The golden waterway of the Yangtze River has been transformed into the world's largest clean energy corridor. One drop of water can generate 6 times of electricity.
The mighty Yangtze River gathers great rivers and runs through the Yangtze Gorge, and contains abundant water energy, shipping, fresh water and other resources.
Six large hydropower stations, Wudongde, Baihetan, Xiluodu, Xiangjiaba, Three Gorges and Gezhouba, are arranged from top to bottom along the main stream of the Yangtze River, forming the world's largest clean energy corridor: spanning more than 1,800 kilometers, with a water level drop of more than 900 meters. 110 hydro-generator units continue to operate, and the vast river water brings green electricity.
Not long ago, the industrial Internet platform was deployed in six cascade hydropower stations, marking the basic completion of the "industrial brain" of the world's largest clean energy corridor. The operational efficiency, safety and reliability of hydropower stations have been greatly improved.
The cumulative power generation of the six cascade hydropower stations exceeded 3.5 trillion kilowatt-hours, which is equivalent to saving more than 1 billion tons of standard coal and reducing carbon dioxide emissions by more than 2.8 billion tons. At the same time, the coordinated cooperation of cascade reservoirs will comprehensively release benefits such as smooth shipping, water resources security, and ecological protection.
Figure ①: Wudongde Hydropower Station. Photo courtesy of China Three Gorges Corporation
Figure ②: Baihetan Hydropower Station. Photo by reporter Chen Xinbo
Data: 71.695 million kilowatts total installed capacity
"One drop of water generates 6 times of electricity", six reservoirs joint debugging makes the "green engine" more powerful
Baihetan Hydropower Station is located in a deep canyon. The concrete double-curved arch dam with a maximum height of 289 meters captures the rushing river water. The water flowing down from a height of more than 200 meters drives the wheel of the hydroelectric generator unit to rotate. Each rotation of the unit can generate about 150 kilowatt hours of electricity.
The 16 1,000,000-kilowatt hydroelectric generating units of Baihetan Hydropower Station are operating at full capacity. Wang Bin, deputy director of the operation department of Yangtze Power Baihetan Power Plant, said: "Operation personnel are on duty 24 hours a day, and sensors collect data in real time. Once the operation indicators are abnormal, the system will automatically give an early warning."
"The generator set is like a top rotating by water power, converting kinetic energy into electrical energy." Kang Yonglin, former deputy director of the Baihetan Engineering Construction Department of China Three Gorges Corporation, said that at a speed of 111 revolutions per minute, the generator standing on it The coin did not move at all, and the swing of each bearing during operation was less than 0.1 mm... "Key technologies such as the overall layout of the unit, electromagnetic design, and major component manufacturing have successively achieved important innovative results, witnessing China Hydropower's leadership in equipment manufacturing, design and installation, etc." status."
In December 2022, all units of the Baihetan Hydropower Station will be put into operation and generate electricity. Looking back from Baihetan, this clean energy corridor has witnessed breakthroughs in my country's hydropower technology.
Completed in the 1980s, Gezhouba has a maximum capacity of 170,000 kilowatts per unit of hydroelectric generator. As the world's largest water conservancy project, the Three Gorges Hydropower Station has mastered the design and manufacturing technology of the 700,000-kilowatt unit. Subsequently, the Xiluodu, Xiangjiaba and Wudongde hydropower stations were constructed, and the single unit capacity of the hydroelectric generating units exceeded 770,000, 800,000 and 850,000 kilowatts respectively.
Upgrading is not a simple addition, the difficulty coefficient of R&D technology increases exponentially every time. The single-machine capacity has moved towards the million-kilowatt level, which is inseparable from the application of a series of new processes and new materials, and has achieved the upgrade of the entire industry chain such as hydraulic design, generator ventilation, and overall unit design. "Million-kilowatt units have greater water head impact, faster rotation speed, and higher pressure. China Three Gorges Corporation led large steel companies to develop 800 MPa high-strength volute steel plates, getting rid of the long-term dependence on imports." Li Haijun, deputy director of the group's electromechanical technology center, gave an example.
The total installed capacity of the six cascade hydropower stations reaches 71.695 million kilowatts, which is equivalent to the installed capacity of three Three Gorges Hydropower Stations, continuously enhancing the confidence in energy supply, and five of them have become the backbone power stations of the "West-East Power Transmission".
"The Yangtze River water passes through 6 hydropower stations in sequence, which is equivalent to 1 drop of water generating 6 times of electricity." Kang Yonglin calculated a detailed account: 1 cubic meter of water passing through the Three Gorges Hydropower Station can produce 0.25 kilowatt hours of green electricity; the joint regulation of the six reservoirs achieves a power generation multiplier. Effect, the power generation can reach 2 kilowatt hours, and the efficiency is increased to 8 times.
"The operation and dispatch of giant power station groups in the basin involves multiple links of 'water, machinery and electricity'. It is huge in scale, changeable in time and space, cross-regional and cross-network, and has a complex structure. Cascade hydropower stations bear both peak load and base load, which is critical to the long-term safety of hydropower. Stable operation puts forward higher requirements," said Tang Zhengyang, deputy director of the Yangtze Electric Power Science and Technology Research Center. The industrial Internet platform deeply empowers all business scenarios such as intelligent operation and maintenance, intelligent maintenance, intelligent dispatching, and intelligent decision-making, comprehensively improves the level of intelligent operation and maintenance of equipment, and assists the digital construction of hydropower stations.
Release the "golden benefits of golden waterways" to help the Yangtze River cargo volume maintain its leading position
Three Gorges Dam, double-line five-level ship lock is located on the left bank. In 2023, the ship lock will operate safely for more than 11,000 times, and more than 42,000 ships will pass through it - the gable gate of about 900 tons will be opened tens of thousands of times, and the 1,000-ton giant ship will climb a water level drop of 113 meters. How to operate it safely and efficiently?
