Photo taken on Oct. 19, 2020 shows the opening ceremony of the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

A participant views a compression system used in hydrogen fuelling station during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view a hydrogen production system exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view compressed hydrogen gas cylinders used in vehicles during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view hydrogen storage system exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view a hydrogen-powered drone exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view a fuel cell system exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Photo taken on Oct. 19, 2020 shows a hydrogen fuel-cell drone exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Participants view a hydrogen filling machine exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province, on Oct. 19, 2020. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)

Photo taken on Oct. 19, 2020 shows a hydrogen fuel-cell vehicle exhibited during the United Nations Development Programme (UNDP) Hydrogen Industry Conference in Foshan, south China's Guangdong Province. The UNDP Hydrogen Industry Conference 2020 kicked off here on Monday. (Xinhua/Deng Hua)