Bob:
Firstly my apologies for not replying earlier, I really wasn't reading Harry Potter, but involved in a project that took my day.

I believe, if you go back over what I have written in the past you will find that I have spoken out several times about the need to have and enforce strong regulation of the coal industry. What I was trying to point out was that the apparent assumptions that we are running out of actual coal in the ground are using a definition of reserve that is transient and does not reflect the amount of coal that remains, and further that, as other fuels become more expensive to produce, so the definition of what is a coal reserve will likely expand again.

This will likely be more controlled by the economics of demand than new technology, but, and I used in-situ combustion only illustratively of this, new technologies or the improvement of old ones will also play a part in increasing what the reserves of the future are considered to be.

After reviewing recent information and other information over the past several years, I can't help but feeling that there is a major disappointment ahead for those who think that the future will involve dramatic increases in coal production. Production may be stable or rise gently, but perhaps that's about it. The United States, supposedly the "Saudi Arabia of Coal," is close to becoming a net importer of coal! One major obstacle to increasing production is laying enough rail to do so. Present coal-bearing railways are about maxed out. Efforts to put in modest new feeder lines -- in places like Wyoming -- have not been very successful. Proposals to put in a new coal line in a coastal region are laughed at. That could change, but that process of change and eventual construction could take a couple decades.

Also, unlike oil or gas, coal varies widely in quality. On a contained-energy basis, I believe it was noted that the US hit a peak of production in 1998, with lower quality cancelling out any production volume increases since then.

I've seen some estimates of eletricity "demand" that show a doubling by 2030. Makes sense if a lot of Indians and Chinese want to use electricity. This 100% expansion is expected to be provided primarily by coal and nuclear. If 50% of the expansion is provided by coal (reasonable), then world coal production would have to double. If the US is maxed out, and China will be maxed out by 2015 or so, where is this doubling going to come from?

Lastly, as the UK example shows, these coal resource estimates might turn out to be something like a fiction.

When I see maps such as the one above, and for renewable energy resources such as solar and wind, I am always struck by the east-west divide. Two regions, separated by a north-south strip a few hundred miles wide that is marginally habitable (and likely to be less so as GW decreases precipitation and the fossil aquifers are drained). I have to wonder how long it will be before the interests of the two regions diverge, perhaps sharply so.

Econ guy:
As I tried to show from the earlier surveys, there is actually some fairly reliable data on the size of the UK resource. The problem is confusing what is there (the resource) with what is economically and viably recoverable (the reserve). At present the economics are such that deep mined coal cannot compete with oil and gas as a fuel. As those fuels start down the back slope of the production curve coal is, in the short term, a likely replacement - because there already is an industry, it can be geared up, and for a number of uses equipment is already in place to use it. There are some technical and economic issues with using it in machines (such as cars) that use liquid fuels, but these routes (such as CTL) have been developed. Thus it is probable that more of the resource will again be considered as a reserve - which it is currently not. But it is the change in what is considered a reserve that has occured, not the overall size of the resource.