Contents
Introduction. 3
History of wind energy. 4-5
Modern methods of generating electricity from wind energy. 5-6
Statistics on the use of wind power 6-7
Environmental aspects of wind energy. 7-9
Radiointerference. 10-20
Vocabulary. 32
References. 33
Introduction
Wind energy - the energy industry, specializing in the transformation of air masses in the atmosphere of the kinetic energy into electrical, mechanical, heat or any other energy form suitable for use in the national economy. This transformation can be carried out by such units as the wind generator (to produce electricity), a windmill (for conversion into mechanical energy), the sail (for use in transport), and others.
Wind energy is a renewable forms of energy, as it is a consequence of solar activity. Wind energy is a booming industry. By the beginning of 2016 the total installed capacity of all wind generators was 432 gigawatts [1], and thus exceeded the total installed capacity of nuclear power (but in practice, the average annual capacity of wind power is several times lower than the installed capacity, while nuclear power is almost always running the installed power mode). In 2014, the amount of electrical energy that is produced by all wind turbines of the world amounted to 706 terawatt-hours (3% of the produced electric energy by mankind). Some countries especially intensively develop wind power, in particular, in 2015 in Denmark by means of wind turbines produced 42% of all electricity; 2014 Portugal - 27%; in Nicaragua - 21%; Spain - 20%; Ireland - 19%; Germany - 8%; in the EU - 7.5% [3]. In 2014, 85 countries used wind energy on a commercial basis. At the end of 2015, the wind industry employs more than one million people worldwide (including 500,000 in China and 138,000 in Germany).
Large wind farms are included in the overall network, the smaller are used for electricity supply of remote areas. Unlike fossil fuels, wind energy is practically inexhaustible, widely available and more environmentally friendly. However, the construction of wind power is associated with some difficulties of technical and economic nature, slowing down the spread of wind power. In particular, the volatility of wind flow is not a problem with a small proportion of wind energy in total electricity production, but with an increase in this proportion, increase also the problem of the reliability of electricity production. To solve these problems using intelligent management of electricity distribution.
History of wind power
Windmills were used for grinding grain in Persia in the year 200 BC. e. Mills of this type are common in the Islamic world and in the XIII century brought to Europe by the Crusaders.
Mill on the box, the so-called German mills were to the middle of the XVI century the only known. Strong storm could overturn a windmill with bed. In the middle of the XVI century, Fleming found a method by which it makes it impossible to mills rollover. At the mill he set only the roof of the mobile, and to rotate the wings of the wind, it was necessary to turn only the roof, while the mill building itself was strongly fortified on earth.
- Marx machines: application of the forces of nature and science.
gantry mill mass was limited due to the fact that it had to be rotated manually. So it was limited and its performance. Improved mill are called tent.
In the XVI century in Europe's cities are beginning to build a water pumping station with hydraulic and windmill Toledo - 1526, Gloucester - 1542, London - 1582, Paris - 1608, and so on.
In the Netherlands, many windmills pumped water from the land, enclosed by dikes. Reclaimed sea land used in agriculture. In arid areas of Europe windmills used for irrigation.
Windmills producing electricity, was invented in the XIX century in Denmark. There's first wind power plant was built in 1890, and by 1908 there were already 72 stations with capacity from 5 to 25 kW. The largest of them had a height of 24 m tower and a four-blade rotor diameter of 23 meters. The predecessor of the modern wind power plants with a horizontal axis was 100 kW and was built in 1931 in Yalta. It had a tower 30 meters high. By 1941, the unit capacity of wind power reached 1.25 mW.
In the period from the 1940s to the 1970s, wind energy is experiencing a period of decline due to the intensive development of the transmission and distribution networks, provide an independent power supply from the weather for reasonable money.
The revival of interest in wind energy began in 1970 after the 1973 oil crisis. The crisis has demonstrated the dependence of many countries on imported oil and has led to the search for options to reduce this dependence. In the mid-1970s in Denmark began testing the predecessors of modern wind turbines. Later Chernobyl accident also stimulated interest in renewable energy sources. California has implemented one of the first programs to stimulate wind power, began providing tax incentives for producers of electricity from wind.
Modern methods of generating electricity from wind energy
Power wind turbine depends on the area, the swept generator blades, and the height above the surface. For example, turbines with capacity of 3 MW (V90) Vestas Danish production company has a total height of 115 meters, a height of 70 m tower and blade diameter of 90 meters.
