Abstract production, transmission and use of electrical energy. Production, transmission and distribution of electrical energy

Electric power systemcalled the electrical part of the energy system and those powered by it, united by the commonality of the process of production, transmission, distribution and consumption electrical energy.

Currently, 74 regional systems operate in parallel within 6 integrated energy systems.

Electric power network is a set of electrical installations for the transmission and distribution of electrical energy, consisting of substations, switchgears, conductors, overhead and cable power lines operating in a certain territory.

A substation is an electrical installation that serves for the conversion and distribution of electricity and consists of transformers or other energy converters, switchgear up to and above 1000 V, a battery of control devices and auxiliary structures.

Distribution device is an electrical installation that serves to receive and distribute electricity and contains switching devices, busbars and connecting busbars, auxiliary devices (compressor, battery, etc.), as well as protection devices, automation and measuring instruments.

Power transmission line (PTL) any voltage (overhead or cable) is an electrical installation designed to transmit electrical energy at the same voltage without transformation.

Rice. 1. Transmission and distribution of electrical energy

Based on a number of characteristics, electrical networks are divided into a large number of varieties for which they are used various methods calculation, installation and operation.

Electrical networks are divided:

4. compliance with the technology of electrical installation work;

5. timely and high-quality implementation of technical operation rules.

Electrical network survivability- this is the ability to fulfill its purpose under conditions of destructive influences, including in a combat situation under the influence of enemy weapons.

Vitality is achieved:

1. using structures that are least susceptible to destruction when exposed to damaging factors of enemy weapons;

2. special protection of the network from damaging factors;

3. clear organization of repair and restoration work. Survivability is a basic tactical requirement.

Cost-effectiveness is the minimum cost of constructing and operating a network, subject to the requirements of reliability and survivability.

Cost-effectiveness is ensured by:

1. using typical commercially produced and standard designs;

2. unification of materials and equipment;

3. the use of non-scarce and inexpensive materials;

4. opportunity further development, expansions and improvements during operation.

I. I. Meshcheryakov

Production (generation), distribution and consumption of electrical and thermal energy: a power plant produces (or generates) electrical energy, and a heating power plant produces electrical and thermal energy. Based on the type of primary energy source converted into electrical or thermal energy, power plants are divided into thermal (CHP), nuclear (NPP) and hydraulic (HPP). At thermal power plants, the primary source of energy is organic fuel (coal, gas, oil), at nuclear power plants - uranium concentrate, at hydroelectric power plants - water (hydraulic resources). Thermal power plants are divided into condensing thermal power plants (condensing power stations - CES or state district power plants - GRES), which generate only electricity, and heating plants (CHP), which generate both electricity and heat.

In addition to thermal power plants, nuclear power plants and hydroelectric power plants, there are other types of power plants (pumped storage, diesel, solar, geothermal, tidal and wind power plants). However, their power is low.

The electrical part of the power plant includes a variety of main and auxiliary equipment. The main equipment intended for the production and distribution of electricity includes: synchronous generators that generate electricity (at thermal power plants - turbogenerators); busbars designed to receive electricity from generators and distribute it to consumers; switching devices - switches designed to turn on and off circuits in normal and emergency conditions, and disconnectors designed to remove voltage from de-energized parts of electrical installations and to create a visible break in the circuit (disconnectors, as a rule, are not designed to break the operating current of the installation); electrical receivers for own needs (pumps, fans, emergency electric lighting, etc.). Auxiliary equipment is designed to perform measurement, alarm, protection and automation functions, etc.

Energy system (power system) consists of power plants, electrical networks and electricity consumers, interconnected and connected by a common mode in the continuous process of production, distribution and consumption of electrical and thermal energy, with general management of this mode.

Electrical power (electrical) system- this is a set of electrical parts of power plants, electrical networks and electricity consumers, connected by the commonality of the regime and the continuity of the process of production, distribution and consumption of electricity. The electrical system is part of the energy system, with the exception of heating networks and heat consumers. An electrical network is a set of electrical installations for the distribution of electrical energy, consisting of substations, switchgears, overhead and cable power lines. The electrical network distributes electricity from power plants to consumers. Power transmission line (overhead or cable) is an electrical installation designed to transmit electricity.

In our country, we use standard rated (phase-to-phase) voltages of three-phase current with a frequency of 50 Hz in the range of 6-1150 kV, as well as voltages of 0.66; 0.38 (0.22) kV.

The transmission of electricity from power plants via power lines is carried out at voltages of 110-1150 kV, i.e. significantly exceeding the voltage of generators. Electrical substations are used to convert electricity of one voltage into electricity of another voltage. An electrical substation is an electrical installation designed to convert and distribute electrical energy. Substations consist of transformers, busbars and switching devices, as well as auxiliary equipment: relay protection and automation devices, measuring instruments. Substations are designed to connect generators and consumers with power lines (step-up and step-down substations P1 and P2), as well as to connect individual parts of the electrical system.

It is difficult to overestimate the importance of electricity. Rather, we subconsciously underestimate it. After all, almost all the equipment around us runs on electricity. There is no need to talk about basic lighting. But we are practically not interested in electricity production. Where does electricity come from and how is it stored (and in general, is it possible to save)? How much does it actually cost to generate electricity? And how safe is it for the environment?

