Tracing China’s energy flow and carbon dioxide flow based on Sankey diagrams

China has promised to optimize its energy structure and reduce its CO 2 emission in the 13th Five-Year Plan. To track the energy structure, the conversions, efficiencies, end consumptions of total energy and coal and the whole CO 2 emission status, the energy flow, coal flow and CO 2 flow in 2015 were, respectively, drawn at the national level based on Sankey diagrams. Besides, each provincial fossil fuel structure, CO 2 structure and CO 2 intensity were calculated and plotted. It is mainly found that China’s energy structure consisted of 69.2% of coal, 19.9% of oil, 6.3% of natural gas and 4.7% of non-fossil energy, where 45.5% of energy was consumed by industry and 23.9% by losses and statistical difference; coal was distributed to industry (55.6%), etc., with a utilization rate of 70.1%; and CO 2 were derived from coal (84.7%), oil (11.1%) and natural gas (4.2%), of which 39.0% was released through the process of thermal power generation and 19.4% by industry. The structures of fossil fuels and their CO 2 emissions together with the evolution of CO 2 intensity at the provincial level and the regional level were also given. Besides, two pieces of policy implications were proposed to provide the government with reference.