Hydroelectric power station operating principle diagram. Hydroelectric power station - what is it? List of the largest hydroelectric power stations in Russia. Based on the height of the pressure flow, hydroelectric power stations are divided into

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Introduction

Electric stations, their types

Hydraulic power stations

A little about the history of hydroelectric power stations

Operating principle and types of hydroelectric power plants

Hydropower in the world

Hydropower of Russia

Accidents and incidents at hydroelectric power stations

Conclusion

Bibliography

Introduction

The energy industry of our days is one of the most frequently discussed areas of the country’s life, because right now it is acquiring increasingly multifaceted economic, technical and even political aspects.

The relevance of the chosen topic of the test work is beyond doubt, if we remember that scientific and technological progress is impossible without the development of energy. And to increase productivity, automation is paramount production processes, replacement of human labor with machine labor. But the vast majority of technical means of mechanization and automation (equipment, instruments, computers) have an electrical basis. Especially wide application electrical energy was received to drive electric motors.

Humanity needs electricity, and the need for it is increasing every year. At the same time, reserves of traditional organic fuels (oil, coal, gas) are finite. Therefore, today it is extremely important to find profitable sources of electricity, and profitable not only from the point of view of cheap fuel, but also from the point of view of simplicity of design, operation, cost of materials necessary for the construction of the station, and their durability. Such a source can be a hydraulic power plant.

This test is aimed at considering the characteristics of this particular type of power plant. Accordingly, the purpose of the work is, first of all, to familiarize ourselves with the current state of affairs in this issue and to identify the pros and cons of using hydro resources to produce energy.

Electric stations, their types

An electric station is a set of installations, equipment and apparatus used directly for the production of electrical energy, as well as the necessary structures and buildings located in a certain area.

Depending on the energy source, there are:

thermal power plants (TPPs) using natural fuel;

hydroelectric power plants (HPPs), using the energy of falling water from dammed rivers;

nuclear power plants (NPPs) using nuclear energy;

other power plants using wind, solar, geothermal and other types of energy.

Our country produces and consumes a huge amount of electricity. It is almost entirely produced by three main types of power plants: thermal, nuclear and hydroelectric power plants.

Hydraulic power stations

Hydroelectric power plants are very efficient sources of energy. The water back-up necessary for this is created by dams that are erected on rivers and canals. For the efficient production of electricity at a hydroelectric power station, two main factors are necessary: a guaranteed supply of water all year round and possibly large slopes of the river; canyon-like terrain types are favorable for hydraulic construction.

Features of hydroelectric power station:

the cost of electricity at Russian hydroelectric power plants is more than two times lower than at thermal power plants;

much less maintenance personnel required;

have a very high efficiency (more than 80%);

hydraulic installations make it possible to reduce transportation and save mineral fuel (approximately 0.4 tons of coal are consumed per 1 kWh);

hydroelectric turbines allow operation in all modes from zero to maximum power and allow you to quickly change power if necessary, acting as a regulator of electricity generation;

The river flow is a renewable source of energy;

significantly less impact on the air environment than other types of power plants;

the construction of hydroelectric power plants is usually more capital-intensive than thermal power plants;

often efficient hydroelectric power plants are located far from consumers;

reservoirs occupy large areas, but since 1963, protective structures began to be used (Kiev Hydroelectric Power Station), which limited the area of the reservoir, and, as a result, limited the area of the flooded surface (fields, meadows, villages);

dams often change the nature of fisheries by blocking the passage of anadromous fish to spawning grounds, but they often favor an increase in fish stocks in the reservoir itself and the implementation of fish farming.

A little about the history of hydroelectric power stations

Hydroelectric energy, as well as the muscular energy of humans and animals, as well as solar energy, has been used for a very long time. Mention of the use of water energy in water mills for grinding grain and blowing air when smelting metal dates back to the end of the 2nd century. BC e. Over the centuries, water wheels have increased in size and efficiency. In the 11th century in England and France there was one mill for every 250 people. At this time, the scope of application of mills expanded. They began to be used in the cloth production, brewing beer, sawing wood, for operating pumps, and in oil mills. Modern hydropower can be considered to have been born in 1891. This year, the Russian engineer Mikhail Osipovich Dolivo-Dobrovolsky, who emigrated to Germany due to “political unreliability,” was supposed to demonstrate the alternating current motor he invented at the electrical exhibition in Frankfurt am Main. This engine, with a power of about 100 kilowatts, in the era of constant electric current itself was supposed to be the highlight of the exhibition, but the inventor decided to build a completely unexpected structure for its power supply at that time - a hydroelectric power station. In the small town of Lauffen, Dolivo-Dobrovolsky installed a three-phase current generator, which was rotated by a small water turbine. Electrical energy was transmitted to the exhibition territory via transmission lines that were incredibly long for those years, 175 kilometers long (nowadays transmission lines thousands of kilometers long do not surprise anyone, but at that time such construction was unanimously recognized as impossible). Just a few years before this event, the most prominent English engineer and physicist Osborne Reynolds, in his Cantor Lectures, seemingly irrefutably proved that when transmitting energy by means of transmission, energy losses are only 1.4% per mile, while when transmitting electric energy losses along wires over the same distance will be 6%. Based on experimental data, he concluded that when using electric current at the other end of the transmission line, it is unlikely that it will be possible to have more than 15-20% of the initial power. At the same time, he believed, you can be sure that when energy is transferred by the drive cable, 90% of the power will be retained. This “indisputable” conclusion was successfully refuted by the work of the first-born hydroelectric power industry in Lauffen.

