China is on track to become the world's largest net oil importer, but when that will happen remains to be seen.

The US Energy Information Administration (EIA) predicts China's monthly net oil imports will surpass the US in October 2013 as it nears 7 million barrels per day, pushed by growing oil demand.

The forecast shows China's annual oil imports will eclipse those of the US by 2014. The surge comes as oil production increases amid flat demand in the US.

“US total annual oil production is expected to rise by 28% between 2011 and 2014 to nearly 13 million barrels per day, primarily from shale oil, tight oil and Gulf of Mexico deepwater plays. In the meantime, Chinese production increases at a much lower rate (6% over this period) and is forecast to be just a third of US production in 2014,” the EIA said.

“On the demand side, China's liquid fuels use is expected to grow by 13% between 2011 and 2014 to more than 11 million barrels per day, while US demand hovers close to 18.7 million barrels per day, well below the peak US consumption level of 20.8 million barrels per day in 2005.”

A recent report by Wood Mackenzie forecast Chinese crude oil imports will exceed those of the US by the 2017 time frame. The research consulting company predicted the country's oil imports could reach 9.2 million barrels per day by 2020, up from 2.5 million barrels per day in 2005. This is compared to 6.8 million barrels per day, down from 10.1 million barrels per day, for the US “This translates to a 360% increase in China crude oil imports and a 32% decline for the US.”

Steering China's rising demand for oil is the need for more gasoline as the number of people with vehicles increases. About 160 million vehicles are predicted to be on China's roads by 2020, according to Harold York, principal oils markets analyst for Wood Mackenzie. The number of vehicles is about eight times more than in 2005.

To meet the growing demand for crude oil, China will have to spend about $500 billion by 2020, according to the Wood Mackenzie analysis. The increased spend will come as the US contribution is set to fall from its peak of $335 billion to $160 billion, thanks to the rise in domestic supply coupled with lower demand.

“It is important to note these opposing trends as it means the US is becoming more North America-centric for its supply needs and China more dependent on Middle East and OPEC crude,” William Durbin, Wood Mackenzie's Beijing-based president of global markets, said. “We will therefore see OPEC suppliers, who traditionally focused on the US for crude sales, compelled to shift their focus towards China.”

The shift is expected to result in OPEC gaining a larger share of Chinese imports, possibly jumping from 52% in 2005 to 66% by 2020. The analysis also showed that the percentage of OPEC crude for the US will drop to 33%.

“The high cost to China for crude oil imports is compounded by the fact that China will pay a higher price for the imports relative to the US as the average price is based on a differential to Brent,” York said. “China's import crude price tends to be closer to Brent than the US, because of growing North America supply options.”

—Velda Addison