BEIJING China on Tuesday disputed that it had surpassed the United States last year to become the world's largest energy user, and defended its efforts in boosting cleaner energy sources.
The International Energy Agency estimates China last year consumed 2.265 billion tonnes of oil equivalent of energy from sources including coal, oil, natural gas, hydro and nuclear power, 4.4 percent more than the United States.
But Zhou Xian, spokesperson for China's National Energy Administration, said on Tuesday that the IEA's estimate of China's energy consumption was too high, although he declined to give an alternative estimate.
The IEA estimate, he said, "could be used as a reference but is not very credible".
"We believe that (IEA) did not understand fully the Chinese situation, in particular the efforts China made in energy saving, emission reductions and development in new energy sources," said Zhou.
The IEA, adviser to 28 industrialized countries, is not the first provider of energy statistics to say China has become the top energy user.
According to BP Plc's Statistical Review of World Energy, released in June, China including Hong Kong overtook the United States last year, using 2.20 billion tonnes of oil equivalent of primary energy compared with 2.182 billion tonnes.
Zhou said China was still revising last year's energy data, but already released figures suggest it will take barely a year for China to overtake the U.S.
Data from a 2009 forecast by the U.S. Department of Energy and the IEA showed China would not surpass the U.S. until 2015.
China's energy use has doubled since 2000 while that of the United States has fallen slightly, according to the IEA's latest figures.
"The most surprising thing is not that China overtook the United States in 2009, the most important thing is the fact that 10 years ago the U.S. was consuming twice the energy that China was consuming," IEA Chief Economist Fatih Birol told Reuters. "Ten years is not a very long period of time."
"The internationally accepted definitions indicate that China surpassed the U.S.," he said, when asked to comment on China's denials.
China's rise to the top ranking was faster than had been expected in part because the United States has outpaced China in improving energy efficiency measures over the past decade.
Dai Yande, deputy head of China's Energy Research Institute, a top government think-tank on energy policy, called the comment lacking "basic knowledge of energy".
"This kind of comparison is ludicrous. The U.S. has completed its industrialization phase and China is in the middle of rapid industrialization," said Dai. "This is a totally wrong analysis."
China's energy demand growth also largely braved the global financial crisis that hit the United States and Europe, with imports of coal and crude oil both hitting a record and power consumption up 6.3 percent spurred by a runaway property sector.
The NEA spokesperson Zhou added that China has already exceeded the United States in the pace of new energy utilization.
China has the world's largest installed capacity of hydropower, the largest solar use for water heating, the largest capacity of nuclear power generators under construction and the fastest growth in wind power development, he said.
China's National Energy Administration expects total primary energy consumption to reach 4.2 billion tonnes of standard coal by 2015, with coal itself contributing 2.67 billion tonnes to the total. or 63.6 percent, state media reported in June, a share down from 70 percent in 2009.