There is a complex nexus between GDP‐energy consumption and CO2 emissions, the causalities from energy consumption to CO2 emissions are observed generally, but there are some opposite relationships also. There are great differences in the carbon emissions, the efficiencies of energy use, carbon emissions of unit GDP and unit energy consumption between developed and developing countries. There is a large potential for carbon emission reduction in the developing countries through transforming the energy structure, improving energy utilization efficiency and controlling the total energy. To respond to global climate change, it is necessary to develop innovative technology for energy use, transform the energy structure and conduct the clean development mechanism. The fact that the largest CO2 emissions per capita have been produced by developed countries to date does not confirm the EKC hypothesis.