But the era of hydropower had not yet arrived. The advantages of hydroelectric power plants are obvious - a supply of energy constantly renewed by nature itself, ease of operation, and lack of environmental pollution. And the experience of building and operating water wheels could be of great help to hydropower engineers. However, building a dam for a large hydroelectric power station turned out to be a much more difficult task than building a small dam to turn a mill wheel. To drive powerful hydraulic turbines, you need to accumulate a huge supply of water behind the turbine. To build a dam, it is necessary to lay such a quantity of materials that the volume of gigantic Egyptian pyramids will seem insignificant in comparison. Therefore, at the beginning of the twentieth century, only a few hydroelectric power plants were built. This was just the beginning. The development of hydropower resources was carried out at a rapid pace, and in the 30s of the twentieth century, the implementation of such large projects as the Hoover hydroelectric power station in the USA with a capacity of 1.3 gigowatts was completed. The construction of such powerful hydroelectric power plants caused an increase in energy use in industrialized countries, and this, in turn, gave impetus to programs for the development of large hydropower potentials.

Currently, the use of water energy is still relevant, and the main direction is the production of electricity.

Operating principle and types of hydroelectric power plants

Hydraulic installations are represented by hydroelectric power plants (HPP), pumped storage power plants (PSP) and tidal power plants (TPP). Their placement largely depends on natural conditions, for example, the nature and regime of the river. In mountainous areas, high-pressure hydroelectric power plants are usually built; on lowland rivers, installations with lower pressure but higher water flow are used. Hydraulic construction in plains is more difficult due to the predominance of soft foundations under dams and the need to have large reservoirs to regulate flow. The construction of hydroelectric power stations on the plains causes flooding of adjacent areas, which causes significant material damage.

A hydroelectric power station consists of a sequential chain of hydraulic structures that provide the necessary concentration of water flow and the creation of pressure, and energy equipment that converts the energy of water moving under pressure into mechanical rotational energy, which, in turn, is converted into electrical energy.

The pressure of a hydroelectric power station is created by the concentration of the fall of the river on the site being used by a dam, or diversion, or a dam and diversion together. The main power equipment of the hydroelectric power station is located in the hydroelectric power station building: in the turbine room of the power plant - hydraulic units, auxiliary equipment, automatic control and monitoring devices; in the central control post there is a control panel for the operator-dispatcher or an automatic operator of the hydroelectric power station. The step-up transformer substation is located both inside the hydroelectric power station building and in separate buildings or in open areas. Switchgears are often located in open areas. A hydroelectric power plant building can be divided into sections with one or more units and auxiliary equipment, separated from adjacent parts of the building. An installation site is created at or inside the hydroelectric power station building for the assembly and repair of various equipment and for auxiliary operations for the maintenance of the hydroelectric power station.

Based on installed capacity (in MW), hydroelectric power stations are distinguished between powerful (over 250), medium (up to 25) and small (up to 5). The power of a hydroelectric power station depends on the pressure Nb (the difference between the levels of the upper and lower pools), the water flow Q (m3/sec) used in hydraulic turbines, and the efficiency of the hydraulic unit hg. For a number of reasons (due to, for example, seasonal changes in the water level in reservoirs, fluctuations in the load of the power system, repairs of hydraulic units or hydraulic structures, etc.), the pressure and flow of water continuously change, and in addition, the flow changes when regulating the power of a hydroelectric power station. There are annual, weekly and daily cycles of hydroelectric power station operation.

Based on the maximum used pressure, hydroelectric power stations are divided into high-pressure (more than 60 m), medium-pressure (from 25 to 60 m) and low-pressure (from 3 to 25 m). On lowland rivers, pressures rarely exceed 100 m; in mountainous conditions, pressures of up to 300 m or more can be created using a dam, and with the help of diversion - up to 1500 m. The classification by pressure approximately corresponds to the types of power equipment used: at high-pressure hydroelectric power stations, bucket and radial hydroelectric power plants are used. axial turbines with metal spiral chambers; on medium-pressure ones - rotary-blade and radial-axial turbines with reinforced concrete and metal spiral chambers, on low-pressure ones - rotary-blade turbines in reinforced concrete spiral chambers, sometimes horizontal turbines in capsules or in open chambers. The division of hydroelectric power stations according to the pressure used is of an approximate, conditional nature.

Based on the principle of use of water resources and pressure concentration, hydroelectric power stations are usually divided into run-of-river, dam-based, diversion with pressure and free-flow diversion, mixed, pumped storage and tidal. Run-of-river and dam-side hydroelectric power stations are the most common types of hydroelectric power stations. In such hydroelectric power plants, the water pressure is created by a dam that blocks the river and raises the water level in the upper pool. At the same time, some flooding of the river valley is inevitable. If two dams are built on the same section of the river, the flood area is reduced. On lowland rivers, the largest economically permissible flood area limits the height of the dam. Run-of-river and near-dam hydroelectric power stations are built both on lowland high-water rivers and on mountain rivers, in narrow compressed valleys.

In addition to the dam, the structures of a run-of-the-river hydroelectric power station include the hydroelectric power station building and spillway structures. The composition of hydraulic structures depends on the head height and installed power. At a run-of-the-river hydroelectric power station, the building with the hydraulic units housed in it serves as a continuation of the dam and together with it creates a pressure front. At the same time, the upper pool is adjacent to the hydroelectric power station building on one side, and the lower pool is adjacent to it on the other. The supply spiral chambers of hydraulic turbines with their inlet sections are laid under the level of the upstream, while the outlet sections of the suction pipes are immersed under the level of the downstream.

