China has rejected an assessment by the International Energy Agency that it had overtaken the US to become the world's top energy consumer."The IEA's data on China's energy use is unreliable," said Zhou Xian, director-general of the General Affairs Department of the National Energy Administration (NEA).Zhou was referring to IEA claims that China consumed 2.252 billion tons of oil equivalent (toe) of energy in 2009, a figure that would put China about 4% ahead of the US in the use of energy sources including coal, nuclear power, natural gas, and hydroelectric power.Zhou claimed IEA lacked understanding about China's efforts to reduce energy use and emissions, notably the country'...