Physical Insights

An independent scientist’s observations on society, technology, energy, science and the environment. “Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.” – Carl Sagan

Posts Tagged ‘energy analysis

” Nuclear’s CO2 cost ‘will climb'”.

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The BBC is reporting that:

The case for nuclear power as a low carbon energy source to replace fossil fuels has been challenged in a new report by Australian academics.

It suggests greenhouse emissions from the mining of uranium – on which nuclear power relies – are on the rise.

Availability of high-grade uranium ore is set to decline with time, it says, making the fuel less environmentally friendly and more costly to extract.

A significant proportion of greenhouse emissions from nuclear power stem from the fuel supply stage, which includes uranium mining, milling, enrichment and fuel manufacturing.

Others sources of carbon include construction of the plant – including the manufacturing of steel and concrete materials – and decomissioning.

You can read the rest of the original BBC article here.

Perhaps more significantly, you can download the original academic paper in question here.

I will quote a couple of paragraphs worth:

Overall, the data clearly show the sensitivity of sustainability assessments to the ore grade of
the uranium deposit being mined and that significant gaps remain in complete sustainability reporting and accounting. This paper is a case study of the energy, water, and carbon costs of uranium mining and milling within the context of the nuclear energy chain.

In summary, the extent of economically recoverable uranium, although somewhat uncertain, is clearly linked to exploration effort, technology, and economics but is inextricably linked to environmental costs such as energy, water, and chemicals consumption, greenhouse gas emissions, and broader social issues. These crucial environmental aspects of resource extraction are only just beginning to be understood in the context of more complete life cycle analyses of the nuclear chain and other energy options. There still remains incomplete reporting however, especially in terms of data consistency among mines and site-specific data for numerous individual mines and mills, as well as the underlying factors controlling differences and variability. It is clear that there is a strong sensitivity of energy and water consumption and greenhouse gas emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium- to long-term. These issues are critical to understand in the current debate over nuclear power, greenhouse gas emissions, and climate change, especially with respect to ascribing sustainability to such activities as uranium mining and milling.

So, to summarise exactly what the paper says:

There are some inputs of energy  associated with the nuclear fuel cycle on a whole-of-life-cycle during uranium mining and milling, and in practice at present there are some carbon dioxide emissions associated with these energy inputs.

As reserves of easily recoverable high-grade uranium ore decline, assuming that the greenhouse-gas intensity of the energy inputs into the mining operations remain comparable, the whole-of-life-cycle greenhouse gas emissions intensity of nuclear energy might be expected to increase somewhat.

I think we already know that. Everyone already knows that.

The lead author of the paper, Gavin Mudd, is an Australian academic with a background in geohydrological engineering. He is a nuclear energy skeptic – well, not so much a nuclear energy skeptic as someone who is skeptical of the ecological sustainability of current uranium mining practices. His main area of expertise and interest with regard to nuclear energy is uranium mining.

I use the term “nuclear energy skeptic” because it’s reasonably clear that he’s anti-nuclear-energy – but I think it’s almost uncharitable and unfair to put an academic who puts forward their arguments in terms of reasonably well constructed academic papers in peer-reviewed science journals in the same category as the likes of Wasserman, Gunter or Caldicott.

This paper does not at all say “nuclear energy is unsustainable” or “uranium mining is unsustainable” – once the journalists apply a little spin to it, however, it’s easy to see how many could try and apply this paper, and especially press articles like the above, towards evidencing such a conclusion.

Describing the fact that there are energy inputs associated with uranium – which we already know – doesn’t answer the real question at all – How does the whole-of-life-cycle greenhouse gas intensity per MWh of electricity generation actually quantitatively compare to the whole-of-life-cycle greenhouse gas intensity of other energy generation technologies?

Sure – it’s somewhat reasonable to suggest that these quantities will change over the long term, into the future. Quantitatively, how will they be expected to change?

I should add, finally, that this paper is notable for being – perhaps – the first ever nuclear-skeptical study of the energy and greenhouse gas intensity of the nuclear fuel cycle that does not invoke the work of van Leeuwen and Smith. In fact, in terms of the quality of the source material cited, this paper seems pretty good.

The Energy Return of Nuclear Power

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Check out this recent post on The Oil Drum:

Storm Van Leeuwen this, Storm Van Leeuwen that, Storm Van Leeuwen the other thing. Since Storm Van Leeuwen said this, obviously that’s the facts, and that’s that.

But just in case the author had any credibility left over after writing that, it seems they threw in a Caldicott citation just for good measure.

Here are some of my favourite websites which deal with the energy analysis of the nuclear fuel cycle – suffice to say that every single one of them is pretty damning of the Van Leeuwen and Smith study. – Energy Lifecycle of Nuclear Power

Life-Cycle Energy Balance and Greenhouse Gas Emissions of Nuclear Energy in Australia – University of Sydney ISA group’s study [PDF link]

World Nuclear Association – Energy Analysis of Power Systems

Everyone should feel free to post a comment over there with your thoughts on the data used, and the conclusions drawn from it.

Written by Luke Weston

April 22, 2008 at 5:35 pm