In accordance with the purpose of the waterworks, it may include shipping locks or a ship lift, fish passage structures, water intake structures for irrigation and water supply. In run-of-the-river hydroelectric power plants, sometimes the only structure that allows water to pass through is the hydroelectric power station building. In these cases, useful water sequentially passes through the inlet section with waste-retaining gratings, a spiral chamber, a hydraulic turbine, and a suction pipe, and the river's flood flows are discharged through special conduits between adjacent turbine chambers. Run-of-river hydroelectric power plants are characterized by pressures of up to 30-40 m; The simplest run-of-river hydroelectric power plants also include previously built small-capacity rural hydroelectric power stations. On large lowland rivers, the main channel is blocked by an earthen dam, adjacent to which is a concrete spillway dam and a hydroelectric power station building is constructed.

Dam hydroelectric power plants are built at higher water pressures. In this case, the river is completely blocked by a dam, and the hydroelectric power station building itself is located behind the dam, in its lower part. Water, in this case, is supplied to the turbines through special pressure tunnels, and not directly, as in run-of-the-river hydroelectric power plants.

Diversion hydroelectric power stations are built in places where the river slope is high. The required water concentration in a hydroelectric power station of this type is created through diversion. Water is drained from the river bed through special drainage systems. The latter are straightened, and their slope is significantly less than the average slope of the river. As a result, water is supplied directly to the hydroelectric power station building. Diversion hydroelectric power plants can be different types- non-pressure or with pressure derivation. In the case of pressure diversion, the water pipeline is laid with a large longitudinal slope. In another case, at the beginning of diversion, a higher dam is created on the river and a reservoir is created - this scheme is also called mixed diversion, since both methods of creating the required water concentration are used.

Pumped storage power plants (PSPPs) are capable of accumulating the generated electricity and putting it into use at times of peak loads. The operating principle of such power plants is as follows: during certain periods (not peak load), pumped storage power plant units operate as pumps from external energy sources and pump water into specially equipped upper pools. When demand arises, water from them enters the pressure pipeline and drives the turbines.

Hydropower in the world

Hydroelectric power currently provides approximately one-fifth of global electricity production. Most of them -

large power plants with a capacity of over 10-15 MW. However, the possibilities for constructing large hydroelectric power plants in Europe have practically been exhausted, and currently attention is directed to the development of small hydroelectric power stations, the capacity of which does not exceed 10 MW (sometimes even a limit of 5 MW is adopted). They generate electricity by converting the energy of small rivers, canals, and industrial watercourses. Today, this technology for generating electricity is technically proven and economically profitable. Continuous improvements in design and control equipment improve the performance of small hydropower plants and facilitate their entry into the clean technology market. A small hydropower plant with an installed capacity of 1 MW can generate 6,000 MWh per year, while preventing the emission of 4,000 tons of carbon dioxide that would be emitted in environment when the same amount of electricity is generated by a coal-fired power plant. The economic potential of hydropower in the world is 7300 TWh/year. Of this volume, 32% has already been developed, including 5% through small hydroelectric power plants. In 1995, 15 EU countries generated 33 TWh/year. By 2010, it was planned to receive 220 TWh/year worldwide from small hydropower in 2010, and the installed capacity was to reach 55 GW. Rapid growth was expected mainly in Asia, Latin America, Central and Eastern Europe and countries of the former Soviet Union. In EU countries, efforts will apparently be focused on the reconstruction of old hydroelectric power stations rather than on the construction of new facilities.

Iceland is the absolute leader in hydropower generation per capita. Apart from this, this figure is highest in Norway, Canada and Sweden. The most active hydraulic construction at the beginning of the 2000s was carried out by China, for which hydropower is the main potential source of energy. This country hosts up to half of the world's small hydroelectric power plants, as well as the world's largest hydroelectric power station, the Three Gorges on the Yangtze River, and the largest cascade of hydroelectric power stations under construction. An even larger hydroelectric power station, the Grand Inga, with a capacity of 39 GW, is planned for construction by an international consortium on the Congo River in the Democratic Republic of the Congo (formerly Zaire).

Benefits and barriers to the development of small hydropower plants

Small hydropower plants have been shown to be the cleanest way to generate energy. Therefore, in the price of the produced kWh, in addition to market price arguments, the factor of minimal impact on the environment must be taken into account. Without taking into account environmental and social factors, the construction of a large gas-fired power plant is often simpler than the restoration and commissioning of a dozen 100 kW small hydroelectric power plants. The most a big problem is that the intentions proclaimed by law are not implemented in practice. Problems also arise at the level of local administrations. Sometimes small local organizations resist the construction of individual large renewable energy projects, without considering the broader benefits of renewable energy.

A typical situation is when the population of a village or a separate area does not receive anything from the installation of a small hydroelectric power station in their area of residence; only the owner of the hydroelectric power station will receive a profit using the local river. Therefore, the new initiative to help these small villages on the part of the small hydropower sector - the abolition of charging for electricity produced by small hydropower plants from residents of those municipalities where the hydroelectric power station was installed - deserves a particularly positive assessment.

Still, small hydropower firms could operate more efficiently. The lack of reliable information disseminated among the local population and weak interaction between firms and local environmental groups are certainly obstacles to the promotion of small hydropower.

