Super power station, casting the "new business card" of China's hydropower
In early spring, at the junction of Sichuan and Yunnan provinces, in the narrow and deep valley of the Jinsha River, an extra-high arch dam stands majestically. This is the second largest hydropower station in the world - Baihetan Hydropower Station.
As of 12:59 on February 17, the Baihetan Hydropower Station has safely produced 20 billion kWh of green electricity, equivalent to a reduction of 6.24 million tons of standard coal consumption.
Today, going up the Yangtze River, among the six giant cascade hydropower stations, including Gezhouba, Three Gorges, Xiangjiaba, Xiluodu, Baihetan, and Wudongde, constructed and operated by China Three Gorges Corporation (hereinafter referred to as “Three Gorges Group”), there are 5 are among the top 12 hydropower stations in the world.
This means that the Yangtze River Basin has become the world's largest clean energy corridor, providing a steady stream of green power for high-quality economic and social development.
How was the world's largest clean energy corridor built?
What are the benefits of these super hydropower plants?
Recently, our reporter conducted an interview.
Six cascade power stations "connected in a string"
Walking in the power plant on the left bank of the Three Gorges, at the end of the line of sight, a bright five-star red flag hangs on the high wall.
With the flashing lights, 14 700,000-kilowatt hydro-generator units are running to generate electricity.
With 32 giant generating units, the Three Gorges Hydropower Station can generate more than 100 billion kWh of electricity annually. It is the backbone of China's "West-to-East Power Transmission" and "North-South Mutual Supply", as well as the commanding heights of the world's hydropower.
But it is not the starting point for the construction of the world's largest clean energy corridor.
In December 1988, at the mouth of Xiling Gorge in the middle reaches of the Yangtze River, the Gezhouba Hydropower Station, which was built on the basis of the "first dam of the Yangtze River" in the early 1970s, was fully completed and put into operation, officially opening the prelude to the large-scale utilization of clean energy in the Yangtze River, and contributing to the development of the Three Gorges. Engineering construction has accumulated valuable experience.
"Establish the stone wall of the Xijiang River, cut off the clouds and rain in Wushan, and leave the Pinghu in the high gorge." Six years later, the construction of the world's largest hydropower station, the Three Gorges Hydropower Station, officially started.
Due to the insufficient domestic manufacturing level at that time, when the Three Gorges Left Bank Power Plant units were tendered, China introduced 14 700,000-kilowatt giant units for the first time through international bidding.
Surprisingly, foreign technology is not fully adapted to the reality of the Three Gorges Power Station, and the Three Gorges builders immediately started research.
Hard work pays off. After nearly a month of argumentation and discussion, the Three Gorges builders finally found a solution.
"At that time, I was very anxious. This experience made us realize that we must have our own turbine manufacturing technology." said Li Zhixiang, former deputy director of the Three Gorges Power Plant.
The distance from the left bank power station of the Three Gorges to the right bank power station is only more than 1 km, but the development level of hydro-generator units has spanned the gap of 30 years.
Li Zhixiang told reporters that among the 12 units of the Three Gorges Right Bank Power Station, 8 are localized units with higher independent intellectual property rights, and the 6 units of the underground power station have a higher degree of localization.
In July 2012, the Three Gorges Power Station with a total installed capacity of 22.5 million kilowatts was completed, successfully raising the utilization level of hydropower resources in the Yangtze River to the level of 10 million kilowatts for the first time.
China Hydropower is located in the southwest, and Southwest Hydropower is located in Jinsha.
With the realization of the initial goals of water storage, navigation and power generation in the construction of the Three Gorges Project, the Three Gorges Group began to march into the Jinsha River.
In June 2014, the Xiluodu Hydropower Station with a total installed capacity of 13.86 million kilowatts was put into full operation to generate electricity; in July of the same year, the Xiangjiaba Hydropower Station with a designed installed capacity of 8 units and a total installed capacity of 6.4 million kilowatts was fully completed and put into operation; in June 2021, the world's seventh largest hydropower station , The fourth largest hydropower station in China, Wudongde Hydropower Station, was fully put into operation for power generation.
Today, Baihetan Hydropower Station, which is the most difficult to construct among the four major hydropower stations on the Jinsha River, has also entered the final sprint stage.
On January 18, the hoisting of the rotor of the last million-kilowatt hydro-generator set of the Baihetan Hydropower Station was completed. It is expected that the Baihetan Hydropower Station will be fully put into operation before July this year.
"From the Jinsha River to the Yangtze River, the six cascade hydropower stations are 'connected in a string' and are well-deserved national treasures. The high-quality and low-cost clean energy they output will generate huge ecological, social, economic and other comprehensive benefits. Hydropower's 'new business card'." said Wang Hao, academician of the Chinese Academy of Engineering.
Data show that after the Baihetan Hydropower Station is fully put into operation, the total installed capacity of the six hydropower stations along the main stream of the Yangtze River will reach 71.695 million kilowatts, with an average annual power generation of about 300 billion kilowatt-hours, which is equivalent to reducing carbon dioxide emissions by 249.6 million tons per year.
