China starts building first high-voltage AC/DC hybrid power grid project

NANJING -- China on Wednesday started the construction of its first high-voltage alternating current (AC) and direct current (DC) hybrid power grid project in Jiangsu province, marking another step toward a cleaner, safer and more efficient energy system.

The demonstration project will connect the two cities of Huai'an and Danyang, adding approximately 228 km of DC transmission lines to the existing power grid with two ±200 kV converter stations to be built at both ends, according to the State Grid Jiangsu Electric Power Co Ltd.

The project is expected to be operational after completion in 2026.

China's current main power grid is primarily composed of AC power grids. However, compared with AC transmission, DC transmission at the same voltage level can transmit larger amounts of power with lower energy losses.

Once operational, the project will significantly alleviate the pressure on north-to-south power transmission in Jiangsu and enhance grid flexibility, further expanding the application of hybrid grid technologies and helping develop a clean, low-carbon, safe and efficient energy system, according to the company.

China recently issued a plan to promote advanced technologies in key energy fields, including hybrid AC/DC power grids.