Economic significance

We know from school that power supply is one of the main factors in achieving high labor productivity. Electric power is the core of all human activity. There is not a single industry that can do without it.

The development of this industry indicates the high competitiveness of the state, characterizes the growth rate of production of goods and services, and almost always turns out to be a problematic sector of the economy. The cost of generating electricity often consists of a significant initial investment that will be recouped long years. Despite all its resources, Russia is no exception. After all, energy-intensive industries make up a significant share of the economy.

Statistics tell us that in 2014, Russia's electricity production has not yet reached the Soviet level of 1990. Compared to China and the USA, the Russian Federation produces - respectively - 5 and 4 times less electricity. Why is this happening? Experts say that this is obvious: the highest non-production costs.

Who consumes electricity

Of course, the answer is obvious: every person. But now we are interested in industrial scales, which means those industries that primarily need electricity. The main share falls on industry – about 36%; Fuel and energy complex (18%) and the residential sector (slightly more than 15%). The remaining 31% of electricity generated comes from non-manufacturing sectors, railway transport and losses in networks.

It should be taken into account that the consumption structure varies significantly depending on the region. Thus, in Siberia, more than 60% of electricity is actually used by industry and the fuel and energy complex. But in the European part of the country, where a larger number of settlements, the most powerful consumer is the residential sector.

Power plants are the backbone of the industry

Electricity production in Russia is provided by almost 600 power plants. The power of each exceeds 5 MW. The total capacity of all power plants is 218 GW. How do we get electricity? The following types of power plants are used in Russia:

• thermal (their share in total production is about 68.5%);
• hydraulic (20.3%);
• atomic (almost 11%);
• alternative (0.2%).

When it comes to alternative sources electricity, romantic pictures with windmills and solar panels come to mind. However, in certain conditions and locations these are the most profitable types of electricity generation.

Thermal power plants

Historically, thermal power plants (TPPs) occupy the main place in production process. On the territory of Russia, thermal power plants providing electricity production are classified according to the following criteria:

• energy source – fossil fuel, geothermal or solar energy;
• type of generated energy – heating, condensation.

Another important indicator is the degree of participation in covering the electrical load schedule. Here we highlight basic thermal power plants with a minimum time of use per year of 5000 hours; semi-peak (they are also called maneuverable) - 3000-4000 hours per year; peak (used only during maximum load) – 1500-2000 hours per year.

Technology for producing energy from fuel

Of course, mainly the production, transmission and use of electricity by consumers occurs through thermal power plants running on fossil fuels. They are distinguished by production technology:

• steam turbine;
• diesel;
• gas turbine;
• steam-gas.

Steam turbine units are the most common. They operate on all types of fuel, including not only coal and gas, but also fuel oil, peat, shale, firewood and wood waste, as well as processed products.

Organic fuel

The largest volume of electricity production occurs at Surgut State District Power Plant-2, the most powerful not only in the Russian Federation, but also on the entire Eurasian continent. Running on natural gas, it produces up to 5,600 MW of electricity. And of the coal-fired ones, the Reftinskaya GRES has the largest power – 3800 MW. More than 3000 MW can also be provided by Kostroma and Surgutskaya GRES-1. It should be noted that the abbreviation GRES has not changed since Soviet Union. It stands for State District Power Plant.

During the reform of the industry, the production and distribution of electricity at thermal power plants must be accompanied by the technical re-equipment of existing stations and their reconstruction. Also among the priority tasks is the construction of new energy generating capacities.

Electricity from renewable resources

Electricity obtained with the help of hydroelectric power stations is an essential element of the stability of the unified energy system of the state. It is hydroelectric power plants that can increase the volume of electricity production in a matter of hours.

The great potential of Russian hydropower lies in the fact that almost 9% of the world's water reserves are located on the country's territory. This is the second place in the world in terms of the availability of hydro resources. Countries such as Brazil, Canada and the United States have been left behind. The production of electricity in the world through hydroelectric power plants is somewhat complicated by the fact that the most favorable places for their construction are significantly removed from populated areas or industrial enterprises.

Nevertheless, thanks to the electricity produced at hydroelectric power stations, the country manages to save about 50 million tons of fuel. If it were possible to harness the full potential of hydropower, Russia could save up to 250 million tons. And this is already a serious investment in the country’s ecology and the flexible capacity of the energy system.

Hydroelectric power stations

The construction of hydroelectric power stations solves many issues not related to energy production. This includes the creation of water supply and sanitation systems for entire regions, and the construction of irrigation networks, which are so necessary for agriculture, and flood control, etc. The latter, by the way, is of no small importance for the safety of people.

The production, transmission and distribution of electricity is currently carried out by 102 hydroelectric power stations, the unit capacity of which exceeds 100 MW. The total capacity of Russian hydraulic installations is approaching 46 GW.

