Power industry

For a long time, electric energy was only an object of experiments and had no practical application. The first attempts to make good use of electricity were made in the second half of the 19th century , the main areas of use were the recently invented telegraph , electroplating , military equipment (for example, there were attempts to create ships and self-propelled vehicles with electric engines ; mines with an electric fuse were developed). 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 with galvanic cells, generators had more power and useful life, were significantly cheaper and allowed to arbitrarily set the parameters of the generated current. It was with the advent of generators that the first electric stations and networks began to appear (before that, energy sources were directly in the places of its consumption) - 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 started operating in 1891 . The length of the line was 170 km , voltage 28.3 kV , transmitted power 220 kW ^[2] . At that time, electric energy was used mainly for lighting in large cities . Electric companies were in serious competition with gas: electric lighting was superior to gas in a number of technical parameters, but at that time it was much more expensive. With the improvement of electrical equipment and an increase in the efficiency of generators, the cost of electric energy decreased, and in the end, electric lighting completely replaced gas. Along the way, new areas of application of electric energy appeared: improved electric lifts, pumps and electric motors. An important step was the invention of the electric tram : tram systems were large consumers of electric energy and stimulated the increase in capacity of power plants . In many cities, the first power plants 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 ability to transmit over long distances - AC transmission was realized easier and cheaper, which led to his victory in this “war”: currently, AC is used almost everywhere. Nevertheless, there are currently prospects for the widespread use of direct current for long-distance transmission of high power (see. High-voltage direct current line ).

History of Russian Electricity

The history of the Russian, and perhaps the world’s electric power industry dates back to 1891 , when the outstanding scientist Mikhail Osipovich Dolivo-Dobrovolsky carried out the practical transfer of electric power of about 220 kW to a distance of 175 km. The resulting power line efficiency of 77.4% turned out to be sensationally high for such a complex multi-element design. This high efficiency was achieved through the use of three-phase voltage , invented by the scientist himself.

In pre-revolutionary Russia, the power of all power plants was only 1.1 million kW, and annual electricity production was 1.9 billion kWh. After the revolution, at the suggestion of V.I. Lenin , the famous electrification plan of Russia GOELRO was developed. It provided for the construction of 30 power plants with a total capacity of 1.5 million kW, which was realized by 1931, and by 1935 it was overfulfilled by 3 times.

In 1940, the total capacity of Soviet power plants amounted to 10.7 million kW, and the annual electricity generation exceeded 50 billion kWh, which was 25 times higher than the corresponding figures for 1913. After the break caused by the Great Patriotic War , the electrification of the USSR resumed, reaching the level of production of 90 billion kWh in 1950 .

In the 50s of the 20th century, power plants such as Tsimlyanskaya , Gyumushskaya, Verkhne-Svirskaya , Mingachevirskaya and others were launched. Since the mid 60-ies of the USSR took the second place in the world in electricity generation after the United States ^[3] .

History of Belarusian Electricity

The first information on the use of electric energy in Belarus dates to the end of the 19th century. However, at the beginning of the last century, the energy base of Belarus was at a very low level of development, which determined the backwardness of commodity production and the social sphere: there were almost five times less industrial output per inhabitant than the average for the Russian Empire. The main sources of lighting in cities and villages were kerosene lamps, candles, and torches.

The first power station in Minsk appeared in 1894. She had a capacity of 300 liters. with. By 1913, three diesel engines of various companies were installed at the station and its capacity reached 1,400 liters. with.

In November 1897, the first current was given by a direct current power plant in the city of Vitebsk .

In 1913, on the territory of Belarus there was only one advanced steam turbine power plant with technical equipment, which belonged to the Dobrush paper mill.

The development of the energy complex of Belarus began with the implementation of the GOELRO plan , which became the first long-term plan for the development of the national economy of the Soviet state after the 1917 revolution. The solution to the daunting task of electrifying the whole country made it possible to intensify work on the restoration, expansion and construction of new power plants in our republic. If in 1913 the capacity of all power plants in Belarus was only 5.3 MW, and the annual electricity production was 4.2 million kWh, then by the end of the 30s the installed capacity of the Belarusian energy system had already reached 129 MW with an annual electricity generation of 508 million kWh ^[4] .

