Transmission towers dominate the skyline in Qingyang in Gansu province. [Photo provided to CHINA DAILY]

A landmark ultra-high-voltage direct current transmission line has moved 28.8 billion kilowatt-hours of electricity from China's resource-rich northwest to its eastern economic hubs during its first full year of operation, marking a major milestone in the country's cross-regional energy rewrite.

Armed with a capacity of 8 million kilowatts, the Gansu-to-Shandong line is designed to ultimately transmit over 36 billion kWh annually — equivalent to roughly two-fifths of the total power output of the Three Gorges Dam.

Since operations began on May 8 last year, the transmission corridor has supplied electricity to the municipalities of Beijing, Shanghai and Tianjin, and Jiangsu and Zhejiang provinces, helping ease power demand pressure in eastern China while expanding consumption channels for Gansu's renewable energy.

The power transmitted in that line was enough to power about 8 million three-person households for one year, according to State Grid Gansu Electric Power Co.

More than 40 percent of the energy transmitted over the past year was sourced from wind and solar farms, effectively saving 3.54 million metric tons of standard coal, the company said.

During a key supply crunch in November 2025, the line successfully routed 290 million kWh of green electricity to Shanghai within a 10-day window, ensuring 100 percent renewable energy coverage for the China International Import Expo.

As a key corridor under China's West-to-East Power Transmission strategy, the Gansu-to-Shandong±800 kilovolt ultra-high-voltage direct current transmission project is the country's first large-scale transmission line integrating wind, solar and thermal storage resources.

It delivers electricity from Qingyang in Gansu to Dongping in Shandong, accelerating the growth of Gansu's new energy industries and providing a stable, large-scale electricity supply to eastern China while advancing the country's "dual carbon" goals.

In Qingyang and Baiyin in Gansu, large-scale wind, solar and storage projects have expanded rapidly, while manufacturers of wind turbines, storage systems and hydrogen equipment are scaling production.

"Gansu has abundant renewable energy projects and strong market demand," said Mu Xinghui, a manager at Yishite Digital Equipment Manufacturing in Qingyang. "Producing here reduces transportation costs and allows companies to respond quickly to customer demand."

Along the Bohai Bay coast in Shandong, ports including Weifang, Binzhou and Dongying are using electricity transmitted from Gansu to support their operations.

"With electricity delivered from Gansu, we have greater confidence in the energy supply for port operations," said Han Guopeng, head of safety and operations maintenance at Shandong Port Energy Development Weifang. "In particular, green electricity has further strengthened Weifang Port's confidence in building a zero-carbon port."

Gansu's installed new energy capacity exceeds 80 percent of its total installed power capacity, while the output value of its new energy industry has surpassed 100 billion yuan ($14.8 billion), as the province continues to transform its rich renewable resources into a driver of low-carbon economic growth.

The project was the first UHV DC transmission line commissioned during the 14th Five-Year Plan period (2021-25), according to Zhang Jun, director of main grid planning at the company. It is also the country's first UHV DC project to achieve full capacity operation in a single commissioning.

"Facing a UHV transmission system with a high proportion of new energy and bundled transmission of wind, solar, thermal power and storage, scientific coordination is key," said Liu Kequan, director of the dispatching division at the State Grid Gansu Electric Power Dispatching Center.

"We have adopted a coordinated operating model featuring thermal power for peak regulation, renewable energy as the main supply source, and energy storage for support. By optimizing operating strategies in real time, we have achieved both a stable thermal power supply and maximum renewable energy utilization."