CHINA’S economy will overtake that of the United States by 2035 and be twice its size by midcentury, a study released today by a US research organisation concluded.

The report by economist Albert Keidel of the Carnegie Endowment for International Peace said China’s rapid growth is driven by domestic demand more than exports, and will sustain high single-digit growth rates well into the 21st century.

“China’s economic performance clearly is no flash in the pan,” Mr Keidel said.

“Its growth this decade has averaged more than 10 per cent a year and is still going strong in the first half of 2008. Because its success in recent decades has not been export-led but driven by domestic demand, its rapid growth can continue well into the 21st century, unfettered by world market limitation.”

Mr Keidel said the rise of China to the world’s biggest economy will happen regardless of the method of calculation.

Under current market-based

Countries that require less energy per unit of GDP may fare better during a period of high energy prices.

This table shows the Kg of oil equivalent consumed per unit of GDP on a purchasing power parity basis for 32 countries, as reported by the United Nations.

This data is not a measure of energy use efficiency, because it does not distinguish between countries with high energy intensity industries (such as steel making) versus those with low energy intensity industries (such as software).

The data also does not indicate how much margin exists to be more efficient if necessary.

Interesting observations, include that the United States and China have similar energy consumption per unit of GDP, although the US figures probably include a much higher personal energy use component as part of the overall energy use.

Also, India uses only about 82% as much energy per unit …