The rapid development of the industry began with the commissioning of the first stage of the Belarusian State District Power Plant with a capacity of 10 MW, the largest station in the pre-war period. BelGRES gave a powerful impetus to the development of electric networks of 35 and 110 kV. A technologically controlled complex has developed in the republic: a power plant - electric networks - consumers of electricity. The Belarusian energy system was created de facto, and on May 15, 1931, a decision was made to organize the Belenergo, the regional department of state power stations and networks of the Belarusian SSR.

For many years, the Belarusian State District Power Plant remained the leading power station in the republic. At the same time, in the 1930s, the development of the energy industry was taking leaps and bounds - new thermal power plants appeared, the length of high-voltage lines increased significantly, and the potential of professional personnel was created. However, this bright leap forward was crossed out by the Great Patriotic War. The war led to the almost complete destruction of the republic’s electricity base. After the liberation of Belarus, the capacity of its power plants was only 3.4 MW.

Power engineers needed, without exaggeration, the heroic efforts in order to restore and exceed the pre-war level of installed capacity of power plants and electricity production.

In the following decades, the industry continued to develop, its structure was improved, and new energy enterprises were created. At the end of 1964, for the first time in Belarus, the 330 kV power line Minsk-Vilnius was launched, which integrated our power system into the United North-West Power System connected to the Unified Power System of the European part of the USSR.

The capacity of power plants in the years 1960-1970 increased from 756 to 3464 MW, and the production of electricity increased from 2.6 to 14.8 billion kWh.

Further development of the country's energy sector led to the fact that in 1975 the capacity of power plants reached 5487 MW, electricity production almost doubled compared to 1970. In the subsequent period, the development of the electric power industry slowed down: in comparison with 1975, the capacity of power plants in 1991 increased a little more than 11%, and electricity production - by 7%.

In 1960-1990, the total length of power grids grew 7.3 times. The length of the backbone OHL of 220–750 kV over the course of 30 years increased by 16 times and reached 5875 km.

As of January 1, 2010, the republic’s power plants amounted to 8,386.2 MW, including 7,983.8 MW for Belenergo. This capacity is enough to fully satisfy the country's demand for electric energy. At the same time, from 2.4 to 4.5 billion kWh is imported annually from Russia, Ukraine, Lithuania and Latvia in order to load the most efficient capacities and taking into account the repair of power plants. Such supplies contribute to the stability of parallel operation of the energy system of Belarus with other energy systems and reliable energy supply to consumers ^[5] .

Dynamics of world electricity production (Year - billion kWh):

• 1890 - 9
• 1900 - 15
• 1914 - 37.5
• 1950-950
• 1960-2300
• 1970 - 5000
• 1980 - 8250
• 1990 - 11800
• 2000 - 14500
• 2005 - 18138.3
• 2007 - 19894.8
• 2013 - 23127 ^[6]
• 2014 - 23536.5 ^[7]
• 2015 - 24255 ^[8]
• 2016 - 24816 ^[9]

The largest electricity producing countries in the world are China and the USA , generating 25% and 18% of world production, respectively, and also yielding to them about 4 times each - India , Russia , Japan .

Power Generation

Electricity generation is the process of converting various types of energy into electrical energy at industrial facilities called power plants. Currently, the following types of generation exist:

• Thermal power industry . In this case, the thermal energy of the combustion of organic fuels is converted into electrical energy. Thermal power industry includes thermal power plants ( TPPs ), which are of two main types:
  • Condensation ( IES , the old abbreviation GRES is also used);
  • Cogeneration (cogeneration plants, CHP ). Cogeneration is the combined generation of electrical and thermal energy at the same station;

IES and TPPs have similar technological processes. In both cases, there is a boiler in which fuel is burned and steam is heated under pressure due to the generated heat. Next, the heated steam is fed into a steam turbine , where its thermal energy is converted into rotational energy. The turbine shaft rotates the rotor of the generator - thus, the rotation energy is converted into electrical energy, which is supplied to the network. The principal difference between the CHPP and the IES is that part of the steam heated in the boiler goes to heat supply needs;

