In the late autumn season on the Anggalai grassland, the autumn sun glitters like gold, the sky is high and the clouds are vast. Wind turbines dance with the wind, cattle and sheep graze leisurely—a scene of peace and harmony. The Group company's first single-unit largest-scale centralized wind power project—the Jilin Oilfield Angge 550,000-kilowatt wind power project—is located right here. The project was undertaken by Engineering Construction Company. Since it was connected to the grid and put into operation on September 29 this year, it has cumulatively generated 56.305 million kilowatt-hours of electricity, benefiting thousands of households.

In recent years, Engineering Construction Company has advanced steadily along the "green" path, successively undertaking two heavyweight projects—the Jilin Oilfield 150,000-kilowatt wind and solar power generation project and the Angge 550,000-kilowatt wind power project—helping Jilin Oilfield accelerate its green transformation and high-quality development.

Chasing the Wind: Meticulously Polishing Quality

The 150,000-kilowatt wind and solar power generation project is the Group company's first large-scale green electricity self-consumption project and also the first large-scale wind power project undertaken by Engineering Construction Company. Liu Zhaoxia, an electrical engineer at the Beijing Branch of Engineering Construction Company, recalled: "This project concentrated all modes of wind and solar power generation, and was extremely dispersed, including 12 centralized wind turbines, 6 distributed wind turbines, and more than 400 well-site photovoltaic power generation projects. An ordinary project only needs one booster station, but this project needed three."

During project construction, the Beijing Branch of Engineering Construction Company worked closely with wind turbine manufacturers. While meeting design requirements, they laid out turbine sites as reasonably as possible on abandoned well sites and beside Chagan Lake. "Black soil is precious—every inch is worth its weight in gold. What we considered most in design was how not to occupy cultivated land or affect the ecological environment," Liu Zhaoxia told the reporter.

In the first quarter of 2023, all 18 wind turbines of the project were put into operation. In the year it was commissioned, total wind power generation exceeded 180 million kilowatt-hours. Calculated by the natural year of project commissioning, the average effective utilization hours of the wind turbines reached 2,754, with power generation efficiency at an advanced domestic level.

The Angge 550,000-kilowatt wind power project includes 88 6.25-megawatt wind turbines, 100 kilometers of road construction, 155 kilometers of collector lines (including 805 towers), and one 220-kilovolt booster station, among other facilities. The Beijing Branch of Engineering Construction Company leveraged its EPC project management advantages, applying BIM throughout the process for three-dimensional visual disclosure, intuitively simulating the entire construction organization workflow as well as possible errors, omissions, clashes, and gaps, thereby achieving prior control of project quality. "The design team completed the design of a 220-kilovolt booster station for the first time, and carried out modular design of the booster station's static var generator (SVG), prefabricated cabins, and other equipment, so that the equipment can be installed quickly and conveniently upon arrival, facilitating later maintenance and expansion. At the same time, the booster station layout was optimized, accumulating important experience for the Group company's design of State Grid high-voltage substations," introduced Sun Tianlun, design manager of the Angge Joint Project Department (referred to as the Joint Project Department).

Battling the Wind: Safeguarding the Project's "Lifeline"

The Angge 550,000-kilowatt wind power project is located deep in the Anggalai grassland, with a construction area of 173 square kilometers. Because the terrain is low-lying, large mechanical equipment could only enter the site for construction after the ground froze solid in winter, greatly increasing construction and management difficulty. The Joint Project Department clarified the management interfaces and coordination processes of all parties, achieving standardized, procedural, and information-based on-site management; carried out tiered control of safety risks, identifying safety risks such as wind turbine lifting operations, turbine transportation, temporary electricity use at the construction site, and high-altitude work on high-voltage lines, preparing special plans, and refining control measures to ensure project safety and controlled risks.

Wind turbine foundation construction is the basis for ensuring progress. Completing the pouring of one wind turbine foundation requires 13 processes, including setting out, piling, dewatering, trenching, and laying cushion layers. To cope with minus 30 degrees Celsius severe cold and unexpected blizzards, the Joint Project Department adopted effective "local methods" such as dressing commercial concrete mixer trucks in "cotton coats," covering pile caps with "woolen quilts," setting up "warm sheds" and lighting "stoves" for secondary grouting curing. While ensuring the quality of winter concrete construction, this accumulated valuable experience for winter construction of wind power projects.

