The Nuozhadu Hydropower Plant, expected to become the largest hydro plant in southwest China's Yunnan province, put its first generator into operation on Thursday.

The first generator, which has a 650 megawatts capacity, is located in Pu'er city in the lower reaches of the Lancang River.

China Huaneng Group, the main investor in the project, said the plant will install nine 650 mW generators and will be able to guarantee annual electricity generation of 23.91 billion kilowatt hours per year.

The Nuozhadu dam has a maximum height of 261.5 meters.

The total investment could reach 61 billion yuan ($9.60 billion), Huaneng said.

The plant, which is one of the major power transmission projects from West China to East China, will also supply power to neighboring countries such as Laos, Vietnam and Burma.