Reuters quoted Genscape as saying that coal supplies at US power plants this week fell 1% from last week but are 20.2% greater than the same week of 2008. Electric companies had 177.2 million tonnes of coal stockpiled, compared with 178.9 million tonnes reported last Tuesday and 147.4 million tonnes the same week last year.

The industry data provider said that US generators as of Tuesday had an average of 66 days' supply of coal, assuming typical burn rates. That equals last week's coal burn capacity.

Genscape said that as of Tuesday, power plants had 11 more days' supply than the same week last year. That is equal to last week's margin over 2008 stockpiles.

It said that "Cooling demand is luring coal-fired units back into production, especially in the Gulf and Southeast, where temperatures have been extreme this season. But the demand increase is nibbling away rather than taking out large chunks of the large surplus built up over the last months. Despite sharp cuts in production of coal in response to weak demand, it is a virtual certainty that US coal reserves at the end of summer will be larger than last year.

It added that US coal stockpiles usually grow in the spring and fall, when mild weather eases cooling or heating demand. Stockpiles shrink as summer or winter sets in across the country, boosting demand for electricity for cooling or heating. Mathematical rounding sometimes affects the results, overstating some changes and understating others.

(Sourced from Reuters)