Air flow near the ground / sea is turbulent - the underlying layers located above the brake. This effect is noticeable up to a height of 2 km, but drops sharply at heights beyond 100 meters. The height above the generator of the surface layer at the same time can increase the diameter of the blades and frees space on the ground for other activities. Modern generators (2010) have already reached this milestone, and their number is rapidly growing in the world. Wind turbine begins to produce current when the wind 3 m / s and turns off when the wind more than 25 m / s. Maximum power is reached at a wind of 15 m / s. Output power is proportional to the third power of the wind speeds: if the wind increases twice from 5 m / s to 10 m / s, the power is increased by eight times.
In August 2002, the company built a prototype of the Enercon E-112 wind generator with a capacity of 4.5 MW. Up to December 2004 remained the largest turbine in the world. In December 2004, the German company REpower Systems built its wind turbine power capacity of 5.0 MW. The diameter of the rotor of the turbine of 126 meters, the nacelle weight - 200 tons, the height of the tower -. 120 m In late 2005, Enercon has increased the capacity of its wind turbine up to 6.0 MW. The diameter of the rotor was 114 meters, the height of the tower 124 meters. In 2009, the turbine class 1.5 - 2.5 MW occupied 82% of the world vindenegetike.
In January 2014 the Danish company Vestas started to test the turbine 164 V-8 MW. The first contract for the supply of turbines was signed in late 2014. To date, V-164 - the most powerful wind turbine in the world. Generators are being developed more than 10 MW.
The most widespread in the world got wind turbine design with three blades and a horizontal axis of rotation, although in some places there are more and two-bladed. The most efficient design for areas with low speed wind streams are recognized wind turbines with a vertical axis of rotation, ie. N. rotary or carousel. Now more and more manufacturers are moving to the production of such plants, since not all consumers living in coastal and inland wind speed generally ranges from 3 to 12 m / s. This vetrorezhime efficiency vertical installation is much higher. It should be noted that vertical wind turbines have several significant advantages: they are practically silent, and do not require absolutely no maintenance, a service life of over 20 years. braking systems developed in recent years, ensures stable operation even with periodic squall gusts up to 60 m / s.
Statistics on the use of wind power
By the beginning of 2015 the total installed capacity of all wind turbines was 369 Gigawatt. The average increase in the amount of wind power in the world, since 2009, is 38-40 gigawatts per year and due to the rapid development of wind power in the United States, India, China and Germany.
Worldwide, in 2008, more than 400 thousand people were employed in the wind energy industry. In 2008 the world market of equipment for wind energy grew to 36.5 billion euros, or about 46.8 billion US dollars.
In 2010, 44% of the installed wind power has been concentrated in Europe and Asia - 31%, in North America - 22%.
In 2014, 39% of electricity in Denmark is produced from wind power.
In 2014, wind power produced in Germany, 8.6% of the total energy produced in Germany.
In 2009, China's wind power produces about 1.3% of the country's electricity. In China, the law on renewable energy sources in 2006. It is expected that by 2020 wind power capacity will reach 80-100 GW.
In December 2014, wind energy has provided 164% of the electricity consumed by households in Scotland. October 28, 2013 the Danish wind turbines produced 122 percent of the electricity consumed. Portugal and Spain on certain days of the 2007 Energy wind generated about 20% of electricity. March 22, 2008 in Spain from wind energy was generated 40.8% of the country's electricity.
Environmental aspects of wind energy
Emissions
Wind turbines of 1 MW reduces annual emissions of 1,800 tons of CO2, 9 tons of SO2, 4 tons of nitrogen oxides.
According to estimates Global Wind Energy Council in 2050 the global wind power will reduce annual CO2 emissions by 1.5 billion tons.
The impact on the climate
Wind withdraw part of the kinetic energy of a moving air mass that reduces the velocity of their movement. With mass use of wind turbines (eg, in Europe), this slowdown could theoretically have a noticeable impact on the local (and even global) climate areas. In particular, the decrease in the average wind speed is able to make the climate of the region a little more continental due to the fact that the slow-moving air masses more time to warm summers and cool winters. Also, removal of energy from the wind can contribute to changing humidity conditions of the surrounding area. However, scientists have so far only deploy research in this area, studies that analyze these aspects do not provide a quantitative assessment of the impact of large-scale wind energy on the climate, however, suggest that it may not be as negligible as previously thought.
According to the modeling of Stanford University, a large offshore wind farm could significantly weaken hurricanes by reducing the economic damage from their impacts.
Noise
Wind power plants produce two kinds of noise:
mechanical noise - the noise from the operation of mechanical and electrical components (for modern wind turbines is virtually absent, but it is significant in the older models of wind turbines)
aerodynamic noise - the noise from the interaction of wind flow by installing blades (increases with the passage of the blades passing the tower wind turbine)
Currently, in determining the level of noise from wind turbines use only the calculation method. The method of direct measurements of the noise level does not give information about wind turbine noise, as efficient separation of noise from wind turbines wind noise at the moment impossible.