Hydropower of Russia

As of 2009, Russia has 15 hydraulic power plants with a capacity of over 1000 MW (operating, under construction, or in frozen construction), and more than a hundred hydroelectric power plants of smaller capacity. Russia has the second largest hydro potential in the world. 852 billion kWh can be produced annually using the energy of Russian rivers, which amounts to 12% of the world's hydro potential.

The most powerful hydroelectric power stations were built on the Volga, Kama, Angara, Yenisei, Ob and Irtysh. A cascade of hydroelectric power plants is a group of hydroelectric power stations located in steps along the flow of water flow with the aim of fully sequentially using its energy. Installations in a cascade are usually connected by a common regime in which the reservoirs of the upper stages have a regulatory influence on the reservoirs of the lower stages. Industrial complexes specializing in energy-intensive industries are being formed on the basis of hydroelectric power stations in the eastern regions.

The most efficient resources in terms of technical and economic indicators are concentrated in Siberia. One example of this is the Angara-Yenisei cascade, which includes the largest hydroelectric power stations in the country: Sayano-Shushenskaya (6.4 million kW), Krasnoyarsk (6 million kW), Bratsk (4.6 million kW), Ust-Ilimskaya (4.3 million kW). The Boguchanovskaya hydroelectric power station (4 million kW) is under construction. The total capacity of the cascade is currently more than 20 million kW. Kargiev V.M. Small hydropower in Russia - current state // Quarterly information bulletin “Renewable Energy”. - April, 2002. - p. 4-8

Hydropower occupies an important place in Russia's energy balance. Currently, about 20% (165 billion kWh) of the country's electricity is produced at hydroelectric power plants, with the total installed capacity of hydroelectric power stations in Russia being 44.1 GW. A significant part of the untapped potential is located in energy-scarce regions such as the North Caucasus and the Far East.

Despite the fact that the potential for the development of hydropower in Russia is great, intensive construction of hydroelectric power stations is not expected in the near future, which is due to both economic reasons and more stringent environmental requirements. Moreover, the possibilities for constructing large hydroelectric power stations in the European part of the country have practically been exhausted. In this regard, there is growing interest in using the energy of small rivers and watercourses. As is known, hydropower projects require large capital investments, but, at the same time, the costs of producing electricity are much lower. The construction of small hydroelectric power plants requires less initial investment, therefore it is more feasible in modern economic conditions. Large conventional hydroelectric power plants require the allocation of large areas for flooding, which leads to serious environmental consequences and leads to increased costs for environmental protection and costs for mitigating social impacts (resettlement of people, flooding of traditional habitats, etc.).

Properly designed small hydropower plants (usually less than 10 MW) usually integrate easily into the local ecosystem. Small hydropower plants make up the largest share among other electricity-generating renewable energy sources both in Europe and in the world. There are approximately 47 GW installed in the world with potential - technical and economic - Small hydropower in Russia - the current state is about 180 GW. In Europe, the installed capacity is about 9.5 GW, and it is planned to increase this capacity to 14 GW by 2010. In Russia there are currently about 300 small hydroelectric power stations and 50 microhydroelectric power stations with a total capacity of about 1.3 GW, which annually produce about 2.2 billion kWh of electricity. The most economically feasible areas for the development of small hydropower at present are:

* reconstruction and restoration of previously existing small hydroelectric power stations;

* construction of small and micro hydroelectric power stations at hydroelectric power stations under construction, on existing reservoirs for non-energy purposes with drops;

* construction of small hydroelectric power stations on small rivers.

Small hydroelectric power plants include stations with a capacity of up to 30 MW with a single unit capacity of up to 10 MW. Micro hydroelectric power plants include hydraulic units with a capacity of up to 100 kW. Most small hydroelectric power plants operate according to the so-called “run-of-river” scheme, that is, without the use of large reservoirs. Such tankless small hydroelectric power plants produce electricity when there is enough water in the river to operate hydraulic turbines; When the water flow drops below a certain value, the operation of the small hydroelectric power station stops. This means that autonomous schemes of small hydroelectric power plants cannot always provide continuous power supply, except in cases where the minimum river flow ensures normal operation of the hydroelectric power station. This problem can be solved in two ways. First, use existing upstream water reservoirs to regulate flow. Secondly, integrate the small hydroelectric power station into the centralized power supply system. This, on the one hand, allows you to automatically monitor the station and remotely control its parameters (voltage, frequency), but on the other hand, it leads to the need to sell electricity to power grids at their purchase price, which is usually significantly lower than the selling price. The undoubted advantage of small hydroelectric power plants is the ability to fully automate its operation, which leads to lower maintenance costs and, therefore, reduces the cost of the electricity produced.

Accidents and incidents at hydroelectric power plants

hydraulic power station

Accidents at hydroelectric power stations are not a frequent occurrence, however, they do occur. Here are some of them:

May 17, 1943 - British troops blew up dams on the rivers Möhne (Mönesee reservoir) and Eder (Edersee reservoir) during Operation Chastise, resulting in the death of 1,268 people, including about 700 Soviet prisoners of war.

October 9, 1963 - one of the largest hydraulic accidents at the Vajont dam in northern Italy.

On October 10, 2001, due to an earthquake on Lake Baikal, an accident occurred and a fire broke out at the substation of the Irkutsk hydroelectric power station. The cause of the accident was a short circuit in one of the substation transformers. An hour later the fire was extinguished. This did not affect the energy supply of the city and enterprises.

