China installs world‑record ±500 kV offshore DC converter, powering 60 billion kWh to the Greater Bay Area

On July 23, a 25‑tonne offshore converter station weighing about 25 000 t was successfully floated into position about 100 km off Yangjiang, Guangdong, in the South China Sea. The unit, nicknamed the “sea heart,” operates at ±500 kV and can transmit 2 000 MW, making it the world’s highest‑voltage and largest‑capacity offshore DC converter.

The station is linked to the San Shan Island offshore wind farm via an 88.8 km flexible‑current DC subsea cable and a 180 km overhead line on land. Together they will deliver roughly 60 billion kWh of clean electricity each year to the Guangdong‑Hong Kong‑Macau Greater Bay Area, offsetting about 5 million tonnes of CO₂. The project marks the first complete engineering solution for deep‑sea, high‑capacity wind power transmission and moves now into cable commissioning and land‑sea integration testing.

The achievement demonstrates China’s new “deep‑sea power” approach, using flexible DC technology to avoid the capacitive losses of traditional AC cables and to enable large‑scale offshore wind energy to be harvested over long distances.