Electricity producing countries regularly compile their rankings. So, Russia now ranks 5th in the world in generating electricity from renewable resources. The most significant objects should be considered the Zeya hydroelectric power station (it is not only the first of those built in the Far East, but also quite powerful - 1330 MW), the Volga-Kama cascade of power plants (the total production and transmission of electricity is more than 10.5 GW), the Bureyskaya hydroelectric power station ( 2010 MW), etc. I would also like to mention the Caucasian hydroelectric power stations. Of the several dozen operating in this region, the new (already commissioned) Kashkhatau hydroelectric power station with a capacity of more than 65 MW stands out the most.

The geothermal hydroelectric power stations of Kamchatka also deserve special attention. These are very powerful and mobile stations.

The most powerful hydroelectric power stations

As already noted, the production and use of electricity is hampered by the remoteness of the main consumers. However, the state is busy developing this industry. Not only are existing hydroelectric power stations being reconstructed, but new ones are also being built. They must master mountain rivers Caucasus, high-water Ural rivers, as well as resources Kola Peninsula and Kamchatka. Among the most powerful, we note several hydroelectric power stations.

Sayano-Shushenskaya named after. PS Neporozhniy was built in 1985 on the Yenisei River. Its current capacity has not yet reached the estimated 6000 MW due to reconstruction and repairs after the 2009 accident.

The production and consumption of electricity at the Krasnoyarsk hydroelectric power station is designed for the Krasnoyarsk aluminum smelter. This is the only “client” of the hydroelectric power station, which was commissioned in 1972. Its design capacity is 6000 MW. The Krasnoyarsk hydroelectric power station is the only one on which a ship lift is installed. It ensures regular navigation on the Yenisei River.

The Bratsk hydroelectric power station was put into operation back in 1967. Its dam blocks the Angara River near the city of Bratsk. Like the Krasnoyarsk hydroelectric power station, the Bratsk hydroelectric station serves the needs of the Bratsk aluminum smelter. All 4,500 MW of electricity goes to him. And the poet Yevtushenko dedicated a poem to this hydroelectric station.

Another hydroelectric power station is located on the Angara River - Ust-Ilimskaya (with a capacity of just over 3800 MW). Its construction began in 1963 and ended in 1979. At the same time, the production of cheap electricity began for the main consumers: the Irkutsk and Bratsk aluminum smelters, the Irkutsk aircraft building plant.

The Volzhskaya hydroelectric power station is located north of Volgograd. Its capacity is almost 2600 MW. This largest hydroelectric power station in Europe has been in operation since 1961. Not far from Tolyatti, the oldest of the large hydroelectric power stations, Zhigulevskaya, operates. It was put into operation back in 1957. The power of the hydroelectric power station is 2330 MW and covers the electricity needs of the Central part of Russia, the Urals and the Middle Volga.

Here's what you need for your needs Far East Electricity production is provided by the Bureyskaya HPP. We can say that it is still very “young” - commissioning took place only in 2002. The installed capacity of this hydroelectric power station is 2010 MW of electricity.

Experimental offshore hydropower plants

Numerous oceanic and sea bays also have hydroelectric potential. After all, the height difference during high tide in most of them exceeds 10 meters. This means that it is possible to develop great amount energy. In 1968, the Kislogubskaya experimental tidal station was opened. Its power is 1.7 MW.

Peaceful atom

Russian nuclear energy is a full cycle technology: from the extraction of uranium ores to the production of electricity. Today, the country has 33 power units at 10 nuclear power plants. The total installed capacity is just over 23 MW.

The maximum amount of electricity generated by the nuclear power plant was in 2011. The figure was 173 billion kWh. Per capita electricity production from nuclear power plants increased by 1.5% compared to the previous year.

Certainly, priority direction The development of nuclear energy is operational safety. But also in the fight against global warming Nuclear power plants play a significant role. Environmentalists constantly talk about this, emphasizing that only Russia is able to reduce emissions. carbon dioxide into the atmosphere by 210 million tons per year.

Nuclear energy developed mainly in the North-West and in the European part of Russia. In 2012, all nuclear power plants generated about 17% of all electricity produced.

Nuclear power plants in Russia

The largest nuclear power plant in Russia is located in Saratov region. The annual capacity of the Balakovo NPP is 30 billion kW/h of electricity. At the Beloyarsk NPP (Sverdlovsk region), only the 3rd unit is currently operating. But this allows us to call it one of the most powerful. 600 MW of electricity is obtained thanks to a fast neutron reactor. It is worth noting that this was the world's first fast neutron power unit installed to produce electricity on an industrial scale.

The Bilibino Nuclear Power Plant is installed in Chukotka, which produces 12 MW of electricity. And the Kalinin NPP can be considered recently built. Its first unit was put into operation in 1984, and the last (fourth) only in 2010. The total capacity of all power units is 1000 MW. In 2001, the Rostov NPP was built and put into operation. Since the connection of the second power unit - in 2010 - its installed capacity has exceeded 1000 MW, and the capacity utilization factor was 92.4%.

Wind energy

The economic potential of Russian wind energy is estimated at 260 billion kWh per year. This is almost 30% of all electricity produced today. The capacity of all wind turbines operating in the country is 16.5 MW of energy.

Particularly favorable for the development of this industry are such regions as the ocean coasts, foothills and mountainous regions of the Urals and the Caucasus.

Technological schemes and environmental indicators of electricity production at thermal and nuclear power plants, heating plants and wind power plants. Modern tendencies development of the electric power industry.