In the vicinity of the wind turbine at the axis of the propeller noise is sufficiently large wind turbines may exceed 100 dB.
An example of such a wind turbine design miscalculations Grovian. Due to the high level of noise installation worked about 100 hours and was dismantled.
Laws passed in the UK, Germany, the Netherlands and Denmark, to limit the noise level of the operating wind power plant of up to 45 dB in the daytime and 35 dB at night. The minimum distance from the installation to residential homes - 300 m.
Low-frequency vibration
Low-frequency vibrations transmitted through the ground, causing significant bounce in glass houses at a distance of 60 m from the megawatt-class wind turbines.
Typically, homes are located at a distance of not less than 300 m from the wind turbine. At this distance, the contribution of wind power in the infrasonic oscillations can no longer be isolated from background fluctuations.
Icing blades
During operation of wind turbines in winter when the humidity is high, the formation of ice build-up on the blades. At start-up wind turbines is possible dispersion of ice at a considerable distance. As a rule, the territory in which the cases are possible icing of blades, installed warning signs at a distance of 150 m from the wind turbine.
Furthermore, in the case of lung lobes icing cases improve the aerodynamic profile characteristics were noted.
Visual effects
The visual impact of wind turbines - a subjective factor. To improve the aesthetic appearance of wind turbines in many majors professional designers work. Landscape architects are attracted to the visual study of new projects.
The review carried out by the Danish AKF, the value of exposure to noise and visual perception of wind turbines rated less than 0.0012 euro per 1 kW h. Survey was based on interviews with 342 people living in the vicinity of wind farms. Residents were asked how much they would pay for it to get rid of the proximity to the wind turbines.
Land use
The turbines occupy only 1% of the entire territory of the wind farm. In 99% of the farm may be engaged in agriculture or other activities, which is what happens in such densely populated countries such as Denmark, the Netherlands, Germany. The foundation of wind turbines, ranking about 10 m in diameter, is usually completely underground, allowing to expand the agricultural use of the land almost to the base of the tower. The land is leased, which allows farmers to generate additional income. In the US, the cost of land lease by one turbine is $ 3000- $ 5000 per year.
Damage caused by animals and birds. These AWEA.
The populations of bats living near the windfarm on the order are more vulnerable than the bird population. Near the end of wind turbine blades, a region of low pressure, and a mammal which has got into it, it gets barotrauma. More than 90% of bats found near wind turbines show signs of internal bleeding. According to the explanations of scientists, birds have a different structure of the lungs, and therefore less susceptible to sudden changes in pressure and suffer only from direct collision with the blades of wind turbines.
Use of water resources
Unlike conventional thermal power plants, wind farms do not use water, which can significantly reduce the pressure on water resources.
|
|
|
|
|
|
|
|
|
Radiointerference
Metal construction of wind turbines, especially elements in the blades can cause significant interference to radio reception. The larger the wind turbine, the more noise it may produce. In some cases, to solve the problem have to install additional repeaters.
|
|
|
Summary
Wind power is the use of air flow through wind turbines to mechanically power generators for electric power.
Wind energy is a renewable forms of energy, as it is a consequence of solar activity. By the beginning of 2016 the total installed capacity of all wind generators was 432 gigawatts and thus exceeded the total installed capacity of nuclear power.
Industrial wind set
Comprises:
Foundation
Power cabinet, including contactors and control circuit
Tower
Stairs
indexing mechanism
Gondola
Electric generator
The tracking system for the direction and wind speed (anemometer)
Brake system
Transmission
blades
The system changes the blade angle of attack
Cowl
Power wind turbine depends on the area, the swept generator blades, and the height above the surface.
The most widespread in the world got wind turbine design with three blades and a horizontal axis of rotation, although in some places there are more and two-bladed.
And now we will pay little attention to the impact on the climate.
Wind withdraw part of the kinetic energy of a moving air mass that reduces the velocity of their movement. With mass use of wind turbines (eg, in Europe), this slowdown could theoretically have a noticeable impact on the local (and even global) climate areas. In particular, the decrease in the average wind speed is able to make the climate of the region a little more continental due to the fact that the slow-moving air masses more time to warm summers and cool winters.
Translation of the abstract
, , , , . , ( ), ( ), ( ) .
, . . 2016 432 [1] , , ( , ). 2014 , , 706 - (3 % ). , , 2015 42 % ; 2014 27 %; 21 %; 20 %; 19 %; 8 %; 7,5 %[3]. 2014 85 . 2015 1 000 000 ( 500 000 138 000 ).
, . , , . , , . , , , . .
