Availability of uranium and nuclear power
There are about 1012 tonnes of uranium in the top kilometre of the earth's crust. It is just as well that this is so, as the heat from the radioactive decay of uranium (and thorium) ores in the crust has kept the earth reasonably warm throughout the ages and prevented it becoming a cold and lifeless planet.
Uranium exists in a variety of mineral forms in concentrations that are mostly too low to be commercially exploitable. However, sufficient viable uranium ore deposits were discovered to feed the burgeoning military and civil nuclear programmes during the 1960s and 70s. There has though been little prospecting for new uranium deposits during the past two decades (see ‘Uranium - no longer mining's Cinderella' by Michael Forrest in Materials World, April 2005).
The need for ‘green' nuclear reactors
Nuclear reactors during their operating life do not generate carbon dioxide so the current concern about global warming may well result in an increase in the rate of construction of nuclear plants. However, should there be a large demand for nuclear generation, the nuclear industry will be forced to use leaner ores with the associated increased expenditure of energy in mining and milling. These mining processes will themselves produce greenhouse gases and there could come a point where the exercise becomes pointless. David Fleming expands this point of view in an article in the June issue of Prospect.
His argument is as follows. Currently nuclear power provides 16% of the world's electricity, but electricity production itself is only 16% of the total energy consumed globally. It follows that currently nuclear power is contributing only 2.56% to man's total energy needs. He argues that to make a significant impact on global warming nuclear would have to supply 100% of all the world's electricity requirements. However, should it do this, he calculates that the planets total quantity of viable uranium ores would last just six years. He further asserts that this figure would reduce to two years if nuclear power also generated sufficient hydrogen to power all of the world's transport.
Fast reactors could solve shortage of uranium
An immediate solution to the shortage of high-grade uranium ore would be to substitute thermal nuclear stations with fast reactors. This would increase the reserves of economically viable uranium ore by up to a factor of 100. Fleming rejects this on the grounds that fast reactors are not ‘technically feasible'. However, fast reactors have been operated successfully but are not employed because they are uneconomic at current uranium ore prices. The scenario proposed by Fleming would completely change this situation.
The availability of uranium ore still has military as well as civil implications. In the run-up to the Iraqi war British intelligence reported that Saddam Hussein had tried to buy significant quantities of uranium ore from Niger. This information was eagerly picked up by the Bush administration and the revelation became a pivotal point in President Bush's 2003 State of the Union address, although the reports have since been disputed.
The mining of metals plainly falls within our Institute's bailiwick, but should that metal be uranium, I urge you to tread softly.
‘Uranium - no longer mining's Cinderella', Michael Forrest, Materials World, April 2005
‘No more uranium', David Fleming, Prospect, 11 June 2005
President George Bush's 2003 State of the Union address