Electric power industry- the energy sector, which includes the production, transmission and sale of electricity. Electric power is the most important branch of energy, which is explained by the advantages of electricity over other types of energy, such as the relative ease of transmission over long distances, distribution between consumers, as well as conversion into other types of energy (mechanical, thermal, chemical, light, etc.). Distinctive feature Electric energy is the practical simultaneity of its generation and consumption, since electric current propagates through networks at a speed close to the speed of light.

Historical excursion: Electric Energy for a long time was only an object of experimentation and had no practical application. The first attempts at the beneficial use of electricity were made in the second half of the 19th century, the main areas of use were the recently invented telegraph, electroplating, and the military. At first, galvanic cells served as sources of electricity. A significant breakthrough in the mass distribution of electricity was the invention of electric machine sources of electrical energy - generators. Compared to galvanic cells, generators had greater power and useful life, were significantly cheaper and made it possible to arbitrarily set the parameters of the generated current. It was with the advent of generators that the first power stations and networks began to appear - the electric power industry became a separate industry. The first power transmission line in history (in the modern sense) was the Laufen - Frankfurt line, which began operation in 1891. The length of the line was 170 km, voltage 28.3 kV, transmitted power 220 kW. An important stage was the invention of the electric tram: tram systems were large consumers of electrical energy and stimulated the increase in the capacity of electrical stations. In many cities, the first electrical stations were built along with tram systems.

The beginning of the 20th century was marked by the so-called “war of currents” - a confrontation between industrial manufacturers of direct and alternating currents. Direct and alternating current had both advantages and disadvantages in use. The decisive factor was the possibility of transmission over long distances - the transmission of alternating current was implemented more easily and cheaper, which determined its victory in this “war”: at present, alternating current is used almost everywhere. However, there are currently prospects for the widespread use of direct current for long-distance transmission of high power.

Electrical energy transmission and distribution

The transmission of electrical energy from power plants to consumers is carried out via electrical networks. From a technical point of view, electrical network is a collection of power transmission lines (PTLs) and transformers located at substations.

Power lines They are a metal conductor through which electric current passes. Electricity supply in the vast majority of cases is three-phase, so the power line usually consists of three phases, each of which may include several wires. Structurally, power lines are divided into air And cable.

o Overhead power lines suspended above the ground at a safe height on special structures called supports. The main advantage of overhead power lines is their relative cheapness compared to cable lines. Maintainability is also much better (especially in comparison with brushless cable lines): there is no need to carry out excavation work to replace the wire, and visual inspection of the condition of the line is not difficult. However, overhead power lines have a number of disadvantages: a wide right-of-way - it is prohibited to erect any structures or plant trees in the vicinity of the power lines; insecurity from external influences, for example, trees falling on the line and wire theft. Due to vulnerability, one overhead line is often equipped with two circuits: the main one and the backup one. Aesthetic unattractiveness; This is one of the reasons for the almost universal transition to cable power transmission in the city.

For overhead AC lines, the following scale of voltage classes is adopted: alternating - 0.4, 6, 10, 20, 35, 110, 150, 220, 330, 400, 500, 750, 1150 kV; constant – 400, 800 kV

o Cable lines (CL) are carried out underground. Electrical cables have different design, however, common elements can be identified. The core of the cable is three conductive cores (according to the number of phases). The cables have both external and intercore insulation. Typically, liquid transformer oil or oiled paper acts as an insulator. The conductive core of the cable is usually protected by steel armor. WITH outside The cable is covered with bitumen. The main advantage of cable power lines (compared to overhead lines) is the absence of a wide right-of-way. The disadvantages of cable power lines include the high cost of construction and subsequent operation. Cable lines are less accessible for visual observation.

AC lines.

Most energy is transmitted through alternating current power lines.

AC power lines have a very important advantage: anywhere on the line, a step-down transformer connected to the line transmits energy to consumers.

Disadvantages of AC lines: the presence of inductive reactance of the line, which is associated with the phenomenon electromagnetic induction. Inductive reactance significantly impairs the transmission of electricity in the line, since it leads to a decrease in voltage along the path from the source to the consumer. Line inductance causes a phase shift between current and voltage fluctuations. To reduce inductive reactance, various methods are used: a) for example, they include capacitors in the battery line; b) splitting one wire into several, which leads to a decrease in the inductive reactance of the line.

B) Electricity can be transmitted and via DC power lines.

DC power lines have advantages over AC lines. First of all, when direct current passes, there is no inductive reactance. In addition, lower metal consumption of wires (two wires are used instead of three in three-phase current lines); less losses due to corona discharge, hence less radio interference. Finally, the main thing is that the use of direct current in power lines makes it possible to unusually increase the stability of the power system, which in the case of alternating current requires strict synchronization, constant frequency of all generators included in the overall system. For direct current there is no such problem.

Nuclear power plant (NPP)

Nuclear power plant (NPP)- a set of technical structures designed to generate electrical energy by using the energy released during a controlled nuclear reaction.