• Nuclear power It includes nuclear power plants ( NPPs ). In practice, nuclear power is often considered a subspecies of the thermal power industry, since, in general, the principle of generating electricity at nuclear power plants is the same as at thermal power plants. Only in this case, thermal energy is released not during the burning of fuel, but during the fission of atomic nuclei in a nuclear reactor . Further, the scheme for generating electricity is fundamentally no different from thermal power plants: steam is heated in the reactor, enters the steam turbine, etc. Due to some design features of nuclear power plants, it is unprofitable to use in combined generation, although separate experiments in this direction were carried out;
• Hydropower It includes hydroelectric power plants ( HPS ). In hydropower, the kinetic energy of the flow of water is converted into electrical energy. To do this, with the help of dams on the rivers, a difference in the levels of the water surface (the so-called upper and lower pools) is artificially created. Water, under the action of gravity, overflows from the upstream to the downstream through special channels in which water turbines are located, the blades of which are untwisted by the water flow. The turbine rotates the rotor of the electric generator. A special type of hydroelectric station is the pumped storage stations ( PSP ). They cannot be considered generating capacities in their pure form, since they consume almost as much electricity as they produce, however, such stations cope very effectively with unloading the network at peak hours.

Recently, studies have shown that the power of sea currents is many orders of magnitude greater than the power of all the rivers of the world. In this regard, the creation of pilot offshore hydroelectric power plants is underway.

• • Wind energy - the use of kinetic wind energy to generate electricity;
  • Solar energy - obtaining electric energy from the energy of sunlight ;

    The common disadvantages of wind and solar energy are the relative low power of generators at their high cost. Also, in both cases, storage capacities for nighttime (for solar energy) and windless (for wind energy) time are required;

  • Geothermal energy - the use of the Earth's natural heat to generate electrical energy. In fact, geothermal stations are ordinary thermal power plants where the source of heat for heating steam is not a boiler or a nuclear reactor, but underground sources of natural heat. The disadvantage of such stations is the geographical limitations of their application: it is cost-effective to build geothermal stations only in regions of tectonic activity, that is, where natural sources of heat are most available;
  • Hydrogen energy - the use of hydrogen as an energy fuel has great prospects: hydrogen has a very high combustion efficiency , its resource is almost unlimited, hydrogen burning is absolutely environmentally friendly (distilled water is the product of combustion in an oxygen atmosphere). However, hydrogen energy is currently not able to fully satisfy the needs of mankind due to the high cost of producing pure hydrogen and the technical problems of its transportation in large quantities. In fact, hydrogen is just a carrier of energy, and does not solve the problem of producing this energy.
  • Tidal energy uses the energy of tides . The proliferation of this type of electric power industry is hindered by the need for too many factors to coincide when designing a power plant: not just a sea coast, but a coast on which the tides are strong and constant enough. For example, the Black Sea coast is not suitable for the construction of tidal power plants, since the water level differences in the Black Sea during tides are low.
  • Wave energy, with careful consideration, may turn out to be the most promising. Waves are concentrated energy of the same solar radiation and wind. The power of the waves in different places can exceed 100 kW per linear meter of the wavefront. Excitement is almost always, even in calm (" dead swell "). In the Black Sea, the average wave power is approximately 15 kW / m. Northern seas of Russia - up to 100 kW / m. The use of waves can provide energy to marine and coastal settlements. Waves can propel ships. The power of the ship’s average pitching is several times greater than the power of its power plant. But so far, wave power plants have not gone beyond the scope of single prototypes.

Transmission and distribution of electrical energy

Electric energy is transferred from power plants to consumers via electrical networks . The electric grid economy is a naturally monopolistic sector of the electric power industry: the consumer can choose from whom to buy electricity (that is, the energy distribution company), the electricity distribution company can choose among wholesale suppliers (electricity producers), however, the network through which electricity is supplied is usually one, and the consumer is technically unable to choose the grid company. From a technical point of view, the electric network is a combination of power lines (power lines) and transformers located in substations .

