1. History of World Wind Energy Development and Utilization
The history of human use of wind energy can be traced back to BC. In foreign countries, in the 2nd century BC, the ancient Persians used vertical-axis windmills to mill rice. In the 10th century, the Islamic people used windmills to lift water. In the 11th century, windmills have been widely used in the Middle East. Windmills spread to Europe in the 13th century, and they have become an indispensable prime mover in Europe in the 14th century. In the Netherlands, windmills were first used to draw water from lakes and low wetlands in the Rhine Delta, and later for oil extraction and sawing. Only because of the appearance of the steam engine, the number of windmills in Europe dropped sharply.
Wind power generation first started in Denmark. Its government formulated a wind power generation plan in 1890, and subsequently built the world's first wind power station. By 1918, there were 72 wind turbines with a single power of 5-25kW. Now Denmark has more than 3,000 wind turbines, generating 10 billion kWh of electricity annually. In 1931, the former Soviet Union successfully manufactured a 30kW horizontal axis wind turbine. It was the most powerful one in the world at that time. In 1941, a wind turbine with a power of 1250kW was trial-produced in the United States. However, it was limited to the technical level at that time, and its operation was unstable and economical. After nearly 4 years of operation, the blades were broken due to strong winds and stopped operating. After the Second World War, economic recovery and energy shortages prompted some industrially developed countries to restart the development of medium and large wind turbines. Denmark has developed wind turbines such as 45kW and 200kW, which will be integrated into the power grid after being put into operation. Germany made a 100kW wind turbine in 1955. After France made a 130kW wind turbine in 1950, it also made an 800kW wind turbine in 1958. But under the impact of cheap oil and fossil fuel generator sets, these experimental wind turbines have all been suspended.
With the oil crisis in the West in 1973 and with the deterioration of the global environment, wind power generation has received renewed attention, and various countries have stepped up the research and development of wind turbines. The United States began implementing the Federal Wind Energy Program in 1974. The main contents are: assess the country’s wind energy resources; study the social and environmental issues in the development of wind energy; improve the performance of wind turbines and reduce the cost; mainly study wind turbines less than 100kw for agriculture and other users; for power companies and industries User-designed megawatt-level wind turbines. In the 1980s, the development of horizontal-axis wind turbines with a single unit capacity of more than 100kW developed rapidly in Europe and the United States. In 1987, the United States developed a horizontal-axis wind turbine with a single-unit capacity of 3.2MW. Countries such as Denmark, Germany, the Netherlands, and Spain also developed wind turbines with a capacity of more than 100kW. In the 1980s, the United States also successfully developed 6 types of wind turbines of 100, 200, 2000, 2500, 6200, and 7200kw. At present, the United States has become the country with the largest installed capacity of wind turbines in the world, with more than 20,000 MW, and an annual growth rate of 10%. Now the world’s largest new type of wind turbine has been built and put into operation on the island of Hawaii. Its wind turbine blade diameter is 97.5m and weighs 144t. The wind angle adjustment of the wind wheel and the operation of the unit are controlled by a computer, and the annual power generation capacity is 10 million kw. ·H. According to the statistics of the U.S. Department of Energy, wind power in the U.S. accounted for 1% of the total power generation in 1990. In Sweden, the Netherlands, the United Kingdom, Denmark, Germany, Japan, and Spain, corresponding wind power generation plans have also been formulated in accordance with the conditions of their respective countries. For example, in 1990, the installed capacity of wind turbines in Sweden reached 350MW, with an annual power generation of 1 billion kw·h. Denmark built the Jutland wind power station in 1978 with an installed capacity of 2000kw, the sweeping diameter of three blades is 54m, and the height of the concrete tower is 58m. It is estimated that 10% of the electricity demand in 2005 will come from wind energy. Germany built a wind power station at the mouth of the Elbe in 1980, with an installed capacity of 3000kw, and wind power will account for 8% of the total power generation by the end of this century. In the United Kingdom, the British Isles are close to the ocean, and the wind energy is very rich. The government also attaches great importance to wind energy development. By 1990, wind power accounted for 2% of the total electricity generation in the UK. In Japan, in October 1991, the largest wind power station in Aomori Prefecture of the Kazu Strait was put into operation. Five wind turbines can provide electricity to 700 households.
