China General Nuclear Power Corp began constructing its 2 million kilowatt solar thermal storage integrated project on Wednesday in Delingha, Qinghai province.

It is to date the solar thermal storage integrated project with the highest energy storage ratio in the country, the company said.

With a total installed capacity of 2 million kW, including 1.6 million kW of solar and 400,000 kW of photothermal salt storage capacity, the project has an energy storage ratio of 25 percent and can store energy for six hours, it said.

After the project is put into operation, annual power connected to the grid is expected to reach 3.65 billion kilowatt hours, it said.

The company's Delingha 50 megawatt solar thermal power plant in Qinghai, which is also China's first large commercial parabolic-trough concentrated solar power plant, was put into operation in 2018.

The operation of the solar power facility makes China the eighth country to have a large solar thermal power station. It is also a milestone for the company's solar-thermal energy development after more than 10 years of development.