Nuclear power plants are classified according to the reactors installed on them:

· Thermal neutron reactors, which use special moderators to increase the likelihood of neutron absorption by the nuclei of fuel atoms

ü Light water reactors

ü Heavy water reactors

• Fast reactors
• Subcritical reactors using external neutron sources
• Fusion reactors

Nuclear power plants can be divided into:

• Nuclear power plants (NPPs) designed to generate only electricity
• Nuclear combined heat and power plants (CHPs), generating both electricity and thermal energy

The figure shows a diagram of the operation of a nuclear power plant with a double-circuit pressurized water power reactor. The energy released in the reactor core is transferred to the primary coolant. Next, the coolant enters the heat exchanger (steam generator), where it heats the secondary circuit water to a boil. The resulting steam enters turbines that rotate electric generators. At the exit of the turbines, the steam enters the condenser, where it is cooled by a large amount of water coming from the reservoir. Or more in simple words Nuclear fuel decays in the reactor; as it disintegrates, thermal energy is released, which boils water; in turn, the resulting steam turns the turbine, which turns the electric generator, which then produces electricity.

The pressure compensator is a rather complex and cumbersome structure that serves to equalize pressure fluctuations in the circuit during reactor operation that arise due to thermal expansion coolant. The pressure in the 1st circuit can reach up to 160 atmospheres (VVER-1000).

In addition to water, molten sodium or gas can also be used as a coolant in various reactors. The use of sodium makes it possible to simplify the design of the reactor core shell (unlike the water circuit, the pressure in the sodium circuit does not exceed atmospheric pressure), and to get rid of the pressure compensator, but it creates its own difficulties associated with the increased chemical activity of this metal.

Total circuits may vary for different reactors, the diagram in the figure is shown for reactors of the VVER type (Water-Water Energy Reactor). Reactors of the RBMK type (High Power Channel Type Reactor) use one water circuit, and BN reactors (Fast Neutron Reactor) use two sodium and one water circuits.

If it is not possible to use a large amount of water for steam condensation, instead of using a reservoir, the water can be cooled in special cooling towers, which due to their size are usually the most visible part of a nuclear power plant.

Advantages of nuclear power plants:

Small volume of fuel used and the possibility of reuse after processing;

• High power: 1000-1600 MW per power unit;
• Low cost of energy, especially thermal energy.
• Possibility of placement in regions located far from large water-energy resources, large coal deposits, in places where opportunities for the use of solar or wind power are limited.
• When a nuclear power plant operates, a certain amount of ionized gas is released into the atmosphere, but a conventional thermal power plant, along with smoke, releases an even larger amount of radiation emissions, due to the natural content of radioactive elements in coal.

Disadvantages of nuclear power plants:

· Irradiated fuel is dangerous and requires complex and expensive reprocessing and storage measures;

· Variable power operation mode is undesirable for reactors operating on thermal neutrons;

· Large capital investments, both specific, per 1 MW of installed capacity for units with a capacity of less than 700-800 MW, and general, necessary for the construction of the station, its infrastructure, as well as in the event of possible liquidation.

Wind power plants

Wind generator(wind electric installation or abbreviated wind turbine) - a device for converting kinetic energy wind to electric.

Wind generators can be divided into two categories: industrial and domestic (for private use). Industrial ones are installed by the state or large energy corporations. As a rule, they are combined into a network, resulting in a wind power plant. Its main difference from traditional ones (thermal, nuclear) is the complete absence of both raw materials and waste. The only important requirement for a wind farm is a high average annual wind level. The power of modern wind generators reaches 6 MW.

1. Foundation

2. Power cabinet including power contactors and control circuits

4. Stairs

5. Rotating mechanism

6. Gondola

7. Electric generator

8. Wind direction and speed tracking system (anemometer)

9. Brake system

10. Transmission

11. Blades

12. System for changing the angle of attack of the blade

13. Rotor cap.

The principle of operation of wind power plants is simple: the wind turns the blades of the windmill, driving the shaft of the electric generator. That, in turn, generates electrical energy. It turns out that wind power plants work like battery-powered toy cars, only the principle of their operation is the opposite. Instead of converting electrical energy into mechanical energy, wind energy is converted into electrical current.

What are the disadvantages of wind power plants?

First of all, their work adversely affects the operation of the television network. Here is an interesting example that can be given in this regard. Several years ago, unusual complaints began to be received from residents of the Orkney Islands (UK). It turned out that during the operation of a wind farm built on one of the hills, such strong interference occurs in the operation of the television network that the image disappears on the television screens. A solution was found in the construction of a powerful television repeater next to the wind turbine, which made it possible to amplify television signals. According to reports, a 0.1 MW wind power plant can cause distortion of television signals up to 0.5 km away.

Another unexpected feature of wind turbines was that they turned out to be a source of fairly intense infrasonic noise, which has an adverse effect on the human body, causing constant depression, severe unreasonable anxiety and discomfort in life. As the experience of operating a large number of wind turbines in the USA has shown, neither animals nor birds can withstand this noise when leaving the area where the station is located, i.e. The territories of the wind station itself and those adjacent to it become unsuitable for human life, animals and birds.

