Jan. 23 (Bloomberg) -- China has shut about 5 percent of its coal-fired power plants, forcing 13 provinces to ration electricity as snowfalls and transportation delays hamper deliveries of the fuel.

The five biggest electricity producers have shut 90 power stations with combined capacity exceeding 20,000 megawatts in northern and central China, figures today from the State Grid Corp. of China show. Coal stockpiles at the plants have dropped below the ``caution line'' of three days' requirements.

China, the biggest coal producer, burns the fuel to generate about 78 percent of its electricity. Railway congestion as millions of Chinese travel before the Lunar New Year holiday, and heavy snowfalls have contributed to the lack of coal, said Chang Jianping, deputy director of market regulation at the State Electricity Regulatory Commission.

``It's not insufficient production that's leading to a lack of coal,'' Martin Wang, an analyst with Hong Kong-based Guotai Junan Securities HK Ltd., said by phone. ``Short-term transport bottlenecks caused by bad weather conditions and hoarding of the fuel by some sellers are to blame.''

As many as 13 provinces nationwide, including Hunan, Hubei, Sichuan, Jiangxi, Guangdong, and Tibet, are rationing power use because of the coal shortage, State Grid Corp. said in postings on its Web site.

``This could be the nation's worst power shortage in history,'' said Chang.

Guizhou Blackouts

As many as 17 counties in the northeastern part of Guizhou province are suffering blackouts as heavy snow and freezing temperatures damaged transmissions lines, Xiao Peng, vice president of China Southern Power Grid Co., said by phone today. Guizhou has 56 counties, according to the province's Web site.

``It is a natural disaster hit by the worst weather conditions in 50 years,'' Xiao said.

Southern China has shut 10,300 megawatts of power capacity because of coal shortages, Xiao said last week.

The country had thermal power plants with 554,420 megawatts of combined capacity by the end of last year, accounting for 77.7 percent of potential generation, according to the China Electricity Council.

``If the coal shortage worsens, it will pose a severe threat to the security of electricity grid operations,'' the commission said in a statement in its in-house newsletter yesterday.

Net Importer

China will become a net coal importer of 18 million tons in 2008, UBS analysts led by Ghee Peh in Hong Kong said in a Dec. 6 report. Exports dropped 16 percent and imports jumped 33 percent in 2007, leaving the nation with 2 million tons of net exports, according to customs data.

Heavy snow has disrupted road, rail and air transport in central and eastern China, the official Xinhua News Agency said Jan. 21, citing provincial officials.

Power lines from the Three Gorges hydro-electric dam in central Hubei province to Shanghai were damaged in the snowstorms, the agency reported, without saying when electricity is expected to be restored to the area.

About 179 million people will journey by train during the 46-day Chinese New Year season that started today, an increase of 8.3 percent from a year earlier, Wang Yongping, a spokesman for the Ministry of Railways, said this week in Beijing.

``It is difficult to predict when electricity supply will improve, as that has a lot to do with the weather conditions,'' the electricity commission's Chang said.

Shortage May Ease

The coal shortage may ease after March, Guotai Junan's Wang said.

Coal mines should increase supplies to ensure there is adequate fuel during the holiday, the country's top economic planning body said today.

Coal-producing provinces may not limit coal sales to other regions and mines will be punished for any random price increases, the National Development and Reform Commission in Beijing said. It ordered transport departments to boost thermal coal shipments.

Local governments should strengthen power-supply management and give priority to residents and utilities, the commission said in a statement.

To contact the reporter on this story: Wang Ying in Beijing at ywang30@bloomberg.net;

Last Updated: January 23, 2008 05:33 EST