01 November 2010

Front-end Nuclear Fuel Cycle

Front end Nuclear Fuel Cycle talks about the process of how uranium is mined from the very ground of the Earth, and then how it is being processes to make into Uranium Oxide or also known as yellow cake. However, today topic is not on the fuel cycle itself, but rather we are focusing much on the aspect of uranium abundances in the Earth.



As we can see in the picture below, we know that the current consumption is much lesser than the current usage of uranium in the world. Bt the question is how can this happen? This in short is because partly:

1) some country has started digging uranium long before NPP is founded.
2) the megatons to megawatts project which converts HEU (highly enriched uranium) into enriched uranium which can be used as fuel for power plant.



However, as we know, the current global power generated by nuclear power plant is roughly 6-7% of the total world power generated. Fossil fuel takes about around 80% of fossiel fuel consumption. So the question here arises is that are there enough uranium to fuel up for few hundred years before it run dry? This is to ensure that given the possibility of NPP to replace all fossil fuel, hence we can estimated the demand of uranium would increase at least 10 fold!!!. This shows that, if the current usage of uranium is 4.5million tonnes, per year by the time NPP take over all the fossil fuel, the demand will become 45 million tonnes per year. This is a huge number to worry about.

However, there are few reason why our group believe that uranium is not going to be depleted.

1) Nuclear price per tonne is still relatively cheap (less than USD80 per tonne).
Cheap price, means less $ goes into the R&D, which leads into less exploration to discover uranium deposits and also less mining of uranium ore. However, should the price rocketed to USD130 or more per tonne, we believe rigorous R&D will be poured into uranium searching, mining techniques and etc. This is because, its much more worth to mine uranium now as the profit margin obtained is so much higher.



2) Megatons to Megawatts Project.
This is a project whereby the US and the Russian has sign a pact to deplete their HEU into NPP fuels. And as we know HEU are at least 90% concentrated with U-235. Hence assuming perfect conversion of 3% enriched uranium-235, we can see that 1 tonne of HEU can produce 30 tonne of fossil fuel. So do imagine the number of enriched uranium we can get from this project.

3) Based on ecolo.org,

PROVEN Uranium reserves worldwide: about 4 million tons (current consumption rate of U worldwide is 60 000 tons per year => proven reserves at 80-130 $/kgU these proven reserves are enough for 65 years of use at the current consumption rate)

ESTIMATED Uranium reserves worldwide: about 16 million tons (current consumption rate of U worldwide is 60 000 tons per year => proven reserves at 80-130 $/kgU these proven reserves are enough for 265 years of use at the current consumption rate)

NON-CONVENTIONAL Uranium reserves worldwide (i.e. uranium contained in phosphates): an ADDITIONAL 22 million tons (representing an additional 365 years of use)

Uranium dissolved in sea water: about 4 billion tons (but more difficult and costly to retrieve)

Therefore, leaving aside the U in sea water, the total ESTIMATED + NON-CONVENTIONAL uranium reserves are enough for more than 600 years of use at current consumption rate using today's reactors and at a cost less than 80-130$/kg U (about twice today's spot price).

This shows that we have a long enough uranium supply for at least 8 generations. It should buy us enough time to discover other possible green fuels to supply our power plant by then.



4) Thorium as nuclear fuel.

Thorium is 3 times more abundant than uranium. However, according to world-nuclear.org, thorium can work pretty well in CANDU reactors ( Canada NPP which operates using normal uranium). Although currently thorium is not able to fissile on its own, if we can convert in into uranium 233 from thorium, we would also obtain a substantial amount of nuclear fuel. Do note that U-233 is as good as U-235 for nuclear power plants fuels.


1 comment:

  1. It is such a good article. If you need more information I have found this webpage talking about nuclear energy. It seems to be very complete, as well.

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