BEIJING, Oct. 8 -- A 1,000 kilovolt (kV) gas-insulated transmission line (GIL) utility tunnel project, a signature project of State Grid, has been put into service in east China.

It consolidated the company's leading position in the global ultra-high-voltage (UHV) power transmission field.

Constructed by State Grid's subsidiary in Jiangsu Province and linking the cities of Suzhou and Nantong, the project boasts the world's ultra high voltage, extra large power transmission capacity and super long distance over complex landscapes.

Innovative technology also helped the UHV line cross through river tunnels.

The project adopts world-leading 1,000 kV GIL technology, bringing major technical innovation to the UHV power transmission field.

As a safe and flexible alternative to overhead lines, GIL is becoming more important as it produces less impact on the geological environment and less electromagnetic radiation.

A state-owned company established in 2002, State Grid supplies power to more than 1.1 billion people in China.

Representing the largest public utility in the world, State Grid also owns and operates overseas assets in countries including Australia, Brazil, Greece, Italy, the Philippines and Portugal.