First Tower of China's Zhejiang 29.3 Billion Yuan UHV AC Ring Network Project Completes Erection

en.Wedoany.com Reported - On November 10, the first tower of the Zhejiang UHV AC Ring Network Project was erected in Shangyu District, Shaoxing City, marking the project's full entry into the tower erection phase. The project involves a total investment of 29.3 billion yuan, with the line route passing through Jiaxing, Hangzhou, Shaoxing, Ningbo, Taizhou, Wenzhou and Lishui. It will build 508 kilometers of new double-circuit lines, with more than 2,000 towers planned along the entire route. Following the completion of this first tower erection, subsequent line construction will proceed with tower foundations, erection and crossing section operations across various contract sections.

The Zhejiang UHV AC Ring Network Project is a key project in China's 15th Five-Year Plan for power development. Built by State Grid, it starts in Jiaxing and ends in Lishui, with three new 1,000 kV UHV substations to be built along the route in Jiaxing, Ningshao and Wenzhou, and the Liandu UHV substation to be expanded. The project will add 18 million kVA of substation capacity and build 508 kilometers of new double-circuit transmission lines. Once completed, it will connect Zhejiang's existing UHV AC transmission network into a ring, forming a "one ring, four direct current" UHV grid structure.

Line construction faces multiple challenges, including mountainous terrain, crossings over existing transmission lines and complex construction environments. The contract section that took the lead in tower erection includes 6 towers, some of which require construction work crossing over 500 kV transmission lines currently under renovation. The construction unit arranged operations during power grid outage windows, adjusted construction procedures, and deployed multiple sets of mechanized equipment tailored to the mountainous terrain, organizing simultaneous erection of multiple towers to control cross-operation risks and manage the construction schedule of critical lines.

In addition to ground-level transmission line construction, the project also involves crossing beneath the Qiantang River, where a gas-insulated transmission line (GIL) culvert solution will be adopted to build approximately 3,736 meters of power tunnel beneath the riverbed, reducing the impact on the Qiantang River waters and coastal environment. The project will also add multiple UHV substation facilities and adopt equipment such as 1,000 kV high-impedance transformers, involving multiple construction elements including transmission lines, substations and cross-river transmission corridors.

According to the previously announced construction schedule, the Zhejiang UHV AC Ring Network Project is planned to be completed and put into operation in November 2029. Upon operation, the project will connect the power grids of northern, central and southern Zhejiang, forming a provincial UHV AC transmission ring network and providing main grid support for the integration of coastal nuclear power, offshore wind power and pumped-storage hydropower in the western mountainous areas, as well as for cross-regional power transmission.