On March 11, 2004, a short circuit occurred at HPP_10, located on the Vuoksa River in the city of Svetogorsk, Vyborg district, Leningrad region. The station stopped, the gateways began to flood, and there was a danger of flooding the city, which was home to about 15 thousand people. The emergency service lifted the floodgates manually, and the threat of flooding of the city disappeared. The accident at the hydroelectric power station did not affect the supply of electricity to the city, since the power plant worked exclusively for the export of electricity. On the night of February 11, 2005, in the province of Baluchistan in southwestern Pakistan, a 150-meter hydroelectric dam near the city of Pasni burst due to heavy rains. As a result, several villages were flooded and more than 135 people died.

On February 6, 2006, in Talakan, Amur Region, at the Bureyskaya Hydroelectric Power Station, the largest thousand-ton crane at the power plant broke down. The hook came off the boom of the lifting device. While falling, he broke the station's water conduit, from which water immediately gushed out. Workers at the hydroelectric station blocked the water main sluice, preventing liquid from entering the transformer located not far from the hole.

On the night of August 19, 2006, at the Bureyskaya HPP (Amur region), the block transformer of the 4th hydraulic unit failed. The cause of the accident was an interturn short circuit in the high-voltage winding of the transformer. During the failure, all protections were activated sequentially. The transformer was taken out of operation by the operating personnel, i.e. there was no fire or explosion, and there were no casualties. However, the breakdown led to a long - more than a month - shutdown of the hydraulic unit.

On June 13, 2007, a fire occurred at the Zhigulevskaya hydroelectric power station in the Samara region. The garbage caught fire in one of the so-called hydroelectric power cans (40 by 40 meters in size). The fire resulted in heavy smoke. The fire was assigned the second complexity number. Firefighters from Tolyatti and Zhigulevsk fought the fire. The fire was extinguished after 4.5 hours. On October 5, 2007, on the Chu River in the Vietnamese province of Thanh Hoa, after a sharp rise in water level, the dam of the Kyadat hydroelectric station under construction burst. About 5 thousand houses were in the flood zone, 35 people died.

On September 12, 2007, a fire occurred at a block transformer at the Novosibirsk Hydroelectric Power Station. All people were evacuated from the hydroelectric power station building, no one was injured. The load on the station, which supplies electricity to part of the Sovetsky and Leninsky districts of Novosibirsk, was reduced to zero. The fire was completely extinguished within two hours.

On October 8, 2007, rolling blackouts occurred due to damage on the 500 kilovolt line of the Bureyskaya hydroelectric power station in Khabarovsk. Individual enterprises and several dozen residential buildings were cut off from power supply. The accident was caused by a rain cyclone with wind.

On February 27, 2008, a fire occurred at the Rybinsk hydroelectric power station in the Yaroslavl region. A fire occurred on the roof of the main building of the hydroelectric station; the roof burned over an area of 300 square meters. After 2.5 hours, the fire was extinguished. There were no casualties or injuries, the main equipment of the hydroelectric power station was not damaged. The incident did not affect the power generation of the hydroelectric power station. The backup line was promptly put into operation.

On August 17, 2009, an accident occurred at the Sayano-Shushenskaya hydroelectric power station, the most powerful power plant in Russia, located on the Yenisei River in Siberia. The emergency occurred during the repair of one of the hydraulic units of the hydroelectric power station; water rushed into the turbine room. The station was stopped, there was no dam failure and no flooding of residential areas. Due to the accident, the power supply to Siberian aluminum smelters was disrupted. As a result of the accident, 7 people died, 8 were taken to hospitals, and some people left the station on their own.

Conclusion

Despite the apparent abundance of fossil fuels available in the subsoil located within the borders Russian Federation, in the coming years the country will face a serious shortage of energy resources on the domestic market. This is understood by many serious specialists working in the Russian fuel and energy complex.

Taking into account the results of existing forecasts for the depletion of oil, natural gas and other traditional energy resources in the near future, as well as the reduction in coal consumption due to harmful emissions into the atmosphere, as well as the consumption of nuclear fuel, which, subject to the intensive development of breeder reactors, will be enough for at least For 1000 years, we can assume that at this stage of development of science and technology, thermal, nuclear and hydroelectric sources will prevail over other sources of electricity for a long time. Oil prices have already begun to rise, so hydraulic power plants will displace other types of power plants.

Some scientists and ecologists in the late 1990s. they talked about the imminent ban of nuclear power plants by Western European states. But based on modern analyzes of the commodity market and society's needs for electrical energy, such statements seem inappropriate.

Bibliography

Girshfeld V. Ya., Karol L. A. General course on power plants. Textbook A manual for students of energy and energy construction technical schools. - ed. 2nd, revised and additional - M.: “energy”. - 1976. - 272 p.

Kargiev V.M. Small hydropower in Russia - current state // Quarterly information bulletin “Renewable Energy”. - April, 2002. - p. 4-8

Larin V. State and prospects for the use of renewable energy sources in Russia // Electronic journal of the energy service company “Ecological Systems”. - 2009. - No. 4. [Electronic resource]. URL: http://esco-ecosys.narod.ru/2009_4/art154.pdf

Small hydropower in Russia // Information and analytical agency Cleandex. - 2008. [Electronic resource]. URL: http://www. cleanindex. ru/articles/2008/03/18/hydropower8

Emergency incidents at Russian hydroelectric power stations in 2001-2009. Help // Information agency “RIA Novosti”. - 2009. [Electronic resource]. URL: http://www.rian.ru/incidents/20090817/181228926.html

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Sayano-Shushenskaya HPP

Largest hydroelectric power station
in Russia

year of foundation: 1963

location: Cheryomushki village, Khakassia

number of employees: 580 people

The Sayano-Shushenskoye reservoir is formed by a hydroelectric dam. Its volume is 31 cubic kilometers. This dam is the tallest arch-gravity dam in the world, its height is 245 meters. The length of the ridge is 1,074 meters, the width of the base is 105 meters.

