Summary of wind power
Wind energy is a clean, renewable energy source that is the kinetic energy generated by the flow of large amounts of air on the Earth’s surface. After the surface of the earth is shinning in the sun, different temperatures and different humidity are generated in various places, causing differences in the pressures in various places. In the horizontal direction, high-pressure air flows to the low-pressure area, that is, wind is generated. Wind energy is one of the oldest and most important energy sources on the planet.
Compared with other renewable energy sources, wind energy has the following advantages:
- Compared with solar energy, wind energy has the advantages of low cost and large-scale grid-connected power generation. Solar power generation equipment is large and costly, and it is 6 to 10 times that of wind power generation. The high cost makes it difficult for solar power generation to be put into large-scale grid connection.
- Compared with water energy, wind energy reserves are more abundant, and there is no need to build a dam to drive the turbine.
- Compared with nuclear energy, wind energy does not require expensive equipment and protective equipment, and there are no problems in the acquisition and handling of raw materials, which is more secure and stable.
- Compared with biomass energy, wind energy is taken locally; while biomass energy resources are dispersed, and the cost of fuel collection, storage, and transportation is high, the fuel calorific value is low, and the depreciation rate is high, resulting in higher biomass power generation costs.
As a non-polluting and renewable high-efficiency clean new energy source, wind energy is receiving more and more attention. All countries in the world are stepping up the development and utilization of wind energy. It is estimated that the wind energy reserves that can be developed and utilized globally amount to 20 billion kW, which is 10 times larger than the total amount of water energy that can be developed and utilized globally. In the current situation of depleted fossil energy and serious pollution of the ecological environment, it has become a hot spot for global energy development and utilization.
The usage of wind power
The use of wind energy mainly are using wind as power and wind power generation, wind power generation is the main one. Using wind as power is mainly used for windsurfing, windmill lifting, wind heating.
Wind power generation
Wind power generation began in Denmark. The government developed a wind power plan in 1890 and subsequently built the world’s first wind power station. By 1918, there were 72 wind turbines with a stand-alone power of 5 to 25 kW.
In 1941, the United States produced a wind turbine with a power of 1,250 kW, but it was limited to the technical level at that time, unstable operation, low economical efficiency, and stopped running after nearly four years of operation due to strong wind blown-off blades.
After the Second World War, economic recovery and insufficient energy prompted some industrialized countries to develop medium-sized and large-scale wind power generator.
Denmark has developed wind power generator of 45 kW and 200 kW, which are put into operation after being put into operation. Germany made a 100 kW wind power generator in 1955. After the 130 kW wind power generator was built in 1950, the 800 kW wind power generator was built in 1958.
However, under the impact of cheap oil and fossil fuel generators, these experimental wind power generator were suspended.
The oil crisis occurred in 1973 and with the deterioration of the global environment, wind power was re-emphasized.
In the 1980s, the development of horizontal-axis wind power generator with a single unit capacity of more than 100 kW developed rapidly in Europe and the United States.
In 1987, the United States developed a horizontal-axis wind power generator with a single unit capacity of 3.2 MW.
Denmark, Germany, the Netherlands, Spain and other countries have also developed wind power generator of more than 100 kW.
At the same time, in order to solve the problem of instability and small capacity of wind power generator output power, a system in which a large number of wind power generator are installed in the same site and power is supplied to the grid is adopted.
This type of system is called a wind farm.
Large-scale wind farms are now widely built in countries all over the world. In addition to the construction of onshore wind farms, offshore wind farms are being built to obtain richer and more powerful offshore wind energy.
Studies have shown that for every doubling of wind power capacity, its cost will drop by 15%.
In recent years, the global wind power growth rate has remained at 30%, wind power costs have fallen rapidly, and in developed countries, it is close to the cost of coal-fired power generation.
Because wind power is both clean and economical, more than 50 countries around the world are working hard to research and develop wind power.
European countries with abundant wind resources are stepping up their efforts in wind power development and research. By the end of 2004, Germany’s wind power generation was about 6.2% of the country’s total power generation, and it is planned to increase to 50% by 2050. Danish wind power accounts for 20% of its total electricity.