"Cascade hydropower stations have a large amount of power generation and strong peak shaving capacity, and play an important role in optimizing the energy structure, maintaining the stable operation of the power grid, and promoting energy conservation and emission reduction." Li Peng, director of the Three Gorges Elevated Water Resources Department of the Three Gorges Group Yangtze Power, told reporters. , the next step will actively promote the optimization and upgrading of existing hydropower stations, and strive to contribute more clean energy security to the country.
Independent innovation casts great power
In fact, the rise of the world's largest clean energy corridor is also the road of independent innovation for major hydropower equipment from "Made in China" to "Created in China".
The Wudongde Dam with a height of 270 meters, with a total pouring volume of 2.7 million cubic meters, is the thinnest 300-meter ultra-high arch dam in the world.
"The difficulty of its construction lies first in the temperature control in the pouring of mass concrete." Yang Zongli, director of the Engineering Construction Department of Wudongde, said that no dams and no cracks used to be a "nightmare" haunting the world's water conservancy people. "Cement hydration in concrete" The reaction generates heat, and if effective temperature control measures are not taken, cracks will inevitably develop.”
If you want to solve the problem, the selection of materials is the key.
In order to solve the world-class problem of easy cracking of cement, the builders of Wudongde conducted multiple rounds of screening of concrete raw materials, and finally created a precedent in the history of dam construction in the world - the whole dam was poured with low-heat cement concrete.
Different from ordinary cement or medium-heat cement, low-heat cement has low calorific value, and has the characteristics of "slow temperature rise, small temperature rise, and high comprehensive crack resistance", which helps to prevent dam cracks.
"Low-heat cement is also known as the 'fever-reducing drug' for dams. As early as during the construction of the Three Gorges Project, we started the research on low-heat cement. Through continuous testing and improvement, it was the first time to achieve full-dam application on the Wudongde Dam. A 'seamless dam' was built on top of it," said Yang Zongli.
While pursuing material innovation, the world's largest clean energy corridor is also making strides in intelligent construction.
During the construction of Xiluodu Hydropower Station, technicians conducted research and application of key technologies for intelligent construction of 300-meter-level extra-high arch dams, and developed an information platform (iDam) for the construction and operation of intelligent arch dams.
This shared, collaborative and interactive business platform manages 3,496 safety monitoring instruments, 4,723 concrete thermometers and 24,000 meters of temperature-measuring optical fibers, effectively supporting on-site production management.
"Thanks to the information platform, Xiluodu has a smart 'brain', and the technicians who build and manage the dam can know its 'headache and brain fever' at any time, and make dynamic adjustments in time to keep the dam in a 'healthy state'." Fan Qixiang, a professor-level senior engineer and former deputy general manager of the Three Gorges Group, who participated in the construction of the Xiluodu Hydropower Station, introduced.
Not only that, relying on intelligent construction, the super hydropower station continuously optimizes and improves the construction process, and continuously improves the construction quality and efficiency.
Take the intelligent water control system as an example.
In the past hydropower construction projects, artificial cooling was often used to cool concrete, and the temperature control accuracy was not satisfactory.
Nowadays, the intelligent water supply system can intelligently adjust the water flow, temperature and time through temperature sensing instruments, and conduct online personalized temperature control.
"Just click on the phone, all the parameters are clear at a glance, and the engineer only needs to check the system on time, which is very convenient." said Wang Wei, director of the technical management department of Baihetan.
"A nine-story platform starts from the accumulation of soil." Relying on participating in the development of the 700,000-kilowatt unit of the Three Gorges Project, and by taking the road of "introduction, digestion, absorption and re-innovation", in recent years, Chinese equipment manufacturing enterprises have gradually mastered the overall design and development of large-scale hydraulic turbine units. The key core technology of manufacturing.
For example, the difficulty of developing a generating unit with a single capacity of one million kilowatts in the Baihetan Hydropower Station can be described as the "Mount Everest" of hydropower in the world.
"The rotating parts of the unit are composed of tens of thousands of parts and weigh 2,600 tons. A single unit can generate nearly 17,000 kilowatt-hours of electricity per minute." said Wang Xiaojun, the on-site general representative of the Baihetan Project Department of Dongfang Electric Group.
"From the 700,000 kilowatts of the Three Gorges to the 800,000 kilowatts of Xiangjiaba, from the 850,000 kilowatts of Wudongde to the 1 million kilowatts of Baihetan, these super hydropower stations have witnessed the upgrading of China's hydropower units. ." Yang Zongli proudly said that at present, China's "stuck neck" technology in the field of hydropower no longer exists.
"From the beginning of the Three Gorges to the end of Baihetan, we have realized the independent design, independent manufacturing, independent intellectual property rights and national production of important raw materials for hydropower equipment throughout the process, and realized the process of 'following', 'running side by side', and finally 'leading' A leap forward." said Lei Mingshan, chairman of the Three Gorges Group.
The corridor is shaped to benefit the people of one party
The world's largest clean energy corridor, the most critical function is to transport green energy to the eastern region as an important project of "West-to-East Power Transmission".