The colder it is, the more it is the golden construction period for the Angge 550,000-kilowatt wind power project. On November 6, 2023, a sudden blizzard struck the project construction site. Looking at the knee-deep snow, Liu Chao, general coordinator of the Joint Project Department, and Fan Changyong, manager of the construction department, were overjoyed—wind turbine installation requires large cranes, and the extreme cold weather caused the ground to form a frozen soil layer, so the cranes could finally travel on the frozen ground! Seizing this God-given opportunity, the participating employees busily prepared for the first lift of turbine No. 88.

The wind turbine is 118 meters tall, with a blade diameter of 195 meters and a weight of 595 tons, making construction extremely difficult. Shi Zengxian, leader of the 1,600-ton crane crew of the Mechanical Equipment Engineering Branch of the Seventh Construction Company, led the crane crew and worked closely with the lifting team led by Zhang Shiqiang, head of the lifting team. While meeting construction requirements such as no lifting when wind speed exceeds 6 meters per second, they worked day and night and successfully completed the first wind turbine lift of the Angge 550,000-kilowatt wind power project on November 13.

Since construction began in September 2023, the participating employees have anchored themselves to the goal of building a "safe, high-quality, efficient, clean, and exemplary" project. They overcame difficulties such as many work points, wide areas, long lines, great difficulty in winter construction management, and muddy roads in summer, fully advancing project construction and smoothly achieving the grid connection and commissioning goal on September 29, 2024. As of November 4, 86 of the 88 wind turbines had been put into use, and the remaining 2 will be installed at an appropriate time.

Riding the Wind: Creating a Speed Miracle

The Angge 550,000-kilowatt wind power project is not only the largest single-unit wind power project of the Group company and Jilin Province, but also the Group company's first large-scale wind power export project. Among construction projects of the same scale in the power industry, the project took only one year from commencement to commissioning, achieving a new breakthrough. Engineering Construction Company vigorously promoted integrated and shared transformation internally, facilitating integrated, shared management between internal design units and construction units, which became the key to accelerating and improving the project.

As early as the beginning of bidding for the Angge 550,000-kilowatt wind power project, the Beijing Branch proactively contacted the Seventh Construction Company of Engineering Construction Company to jointly analyze the bidding contract and determine the bid price, creating favorable conditions for forming the Joint Project Department. "The Beijing Branch is a design-oriented unit, and executing a general contracting project faces difficulties such as insufficient construction management personnel and lack of experience. Being able to jointly execute the project with our own sibling unit immediately gave us confidence," said Zhao Qiong, executive manager of the Joint Project Department.

Practice has proven that the establishment of the Joint Project Department effectively improved the practicality and feasibility of the design scheme and reduced uncertainty and risk factors during project implementation. Taking the outlet method of the wind turbine tower as an example, the conventional method is to have the outlet from embedded sleeves at the bottom of the foundation. On-site personnel from the Seventh Construction Company believed that this method would increase construction difficulty and costs, and that the schedule would be difficult to guarantee. The design team of the Beijing Branch immediately optimized the outlet method, changing it from an outlet at the bottom of the foundation to an outlet through the tower door. This not only reduced construction difficulty and lowered construction costs, but also ensured project progress.

The synchronous condenser is the core grid-connection equipment of the Angge 550,000-kilowatt wind power project, and also the first distributed synchronous condenser launched by the Group company. It weighs 180 tons and is equivalent to the height of a three-story building. The main unit has a huge number of supporting subsystems, equivalent to an independent power station. Procurement personnel overcame difficulties such as having no procurement experience to draw on, completed processes such as signing procurement contracts, issuing letters of guarantee, and paying advance payments in the shortest time, and coordinated with suppliers to complete in the shortest time the production scheduling of the synchronous condenser's main components—the stator and rotor—and the selection of suppliers for supporting subsystems. They also adopted measures such as directly stationing staff at factories to expedite delivery and directly managing suppliers of synchronous condenser subsystems to supervise and control specific progress. The commissioning of the synchronous condenser marks that the Beijing Branch has mastered core technologies such as the design, procurement, installation, and operation of synchronous condensers, filling a gap for the Group company in the procurement of supporting equipment for large booster stations.

The successful implementation of the two wind power projects of Jilin Oilfield helped Jilin Oilfield's green electricity achieve a transformation from a self-consumption model to a grid-connected electricity sales model, and made Engineering Construction Company the Group company's first enterprise to master the entire process of new energy grid-connected power generation and provide turnkey solutions and engineering construction services.