• Power lines are a metal conductor through which electric current passes. Currently, AC is used almost everywhere. The power supply in the vast majority of cases is three-phase , therefore the power line, as a rule, consists of three phases, each of which can include several wires. Structurally, power lines are divided into air and cable .
  • Overhead lines (OHL) are suspended above the ground at a safe height on special structures called supports. Typically, an overhead wire does not have surface insulation; insulation is available at the points of attachment to the supports. There are lightning protection systems on overhead lines. The main advantage of overhead power lines is their relative cheapness compared to cable. Maintainability is also much better (especially in comparison with brushless cable lines): it is not necessary to carry out earthwork to replace the wire, it is not difficult to visually check the condition of the line. However, aerial power lines have several disadvantages:
    • wide alienation zone: in the vicinity of power lines it is forbidden to put any structures and plant trees; when the line passes through the forest, trees are cut down along the entire width of the exclusion zone;
    • insecurity from external influences, for example, falling trees on the line and theft of wires; Despite lightning protection devices, overhead lines also suffer from lightning strikes. Due to vulnerability, two circuits are often equipped on the same overhead line: main and backup;
    • aesthetic unattractiveness; This is one of the reasons for the almost universal transition to cable method of power transmission in the city.
  • Cable lines (KL) are conducted underground. Electric cables have a different design, but common elements can be identified. Сердцевиной кабеля являются три токопроводящие жилы (по числу фаз). Кабели имеют как внешнюю, так и междужильную изоляцию. Обычно в качестве изолятора выступает трансформаторное масло в жидком виде, или промасленная бумага. Токопроводящая сердцевина кабеля, как правило, защищается стальной бронёй. С внешней стороны кабель покрывается битумом. Бывают коллекторные и бесколлекторные кабельные линии. В первом случае кабель прокладывается в подземных бетонных каналах — коллекторах . Через определённые промежутки на линии оборудуются выходы на поверхность в виде люков — для удобства проникновения ремонтных бригад в коллектор. Бесколлекторные кабельные линии прокладываются непосредственно в грунте. Бесколлекторные линии существенно дешевле коллекторных при строительстве, однако их эксплуатация более затратна в связи с недоступностью кабеля. Главным достоинством кабельных линий электропередачи (по сравнению с воздушными) является отсутствие широкой полосы отчуждения. При условии достаточно глубокого заложения, различные сооружения (в том числе жилые) могут строиться непосредственно над коллекторной линией. В случае бесколлекторного заложения строительство возможно в непосредственной близости от линии. Кабельные линии не портят своим видом городской пейзаж, они гораздо лучше воздушных защищены от внешнего воздействия. К недостаткам кабельных линий электропередачи можно отнести высокую стоимость строительства и последующей эксплуатации: даже в случае бесколлекторной укладки сметная стоимость погонного метра кабельной линии в разы выше, чем стоимость воздушной линии того же класса напряжения . Кабельные линии менее доступны для визуального наблюдения их состояния (а в случае бесколлекторной укладки — вообще недоступны), что также является существенным эксплуатационным недостатком.

Потребление электрической энергии

По данным Управления по энергетической информации США (EIA — US Energy Information Administration) в 2008 году мировое потребление электроэнергии составило около 17,4 трлн кВт•ч . ^[ten]

Оперативно-диспетчерское управление

Система оперативно-диспетчерского управления в электроэнергетике включает в себя комплекс мер по централизованному управлению технологическими режимами работы объектов электроэнергетики и энергопринимающих установок потребителей в пределах Единой энергетической системы России и технологически изолированных территориальных электроэнергетических систем, осуществляемому субъектами оперативно-диспетчерского управления, уполномоченными на осуществление указанных мер в порядке, установленном Федеральным законом «Об электроэнергетике» ^[1] . Оперативное управление в электроэнергетике называют диспетчерским, потому что оно осуществляется специализированными диспетчерскими службами. Диспетчерское управление производится централизованно и непрерывно в течение суток под руководством оперативных руководителей энергосистемы — диспетчеров ^[11] .

Энергосбыт

• Energetics
• alternative energy
• Список стран по производству электроэнергии
• Electric power

• Бурман, А.П.; Строев, В.А. Современная электроэнергетика. In 2 volumes. — 4-е, перераб. и доп.. — М. : МЭИ , 2008. — 632 с. — ISBN 978-5-383-00163-9 .

• Вайнзихер, Б.Ф. Электроэнергетика России 2030: Целевое видение. - М., Альпина бизнес букс, 2008. - 360 с. - ISBN 978-5-9614-0844-7 ;

• Электроснабжение — статья из Большой советской энциклопедии .