BEIJING -- In a move that could further fuel tensions in the South China Sea, China will step up exploration for methane hydrate, which is drawing attention as a future source of energy.

Research last summer led to the discovery of a high-purity methane hydrate reserve in the northern part of the South China Sea, according to the Land and Resources Ministry. The reserve, sitting off the coast of Guangdong Province, is estimated to span 55 sq. km and amount to the equivalent of 100 billion to 150 billion cu. meters of natural gas.

China will further explore the reserve, which it believes to stretch to the south. Domestic experts estimate that the body of water has methane hydrate reserves equal to 68 billion tons of crude oil, a figure amounting to 130 years of the country's energy consumption.

The Chinese aim to make methane hydrate commercially viable around 2030, seeing it as a promising means of coping with surging domestic demand for energy.

The nation also seeks to reduce its dependence on energy imports. China relies on imports for nearly 60% of its crude oil needs, making it the world's No. 2 importer by volume, after the U.S. For natural gas, the share of imports rose past 30% for the first time in 2013.

Methane hydrate is also expected to aid China's efforts to shift to natural gas from coal, which accounts for nearly 70% of its primary-energy consumption.

As China widens its search for methane hydrate in the South China Sea, it may create more frictions with such countries as the Philippines and Vietnam, with which it is embroiled in territorial disputes there.