China's energy consumption per unit gross domestic product (GDP) increased a year-on-year 0.09 percent in the first half of this year while the energy consumption increased 11.2 percent compared with the same period last year, the National Bureau of Statistics (NBS) said Tuesday.

China's GDP grew by 11.9 percent in the first quarter this year, and by 10.3 percent for the second quarter of this year. In the first half of the year, the country's GDP grew by 11.1 percent, according to figures from the NBS.

The International Energy Agency (IEA) said China has gone from using 1.11 billion tons of oil equivalent in 2000, to 2.13 billion tons in 2008. Last year, China consumed the equivalent of 2.27 billion tons of oil and gas in 2009. By 2015, the IEA expects China to consume the equivalent of 2.78 billion tons of gas compared to US's 2.29 billion tons.

Last month, the IEA said China has surpassed the US to become the world's top energy consumer, a statement which China strongly denied.

The government pledged to improve energy efficiency by 20 percent between 2005 and 2010.

By 2009, the government said it had reduced energy use by nearly 16 percent relative to economic output, revising an earlier figure of 14.4 percent. By 2020, China promised to cut the amount of carbon emissions per dollar of economic output by 40 percent to 45 percent compared with the 2005 levels.

In May, Premier Wen Jiabao vowed to use an "iron fist" to reach the targets, and the government announced it would shut down inefficient factories.

The government's efforts will be focused on highly-consuming industries such as production of iron and steel, nonferrous metals, construction materials, coal and machinery.

"Energy consumption per unit decreased 2.69 percent in coal industry, 7.61 percent in building material, 1.64 percent in steel making and 4.28 percent in petrochemical industries over the January to June period," NBS said on its website.