China's offshore wind power presses the "fast-forward button", and its installed capacity ranks first in the world——
Riding the wind and waves, the green power of the "blue engine"
Our reporter Liu Leyi
On March 30, under the blue sea and blue sky, the white wind turbines stood tall and the huge paddles turned leisurely, turning the waves of the vast sea into new kinetic energy for social and economic development.
This is the first one million kilowatt-class offshore wind power project in China—the Three Gorges Yangjiang Shapa Offshore Wind Power Project (hereinafter referred to as the "Three Gorges Yangjiang Project") located in the sea area of Shapa Town, Yangjiang City, Guangdong Province.
As of March 25, the project has produced more than 1 billion kWh of electricity, which can replace 307,600 tons of standard coal, which is equivalent to the normal electricity consumption of 500,000 families of three for one year.
In recent years, driven by the global green wave and the "dual carbon" goal, China's offshore wind power "blue engine" is full of power.
In 2021, China's offshore wind power installed capacity will leap to the world's largest, forming a complete wind power industry chain and supply chain with leading level and global competitiveness.
As Li Chuangjun, director of the New Energy and Renewable Energy Department of the National Energy Administration, said: "China's offshore wind power has achieved a major breakthrough from small to large, from weak to strong, from slow development to leapfrog development."
Overcome hardships—
"Towards the blue ocean" becomes a "must answer"
If we want to achieve the "dual carbon" goal, the clean energy business urgently needs leapfrog and differentiated development.
Due to the slowdown in installed capacity growth, the wind power industry, which originally had a first-mover advantage, is facing a situation of being overtaken.
Prospering towards the sea and becoming strong towards the sea, "going to the blue ocean" has become a "must-answer" for the industry to break the situation.
"China must not only develop terrestrial resources, but also move towards the blue ocean and build a maritime power. Offshore wind power can promote scientific and technological progress, industrial upgrading, and drive the development of regional economy. It is a very important industrial chain." said Liu Jizhen, an academician of the Chinese Academy of Engineering.
In fact, in developing offshore wind power, China has natural advantages - a long coastline, a wide area of available sea area, and great room for development.
Wang Wubin, Chairman and Secretary of the Party Committee of the Three Gorges New Energy Company of China Three Gorges Corporation, introduced that the wind power tower stands on the sea, and the foundation engineering on the seabed must be done solidly. The current is conducted to the offshore booster station through the submarine cable buried in the seabed, and then integrated into the power grid in a high-voltage manner, and finally transmitted to thousands of households.
However, the construction of offshore wind power projects is by no means easy.
"Unlike the construction of river dams, offshore wind power construction requires boarding operations, and is basically drifting at sea 24 hours a day." As a veteran with 9 years of offshore wind power work experience, Teng Huadeng, manager of the project management department of the Three Gorges Yangjiang Project, told Our reporter, subject to complex and changeable natural conditions, offshore wind power construction often faces great challenges.
Taking the Yangjiang sea area as an example, the monsoon season is from October to February of the second year, with high winds and waves. In winter, the swell is basically above 2.5 meters, and the highest can reach more than 4 meters. The annual operating weather window is only about 100 days. .
"The average age of our team is only 29 years old, but everyone has a strong thirst for knowledge. They often get together for meetings to optimize the construction plan." Facing the harsh sea conditions, Teng Huadeng led the team to learn and work, actively promote the application of new technologies, and successfully completed the construction. It has built the offshore booster station with the largest single capacity in Asia, and laid the first large-capacity photovoltaic composite submarine cable in China. The Three Gorges Yangjiang Project has become the first offshore wind power project in China to be developed on a large scale.
In addition to the daunting waves of the vast sea, the geological conditions of the seabed are also unpredictable.
"Putting chopsticks on tofu" is the most vivid metaphor for the construction of wind power foundations in the intertidal zone.
"On the muddy tidal flat, the project erection line is sent to the wind power station, and it is often necessary to hoist the work in waist-deep water. This station lasts for most of the day..." Around 2012, a batch of intertidal offshore wind power test field projects were launched. In Rudong County, Jiangsu Province, when looking back on the scene of that year, Qu Cheng, associate director of the Rudong County Power Supply Branch of State Grid Jiangsu Electric Power Co., Ltd., was not without emotion.
At that time, the construction of pile foundations mostly used excavation type line pouring foundations, and the depth of pile foundations was generally about 4 meters.
However, "sea and land" are like "heaven and earth", and it is difficult to fully transfer successful experience from land to sea.
The tidal flat geology is mostly quicksand, and the pile foundation is often laid on the first day, and then deformed and displaced under the pressure of the quicksand on the second day.
