POWER ENGINEERING. POWER STATIONS - Студенческий научный форум

X Международная студенческая научная конференция Студенческий научный форум - 2018

POWER ENGINEERING. POWER STATIONS

Стрельцов Н.С. 1
1Владимирский государственный университет
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The energy industry is energy, which includes generation, transmission and distribution of electricity. Electricity is the most important energy sector, due to such advantages of electricity before the energy of other types, such as relative ease of long-distance transmission. Electricity provides electrical operation of various industries and human activities. Electro-power is a leading component of the energy, providing power deification economy based on rational production and distribution of electricity. Electricity is important in Ho-seeder used on the farm any country, due to such advantages of electricity before the energy of other types, such as relative ease of transmission over long distances distribution between consumers and conversion into other forms of energy (mechanical, thermal, chemical, light target, etc.). A distinctive feature of electricity is its simultaneous generation and consumption. The most common types of power plants are: thermal power plants, hydro and nuclear power. There is also a thermal power plant by coal, oil, gas. In most of the most common is TES plea. Overall electricity generation on coal is typical for countries of Asia, Africa and Central Europe. HPP lead in Latin America. A significant proportion of NPP is in developed countries.

Thermal power plant

Thermal power plant(TPP) is a power plant producing electrical energy by converting chemical energy of fuel combustion into heat and then into mechanical energy of rotation of the shaft of the generator. Most of the power (2/3) is produced by thermal power plants, they are the most common types of power plants. In some countries the share of electricity-the may TPP exceeds 80% (Poland, South Africa, Saudi Arabia, Libya, Bahrain, Iraq, Denmark). For his work, the power plants use coal, natural gas, oil, shale, peat. Thermal power plants running on natural gas, considered more environmentally friendly than those that work on the nave-leum products and coal. In this case, thermal energy is converted into electrical cal. Thermal power plants have a number of drawbacks: a thermal power plant for its operation requires huge amount of human resources required to service these stations; resources used by thermal power plants, finite and non-renewable; thermal power plants is very poorly regulated, for stopping and launching takes a very long time; in addition, the combustion of fuel you determined many harmful substances that go into the atmosphere, so plants are the main pollutant of atmospheric air. But thermal power plants have big advantages that make them the most common in Russia and in the world. They are very easy and fast with-rugayutsya produce electricity year-round without seasonal fluctuations in the amount of electricity generated, in addition, they can be constructed as sources of raw materials and about the consumer. Thermal power plants are of two types: condensing and combined heat and power. The most popular condensing power plant. If they maintenance give out large areas and produce large amounts of electricity, they are referred to as state district power plants, or SDPP. In the European part of Russia GRES often used fuel oil and coal.

Nuclear power plant

Nuclear power is a complex of necessary systems, devices, equipment and facilities intended for the production of electrical energy. The fuel is uranium-235. The presence of the nuclear reactor distinguishes the plant from other plants. Of the country, is produced by-penetration the major part of nuclear electricity: France, Belgium, Lithuania, Slovenia. Modern power plants are competitive enough: do not emit greenhouse gases into the atmosphere (unlike the TPP), produced by serif-Ute quite a lot of electricity. But, due to some accidents that occurred at nuclear power plants, many countries have revised their attitude to this type of stations, up to complete refusal from their use. Currently, nuclear power produces 15% of electricity in Russia. In comparison with thermal power plants, nuclear power plants have several advantages: does not require constant and large supply of fuel, because one kilogram of uranium replaces 2,500 tons of coal, this type of power plants it is convenient to place in electrodeposited places and UDA-industrial areas, and during the normal operation of a nuclear power plant turns out-yet minor impact on the environment. A method of operating a nuclear power plant in Chernobyl and Fukushima showed that this type of power has several disadvantages, first of all its dire consequences that occur after the accidents at nuclear power plants. In addition, still have not developed technology of recycling of waste generated during the operation of nuclear power plants. Also, nuclear power plants are the most expensive in terms of construction and built for long enough. The station is poorly regulated: for stopping and inclusion requires a few weeks. Currently in Russia there are 10 nuclear power plants. OS-widespread part of the power plants located in the European part of the country is but novoronezhsky NPP, Leningrad NPP on the Ural is of Beloyarsk NPP, on the North of the European part is the Kola nuclear power plant, Chukotka Belinskaya nuclear power plants.

