"Thirteen million tons of coal withdrawn from reserves in three weeks is starting to look like a story too good to be true from the producers' perspective, but the data is fairly clear," Genscape said.
"The gap between shipments and consumption has not been as wide during the last four weeks of the year since Genscape started collecting transport data in 2005," the data provider pointed out.
HOUSTON, Dec 29 (Reuters) - Coal stockpiles at U.S. power plants fell 2.5 percent this week from last week as wintry weather widened the gap between shipments and consumption, Genscape said Tuesday.
Still, total coal inventory was 6.8 percent greater than the same week of 2008, the power industry data provider said.
Power generators had 172.1 million tons of coal on hand as of Tuesday, down from 176.5 million tons last Tuesday but up from 161.2 million tons the same week last year, Genscape said.
As of Tuesday, U.S. generators - which rely on coal to fuel about half of U.S. electricity production - had an average of 66 days' supply of coal on hand, assuming typical burn rates, down from 67 days the previous week, Genscape said.
Power companies as of Tuesday averaged 4 more days' of coal stockpiled than the same week last year, unchanged from last week's cushion over 2008 stockpiles, data showed.
"Thirteen million tons of coal withdrawn from reserves in three weeks is starting to look like a story too good to be true from the producers' perspective, but the data is fairly clear," Genscape said.
"The gap between shipments and consumption has not been as wide during the last four weeks of the year since Genscape started collecting transport data in 2005," the data provider pointed out.
Stockpiles could rebound next week as cold weather eases after boosting demand amid impeding deliveries in some regions, and total inventories remain much fatter than last year, Genscape said.
Inventories typically grow in spring and fall when demand for heating and cooling drops. Stockpiles usually shrink during summer and winter when demand rises for climate control in homes, stores and factories.
This year has been different. Due to the economic slowdown, coal inventory at the end of summer 2009 was unusually high, partly because drawdowns were weak and miners had geared up to ship more based on 2008 performance.
Mathematical rounding sometimes affects the results, overstating some changes and understating others, Genscape has said. (Reporting by Bruce Nichols; Editing by John Picinich)