From the reservoir, water flows into the conduits. Each conduit has a diameter of 7.5 meters. About eleven thousand different sensors are installed in the body of the dam, monitoring the condition of the structure.

Water flows from the conduits to the turbines. Thanks to their rotation, generators are set in motion, which generate electricity.

Central control panel. The brain of the station, from where only two people control its work.

Ten hydroelectric units are installed in the SShHPP building, each with a capacity of 640 megawatts. Thus, the total capacity of the station is 6,400 megawatts, which is the largest power plant in Russia. Each of the ten hydraulic units of the SSHHPP can pass 350 cubic meters of water per second.

Restoration work in the turbine room of the Sayano-Shushenskaya HPP is now being completed, the last hydraulic unit is being restored, and finishing work is underway.

The equipment at the lower levels of the turbine hall was also completely updated.

Coming out of the turbines, the water downstream boils and forms whirlpools.

The operational spillway is used during heavy floods and can pass up to 13 thousand cubic meters of water per second.

Previously, current from the station was supplied to an open switchgear, which is now being dismantled.

Now its functions are performed by a complete gas-insulated switchgear located in a small enclosed room. It is much more reliable and safe, and requires much lower maintenance costs. It contains 19 cells, each of which contains switches, disconnectors, grounding switches, current and voltage measuring transformers, as well as a control cabinet. The cell nodes contain SF6 gas. It is a heavy gas and a very good insulator.

The station produces an average of 23.5 billion kilowatt-hours of electricity per year. Design capacity is 6,400 megawatts. The main consumers are the Sayan and Khakass aluminum smelters, enterprises of the Krasnoyarsk Territory and the Kemerovo Region. In addition, the station is the regulator for the entire energy system of Siberia.

Photos: Ivan Gushchin

What is a hydroelectric power plant?

Hydroelectric power plants are very efficient sources of energy. They use renewable resources - the mechanical energy of falling water. The water back-up necessary for this is created by dams that are erected on rivers and canals. Hydraulic installations make it possible to reduce transportation and save mineral fuel (approximately 0.4 tons of coal are consumed per 1 kWh). They are quite easy to operate and have a very high efficiency (more than 80%). The cost of this type of installation is 5-6 times lower than thermal power plants, and they require much less maintenance personnel.

The pressure of a hydroelectric power station is created by the concentration of the fall of the river on the site being used by a dam, or diversion, or a dam and diversion together. The main power equipment of a hydroelectric power station is located in the hydroelectric power station building: in the turbine room of the power plant - hydraulic units, auxiliary equipment, automatic control and monitoring devices; in the central control post there is a control panel for the operator-dispatcher or an automatic operator of the hydroelectric power station. The step-up transformer substation is located both inside the hydroelectric power station building and in separate buildings or in open areas. Switchgears are often located in open areas. A hydroelectric power plant building can be divided into sections with one or more units and auxiliary equipment, separated from adjacent parts of the building. An installation site is created at or inside the hydroelectric power station building for the assembly and repair of various equipment and for auxiliary operations for the maintenance of the hydroelectric power station.

According to the maximum used pressure, hydroelectric power stations are divided into high-pressure (more than 60 m), medium-pressure (from 25 to 60 m) and low-pressure (from 3 to 25 m) hydroelectric power stations. On lowland rivers, pressures rarely exceed 100 m; in mountainous conditions, pressures of up to 300 m or more can be created using a dam, and with the help of diversion - up to 1500 m. The classification by pressure approximately corresponds to the types of power equipment used: at high-pressure hydroelectric power stations, bucket and radial hydroelectric power plants are used. axial turbines with metal spiral chambers; on medium-pressure ones - rotary-blade and radial-axial turbines with reinforced concrete and metal spiral chambers, on low-pressure ones - rotary-blade turbines in reinforced concrete spiral chambers, sometimes horizontal turbines in capsules or in open chambers. The division of hydroelectric power stations according to the pressure used is of an approximate, conditional nature.

According to the scheme of water resource use and pressure concentration, hydroelectric power stations are usually divided into run-of-river, dam-based, diversion with pressure and free-flow diversion, mixed, pumped storage and tidal. In run-of-river and dam-based hydroelectric power plants, the water pressure is created by a dam that blocks the river and raises the water level in the upper pool. At the same time, some flooding of the river valley is inevitable. If two dams are built on the same section of the river, the flood area is reduced. On lowland rivers, the largest economically permissible flood area limits the height of the dam. Run-of-river and near-dam hydroelectric power stations are built both on lowland high-water rivers and on mountain rivers, in narrow compressed valleys.