In order to solve the problem of the instability and low capacity of the output power of wind turbines, some countries have adopted a system that installs a large number of wind turbines on the same site and jointly supplies power to the grid. This kind of system is called wind farm, or wind farm for short. Currently, large-scale wind farms are widely established in various countries. In addition to building onshore wind farms, offshore wind farms are also being built to obtain more abundant and powerful offshore wind energy. A wind farm is to install a number of large-scale grid-connected wind turbines on sites with good wind energy resources. They are arranged in an array according to the terrain and main wind direction to form a cluster to supply power to the grid. Wind turbines are arranged on the ground like crops, so they are vividly called "wind fields". Wind farms emerged in California in the early 1980s. The largest wind farm in the world is the Tehachapi Wind Farm near Los Angeles, with an installed capacity of more than 500,000 kilowatts and an annual power generation of 1.4 billion kilowatt-hours. , Accounting for about 23% of the world's total wind power generation.
Wind power does not release carbon dioxide, does not cause acid rain and pollute the atmosphere, land and water sources, so it is the preferred method to replace conventional fossil fuel-fired power plants. At the same time, it is also an economical and quick-acting measure to significantly reduce carbon dioxide emissions. 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 been maintained at 30%, so the cost of wind power has dropped rapidly, and it is close to the cost of coal-fired power generation abroad. Because wind power is 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 increasing the development and research of wind power.
One of the world’s largest horizontal-axis wind turbines is currently a 5MW wind turbine developed by Germany. A wind farm with 200 such wind turbines can generate electricity equivalent to that of a large conventional coal-fired power station of 1 million kW. Since wind energy is a clean energy source, the former can emit 1 million tons of smoke and dust (dust, Co, etc.) less than the latter, 630 kg of benzostilbene, a strong carcinogen, and CO2, a gas that causes a large amount of greenhouse effect. Its environmental protection and economic benefits are very significant. The super-large 5MW three-blade wind turbine has a wind wheel diameter of 125m and a wind wheel area of 12000m², which is equivalent to the area of two football fields. The wind turbine and nacelle weigh hundreds of tons and are placed on a tower 120m high. The power generation of this unit alone can provide electricity for 6000 households. Germany's wind power generation by the end of 2004 was about 6.2% of the country's total power generation. It has been planned to increase to 12.5% by 2010 and 50% by 2050. A report by the European Wind Energy Association indicates that by 2020, 20% of Europe's electricity will use wind power. At present, Danish wind power accounts for 20% of its total electricity. Another international energy research report of the association shows that by 2020, global wind power can provide 12% of global electricity demand and reduce carbon dioxide emissions by more than 10 billion tons. In addition, the United States also plans that by 2030, wind power will account for 30% of its total installed power capacity. With the depletion of fossil fuels 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. According to United Nations estimates of new energy and renewable energy, the cost of wind power generation can be reduced to 3 cents/kWh or less by 2020. Therefore, wind power is the most promising renewable energy in the near future and in the future, and its rapid development is an inevitable trend.
China is one of the first countries in the world to use wind energy. In the centuries BC, the Chinese people used wind to lift water, irrigate, grind flour, spring rice, and use sails to propel ships forward. In the Song Dynasty, it was the heyday of windmills in China. The vertical axis windmills that were popular at that time have been in use today.
China has a history of using windmills at least not later than the middle of the 13th century. Various forms of simple windmills have been built for rice milling, water extraction, and salt production. Until the 1950s, "revolving lantern" windmills were still visible. The development of wind turbines in China was the canopy windmills of various wooden structures at the end of the 1950s. In 1959, there were more than 200,000 wooden windmills in Jiangsu Province alone. By the mid-1960s, the main focus was on the development of wind pumps. After the mid-1970s, the development and utilization of wind energy was included in the "sixth five-year plan" national key project, and it has developed rapidly.
China's wind power generation industry first started in the 1970s, and it was originally mainly to solve the urgent demand for electricity in rural areas, pastoral areas, and islands far away from the power grid. Therefore, it focuses on the research and development of 100~1000W independently operated off-grid small wind turbines, and has achieved obvious economic and social benefits. At present, the production capacity and annual output of off-grid small wind turbines rank first in the world. In addition to meeting the needs of Chinese users, they are also exported abroad.
