Offshore Wind Power

Although offshore wind power started late, the world's first true offshore wind farm started in Denmark in Europe. It is marked by the Danish Vindeby offshore wind farm, which was put into operation in 1991. The development of offshore wind power has a history of 27 years. The Vineby wind farm consists of 11 450kW wind turbines, and the unit is only 1.5-3kM away from the coastline. Relying on the stability of sea wind resources and the characteristics of large power generation, offshore wind power has been developing rapidly around the world in recent years. At present, the newly added wind turbine capacity has generally reached 6-8MW, and the installed capacity is tens of kilometers from the coastline. At the same time, most of the developed regions in the world are located in coastal areas, and there is a large demand for power energy. The development of offshore wind power can shorten the distance of power transmission and reduce grid investment and losses. With the development of the economy, people have begun to study offshore wind power, and there have been installed types such as gravity type, single pile type, caisson type, jacket type and floating type. As technology matures and costs decrease, offshore wind power has entered a relatively rapid development period.

In 2018, the world's new onshore and offshore wind power installed capacity was 45.4GW and 4.3GW, respectively, and the cumulative global offshore wind power installed capacity reached 23GW. The Chinese market ’s new onshore and offshore wind power installed capacity were 19.3GW1.7GW. The rapid growth of China's offshore wind power in 2016, the cumulative installed capacity of offshore wind power in 2018 has reached 4.49GW. Europe's offshore wind power technology is leading and developing rapidly, and has always occupied a dominant position in the offshore wind power field. In 2018, a total of 15 new offshore wind farms were launched in Europe, with a new installed capacity of 2.6GW, bringing the total installed capacity in the region to 18.5GW. The United Kingdom and Germany together accounted for 85% of last year's new capacity, 1.3GW and 969MW, respectively. At present, the UK has maintained its market leading position in offshore wind power. In 2018, the cumulative installed capacity was 7.13GW, accounting for 31% of the global installed capacity, followed by Germany, with the cumulative installed capacity of 6.32GW, ranking second in the world, accounting for 27.5%. China ranks third globally with 4.49GW, accounting for 19.5%. 

At present, offshore construction technologies such as large-diameter single piles are relatively mature, and large-scale offshore wind farms have been constructed. According to literature reports, the average size of European offshore wind farms in 2017 reached 453MW, and the average size in 2018 reached 593MW. At present, the total installed capacity reaches 659 WM, and 87 wind turbines are installed. The world's largest single offshore wind farm is completed at the British WalneyExtension wind farm. The Danish offshore wind power company rsted (formerly East Energy) with an installed capacity of 1.2GW HornseaProjectOne offshore wind farm has begun construction in the United Kingdom. The wind farm is 120km from the coast and covers an area of 407km. It is expected to install 174 wind turbines. The intensive effect can reduce the construction cost, operation and maintenance costs of wind farms, and further promote the reduction of power generation costs. Scale-up will be a development trend of offshore wind power.

The first wind farm in the world is only 1.5-3kM away from the coastline. In order to obtain a greater degree of contact with the sea wind, offshore wind power facilities are developing in the direction of deeper seas. 12.7Km and water depth of 12.2 meters. In 2011, the distance was 23.4Km and 22.8 meters. In 2015, the distance was 43.3km and the water depth was over 30 meters. Hornsea is 120 kilometers from the coast of Yorkshire, and offshore wind power is developing offshore. In addition, larger wind turbine blades and more complex floating platforms will inevitably make the construction of offshore wind farms extend to the distant seas. In the distant seas, wind power is greater and power generation is higher.

The offshore conditions are complicated, the wind and waves are large, and the climate is changeable. Therefore, the initial engineering cost of offshore wind power is much higher than that of onshore wind power, and offshore foundation construction and hoisting requirements are high. When constructing at sea, the cost of hoisting a ship is high, and it is charged according to time. It is best to load as much as possible at one time and try to complete it at one time. As a result, offshore wind turbines are becoming larger and more powerful. Forty 87 wind turbines installed in the British WalneyExtension wind farm have 40 MHIVestas8MW wind turbines. The world's largest fan SG10.0-193DD developed by Siemens Gemeifeng has a power of 10MW and a blade length of 94 meters. 

The large-scale offshore wind power has put forward new requirements for the lightweight of the blades, so the application prospect of carbon fiber composite materials in offshore wind power is better.

China has abundant offshore wind power resources, with a coastline length of more than 18,000 kilometers. The wind energy reserves that can be developed and utilized offshore are 750 million kilowatts, which is three times the amount of onshore wind energy resources, and has a broad prospect for development. The wind speed in the southeast coast of China, the Shandong Peninsula and the Liaodong Peninsula and its adjacent islands, northern Inner Mongolia and the lower reaches of the Songhua River, and Xinjiang and Gansu can generally exceed 200w / m2, and wind resources are very abundant. According to the results of the census of offshore wind energy resources, China ’s installed capacity of wind power at a height of 50 meters in seas with a water depth of 5-25 meters is about 200 million kilowatts, and offshore wind power development potential at a depth of 50-50 meters and a height of 70 meters is about 500 million kilowatts.

Starting from the 1.5mw experimental unit of CNOOC Bohai Drilling Platform in 2007, China's offshore wind power has begun. The Shanghai Donghai Bridge wind farm has a total installed capacity of 102mw. It is the world ’s first offshore wind farm outside Europe and China ’s first national offshore wind power demonstration project. The project began hoisting on March 20, 2009, and June 8, 2010. All installation and commissioning are completed and grid-connected power generation. By 2018, China ranks third in the world with 4.49GW, accounting for 19.5%.

China's coastal areas are at the forefront of reform and opening up, with developed economies, and GDP accounts for more than 60% of our country. Energy shortages and shortages in coastal areas have always existed. For this reason, the country has invested a lot of money in the construction of power transmission projects from west to east, or has built more thermal power plants in the east. However, during peak summer power consumption, power is still often limited, and sometimes for the protection of civilians, some companies shut down production in summer. However, the West-East Power Transmission Project is large and the power loss is high, and the pollution caused by coal-fired thermal power cannot be ignored. Therefore, the development of offshore wind power is extremely important to improve China's energy structure. At the same time, the development of offshore wind power has also improved China's industrial structure and technological capabilities. At present, Shanghai Electric, Vision Energy, Goldwind Technology, and Mingyang Smart Energy rank third to sixth in the world for wind power generator manufacturers. Moreover, it has cultivated blade manufacturers such as Sinoma, Zhongfu, Shuangrui, and wind power hoisting ships and other components and installation equipment manufacturers such as Shanghai Zhenhua Heavy Industry. At the same time, many companies with offshore exploration, construction and operation have emerged, forging and training a number of technical teams. This has laid an important foundation for our country to move from a land country on the yellow land to a maritime country on the blue sea.