• A 'typical' hard coal powerplant: 8.5 TWh electricity from 2.5 million tons, that's about 0.3 kg mined for 1 kWh.

• The most recent German brown coal (lignite) powerplant: 1.3 TWh electricity from 1 million tons, that's 0.77 kg mined for 1 kWh.

• With the 'current average' ore grade of 0.15%, a current modern plant extracting energy for 45,000 kWh electricity from 1 kg, we get 0.15 kg mined material for 1 kWh.

• With the 'current average' ore grade of 0.15%, and an EPR expectation of 60,000 kWh electricity from 1 kg, we get 0.11 kg mined material for 1 kWh.

• With current peak grade of 0.05% and the EPR, we get 0.33 kg mined for 1 kWh.

• With a cutoff grade of 0.02% and the EPR, we get 0.83 kg mined for 1 kWh.

• With a 0.0004% grade granite and the EPR, we get 41.7 kg mined for 1 kWh.

For 2004, I find total global coal production was 5.524 billion tons, of which three-quarters, around 4.1 billion tons went for the production of 39.8% of a global electricity generation of just under 15,000 TWh, that is around 6,000 TWh. This gives an average of 0.68 kilograms of coal for 1 kWh. The figure is closer to the German brown coal power plant's figure I gave not because of the dominance of low-grade borwn coal (it is less than a fourth) but that of old inefficient plants. If we expect increasing efficiency for nuclear (EPR and all), we can also safely predict increased efficiency for coal, say to 0.55 kg giving 0 kWh.

For Uranium grades, current production (which is insufficient for current needs once material from decommissioned weapons runs out 5-7 years from now) seems to go rarely below 0.1%. (The current maximum is a staggering 18% at a Canadian mine, the minimum 0.035% at a Namibian mine.) But IAEA considers recoverable proven reserves those below $135/kgU, while most production is below $50/kgU. For a greatly broadened share of nuclear, these (and probably even more expensive) reserves have to be tapped. Unfortunately, in my current search I haven't found numbers on the grade of proven reserves close to $135/kgU, only found single examples that trend to above 0.01%.

At any rate, the figures for mined tonnage for coal and greatly increased non-breeder, non-thorium nuclear are in the same range.

_{*Lunatic*, n.
One whose delusions are out of fashion.}

this process is documented for air travel in the book Harry S Truman and the War Scare of 1948 -- heartily disliked by Truman hagiographers -- in which much epistolatory and other documentary evidence strongly suggests the unwillingness of the aircraft industry to scale back after its mega-lucrative WWII years and the consequent creation of mass-market passenger air travel (as well as the great Soviet Fear Campaign that launched the McCarthy ear).  similar critiques have been made of the so-called Green Revolution period as one in which the affluent N Hemi made a concerted assault on traditional agricultural methods and heirloom cultivars worldwide in order to create markets for a glut of chemicals, tractors, patented seeds and the like.  Manning and others have documented the ways in which the glut of fossil-intensive maize produced in the US exercised a warping effect on the market in sweeteners and cattle feed, even pressuring the FDA to alter the definition of "grade A" beef (Pollan and others) to conform to the  fat-saturated beef from cornfed cattle... and so on.  production driving demand creation, market theory standing on its head and kicking its feet in the air.

in other words, a lot of what we now take for granted as cultural and consumption patterns are the result of market-creation specifically to absorb overproduction, overproduction goosed by massive fossil inputs.  in just a few short decades we have gone from "having so much oil they had to invent ways to get folks to buy more of it" to "ooops, it's starting to run out."

this seems like good news and bad news.  the good news is that a lot of these patterns aren't really necessary:  fertiliser is way overused and could be replace by more intelligent soil cultivation, pesticides are far less effective and more self-defeating than they were sold to be and traditional/modern IPN techniques often work better;  less tractoring is required on most farms than the vendors of tractors and fuel have been telling everyone for decades.  many consumption patterns that were engineered to absorb a crisis of overproduction, could easily (in a physics sense) be reduced/retooled without enormous changes in effectiveness and in many cases with positive results for efficiency, health, etc.  the real issue is as J describes above, cultural:  many of these behaviours and patterns have now become acculturated to the point where people will endorse violence up to and including war and occupation rather than relinquish them.

unfortunately war and occupation are themselves enormous sinkholes of energy and raw materials, so the diminishing returns effect we see in exploiting lower grade ores or oil fields also applies to the theft of higher grade resources at gunpoint...  at some point it costs more to steal the goods than the goods are worth.

the diminishing returns on lower grade ore, and the yield per kg mined, referenced above, to me have serious carbon-neutrality implications.  this kind of mining is done with fossil-fueled heavy equipment -- much of it exempt from air quality regs.  as the yield reduces towards the lower figures in the list, the carbon emissions from the mining and refining process presumably scale up linearly.  as well as "KWH yield per kg mined" and the associated environmental devastation caused by getting at those ever-multiplying kg of ore, I'd sure like to know about gallons of fuel burned and ghg emissions per tonne of ore extracted, transported, and refined.  without all these numbers in hand it is hard even to say whether nuke power is a break-even proposition in carbon emissions.


The difference between theory and practise in practise ...