In accordance with the purpose of the waterworks, it may include shipping locks or a ship lift, fish passage structures, water intake structures for irrigation and water supply. In run-of-the-river hydroelectric power plants, sometimes the only structure that allows water to pass through is the power plant building. In these cases, useful water sequentially passes through the inlet section with waste-retaining gratings, a spiral chamber, a hydraulic turbine, and a suction pipe, and the river's flood flows are discharged through special conduits between adjacent turbine chambers. Run-of-river hydroelectric power plants are characterized by pressures of up to 30-40 m; The simplest run-of-river hydroelectric power plants also include previously built rural (hydroelectric power stations) hydroelectric power stations of small capacity. On large lowland rivers, the main channel is blocked by an earthen dam, adjacent to which is a concrete spillway dam and a hydroelectric power station building is constructed. This arrangement is typical for many domestic hydroelectric power plants on large lowland rivers. Volzhskaya HPP named after. 22nd Congress of the CPSU - the largest among the river-bed stations.

When constructing hydroelectric power stations, the goal is usually to generate electricity, improve conditions for navigation on the river and irrigate land. Hydroelectric power plants usually have reservoirs that allow them to store water and regulate its flow and, therefore, the operating power of the station so as to provide the most beneficial mode for the energy system as a whole.

The regulatory process is as follows. During a period of time when the load on the power system is low (or the natural inflow of water in the river is large), the hydroelectric power station consumes water in an amount less than the natural inflow. In this case, water accumulates in the reservoir, and the operating capacity of the station is relatively small. At other times, when the system load is high (or the water inflow is small), the hydroelectric power plant uses water in an amount that exceeds the natural inflow. In this case, the water accumulated in the reservoir is consumed, and the operating power of the station increases to maximum. Depending on the volume of the reservoir, the regulation period, or the time required to fill and operate the reservoir, can be a day, a week, several months or more. During this time, the hydroelectric power plant can use a strictly defined amount of water, determined by natural inflow.

When hydroelectric power plants operate together with thermal and nuclear power plants, the load of the power system is distributed between them so that, at a given water flow during the period under consideration, the demand for electrical energy is met with minimal fuel consumption (or minimal costs for fuel) in the system. Experience in operating energy systems shows that during most of the year it is advisable to operate hydroelectric power plants in peak mode. This means that during the day the operating power of a hydroelectric power station must vary within wide limits - from minimum during hours when the load on the power system is low to maximum during hours of the highest load on the system. With this use of hydroelectric power plants, the load of thermal stations is leveled and their operation becomes more economical.

During periods of flood, when the natural influx of water in the river is high, it is advisable to use hydroelectric power stations around the clock with an operating power close to maximum, and thus reduce idle water discharge through the dam. The most profitable mode of a hydroelectric power plant depends on many factors and must be determined by appropriate calculations.

The operation of hydroelectric power plants is characterized by frequent starts and stops of units, a rapid change in operating power from zero to nominal. Hydraulic turbines by their nature are adapted to this regime. For hydrogenerators, this mode is also acceptable, since, unlike steam turbine generators, the axial length of the hydrogenerator is relatively small and temperature deformations of the winding rods are less pronounced. The process of starting the hydraulic unit and gaining power is fully automated and requires only a few minutes.

The duration of use of the installed capacity of hydroelectric power plants is usually shorter than that of thermal power plants. It is 1500-3000 hours for peak stations and up to 5000-6000 hours for base stations.

The unit cost of a hydroelectric station (RUB/MW) is higher than the unit cost of a thermal station of the same capacity due to the larger volume of construction work. The construction time of a hydroelectric power station is also longer than the construction time of a thermal station. However, the cost of electricity generated by hydroelectric power plants is significantly lower than the cost of energy from thermal power plants, since operating costs do not include the cost of fuel.

It is advisable to build hydroelectric power stations on mountain and sesquicentral rivers. On lowland rivers, their construction can lead to the flooding of large areas of floodplain meadows and arable land, forests, a decrease in fish stocks and other consequences.

In the power system, hydroelectric power stations are usually used to generate electricity, cover the load curve, especially its peak part, regulate the frequency of electric current in the system, as a reserve and to generate reactive power in synchronous compensator mode.

The operating mode of a hydroelectric power station in the power system depends on water flow, pressure, reservoir volume, the needs of the power system, and restrictions on the upstream and downstream.

Hydroelectric power station units technical specifications can quickly turn on, gain load and stop. Moreover, switching units on and off and load regulation can occur automatically when the frequency of the electric current in the power system changes. It usually takes only 1-2 minutes to turn on a stopped unit and reach full load.

The hydraulic turbine shaft power (kW) is defined as

where t is the water flow through the hydraulic turbine, m 3 /s;
N t - turbine pressure, m;
η t - coefficient of performance (efficiency) of the turbine.

The turbine pressure is:

where ∇ВБ, ∇НБ - water level marks in the upper and lower pools, respectively, m;
N g - geometric pressure;
∆h - pressure loss in the water supply path, m.

The pressure loss is usually 2-5% Ng. The efficiency of a hydraulic turbine depends on its design, size and operating modes. The efficiency of modern large hydraulic turbines can reach 0.95.

Electric power of the hydraulic unit N a at the generator terminals

(17.9)

where η gene is the efficiency of the hydrogenerator.

Typically, the efficiency of a hydrogenerator is 0.9-0.98.

The power of a hydroelectric power plant is controlled by changing the flow rate passing through the hydraulic turbine. Hydroelectric power capacity in i-th moment time is equal to:

(17.10)

where gi, Hgi, η gi are the HPP flow rate, the HPP pressure and the HPP efficiency, respectively, at the i-th point in time.

Hydroelectric power generation (kW h) over time period T (h) is defined as

(17.11)

The calculation period T is considered to be an hour, a day, a week, a month, or a year.

