China National Petroleum Corp (CNPC), the country's largest oil and gas producer, has used gas from its stockpiles to meet the rising demand for winter energy, company sources said on Wednesday.

The company took 5.7 million cubic meters (cu m) of gas from its Dagang storage facility in Tianjin on Nov 15, and then used a further 8 million cu m on Tuesday, because of extra demand for heating in Beijing and Tianjin, CNPC said.

Dagang and the newly built Huabei stockpiles currently hold 1.963 billion cu m of gas, 8 percent more than a year earlier, it said.

The Dagang store holds China's largest underground reserves and can be tapped to meet peak seasonal demand, or when pipeline supplies are disrupted, said the company.

Several of CNPC's gas pipelines are now operating at full capacity to meet the increased demand.

The company's Shaanxi-Beijing gas pipelines, West-East gas pipeline, and Qinghai-Ningxia-Gansu gas systems have all been at full capacity since Oct 10, according to Fan Li, an official with CNPC's Beijing oil and gas control center.

The company's daily gas transmission volume has now reached 120 million cu m, according to CNPC.

Its gas imports from central Asia have also attained maximum contract volume, said the company.

CNPC has also accelerated construction of gas storage facilities to enhance its supply capacity.

It has started feasibility studies for two facilities along the second West-East gas pipeline which links central Asia and China's eastern regions, the Beijing-based company said on Wednesday.

Sinopec Group, the country's other oil and gas major, has also taken efforts to increase gas supply, especially in the southwestern regions.

The company says it will supply 1.4 billion cu m of gas to Chengdu this year, compared with 800 million cu m in 2005.

It will also drill more than 10 gas wells in the southwestern regions to increase production capacity.

China is not expected to see a widespread gas shortage this winter, as domestic companies have made early preparations to add supply having learned the lessons from last year's shortages, said industry insiders.

The country was hit by severe gas shortages during an unusually early and cold winter in 2009, prompting factories to reduce, or even suspend, production to divert gas to heating for residents.

Wang Zhen, director of the Business and Management School at China University of Petroleum, told China Daily that last year's gas shortage will not be repeated.

Hu Weiping, deputy director of the Oil and Gas Department of the National Energy Adminstration, told China Energy News that the government had asked China National Offshore Oil Corp, the country's largest offshore oil and gas producer, to secure gas from international markets to supply to Shanghai, the country's financial hub. By doing so, it will free up domestic gas for emergency needs.

"I believe gas supplies this winter, though still slightly tight, will be able to meet the demand," Hu was quoted as saying.