Through continuous exploration, the construction team finally decided to adopt the construction method of pouring piles. According to the different environments of different tower foundations, increase the pile depth of the pile foundation. The average pile foundation is 8 to 30 meters, which provides sufficient support.
"In the selection of building materials, we recommend that the construction unit choose sulfate-resistant cement, which can effectively resist the corrosion of seawater and saline-alkali land and ensure the successful grid connection of wind power." Qu Cheng told our reporter.
With the maturity of equipment technology and the accumulation of development experience, China's offshore wind power development has gradually entered an accelerated period in the past two years.
At the end of 2021, a number of offshore wind power projects will be connected to the grid: On December 10, Huaneng Shandong Peninsula South No. 4 was connected to the grid at full capacity, becoming the first offshore wind power project in Shandong Province to achieve full capacity grid connection; on December 25, Jiangsu Dafeng Offshore Wind Power Project was officially connected to the grid at full capacity; on December 29, the last offshore wind turbine of the Dalian Zhuanghe Offshore Wind Farm Project was successfully connected to the grid...
"From a global perspective, China's offshore wind power is not very early, but it has shown very good prospects." Liu Jizhen said, "I believe that, as an important strategic support for China's green energy transformation and development, in the future, China's offshore wind power Wind power will continue to develop rapidly.”
Based on innovation——
The core competitiveness has obvious advantages
In the early development stage of China's offshore wind power generation, most of the onshore wind turbines are used for adaptive transformation and then put into the sea. Although they have certain reliability, the single-unit capacity is generally small; if foreign equipment is introduced, domestic enterprises do not master its core technology, operation and maintenance, Optimization is also controlled by people.
In this context, based on scientific and technological innovation, China has accelerated the research on core technologies. At present, China has the ability to independently develop and manufacture large-megawatt wind power units and key core components.
Recently, the 13 MW typhoon-resistant offshore wind turbine independently developed by China has been successfully rolled off in Fujian Three Gorges Offshore Wind Power Industrial Park. This is the wind turbine with the largest single-unit capacity and the largest impeller diameter in Asia that has been offline in China. rate reached 90%.
According to reports, the unit is independently developed by China Dongfang Electric Group Co., Ltd. and has completely independent intellectual property rights.
"According to the calculation of a 1 million kilowatt project, compared with 10 MW wind turbines, the selection of 13 MW wind turbines can reduce 23 seats, save about 500 million yuan in project cost, effectively reduce the cost of electricity, and improve the owner's investment income. rate." Zheng Dazhou, deputy general manager of Dongfang Electric Wind Power Co., Ltd.
It is worth mentioning that the successful launch of the 13 MW typhoon-resistant offshore wind turbine is inseparable from the incubation and cultivation of the Fujian Three Gorges Offshore Wind Power Industrial Park.
"Eight well-known domestic and foreign wind turbine manufacturers are competing here, not only to select the most suitable wind turbines for the development of my country's offshore wind power, but also to promote the localization and large-scale development of high-end offshore wind power equipment." Wang Wubin told reporters that through in-depth integration After a comprehensive analysis of the actual needs of China's offshore wind power development and the technical characteristics and advantages of each manufacturer, the industrial chain and the industrial park, through multiple rounds of coordination, clarify important indicators and parameters, and deeply participate in the whole process of large-capacity offshore wind turbine research and development.
"At the same time, we also support manufacturers in terms of technology and capital, and provide technical application feedback from the user side, so as to achieve common progress and mutual benefit with manufacturers, and then promote the upgrading of the entire industry."
On December 25, 2021, the Rudong offshore wind power flexible DC transmission project was fully put into operation, achieving a "zero" breakthrough in China's offshore wind power field.
Jiangsu Fangtian Power Technology Co., Ltd. undertakes the key task of commissioning and testing the core of its grid-connected offshore converter station.
"Flexible DC technology is a new type of DC transmission technology, which can effectively control the electric energy passing through it, just like connecting a fully controllable 'water pump' to the power system, which can precisely control the direction and flow of the 'water flow'." Fang Tian Yang Chun, project manager of the company's electrical technology center, said.
To safely and stably realize large-capacity, long-distance, and DC transmission of offshore wind power, the performance of high-voltage transmission cables at both ends of the sea and land is crucial.
"In the withstand voltage test, it is necessary to ensure that the cable is fully discharged. In the past, it was only possible to discharge naturally, and wait for the voltage to gradually drop." Yang Chun introduced that it has been estimated that the natural discharge of the flexible straightening project will take at least 10 hours, and the test period is positive. In summer, typhoons occur frequently, and the operation window period is extremely limited. If the traditional method is continued, the overall progress will be affected.