Hydroelectric

Hydroelectric power plant (HPP) is a plant used as a source of energy the energy of water masses in the fluvial watercourses or tidal movements. Hydroelectric plants are usually built on rivers, building dams and reservoirs. For the efficient production of electricity at hydroelectric power plants requires two main factors: guaranteed availability of water all year round, and possibly steep slopes, rivers, conducive to the water engineering of the canyon-like terrain. The working principle of hydropower is quite simple. Circuit waterworks provides the necessary water pressure entering the blades of the turbine which drives the generators that produce electricity. Required water pressure is created by the construction of the dam, and as a consequence the concentration of the river in a certain place, or the derivation of natural flow of water. In some cases, obtaining the required water pressure use together and the dam, and the diversion. Directly in the building of hydroelectric power is all the power equipment. Depending on the destination, it has its particular division. In the engine room are located the units directly converts the energy of water flow into electrical energy. There are all sorts of additional equipment, device control and control over hydroelectric power station, transformer station, switchgear and more. Features:

• The cost of electricity at Russian hydroelectric power station more than two times lower than in thermal power plants.

• Turbine hydroelectric power station will allow all the modes from zero to its maximum capacity and can change capacity if needed, acting as the regulator of electricity generation.

• The flow of the river is a renewable source of energy.

• The construction of hydropower plants is generally more capital intensive than thermal plants.

Hydroelectric power depends on the pressure and flow rate, and efficiency of used turbines and generators. Due to the fact that according to natural laws the water level is constantly changing depending on the season, and for a number of reasons, as an expression of power of a hydroelectric power station decided to take a cyclical power. For example, there are annual, monthly, weekly or daily cycles of operation of the power station. Like other power plants at the power station has its pros and cons.

Advantages:

• the use of renewable energy;

• very cheap electricity;

• work is not accompanied by harmful emissions into the atmosphere;

• fast (relative to TPP/TPP) exit to the extradition regime operating power after switching on station.

Disadvantages:

• flooding of arable lands;

• the construction is carried out only where there are large reserves of water power;

• mountain river dangerous due to the high seismicity areas;

Alternative energy

Alternative energy — a set of promising methods of obtaining, transfer and use of energy, which are not as widespread as traditional, but are of interest because of the profitability of their use at generally low risk of harm to the environment. The main direction of alternative energy is to find and use alternative (non-traditional) sources of energy. Sources of energy — "occurring in nature substances and processes that allow a person to obtain the necessary for the existence of energy". An alternative source of energy is a renewable resource, it can replace the traditional energy sources functioning on oil, produced natural gas and coal, which when burned emit into the atmosphere carbon dioxide, contributing to the growth of the greenhouse effect and global warming. The reason for the search for alternative sources of energy — need to get it from the energy of renewable or almost inexhaustible natural resources and phenomena. At attention can take also environmentally friendly and economical.

The energy of sunlight

Solar energy is an affordable alternative that can successfully replace conventional energy sources that pollute the air and water. Interesting fact: almost twenty days of sunshine is equal to all reserves of oil, coal and other fuels. This type of energy is based on conversion of electromagnetic solar radiation into electrical or thermal energy. In fact, the work of the panels is quite clear and simple. Rooted this technology in 1839 when a scientist from France has discovered an electric spark produced when struck with sunlight separate materials. This phenomenon was called the photoelectric effect. Any panel consists of cells, components of which are:

• layers of semiconductor, which are often composed of silicon;

• doped bromine;

• doped phosphorus.

I must say, each cell produces a small amount of energy. For this reason, they assembled in large panels to give more impressive results. It should be noted that the movement towards solar energy brings people many benefits.

Proliferation is stimulated by the affordable price. The demand due to this growing approximately 25% annually. The efficiency increases.

It is necessary to mention and perovskite, which has contributed to the cheapening of solar energy. It gives a chance to reduce the cost of electricity production. Its main feature is that it is able to convert into electricity an impressive amount of sunlight.