The annual electricity production of a hydroelectric power station is not a constant value, but varies depending on the volume of runoff entering the reservoir, the degree of its regulation and the operating conditions of the hydroelectric power station. With annual regulation, the annual electricity production of hydroelectric power plants, as a rule, fluctuates significantly, mainly due to energy output during the flood period.

With long-term regulation, the unevenness of electricity generation over the years is insignificant.

Average long-term electricity production is an important characteristic used in determining the technical and economic indicators of hydroelectric power plants.

To evaluate the operation of hydroelectric power plants in the energy system, the conditional number of hours of use of installed capacity per year T y is used, which is the ratio:

where N y is the installed capacity of the hydroelectric power station;
g - average annual output.

For peak hydroelectric power plants, T y ≤ 2000 h, and for hydroelectric power plants operating in semi-peak mode, T y increases to 4000 h. If the hydroelectric power station is intended for basic operation, then T y is usually 6000-6500 h. The theoretical limit is T y = 8760 h .

The operating personnel at a hydroelectric power station are significantly smaller than at a thermal or nuclear power plant of similar capacity.

The cost of generating electricity at hydroelectric power plants is usually 6-8 times lower than at thermal power plants or nuclear power plants.

The operating principle of a hydroelectric power station is quite simple. Hydraulic structures Hydroelectric power plants provide the necessary flow of water to the blades of a hydraulic turbine, which leads to a generator that produces electricity.

Fig.1. Diagram of one of the types of hydraulic turbines

The required water pressure is generated by a dam (in the case of a dam-type hydroelectric power station) or diversion - the natural flow of water (diversional hydroelectric power stations). In some cases, to obtain the required water pressure, both a dam and a diversion are used together:

dam hydroelectric power stations (Fig. 2). These are the most common types of large hydroelectric power plants in Kyrgyzstan. The water pressure in them is created by installing a dam that completely blocks the river and raises the water level in it to the required height. In this case, the hydroelectric power station building itself is located behind the dam, in its lower part. Water, in this case, is supplied to the turbines through special pressure tunnels.
diversion hydroelectric power stations (Fig. 3). Such power plants are built in places where there is a river slope. The required amount of water to create pressure is removed from the river bed through special drainage systems (canals, branches, ditches). Their slope is significantly less than the average slope of the river. As a result, the water, after a certain distance, rises to the required height and is collected in a pressure pool. From there, through a pressure pipeline, water enters the turbine and, ultimately, ends up again in the same river. In some cases, a dam and a small reservoir are created at the beginning of the diversion canal.

Rice. 2. Dam-type hydroelectric power station

Rice. 3. Hydroelectric power station of diversion type

All power equipment is located directly in the hydroelectric power station building itself. Depending on the purpose, it has its own specific division. Hydrogenerators are located in the turbine room, directly converting water energy into electrical energy. There is also electrical equipment, which includes control and monitoring devices for the operation of hydroelectric power stations, a transformer station, switchgears and much more.

Hydroelectric stations are divided depending on the power generated:

powerful - produce from 30 MW and above;
small hydroelectric power plants - from 1 MW to 30 MW;
mini hydroelectric power station - from 100 kW to 1 MW;
micro hydroelectric power station - from 5 kW to 100 kW;
pico hydroelectric power station - up to 5 kW.

The power of a hydroelectric power station depends on the pressure and flow of water, as well as on the efficiency (coefficient of efficiency) of the turbines and generators used. Due to the fact that, for natural reasons, water flow is constantly changing, depending on the season, as well as for a number of other reasons, it is customary to take cyclic power as an expression of the power of a hydroelectric station. For example, there are annual, monthly, weekly or daily cycles of operation of a hydroelectric power station.

Depending on the flow and pressure of water, different types of turbines are used in hydroelectric power plants. For high-pressure - bucket and radial-axial turbines with metal spiral chambers. At medium-pressure hydroelectric power plants, rotary-blade and radial-axial turbines are installed, at low-pressure hydroelectric power stations, rotary-blade turbines are installed in reinforced concrete or steel chambers. The operating principle of all types of turbines is the same - water under pressure (water pressure) enters the turbine blades, which begin to rotate. Mechanical energy is thus transferred to the generator, which generates electricity. Turbines differ in some ways technical characteristics, as well as chambers - steel or reinforced concrete, and are designed for different water pressures.

Hydroelectric power stations, depending on their purpose, may also include additional structures, such as locks, fish passages, water intake structures used for irrigation, and much more.

The value of hydroelectric power plants lies in the fact that they use renewable natural resources to produce electrical energy. Due to the fact that there is no need for additional fuel for hydroelectric power plants, the final cost of the generated electricity is significantly lower than when using other types of power plants.

Features of hydroelectric power plants (pros and cons)

(+) the cost of electricity at hydroelectric power plants is more than two times lower than at thermal power plants.
(+) hydroelectric turbines allow operation in all modes from zero to maximum power and allow you to quickly change power if necessary, acting as a regulator of electricity generation.
(+) river flow is a renewable energy source
(+) significantly less impact on the air and glaciers than other types of power plants.
(-) often efficient hydroelectric power plants are more distant from consumers and require the construction of expensive power transmission lines (PTL).
(-) Reservoirs often occupy large areas.
(-) dams often change the nature of fisheries, since they block the path to spawning grounds for migratory fish, but often favor an increase in fish stocks in the reservoir itself and the implementation of fish farming.

Hydroelectric power station operating principle diagram. Hydroelectric power station - what is it? List of the largest hydroelectric power stations in Russia. Based on the height of the pressure flow, hydroelectric power stations are divided into

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