"The Three Gorges Ship Lock is the largest inland river ship lock in the world, with the most consecutive stages, the highest water head, and the most complex operating conditions. During operation, we have established mechanisms to ensure smooth shipping." Deputy Director of the Hub Management Department of the Three Gorges Group River Basin Hub Operation Management Center Yang Hua said that in order to ensure the safety and reliability of various construction equipment, the Three Gorges Ship Lock will regularly implement planned shutdowns for maintenance. On April 5, the 2024 planned outage and maintenance of the Three Gorges North Line Ship Lock came to a successful conclusion. This is the longest construction period, heaviest task, and most difficult process connection and coordination since the planned outage and maintenance began in 2012. 16 units and more than 800 people participated. Within 45 days, they mainly completed the upgrade of the Three Gorges ship lock industrial control system, the maintenance of 12 herringbone doors and 12 anti-arc doors, and the replacement of 9 sets of oil cylinders, which further improved the safety and reliability of ship lock operations. .
When crossing the Three Gorges, you can not only "climb the stairs" but also "take the elevator". On the right side of the lock is the Three Gorges Ship Lift. Yang Hua introduced that the ship-carrying compartment with a height of 10 meters and a water depth of 3.5 meters can accommodate a 3,000-ton ship and can be raised to a height of nearly 40 stories in just 10 minutes. From January to April this year, the freight volume passing through the Three Gorges Ship Lock exceeded 41.4 million tons, the ship lift safely operated 1,685 times, and the freight volume passing through the ship exceeded 1.96 million tons, a year-on-year increase of 127.73%.
The Xiangjiaba Ship Lift is the second giant ship lift built in my country after the Three Gorges Ship Lift. The annual cargo capacity in 2023 increased by 15.51% compared with the previous year; the Gezhouba Ship Lock has been open to navigation for more than 40 years, and the average number of daily lock operations has been The number of gates has been increased from 8 to 49. According to the relevant person in charge of the Three Gorges Group Basin Hub Operation and Management Center, the Three Gorges, Xiangjiaba and Gezhouba water conservancy hubs have promoted the development of Yangtze River shipping and economic development along the river, helping the Yangtze River freight volume to continue to rank first in the world's inland rivers.
Six cascade hydropower stations have formed a 768-kilometer deep water channel in the reservoir area, and the navigation conditions of the Yangtze River have been steadily improved.
Sections of rapids and rapids turned into water thoroughfares. After the completion of the Three Gorges Project, the maintenance water depth of the waterway from Chongqing to Yichang increased from 2.9 meters to 3.5 to 4.5 meters, the tonnage of ships increased from 1,000 tons to 5,000 tons, and 109 beach hazards and 34 one-way controls were placed between the dam site and Chongqing. The river section and the 12 navigation sections that need to pass through the shoals have been eliminated, and "night navigation on the Sichuan River since ancient times" has become history.
Each port grows from small to large to strong. There are multiple deep-water terminals with a capacity of over 5,000 tons on the Yangtze River waterway in Chongqing. Ports in the Three Gorges reservoir areas such as Yichang in Hubei, Fuling in Chongqing and Wanzhou are booming. The advantages of Yangtze River water transportation such as low energy consumption, large transport capacity and low cost have been fully utilized, further releasing the "golden benefits of golden waterways".
Form a strategic freshwater resource bank to provide support for water supply, water replenishment, and ecological regulation
The Yangtze River Basin is a strategic water source for my country's water resources allocation, with a multi-year average water resource volume of 995.9 billion cubic meters, accounting for approximately 36% of the country's total. Among them, this clean energy corridor forms a cascade reservoir group with a total storage capacity of 91.9 billion cubic meters and a strategic freshwater resource bank.
The water supply and replenishment effect is significant. Li Peng, deputy chief engineer of Yangtze Power's Three Gorges Elevator Diversion System, said: "We reasonably coordinate the regulation and storage plan and energy supply requirements to ensure the comprehensive benefits of water supply, power generation, shipping, and ecology."
Ecological dispatch continues to be carried out. Fish resources are an important indicator of river health. Reservoirs increase discharge flow in an orderly manner and create a slow rise in water levels in river sections, which can create conditions for natural fish reproduction. 2023 is the second year that Wudongde, Baihetan, Xiluodu, Xiangjiaba, and Three Gorges reservoirs have all been included in the scope of ecological dispatch. Relevant units have coordinated and organized the implementation of layered water intake and temperature regulation through stacked beam gates and "base load power generation" to promote production. The world's largest clean energy corridor has become an ecological protection corridor through 12 ecological dispatch tests in three categories, including the reproduction of fish with clinging eggs and the promotion of reproduction of fish with drifting eggs.
The scope of ecological dispatch continues to expand. According to the relevant person in charge of the Yangtze River Water Conservancy Commission, the current dispatching objects have expanded from promoting fish reproduction to regulating water temperature in stratified water intake, preventing and controlling algae blooms, draining sand and siltation in the reservoir area, and inhibiting the excessive reproduction of submerged plants. Reservoir dispatching Expanding from the Three Gorges Reservoir to cascade reservoirs in the Jinsha River, Yalong River, Han River and other river basins, we will vigorously promote the protection and restoration of water ecology in the Yangtze River Basin.
The relevant person in charge of the Three Gorges Group said that the comprehensive benefits of the world's largest clean energy corridor will provide strong support for flood control safety, shipping safety, energy security and ecological security in the Yangtze River Basin at a higher level, in a wider field, and at a larger scale, and will continue to Promote high-quality development of the Yangtze River Economic Belt.
Published in "People's Daily" Page 2, May 15, 2024
