China's carbon dioxide emissions dropped 1% in the first half of 2025 from the same period last year, helped by growing use of renewable energy to generate power, according to a study by the Helsinki-based Centre for Research on Energy and Clean Air. Emissions from the power sector, the top source of greenhouse gases in China, fell 3% during the six-month period, according to the study by CREA's lead analyst Lauri Myllyvirta for UK-based research organisation Carbon Brief.