Wind energy

Wind energy is the power sector, specializing in converting the kinetic energy of air masses in the atmosphere in the electrical, thermal and any other form of energy for use in agriculture. The transformation occurs with the help of the wind turbine (to generate electricity), wind mills and many other types of units. Wind energy is a consequence of the activities of the sun, so it relates to renewable energy. The power of the wind turbine depends on the area, covered by the blades of the generator. The most promising sites for energy production from wind are considered to be coastal zone. In the sea, at a distance of 10-12 km from the coast (and sometimes beyond), construction of offshore wind farms. The towers of wind turbines mounted on foundations of piles, hammered to a depth of 30 meters. Wind generators practically do not consume fossil fuels. Operation of the wind turbine 1 MW for 20 years of operation allows to save about 29 thousand tons of coal or 92 thousand barrels of oil. The obvious advantage of wind energy is the actual infinity of resources: while the planet has a atmosphere and the Sun is shining, there will be movement of air masses, which can be used for energy. Another definite plus: environmentally friendly. Wind farms do not emit any harmful substances, do not pollute the environment. The advantages of wind power can be attributed to the speed of construction of wind turbines: even for industrial installation requires no more than two weeks. Along with this advantage, as the inexhaustibility of the energy source, there is a disadvantage: the efficiency of wind power depends on the time of year, time of day, weather conditions and geographic location.

The energy of the tides

Power plants of this type are a special type of hydropower that uses tidal energy. Tidal power plants are built on the shores of seas, where the gravitational forces of the moon and Sun twice a day change the water level. For energy the Bay or estuary block a dam with hydroelectric units, which can operate both in generator mode and in the mode of the pump (for pumping water in the reservoir for subsequent work in the absence of tides). In the latter case they are called pumped storage power plant. Advantages of tidal power plants are environmentally friendly and low-cost energy production. Disadvantages — high cost of construction and changing during the day power, causing a tidal power plant may operate only in the unified power system with other types of power plants.

The energy of the waves

Wave power plants use the potential energy of the waves, which is transported on the surface of the ocean. Compared to wind and solar energy wave energy has a higher power density. Despite the similar nature with the energy of the tides, tides and ocean currents wave energy represents a different source of renewable energy.

Geothermal energy

Geothermal energy is a type of energy based on the production of electric energy due to the energy contained in the bowels of the earth, geothermal plants. Usually refers to alternative sources of energy using renewable energy resources. In volcanic regions of circulating water is overheated above the boiling point at relatively shallow depths and fractures rises to the surface, sometimes manifesting itself in the form of geysers. Access to the underground warm water with deep drilling. More than preterm common dry high-temperature rocks, the energy of which is available with the injection and subsequent selection of them hot water. High horizons of rocks with temperature less than 100 °C are common and many geologically inactive territories, because most promising is the use of geothermal energy as a heat source. Commercial application of geothermal springs is common in Iceland and New Zealand, Italy and France, Lithuania, Mexico, Nicaragua, Costa Rica, the Philippines, Indonesia, China, Japan, and Kenya. The main advantage of geothermal energy is its practical neissyakaemoi and complete independence from the environmental conditions, time of day and year. There are the following basic possibilities of using the heat of earth depths. Water or mixture of water and steam, depending on their temperature can be sent for hot water and heating, for electricity generation or for all these purposes. High temperature heat allowances area and dry rocks it is preferable to use to generate electricity and heat. The source of geothermal energy is used depends on the device station. If in this region there are sources of underground thermal waters, it is advisable to use them for heating and hot water. For example, it is estimated that in Western Siberia there is an underground sea with an area of 3 million m2 with water temperature of 70-90 °C. the Main problems that arise in the use of underground thermal waters is the need revolving cycle of receipt (injection) water (usually waste) in the underground aquifer. In thermal water contains large amounts of salts of various toxic metals (e.g., boron, lead, zinc, cadmium, arsenic) and chemical compounds (ammonia, phenols), which eliminates the discharge of such water into the natural water system located on the surface. Of most interest are the high temperature of thermal water or steam outlets that can be used to produce electricity and heat.

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