In the 1980s, China began to include the research and development of large-scale wind turbines as a national scientific and technological research project, organized Chinese scientific and technological forces and enterprises to jointly tackle key problems, and introduced foreign units on the other. Since the mid-1980s, China has successively introduced a batch of medium and large wind turbines from Denmark, Belgium, Sweden, the United States, and Germany, digested and absorbed them, mastered the manufacturing technology of large-scale wind turbines, and assembled or co-produced them. Eight demonstration wind farms have been established in the tuyere of Xinjiang and Inner Mongolia and the islands of Shandong, Zhejiang, Fujian and Guangdong. From 1985 to 1995, it successively developed 120kW, 200kW and 300kW wind turbines. The installed capacity in 1992 has reached 8MW. The installed capacity of the wind farm in Dabancheng, Xinjiang has reached 3300kw, which is currently the largest wind farm in the country. By the end of 1990, the irrigated area of wind pumped water nationwide had reached 25,800 mu. Between 1995 and 2003, 600kW and 750kW fixed-pitch wind turbines were developed, and the localization rate reached more than 90%. In 1997, 100,000 kw of wind power was added. In order to cope with the industrialization of China's large-scale wind turbines, China has gradually formed a professional manufacturer of blades, gearboxes, generators, yaw systems, electronic control systems and other components. In 2005, the self-developed 1.0MW variable speed constant frequency wind turbine was put into operation. In 2006, it successfully developed a variable-pitch variable-speed wind turbine with a power of 1.5MW, marking that the independent innovation capability of China's megawatt-class large-scale wind turbines has reached the world's advanced level. The Chinese cost of this unit is about 7.5 million yuan, and the cost per kilowatt unit is only about 5,000 yuan. This greatly reduces the manufacturing cost of wind turbines and has gradually approached the level of conventional thermal power construction costs of 4,000 yuan per kilowatt.
At present, China has developed more than 100 wind turbines of different forms and capacities, and the wind turbine industry has initially formed. Nevertheless, compared with developed countries, the development and utilization of wind energy in China is still quite backward, not only the development speed is slow, but also the technology is backward, and it is far from being scaled up.
China's "Renewable Energy Medium and Long-term Development Plan Outline (2004~2020)" stipulates that the installed capacity of grid-connected wind power will be 5 million kW by 2010 and 30 million kW by 2020. Therefore, by 2020, China's installed wind power capacity will be 24 times the total installed wind power capacity of 1.26 million kW in 2005, a very rapid growth. The construction of wind farms in China began in 1983. At that time, three Danish 55kW wind turbines were used as demonstration test wind farms for grid-connected wind power generation technology in Rongcheng, Shandong. By the end of 2005, 61 wind farms had been built across the country with a total installed capacity. The capacity is 1.26 million kW. At the end of 2007, the total installed capacity of wind power reached 4 million kW. It is estimated that the total installed capacity of wind farms will exceed 5 million kW by 2010 and will exceed 30 million kW by 2020. Although wind power has developed rapidly in China, due to its late start, even by 2020, wind power will still account for only about 3% of the country's power generation.
China is rich in wind energy resources, clean and environmentally friendly, and has great potential for development and utilization. With its large-scale development, the progress of wind power innovation technology, the further increase of localization rate and the increasing price of mineral energy due to the increasing depletion, the cost of wind power generation will be lower than the cost of conventional thermal power generation, and therefore will be more large-scale and rapid. developing.
An important stage of China's wind power development
China's wind power generation began in the 1980s, and its development is relatively lagging, but it has a relatively high starting point and has mainly experienced three important development stages.
The first stage: the experimental stage from 1985 to 1995
Use loans from the governments of Denmark, Germany, and Spain to demonstrate some small projects.
Large European wind power countries have used their domestic loans and grants to test their wind turbines in the Chinese market and have accumulated a lot of experience. At the same time, the national "Seventh Five-Year Plan" and "Eighth Five-Year Plan" projects for domestically produced wind turbines have achieved preliminary results.
The second stage: 1995~2003
Based on the results achieved in the first phase, governments at all levels in China have successively introduced various preferential incentive policies. The Ministry of Science and Technology has promoted the development of wind power technology through scientific and technological research and the national 863 high-tech project. The former Economic and Trade Commission and the Planning Commission have respectively promoted the sustainable development of wind power through the Double Plus Project, the National Debt Project, and the Wind Power Project.
The third stage: 2003~present
The National Development and Reform Commission, through wind power franchise management, delegates the approval power for wind power projects below 50,000 kilowatts, requires preferential policies such as the localization ratio of wind power projects in China to not less than 70%, supports and encourages the development of China’s wind power manufacturing industry, and enables China’s wind power market The development of China has entered a stage of rapid development. China’s new installed capacity in 2006 was 1.347 million kilowatts, more than double the previous capacity, and an increase of 70% over 2005. China's current cumulative installed capacity of wind power is 2.604 million kilowatts, making it the sixth largest market in the world. Since the implementation of the New Energy Law on January 1, 2006, the Chinese market has developed steadily in 2006, and this development momentum will be consolidated and accelerated. According to the statistics of approved projects and projects under construction, the installed capacity of wind power will increase by 1.5 million kilowatts in 2007. In 2010, China’s wind power development target is 5 million kilowatts. This target is expected to be achieved and completed ahead of schedule.