Explore Zhangjiakou Competition Zone of 2022 Beijing Winter Olympics (16)

Photo taken on March 18, 2021 shows the Zhangbei flexible direct current (DC) power grid project in Zhangjiakou, north China's Hebei Province. It is the world's first DC power grid and will be able to deliver about 14 billion kilowatt-hours of clean energy per year. The project will guarantee a 100 percent green power supply for the Beijing 2022 Winter Olympic venues. (People's Daily Online/ Zhou Yu)