FUZHOU -- China's first nuclear power unit using Hualong One technology, a domestically developed third-generation reactor design, has completed a key test, according to China National Nuclear Corporation (CNNC).

The successful hot functional test on the power unit, which was completed in the eastern Chinese city of Fuqing, marked an important step in the development of the unit before the process of fuel loading, according to CNNC.

Hualong One reactors were jointly designed by two nuclear power giants, China General Nuclear Power Group and the CNNC, and passed inspection by a national panel in August 2014.

The nuclear power unit, which began construction in 2015, is expected to start operation this year.

At present, CNNC has five Hualong One nuclear power units under construction.