However, the main disadvantage of this type of energy, along with the variability of wind speed, is its low intensity, which requires a large area to accommodate a wind installation. From the calculations carried out by specialists, it follows that the optimal diameter for a wind wheel is 100 m. With such geometric dimensions and energy density per unit area of ​​the wind wheel of 500 W/m2 (wind speed 9.2 m/s), electrical power can be obtained from the wind flow , close to 1 MW. On an area of ​​1 km2, 2-3 installations of the specified power can be placed, taking into account the fact that they should be located one from the other at a distance equal to three of their heights, so as not to interfere with each other and not reduce the efficiency of their work.

Let us assume for assessment that there are 3 installations located on an area of ​​1 km 2, i.e. from 1 km 2 you can remove 3 MW of electrical power. This means that to accommodate a wind station with an electrical capacity of 1000 MW, an area of ​​330 km 2 is needed. If we compare wind and thermal power plants in terms of energy production throughout the year, the resulting value should be increased by at least 2-3 times. For comparison, we point out that the area Kursk NPP with a capacity of 4000 MW together with auxiliary structures, a cooling pond and a residential village is 30 km2, i.e. per 1000 MW of electrical power there are 7.5 km2. In other words, the size of the territory of a wind station per 1000 MW is 2 orders of magnitude larger than the area occupied by a modern nuclear power plant.

Despite this, some scientists believe that large-scale wind energy should be developed. Before the war, more than 8,000 wind turbines operated in our country on collective and state farms alone. In 1930 On the basis of the TsAGI wind engine department, the Central Wind Energy Institute was created, and in 1938 a design bureau for wind energy installations was organized. In the pre-war years and after the war, a fairly large number (approximately 10 thousand units) of various wind turbines were developed and produced. Intensive work on the use of wind energy is being carried out in a number of foreign countries.

So, we can indicate the following advantages and disadvantages of wind energy: no influence on the thermal balance of the Earth’s atmosphere, oxygen consumption, emissions of carbon dioxide and other pollutants, the possibility of conversion into different kinds energy (mechanical, thermal, electrical), but at the same time low energy density per unit area of ​​the wind wheel; unpredictable changes in wind speed during the day and season, requiring backup of a wind station or accumulation of generated energy; negative impact on the habitat of humans and animals, on television communications and routes seasonal migration birds. Domestic and Foreign experience indicates the technical feasibility and feasibility of the construction and operation of low-power wind power plants for remote villages and distant pastures, as well as in the agricultural sector.

Thermal power plants

The most common are thermal power plants (TPPs), which use thermal energy released by burning organic fuel (solid, liquid and gaseous).

Thermal power plants generate about 76% of the electricity produced on our planet. This is due to the presence of fossil fuels in almost all areas of our planet; the possibility of transporting organic fuel from the extraction site to a power plant located near energy consumers; technical progress at thermal power plants, ensuring the construction of thermal power plants with high power; the possibility of using waste heat from the working fluid and supplying it to consumers, in addition to electrical energy, also thermal energy (with steam or hot water), etc.

The diagram shows the classification of thermal power plants using fossil fuels.

A thermal power plant is a complex of equipment and devices that convert fuel energy into electrical and (in general) thermal energy.

Thermal power plants are characterized by great diversity and can be classified according to various criteria.

Based on their purpose and type of energy supplied, power plants are divided into regional and industrial.

District power plants are independent public power plants that serve all types of consumers in the region (industrial enterprises, transport, population, etc.). District condensing power plants, which generate mainly electricity, often retain their historical name - GRES (state district power plants). District power plants that produce electrical and thermal energy (in the form of steam or hot water), are called combined heat and power plants (CHP). As a rule, state district power plants and district thermal power plants have a capacity of more than 1 million kW.

Industrial power plants are power plants that provide thermal and electrical energy to specific manufacturing enterprises or a complex of them, for example a chemical production plant. Often industrial power plants operate on the general electrical network, but are not subordinate to the power system dispatcher.

Based on the type of fuel used, thermal power plants are divided into power plants operating on fossil fuels and nuclear fuel.

Condensing power plants operating on fossil fuels, at a time when there were no nuclear power plants (NPPs), were historically called thermal power plants (TES - thermal power plant). It is in this sense that this term will be used below, although thermal power plants, nuclear power plants, gas turbine power plants (GTPP), and combined cycle power plants (CGPP) are also thermal power plants operating on the principle of converting thermal energy into electrical energy.

Gaseous, liquid and solid fuels are used as organic fuel for thermal power plants. Most thermal power plants in Russia, especially in the European part, consume natural gas as the main fuel, and fuel oil as a backup fuel, using the latter due to its high cost only in extreme cases; Such thermal power plants are called gas-oil power plants.

Based on the type of thermal power plants used at thermal power plants to convert thermal energy into mechanical energy of rotation of the rotors of turbine units, steam turbine, gas turbine and combined cycle power plants are distinguished.

The basis of steam turbine power plants are steam turbine units (STU), which use the most complex, most powerful and extremely advanced energy machine - a steam turbine - to convert thermal energy into mechanical energy. PTU is the main element of thermal power plants, combined heat and power plants and nuclear power plants.

STPs that have condensing turbines as a drive for electric generators and do not use the heat of exhaust steam to supply thermal energy to external consumers are called condensing power plants. STUs equipped with heating turbines and releasing the heat of exhaust steam to industrial or municipal consumers are called combined heat and power plants (CHP).

