Jiangsu offshore wind project reaches milestone

Asia's first offshore wind power project to utilize flexible direct current (DC) transmission technology transmitted more than 10 billion kilowatt-hours of clean electricity to the grid in August, its operator China Three Gorges Corp (CTG) said.

According to CTG, the milestone demonstrates that the Jiangsu Rudong 800-megawatt offshore wind power project has successfully provided practical validation for the large-scale application of high-capacity, long-distance flexible DC transmission technology in China's offshore wind sector.

Located in the Huangshayang sea area off Rudong county, Nantong city, Jiangsu province, the facility is the world's largest-capacity and highest-voltage (±400 kilovolt) offshore wind flexible DC transmission project of its kind.

Since achieving full-capacity grid connection in 2021, the project has operated safely and stably for over 1,600 days, maintaining an impressive equipment availability rate of 99.5 percent, said CTG.

The 10 billion kWh of clean energy generated so far is sufficient to meet the annual electricity demands of approximately 4 million households. This output is equivalent to saving 3 million metric tons of standard coal and reducing carbon dioxide emissions by 7.4 million metric tons, significantly contributing to the nation's green transition, it said.

Operating in a harsh marine environment characterized by high humidity, high salinity, and frequent typhoons, the engineering team had to overcome a series of unprecedented challenges, including managing novel equipment, integrating complex systems, and handling difficult emergency responses.

The team successfully achieved technical breakthroughs in ensuring the stable operation of the ±400 kV flexible DC system, conducting long-distance submarine cable monitoring and maintenance, and regulating high-load working conditions. These efforts have ensured the safe, stable, and highly efficient operation of the far-offshore wind farm.

"Compared with traditional AC transmission methods, the project has reduced transmission line losses by approximately 1.2 percentage points, resulting in cumulative transmission cost savings of more than 735 million yuan ($102 million)," said Wang Xuefeng, deputy general manager of the Nantong company under CTG's Jiangsu branch.