An international energy research report shows that by 2020, global wind power can provide 12% of global electricity demand, reducing CO2 emissions by more than 10 billion tons.
In addition, the United States also plans to use wind power to account for 30% of its total installed capacity by 2030.
With the depletion of fossi fuel and rising prices, the cost of thermal power generation will gradually increase, and the cost of wind power will continue to decline as the capacity of wind turbines increases and the scale of wind farms expands. Therefore, wind power is the most promising renewable energy source in the near future and in the future. Its rapid development is an inevitable trend.
Other usage of wind power
The first way humans use wind energy is to sail.
Egypt is the first country to use wind energy. About 5,000 years ago, Egyptian sailboats sailed on the Nile. Since then, with the advancement of sailing manufacturing technology, the development of science and technology and the accumulation of navigation experience. Windsurfing has ushered in a brilliant 15th century – Age of Discovery. Columbus took a sailing boat and discovered the New World of the Americas during this period. But with the invention of steam engines and internal combustion engines and the large-scale exploitation and utilization of ore energy such as coal and oil, sailing boats have been gradually eliminated due to their small power and slow speed.
But after the oil crisis of 1973, it was re-emphasized.
In 1980, Japan built the world’s first modern sailboat, “Shin Aitoku Maru”. The vessel has a capacity of 1,600 tons and a displacement of 2,400 tons. It is equipped with a two-sided roll-type fiber reinforced plastic sail and a low-speed diesel engine as auxiliary power. The sails use wind energy to power the ship, thus saving fuel. Compared with ordinary motor boats of the same load, this ship can save 50% of fuel, but the transportation time is increased by 20%. Modern sails are controlled by computers, allowing the sail to rotate as much as possible to maintain optimal wind utilization.
In 2007, a kite-assisted ship, the “Beluga SkySails”, was built in Germany and put into navigation. In addition to the conventional power system, the ship also installed a giant kite with an area of 160 m2 . A mast that is fixed to the bow and automatically retractable sends the kite to a height of 300 m to take advantage of the stable and strong winds of the sea to navigate the vessel. The kite is made of ultra-light synthetic fibers. At wind speeds up to 13 km/h, the kite provides the ship with four times the power of a conventional sail. The engine on board can be fully enclosed. During normal navigation, the computer directs the kite in different directions according to the wind and wind direction, reducing the engine load of the ship.
Besides, there is also the flettner rotor, Invented by the German aerospace scientist Anton Flettner in 1920, the “E-Ship1” built by this technology in 2010 has already had 13,000 gross tons, DNVGL class, all electric configuration.
The role of wind-heating is to convert wind energy into heat for home or industrial and agricultural heating needs.
There are usually three conversion methods.
- Use a wind power generator to generate electricity, and then heat the electricity into the resistance wire. This is an indirect heating method and the conversion efficiency is not high.
- Use a wind power generator to drive an air compressor to compress the air and release heat. This method is not efficient.
- Drive the wind power generator directly through the actuator to drive the agitator at high speed and stir the liquid to heat up. This method has the highest conversion efficiency.
In addition, it is also an effective method to use wind to rub solid materials to generate heat.
Early In 1981, Japan used wind-heating methods to raise squid in Hokkaido and used it in greenhouses in Kyoto and other places.
Wind heaters are also used in home heating in Denmark, Netherlands, the United States, and New Zealand.
This is an effective measure to save energy and improve people’s living standards. Countries such as Europe, America and Japan are further developing this aspect.
Wind lifting can be used for water lifting operations in irrigation of farmland, drinking water for humans and animals, salt making in seawater, aquaculture, pasture improvement or shoal renovation, with significant economic and social benefits.
The overall working principle of the wind-pumping machine is to apply the transmission mechanism to the shaft movement of the wind power generator due to the wind to convert it into vertical movement or vertical rotation speed, so as to drive the piston pump connected thereto. Or a rotary water pump.
The future of wind energy
Wind energy is a clean and natural energy source with abundant resources and sustainable regeneration. It is the preferred alternative energy source for ore energy, both in terms of economic principles and technical reliability.
With the innovative development of human science and technology, wind energy will be more widely and efficiently applied to people and benefit the people.