Gas turbine thermal power plants (GTPPs) are equipped with gas turbine units (GTUs) running on gaseous or, in extreme cases, liquid (diesel) fuel. Currently, in Russia there is one gas turbine power plant (GRES-3 named after Klasson, Elektrogorsk, Moscow region) with a capacity of 600 MW and one gas turbine cogeneration plant (in the city of Elektrostal, Moscow region).

Thermal power plant diagram (coal-fired)

Thermal power plants operate on the following principle: fuel is burned in the furnace of a steam boiler. The heat released during combustion evaporates the water circulating inside the pipes located in the boiler and overheats the resulting steam. The steam, expanding, rotates the turbine, which, in turn, rotates the shaft of the electric generator. The exhaust steam is then condensed; water from the condenser is returned to the boiler through the heater system.

Advantages of TPP:
1. The fuel used is quite cheap.
2. Require less capital investment compared to other power plants.
3. Can be built anywhere regardless of fuel availability. Fuel can be transported to the power plant location by rail or road transport.
4. Occupy a smaller area compared to hydroelectric power plants.
5. The cost of generating electricity is less than that of diesel power plants.

Flaws:
1. They pollute the atmosphere, releasing large amounts of smoke and soot into the air.
2. Higher operating costs compared to hydroelectric power plants.

QUESTIONS:

1. Define the electric power industry.

2. What advantages does electricity have over other types of energy?

3. The invention of what device is associated with the appearance of the first power stations?

4. What, from a technical point of view, is an electrical network?

5. Name the types of power lines in terms of their design features. List their advantages and disadvantages.

6. Draw a diagram of energy transmission along alternating current lines. Advantages and disadvantages of this method of transmission.

7. Draw a diagram of energy transmission along DC lines. What is their advantage over AC lines?

8. Fill out the table:

9. What causes the widespread use of thermal power plants

Related information.

Electricity production plays a huge role in the world these days. She is the core state economy any country. Huge sums of money are invested annually in the production and use of electricity and Scientific research related to this. IN Everyday life We are constantly faced with its action, so modern people must have an idea of ​​the basic processes of its production and consumption.

How do you get electricity?

Electricity is produced from other types of electricity using special devices. For example, from kinetic. For this purpose, a generator is used - a device that converts mechanical work into electrical energy.

Other existing methods of obtaining it are, for example, the conversion of light radiation by photocells or solar battery. Or electricity production by chemical reaction. Or use the potential radioactive decay or coolant.

It is produced at power plants, which can be hydraulic, nuclear, thermal, solar, wind, geothermal, etc. Basically, they all work according to the same scheme - thanks to the energy of the primary carrier, a certain device generates mechanical (rotation energy), which is then transferred to a special generator, where electric current is generated.

Main types of power plants

The production and distribution of electricity in most countries is carried out through the construction and operation of thermal power plants - thermal power plants. Their operation requires a large supply of organic fuel, the conditions for its extraction are becoming more complicated from year to year, and the cost is increasing. The fuel efficiency coefficient in thermal power plants is not too high (within 40%), and the amount of environmentally polluting waste is large.

All these factors reduce the prospects of this production method.

The most economical production of electricity is from hydropower plants (HPP). Their efficiency reaches 93%, the cost of 1 kW/h is five times cheaper than other methods. Natural spring The energy of such stations is practically inexhaustible, the number of workers is minimal, and they are easy to manage. Our country is a recognized leader in the development of this industry.

Unfortunately, the pace of development is limited by the serious costs and long construction times of hydroelectric power stations associated with their remoteness from large cities and highways, the seasonal regime of rivers and difficult operating conditions.

In addition, giant reservoirs worsen environmental situation- valuable lands around water bodies are flooded.

Use of nuclear energy

Today, the production, transmission and use of electricity are carried out nuclear power plants- NPP. They are designed on almost the same principle as thermal ones.

Their main advantage is the small amount of fuel required. A kilogram of enriched uranium is equivalent in productivity to 2.5 thousand tons of coal. That is why nuclear power plants can theoretically be built in any area, regardless of the availability of nearby fuel resources.

Currently, uranium reserves on the planet are significantly greater than mineral fuel, and the impact of nuclear power plants on surrounding nature minimal, subject to trouble-free operation.

A huge and serious drawback of nuclear power plants is the likelihood of a terrible accident with unpredictable consequences, which is why very serious safety measures are required for their uninterrupted operation. In addition, the production of electricity at nuclear power plants is difficult to regulate - it will take several weeks both to start them and to completely stop them. And there are practically no technologies for recycling hazardous waste.

What is an electric generator

The production and transmission of electricity is possible thanks to an electric generator. This is a device for converting any type of energy (thermal, mechanical, chemical) into electrical energy. The principle of its operation is based on the process of electromagnetic induction. EMF is induced in a conductor that moves in a magnetic field and crosses its force magnetic lines. Thus, the conductor can serve as a source of electricity.

The basis of any generator is a system of electromagnets that form a magnetic field and conductors that cross it. Most of all alternating current generators are based on the use of rotating magnetic field. Its stationary part is called the stator, and the moving part is called the rotor.

