On July 27 at 10:16 a.m., with the final conductor segment of the Yanwei 1000-kilovolt Ultra-High Voltage project pulled into place, the Yanwei UHV ring network, located in the eastern part of the Jiaodong Peninsula, was officially closed. This milestone marks the full completion of China's first provincial-level UHV dual ring network.

The Yanwei UHV project is a key component of the nation's first provincial "dual ring network" for ultra-high voltage. Stretching a total of 1,197 kilometers, the line passes through five cities: Yantai, Qingdao, Rizhao, Weifang, and Linyi. It serves as a vital channel for transmitting clean energy from the Jiaodong Peninsula.

"After completion, the eastern peninsula ring network will combine with the existing central-western ring network to form a 'sun-shaped' UHV AC dual ring network, making the grid more stable and green power transmission more flexible," said Cheng Jian, head of the UHV Management Division at State Grid Shandong Electric Power's Construction Department.

In recent years, driven by the rapid development of clean energy sources such as nuclear power and offshore wind power on the Jiaodong Peninsula, the region is rapidly transitioning from a "power receiver" to a "power sender." It is expected that by the end of the "15th Five-Year Plan" period, the surplus power that needs to be exported from the Yantai-Weihai area will exceed 30 million kilowatts.

To ensure clean energy can be delivered stably and reliably, the Yanwei UHV project overcame the complex conditions of simultaneous construction in mountainous and marine areas. It innovatively adopted five major technology systems: "fully mechanized construction in composite geology, intelligent concrete curing under low winter temperatures, full-dimension durable anti-corrosion for marine environments, integrated line disaster prevention plus intelligent inspection, and construction roads combined with inspection walkways." These innovations filled multiple gaps in China's UHV marine construction sector and provided valuable experience for similar projects in the future.

It is understood that the effective construction period for the Yanwei UHV project was 12 months, setting a new record for the fastest construction time among UHV AC projects of the same scale nationwide. The project is expected to be officially put into operation in October this year.