Construction of Zhejiang Section of Gansu-Zhejiang ±800 kV UHVDC Project Speeds Up

At 5 a.m. on September 5, there was still a slight coolness at the construction site of the transmission tower for the “Gansu-to-Zhejiang” ±800 kV UHVDC project in Fengqiao Town, Zhuji City, Zhejiang Province. Hong Zengtian, the on-site construction supervisor, had already led 20 workers to climb the transmission tower. “By avoiding the high noon temperature, we can ensure both progress and safety,” he said. This is his experience accumulated over the years: dividing the work into two periods every day—from 5 a.m. to 10 a.m. and from 3 p.m. to 7 p.m. Even so, the high temperature still makes high-altitude operations an “extreme challenge.”

“I have worked in this industry for more than 20 years, and I have gone through the hottest days and climbed the tallest towers,” Hong Zengtian said. His daily work is to lead the team in accurately assembling about 4,500 steel components of the transmission tower and more than 20,000 bolts at high altitudes for a single tower. When talking about the details of building transmission towers, he knows them like the back of his hand: “There are strict standards for the connection angle of each steel component and the tightening force of each bolt; even a little deviation is not allowed.”

The first transmission tower of the Gansu-Zhejiang ±800 kV UHVDC transmission line project within the territory of Shaoxing, Zhejiang Province is being erected

Photo by Zhou Zhihao

Zhejiang is a major economic province but a small energy province, with an energy self-sufficiency rate of less than 5%, yet its electricity consumption accounts for more than 6.7% of the national total. Externally transmitted electricity is an important means for Zhejiang to ensure power supply. Data shows that in the past decade, the length of 110 kV and above transmission lines and the transformer capacity in Zhejiang have increased by 55% and 83% respectively, and the scale of its power grid has ranked among the top in China.

The Gansu-Zhejiang ±800 kV UHVDC transmission line project is the fourth “West-to-East Power Transmission” project settled in Zhejiang. With a dynamic investment of about 35.3 billion yuan, the project has a total line length of 2,370 kilometers and a transmission capacity of 8 million kilowatts. The Zhejiang section of the project is 219.16 kilometers long, requiring the construction of 456 new transmission towers, covering 2 cities (Hangzhou and Shaoxing) and 5 districts (counties). At present, the construction within Zhejiang is advancing at full speed. After completion, it will add 8 million kilowatts of power transmission capacity to Zhejiang, support Zhejiang’s clean energy transition, and help promote the green and low-carbon development of the economy and society. (Written by Zhang Qibin)