I hadn't seen your thread before, lsayre. Same PDF too!
Didn't look like anyone had explained the discrepancy on your thread between the data in that PDF on US recoverable reserves (60 M) vs PA DNR estimate of 12 billion tons, which I haven't seen, but will research. That's 60 M vs. 12 --it's off by a factor of 200.
The difference is all in the word "recoverable', which really means economically recoverable. In Eastern Pennsylvania there quite likely are 12 billion tons of what would fall into the statistical range of coals with properties that warrant the title "anthracite". Of those 12 billion tons, only 60 million tons are likely to be economically recoverable, as well as of a level of purity and quality that warrant such recovery. The rest is truly there, but would only be extractable and purifiable with great difficulty and at ridiculously great expense and/or danger (so for all intent and purpose it is not viably recoverable).
The same is true for all grades of coal. When the government tells us that there are 350 or so years worth of coal remaining in the USA, that statement is only true under the context that it is undeniably there and measurable. It is a purely empty statement that is only meant to make us feel good. It says only that it is there, and it says nothing about our ability to economically recover it for any practical real world use. It is also generally prefaced by the line "at current rates of consumption" (as in: "at current rates of consumption there are an estimated 350 years of coal remaining in the United States."). The term "current rates of consumption" completely degrades the value and significance of the empty contention that 350 years worth of coal remain. For example, if we actually ever actually decided to use our coal reserves in order to 100% replace foreign oil (and yes, oil can be made from coal) then our real rates of consumption would easily go up a hundred fold or more, reducing the 350 years of reserve of coal to a mere 35 years of reserve or less.[/quote]
Holy cats, there is a lot more than 60million tons of Anth in the NEPA. http://www.eia.gov/energyexplained/inde ... l_reserves
Somewhere between 6 and 10 billion tons demonstrated reserves.