For this reason, Fangtian Company intervened in advance in the stage of cable design and manufacture, and jointly tackled key problems with cable manufacturers, and developed the world's first large-capacity DC equipment professional discharge system for land-sea DC cable handover test, which has overcome many worldwide problems. Shorten the discharge time to less than 50 minutes.
"On the whole, a series of key offshore wind power technologies such as large-capacity offshore wind turbines, ultra-long blades, and long-distance power transmission projects, which are locally developed and manufactured in China, have made important breakthroughs, and their technological innovation capabilities are in the world's first echelon, with core competitiveness advantages. Obviously," said Qin Haiyan, secretary general of the Wind Energy Professional Committee of the China Renewable Energy Society.
Opportunities arise -
Large-scale development prospects are promising
As a type of wind power development with large scale and high annual utilization hours, the advantages of offshore wind power have been shown in recent years, and development opportunities are emerging at an accelerated rate.
"During the '14th Five-Year Plan' period, the development and construction of offshore wind power will be further scaled." Wang Dapeng, deputy director of the New Energy and Renewable Energy Department of the National Energy Administration, said that with the release of relevant guidance documents, offshore wind power "has jumped in high quality. The theme of "development" will gradually become clear.
On March 21, the "14th Five-Year Plan for Modern Energy System" issued by the National Development and Reform Commission and the National Energy Administration proposed that to improve the level of clean and low-carbon energy development in the eastern region, it is necessary to actively promote the cluster development of offshore wind power in the southeastern coastal areas. Build offshore wind power bases in Guangdong, Fujian, Zhejiang, Jiangsu, Shandong, etc.
At the same time, many places have also anchored the "blue ocean" and successively issued plans to promote the large-scale development of offshore wind power.
Shandong Province actively develops the "main battlefield" of offshore wind power, focusing on the three major areas of Bozhong, North Peninsula and South Peninsula, and strives to build an offshore wind power base of 10 million kilowatts.
Accelerate the construction of affordable offshore wind power projects, promote pilot demonstrations of the integrated development of offshore wind power and marine ranching, explore the hierarchical and three-dimensional development of offshore wind power projects and other development and utilization methods, give full play to the comprehensive benefits of marine resource utilization, and promote the large-scale development of offshore wind power.
The "14th Five-Year Plan for Marine Economic Development in Guangdong Province" proposes that during the "14th Five-Year Plan" period, Guangdong Province will promote the large-scale development of offshore wind power projects, and strive to reach 18 million kilowatts of installed wind power capacity in the province by the end of 2025, and promote the offshore wind power industry. Cluster development, and accelerate the construction of Yangjiang and East Guangdong offshore wind power industry bases.
The "14th Five-Year Plan for Offshore Wind Power Project of Jiangsu Province" clearly states that there are 28 offshore wind power project sites in the "14th Five-Year Plan" plan, with a scale of 9.09 million kilowatts.
"We will rely on abundant marine resources to vigorously develop offshore wind power. By 2030, the total amount of renewable energy power will account for about 35% of the total electricity consumption of the whole society." Lu, Director of the New Energy Department of the Jiangsu Provincial Energy Bureau Introduce first.
Industry insiders generally believe that with the advent of large-scale development, floating offshore wind power will become a new track in the future.
Experts said that compared with the fixed foundation of traditional offshore wind power, floating offshore wind power has a wider scope of application.
Its floating foundation can move freely and is easy to dismantle, making it suitable for a wider range of sea areas.
In terms of economics, floating offshore wind power also has more potential for improvement in the future. For example, integrated structures can be used to simplify procedures and reduce offshore installation costs.
It is understood that China's floating offshore wind power is currently in the engineering demonstration stage, and the demonstration and verification projects have been installed and run for testing. China's Haizhuang engineering demonstration project will also be completed early this year.
In addition, the comprehensive development, utilization and integrated development of offshore wind power and marine ranching, offshore oil and gas, seawater desalination and other energy resources will also be an important development direction of offshore wind power in the future.
"Industry synergy and multi-energy complementarity will become the future development trend of offshore wind power. Scale, customization, intelligence, and large-scale are reliable ways to reduce costs and increase efficiency." Yuan Yingping, general manager of the Jiangsu Branch of the Three Gorges Group, suggested that offshore wind power should be established. The industrial chain covers the planning, design and site selection of offshore wind power, as well as professional services and software development for offshore wind power.
Lu Xian took the lead in saying that in the future, Jiangsu Province should do some demonstration and exploratory work in the coordinated development of the offshore wind power industry.
"At present, some of our offshore wind power companies have explored the mode of combining offshore photovoltaics, and further breakthroughs in technology are needed."