(AP) -- China has overtaken the United States as the world's largest energy consumer, the International Energy Agency said Tuesday. China immediately questioned the report, claiming its calculations were "unreliable."
The Paris-based agency said China's 2009 consumption of energy sources ranging from oil and coal to wind and solar power was equal to 2.265 billion tons of oil, compared to 2.169 billion tons used that year by the United States.
The shift is historic, coming years ahead of forecasts. In climate change talks, China has long pointed fingers at the energy consumption patterns of developed nations and is sure to feel uncomfortable with the mantle of consuming more energy than any other nation.
China is also sensitive to complaints about its status as the world's biggest polluter and suggestions that its demand is pushing up energy prices on global markets.
According to the IEA statistics, China's energy consumption has more than doubled in less than a decade, from 1.107 billion tons in 2000 - driven by its burgeoning population and economic growth that hit 11.9 percent in the first quarter of this year.
Per capita, the United States still consumes five times more energy than China, IEA chief economist Fatih Birol told The Associated Press in an interview.
China's manufacturing and steel production are booming, and newly prosperous Chinese families, who a generation ago were subsistence farmers, are now buying air conditioners, home electronics and cars in record numbers.
The surge in energy consumption has turned China into the biggest source of climate-changing greenhouse gases. The government has pledged to curb the growth in its emissions, but has refused to adopt binding curbs, maintaining that pollution is an unavoidable consequence of the industrialization process.
According to the IEA statistics, in 2009, more than half of China's total energy came from coal, a heavy polluter that accounts for less than a quarter of U.S. consumption. Oil - the No. 1 energy source in the U.S., accounting for nearly half the total - made up less than a fifth of the Chinese energy total.
The Chinese Cabinet's National Energy Administration cast doubt on the IEA's statistics, according to a report Tuesday by the official Xinhua News Agency.
"IEA's data on China's energy use is unreliable," said official Zhou Xian, adding that the agency "still lacked understanding about China's relentless efforts to cut energy use and emissions, notably the country's aggressive expansion of new energy development."
The report cited data from China's National Bureau of Statistics that said China's energy consumption last year was equal to 2.132 billion tons of oil - less than the IEA figure.
Birol, the IEA's head economist, told The AP that the organization had used the same sources and methodology it always has in compiling the 2009 statistics, which he said were in line with the trend for the past decade.
"The trend is undeniable that the Chinese energy consumption is growing very strongly - which is very legitimate, by the way, considering their population - and the energy from the OECD countries, the U.S., Europe and Japan, is stagnating. They are two major undeniable trends," Birol said in a telephone interview. "There's nothing specific from this year, it's all the same methodologies we used before."
He was quick to emphasize that China's appetite for energy is consistent with the rise in its 1.3 billion-strong population and the growth of its manufacturing-based economy, which churns out half the world's supply of steel and is also a top producer of aluminum - another fuel-hungry industry.
He also emphasized China's status as the world's leader in wind and solar power and said the country was also making "major efforts" in nuclear power.
China has invested heavily in hydroelectric dams, wind turbines and nuclear power plants in an attempt to cut rising reliance on imported oil and gas, which its leaders see as a national security risk.
Still, coal, oil and natural gas are expected to account for most of China's energy supplies for decades to come.
The country builds dozens of new coal- and gas-fired power plants every year as it attempts to keep pace with double-digit annual increases in electricity consumption.
The country's flood of new office towers, shopping malls, hotels and apartment complexes are straining generating stations in cities, where demand exceeds supply - forcing the government to order rolling blackouts during the summer.
Improving energy efficiency is a key part of China's stimulus spending in response to the global downturn.
The communist government is in the midst of a five-year campaign to cut China's "energy intensity," the amount of energy consumed for each unit of economic output, by 20 percent from 2005 levels.
The government said this month it has reached the 16 percent mark after shutting down outmoded power plants, steel mills and other facilities. But authorities say China still consumes several times as much energy as the United States, Japan and other developed economies per dollar of output.
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