US coal supply rises 0.7 pct - Genscape

CHICAGO, Sept 29 (Reuters) - Coal supplies at U.S. power plants rose 0.7 percent this week from last week and were 25.2 percent greater than the same week of 2008, Genscape said Tuesday.

Generators had 180.8 million tons of coal on hand, compared with 179.6 million tons last Tuesday and 144.4 million tons the same week last year, the power industry data provider said.

U.S. generators as of Tuesday had an average of 68 days' supply of coal assuming typical burn rates, Genscape said. That is equal to last week's estimated coal capacity.

As of Tuesday, power plants had 14 more days' supply than the same week last year. That is equal to last week's cushion over 2008 stockpiles, the data showed.

"Coal stocks are increasing, as they should this time of year, but at a slower pace than expected," Genscape said.

Deliveries have slowed to all regions, but burn, while anemic, has not dropped as fast. Utilities are using coal plants to relieve hard-working nuclear units, Genscape said.

East North Central saw the largest stock increase as consumption in the area is especially weak and the fall in burn is outpacing the decline in shipments of coal.

U.S. coal stockpiles usually grow in the spring and fall, when mild weather eases cooling or heating demand. Stockpiles typically shrink during summer or winter, which tend to boost power consumption for air-conditioning or heating.

Mathematical rounding sometimes affects the results, overstating some changes and understating others, Genscape has said. (Reporting by Bruce Nichols; Editing by Lisa Shumaker)