Uranium Depletion and Nuclear Power: Are We at Peak Uranium? (Discussion, The Oil Drum)

[jpak]

http://www.theoildrum.com/node/2379

This is a guest post by Miquel Torres.

A recent post by Martin Sevior has invigorated the nuclear energy debate causing over 240 comments with the most diverse opinions. I would like to further pursue this debate, as the question of whether nuclear power can provide a big part of the worlds energy needs is extremely important in the Peak Oil debate, because it is the only alternative energy source beside coal providing the type of electricity production necessary for the current electric grid model: big, base-load capable power plants. If that role is fulfilled, the current electricity production system can continue beyond Peak Oil, and even expand to provide the energy necessary for electrified transport. If it falls short, a new energy model is needed.

<much more>

[happyslug]

1. Remember Uranium is the second most common element on earth

Iron is number one. The biggest problem with uranium is most of it is in the Earth's core. Uranium is rare in the earth's crust. The big problem with Uranium is it can occur anywhere for it is a basic element and thus pushed into the crust from underneath (Via Volcano or where the earth crust if forming as the tectonic plates move around).

Now carbon based energy (Coal, Natural Gas and Oil) was formed from biological creatures settling on the ocean floor and over time being covered and by the action of the overburden converted into oil, Natural Gas or Coal. Since these Carbon Energy forms came from the SURFACE to where they are now we have a good idea where they are (or can be). Thus we have a Good idea of how much oil, coal and Natural gas exists on the plant. We do NOT have the same level of knowledge as to Uranium. We may have peaked, we may be centuries from peaking. We just do NOT know. In many ways as to Uranium we are in the situation the oil industry was in in 1900, the oil industry knew where some oil was, but did not know how much oil wa left for the oil industry did NOT have a good idea of where oil could be found. By 1930 the Oil Industry did know (and some people said by 1910) where oil could be found (But took another 40 years till the 1960s for most areas where oil could be found to have been explored, thus it is only in the 1960s that Oil industry finally had a feel for how much oil was in the world).

The Uranium industry is in much of the same dilemma the oil industry was in 1900. We know they MUST be a limit, but what that limit is is unknowable at the present time do to lack of data. Example so that lack of data include a report I have read that a hot spot for the search for Uranium is Iran, but the amount I unknown at the present time (Australia holds the present title for most Uranium known).

In Short, the data on where Uranium is and is not is weak since it can be VERY deep in the earth's crust (and can be found in Outer space also). Thus, unlike oil where we have a good idea of how much oil in left, we just do NOT have such confidence in how much Uranium is left.

[eppur_se_muova]

2. SECOND most abundant? hardly.

http://en.wikipedia.org/wiki/Uranium#Occurrence

http://en.wikipedia.org/wiki/Element_abundance

http://en.wikipedia.org/wiki/Cosmochemical_Periodic_Table_of_the_Elements_in_the_Solar_System

on edit: There is a controversial theory that there may be a large amount of U in the Earth's core, but there is very little evidence to support this. In fact, it appears that most of the Earth's radioactively generated heat is accounted for by the decay of U, Th, and K (potassium), assuming only the more widely accepted values for the abundance of U and Th:

http://www.newscientist.com/article.ns?id=mg18725103.700

http://www.physlink.com/News/121103PotassiumCore.cfm

[happyslug]

3. I like Wikipedia, it provides a could starting points, but it has errors

As Colbert has shown several times.

For more on Uranium see:
http://www.uic.com.au/nip78.htm
http://www.uic.com.au/nip75.htm
http://www.du.edu/~jcalvert/phys/uranium.htm

While most Scientists seems to reject the theory, a good many do accept it, and a test has been proposed to to see if it is true:
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2004/11/29/MNGPIA17BL45.DTL&type=printable

Anyway, none of this has to do with my premise, Uranium is a NON-CARBON form of energy. The existence of Uranium does NOT depend on having had living things capture the energy of the Sun and over time converting that energy to Oil, Natural gas or coal. You do NOT have the 20,000 feet limitation on Oil (Below 20,000 feet Oil is converted to Natural Gas, thus you have Natural Gas well going down 50,000 feet, but oil wells all stop at 20,000 feet). Coal is also NOT that far from the surface of the earth (and most Natural Gas is found either with Oil or when looking for oil and thus less than 20,000 feet deep).

The opposite is true of Uranium, Uranium NEVER has had to be at the surface. Thus how much Uranium that can be found and extracted is less knowledgeable than the more common and closer to the surface Carbon based energy sources.

[eppur_se_muova]

4. Check the fourth link I posted, they are already doing the measurements needed.

Note this is a 2005 paper, so they are probably familiar with the debate. (Note I rely on these papers more than the Wiki entries, since Wiki doesn't really adress the composition of the core anyway.)

Some of this heat comes from the decay of radioactive elements. Based on studies of primitive meteorites known as carbonaceous chondrites, geologists have estimated Earth's uranium and thorium content and calculated that about 19 terawatts can be attributed to radioactivity. But until now there has been nothing definitive about exactly how much uranium there is in the planet, says geologist Bill McDonough of the University of Maryland in College Park. "There are fundamental uncertainties."

Now, the KamLAND antineutrino detector in Kamioka, Japan, has counted such antineutrinos. An international team of scientists analysed the data and found about 16.2 million antineutrinos per square centimetre per second streaming out from Earth's core. They calculate that the nuclear reactions creating these particles could be generating as much as 60 terawatts, but are most likely putting out about 24 terawatts (Nature, vol 436, p 499). "We have made the first measurements of the radioactivity of the whole of Earth," says John Learned, who heads the KamLAND group at the University of Hawaii in Manoa. The KamLAND group's finding is like unwrapping a birthday present, says McDonough.

Taking the most extreme possibility, a figure of 60 TW would indicate that possibly U is several times more abundant than previously believed, or that induced fission is ongoing, but necessarily involving a much smaller amount of material. I don't think the upper bound allows the possibility of a very large mass of U at the core -- maybe more than was postulated earlier, but not hugely more.

The fifth link I posted indicates there's some reason to suspect K, more than U, is responsible for any anomalously high readings.

We can't mine the Earth's core, but its heat and radiation signatures should give us a better idea of what's down there.

There may be uncertainties about the total amount of U present in the Earth, but not as much doubt about how much is accessibly near the surface. Finding a mass of U at the core helps nobody, in terms of meeting energy demands.

(PS: Herndon mentions a mass about 8km in radius. That would still be an extremely small quantity compared to O, Si, Al, Na, K, Ca, Fe, Al, Fe, Mg, Ti, by a factor of many thousands. That's a really far cry from being the second most abundant element.)