Transformer concept

A transformer is an electromagnetic static device designed to convert one current system to another (secondary) using electromagnetic induction.

The first transformers in 1876 were proposed by P. N. Yablochkov. In 1885, Hungarian scientists developed industrial single-phase devices. In 1889-1891. The three-phase transformer was invented.

The simplest single-phase transformer consists of a steel core and a pair of windings. They are used for the distribution and transmission of electricity, because power station generators produce it at voltages from 6 to 24 kW. It is profitable to transmit it at large values ​​(from 110 to 750 kW). For this purpose, step-up transformers are installed at power plants.

How is electricity used?

Its lion's share goes to supplying electricity to industrial enterprises. Manufacturing consumes up to 70% of all electricity generated in the country. This figure varies significantly for individual regions depending on climatic conditions and the level of industrial development.

Another expense item is the supply of electric vehicles. Urban, intercity, and industrial electric transport substations operate from EPS power grids using D.C.. For AC transport, step-down substations are used, which also consume power from power plants.

Another sector of electricity consumption is utilities. The consumers here are buildings in residential areas of any settlements. These are houses and apartments, administrative buildings, shops, educational, scientific, cultural, healthcare, Catering etc.

How does electricity transfer occur?

Production, transmission and use of electricity are the three pillars of the industry. Moreover, transferring the received power to consumers is the most difficult task.

It “travels” mainly through power lines - overhead power lines. Although cable lines are beginning to be used more and more often.

Electricity is generated by powerful units of giant power plants, and its consumers are relatively small receivers scattered over a vast territory.

There is a tendency to concentrate power due to the fact that with their increase, the relative costs of constructing power plants, and therefore the cost of the resulting kilowatt-hour, decrease.

Unified energy complex

A number of factors influence the decision to locate a large power plant. These are the type and quantity of resources available, availability of transportation, climatic conditions, inclusion in a unified energy system, etc. Most often, power plants are built far from large centers of energy consumption. The efficiency of its transmission over considerable distances affects successful work a single energy complex over a vast territory.

The production and transmission of electricity must occur with a minimum amount of losses, main reason which is the heating of the wires, i.e., an increase in the internal energy of the conductor. To maintain power transmitted over long distances, it is necessary to proportionally increase the voltage and reduce the current in the wires.

What is a power line

Mathematical calculations show that the amount of heating losses in wires is inversely proportional to the square of the voltage. That is why electricity is transmitted over long distances using power lines - high-voltage power lines. Between their wires the voltage amounts to tens, and sometimes hundreds of thousands of volts.

Power plants located close to each other are combined into a single energy system using power lines. Electricity production in Russia and its transmission are carried out through a centralized energy network, which includes a huge number of power plants. Unified system control guarantees a constant supply of electricity to consumers.

A little history

How was a unified electrical network formed in our country? Let's try to look into the past.

Until 1917, electricity production in Russia was carried out at an insufficient pace. The country lagged behind its developed neighbors, which negatively affected the economy and defense capability.

After October revolution The project for the electrification of Russia was developed by the State Commission for the Electrification of Russia (abbreviated as GOELRO), headed by G. M. Krzhizhanovsky. More than 200 scientists and engineers collaborated with her. Control was carried out personally by V.I. Lenin.

In 1920, the “Electrification Plan of the RSFSR” was prepared, designed for 10-15 years. It included the restoration of the previous energy system and the construction of 30 new power plants equipped with modern turbines and boilers. The main idea of ​​the plan is to use gigantic domestic hydropower resources. It was planned to electrify and radically reconstruct everything National economy. The emphasis was on the growth and development of the country's heavy industry.

The famous GOERLO plan

Since 1947, the USSR has become Europe's first and world's second producer of electricity. It was thanks to the plan that GOELRO was formed in as soon as possible the entire domestic economy. The production and consumption of electricity in the country has reached a qualitatively new level.

Fulfillment of the plan became possible thanks to a combination of several important factors: high level scientific personnel country, the material potential of Russia preserved from pre-revolutionary times, the centralization of political and economic power, the property Russian people believe in the “tops” and implement the proclaimed ideas.

The plan proved the effectiveness of the Soviet system of centralized power and government.

Plan results

In 1935, the adopted program was implemented and exceeded. 40 power plants were built instead of the planned 30, and almost three times more capacity was introduced than was provided for according to the plan. 13 power plants with a capacity of 100 thousand kW each were built. The total capacity of Russian hydroelectric power stations was about 700,000 kW.

During these years they were built largest objects of strategic importance, such as the world famous Dnieper hydroelectric power station. In terms of total indicators, the Unified Soviet Energy System surpassed similar systems of the most developed countries New and Old World. Electricity production in European countries in those years lagged significantly behind the USSR indicators.

Rural development

If before the revolution there was practically no electricity in the villages of Russia (small power plants installed by large landowners do not count), then with the implementation of the GOELRO plan thanks to the use of electricity Agriculture received a new impetus for development. Electric motors appeared in mills, sawmills, and grain cleaning machines, which contributed to the modernization of the industry.

In addition, electricity firmly entered the life of townspeople and villagers, literally tearing “dark Russia” out of the darkness.