Friday, 28 March 2008

Expansion at Olympic Dam means increased energy inputs (of course).

Apparently, some people out there are shocked with new projections that expanded operations, proposed to be completed around 2013, at BHP Billiton's Olympic Dam facility will entail significant expansion of the mine's electricity consumption - projected to be an average of 690 megawatts per year, or around 40% of South Australia's total electricity consumption, when the expansion is complete.

Here's the complete story, from

(As an aside, I'm quite pleased to note, when reading the comments on the above-linked webpage, just how much pro-nuclear-energy sentiment seems to be out there.)

Olympic Dam is a copper mine. When the expanded production reaches full capacity in 2015 or so, 450,000 tons of copper metal will be produced annually.

There is a little bit of uranium, gold, and a couple of other things mixed into the orebody which are valuable too, so they extract them as well when the copper ore is processed.

It's a homogeneous orebody - the uranium and copper and things are all mixed together, so it is impossible to mine the copper without mining uranium, too.

For that 450,000 tons of copper metal that will be produced, only about 14,000 tons of uranium oxide will be produced. The uranium is only a byproduct.

Remember - without copper being mined out of the ground, no electricity of any kind, clean, green or not, can be generated, distributed or used. Without production of aluminium metal, a popular target of so-called environmentalists, electricity transmission over overhead cables cannot be done.

Even since the stone age or the bronze age, mining has been integral to the existence of our technological civilisation. Even as we move to clean sources of energy to power our technological civilisation, such as geothermal and nuclear energy, mining will always be essential.

Now, the expanded mine will consume 690 megawatts of electrical power, on average.

A typical nuclear power reactor generating 1 gigawatt of electricity requires an amount of uranium fuel corresponding to about 200 tons of natural uranium in the form of uranium oxide per year.

So, Olympic Dam will consume 690 megawatts of electricty - and it will produce enough uranium in one year to generate 70 gigawatts of electricity for one year -
over one hundred times the total power consumption of the mine.

Yes, you might be thinking that this ignores the other energy inputs into the nuclear fuel cycle - but it also assumes an extremely inefficient once-through fuel cycle using low-enriched uranium in current light water reactors, without recycling of fuel.

Of course, one must remember that the vast majority of the energy input at Olympic Dam goes into the extraction and smelting of copper metal - the overall "energy gain" typically associated with actual uranium mining operations are typically much higher than 100.

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