °C.

The purpose of creating the GCC is to provide constant, affordable, cheap heat to remote, hard-to-reach and undeveloped regions of the Russian Federation. The duration of operation of the GCS is 25-30 years or more. Payback period of stations (taking into account the latest technologies drilling) - 3-4 years.

The creation in the Russian Federation in the coming years of appropriate capacities for the use of geothermal energy for non-electric needs will replace about 600 million tons of equivalent fuel. Savings can be up to 2 trillion rubles.

Until 2030, it becomes possible to create energy capacities to replace fire energy by up to 30%, and until 2040 to almost completely eliminate organic raw materials as fuel from the energy balance of the Russian Federation.

Literature

1. Goncharov S.A. Thermodynamics. Moscow: MGTUim. N.E. Bauman, 2002. 440 p.

2. Dyadkin Yu.D. etc. Geothermal thermal physics. St. Petersburg: Nauka, 1993. 255 p.

3. Mineral resource base fuel and energy complex of Russia. Status and prognosis / V.K. Branchhugov, E.A. Gavrilov, V.S. Litvinenko and others. Ed. V.Z. Garipova, E.A. Kozlovsky. M. 2004. 548 p.

4. Novikov G. P. et al. Drilling wells for thermal waters. M.: Nedra, 1986. 229 p.