But the super hydropower station is the most important tool of the country, and its social benefits do not stop there.
The social benefits of cascade hydropower stations lie first in flood control.
"Currently, the world's largest clean energy corridor has a total flood control storage capacity of 39.2 billion cubic meters, effectively improving the flood control standards of important river sections." The flood control standard of the Sichuan-Jiangjiang reaches has been raised from about once in 10 years to no less than once in 50 years.
In recent years, in the face of challenges such as the large number of newly-built reservoirs in the upper reaches of the Yangtze River and the sudden turn of droughts and floods at the end of the flood season, relying on the self-developed water resources management decision support system, the Three Gorges Group has scientifically carried out the joint dispatch of the six reservoirs, and coordinated the ebb and flow of cascade hydropower stations. flood control, etc.
In September 2021, affected by heavy rainfall, the inflow of water from the Mintuo River, Jialing River and the Three Gorges in the upper reaches of the Yangtze River increased, resulting in the "Yangtze River No. 1 Flood in 2021".
"With the help of the decision support system, we accurately predicted a week in advance and formulated a flood containment plan." Tang Zhengyang, deputy director of the Yangtze River Power Water Resources Research Center of the Three Gorges Group, introduced that during the flood process, four cascade hydropower stations including Wudongde blocked the flood. 4.243 billion cubic meters, the Three Gorges Hydropower Station blocked 7.46 billion cubic meters of floods, and the maximum peak shaving rate exceeded 50%.
"The hydropower cluster will definitely increase the overall power generation, and we are currently working on joint research." He Wei, Secretary of the Party Committee of the Baihetan Engineering and Construction Department, said, "The rainfall is abundant, and the water that cannot hold it is called a flood, but with so many cascade power stations, flooding It becomes a valuable power generation resource.”
"The Jinjiang River has been impassable for boats since ancient times, and the waters are so high that the sky is so high that one can look down upon it." For thousands of years, traffic congestion has been one of the chronic diseases that have led to the stagnation of economic development along the Jinsha River.
After the completion of Baihetan Hydropower Station, the total length of the four cascade reservoirs in the lower reaches of the Jinsha River is about 612 kilometers. After the implementation of the dam-turning and transfer facilities, the “Panzhihua-Shuifu” can be realized through the combined water and land transportation. The connection of water transportation channels creates conditions for the construction of comprehensive three-dimensional transportation corridors.
At the same time, during the dry season, the world's largest clean energy corridor has accumulatively replenished more than 34 billion cubic meters of water to the downstream, increasing the shipping depth of the middle and lower reaches by 0.9 meters, improving the navigation conditions of the "golden waterway" of the mainstream of the Yangtze River, and effectively ensuring the downstream spring ploughing and production. domestic water needs.
As a booster to promote the construction of the Yangtze River Economic Belt and the coordinated development of the regional economy, the world's largest clean energy corridor has the advantages of large investment, strong driving force and huge comprehensive benefits.
For example, the Baihetan Hydropower Station has not only improved the transportation, communication and other infrastructure conditions in the surrounding areas, but also created about 80,000 jobs for the local area during the peak construction period of the hydropower station.
After all the units are put into operation, it can increase the local financial revenue by 2.9 billion yuan every year, and become an engine for promoting local economic and social development.
People who used to live near the water also moved into new homes and lived a good life because of the construction of Baihe Beach.
Cut off the tips of the corn leaves, splice several pieces of broken leaves, hold them in your hands, scoop up a tablespoon of the fermented rice milk, and quickly put them into the steamer... Every afternoon, She, who lives in the Qili resettlement area of Qiaojia County, Yunnan Province, Gang Yan will be busy in the storefront he rents.
"On our side, making corn cakes is a specialty. Moving to a new home, this craft can't be broken." Shegang Yan said cheerfully.
"Actually, I had the idea of opening a shop and doing business very early, but I didn't have the conditions in my hometown. Moving to the resettlement area gave me a chance to realize my dream." She Gangyan said that she makes Baba every afternoon and sells it wholesale the next morning. "Now that life is more stable and income is more, it's really a good time to catch up."
The world's largest clean energy corridor also bears the major responsibility of conserving and restoring the ecological environment of the Yangtze River Basin.
In order to effectively protect the water environment, the Three Gorges Corporation has built a pollution prevention and control system and a sewage treatment system in the reservoir area, and established a corresponding water ecological monitoring system in the lower reaches of the Jinsha River for real-time observation and feedback.
In 2021, a total of 8 ecological dispatches will be carried out. During the period, the total number of fish spawning in the lower reaches of Gezhouba exceeds 12.4 billion, of which the spawning scale of the four major fish exceeds 8.4 billion, which is the highest in history.
"We will follow the relevant requirements of the "Yangtze River Protection Law" to undertake the new mission and new task of playing a key role in the joint protection of the large-scale protection, so that the clear water of the river will last for future generations, and the mother river will remain alive forever." Lei Mingshan Say.
Liu Leyi