Photo taken on Jan. 30, 2021 shows the No. 5 nuclear power unit in the city of Fuqing, southeast China's Fujian Province. China's first nuclear power unit using Hualong One, a domestically-designed third-generation nuclear reactor, has entered commercial operation, said the China National Nuclear Corporation (CNNC) Saturday. The No. 5 unit in Fuqing is generating electricity for sale after a seven-day trial run. (Xinhua/Lin Shanchuan)