Carbon offsetting of uranium mines?

Below is an article I wrote for the South Australian Mines and Energy Journal on carbon emissions of uranium mines. (This, and others in the SACOME series, have also been published by my co-author, Ben Heard, on DecarboniseSA.com). This is a new version of a blog post I published on BNC a few years ago — but streamlined, simplified and updated. I hope you find it useful.

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South Australia is host to the single largest known deposit of uranium in the world, at Roxby Downs. The recent plans to massively expand production at its Olympic Dam mine will take uranium production from 4,000 tonnes of uranium oxide (tUO2) in 2010-2011 to 19,000 tUO2 by the early 2020s. This enlarged open-cut polymetallic mine, run by BHP Billiton, will also produce 730,000 tonnes of copper (the principal product) and 25 tonnes of gold.

Some environmentalists have objected stridently to this plan for an expanded mine, including Greens MLC Mark Parnell who said: “Our state risks being left with a huge carbon black hole as we become the greenhouse dump for one of the world’s richest companies“. Such hyperbolic claims are easily made and can sound persuasive. But are they be supported by evidence? Let’s consider the accuracy and context of such an argument from a climate science perspective.

The greenhouse gas emissions from the mine expansion will come predominantly from heavy use of diesel and other liquid fuels for vehicles and mining equipment, and a 650 MW increase in electricity demand (likely gas powered), including the supply of 200 ML/day of desalinated water to the site. The result is that carbon dioxide equivalent emissions could peak at 4.7 million tonnes per year (tCO2-e). The Environmental Impact Statement acknowledged this would add almost 10 per cent to South Australia’s forecast emissions in 2020 under a business-as-usual scenario.

Now, let us consider the net effect of this on global greenhouse gas emissions.

The uranium from the expanded mine will fuel nuclear power plants in countries like the U.S., France, U.K., South Korea, China and Japan, to be used for electricity generation. A modern 1,000 MWe thermal nuclear reactor requires about 170 tUO2concentrate each year, in order to fabricate 16 tonnes of slightly enriched fuel rods. This plant will then produce 8,000 gigawatt hours (GWh) of reliable, on-demand electricity, used to directly displace baseload coal or gas.

This means that the 19,000 tUO2 from the expanded Olympic Dam mine will provide enough fuel for a year’s operation of 112 GWe of nuclear power, which will generate about 900,000 GWh of electricity that releases no CO2 or other atmospheric waste like sulphur, soot and heavy metals. To put this in perspective, all of Australia’s power stations sent out 242,000 GWh in 2009.

One of us (Prof. Brook) recently published a meta-review in the peer-reviewed journalEnergy which estimated the full life-cycle greenhouse gas emissions for coal, gas and nuclear power electricity generation. This work puts emissions from a typical pulverized fuel coal plant at 915 tCO2-e per GWh, compared to 470 tCO2-e for a combined-cycle natural-gas plant, and 20 tCO2-e for a nuclear plant. Some of the full life-cycle emissions for the nuclear plant of course come from the fuel mining and milling.

Nicholson, Biegler & Brook (2011) “How carbon pricing changes the relative competitiveness of low-carbon baseload generating technologies” Energy doi: 10.1016/j.energy.2010.10.039

It is now simple to work out the greenhouse gas emissions that would result from generating 900,000 GWh of electricity from coal (824 million tCO2-e), gas (423 million tCO2-e) and nuclear (18 million tCO2-e). That is, the uranium from the expanded Olympic Dam, when fed to nuclear power plants, would generate 3.7 times the total current electricity demand of Australia, and avoid 405 to 806 million tCO2-e from being emitted to the atmosphere by displacing gas and coal. In this context, the additional 4.7 million tCO2-e generated by the mine expansion is little more than rounding error!

Indeed, Australia’s total emissions (all sectors) in 2010 were 560 million tCO2-e, and South Australia’s at up to 31 million tCO2-e. Therefore, the uranium from the expanded mine would be sufficient to offset all of Australia’s current domestic greenhouse gas emissions, or between 13 to 26 times South Australia’s total emissions. Note that these are not just emissions from stationary energy generation, but also from transport, industry, agriculture and so on.

By any reasonable measure that is not a “huge carbon black hole” – it is a massive win for global greenhouse gas mitigation.

The news gets even better. As we have explained in previous SACOME articles, current nuclear technology extracts less than 1 per cent of the energy from mined uranium. With the future large-scale deployment of next-generation technologies like the Integral Fast Reactor, which is able to repeatedly recycle the used nuclear fuel and use all of the depleted uranium, we will unlock the potential to extract 150 times more heat and electricity from uranium than we currently do.

If you crunch these numbers, you find that the 19,000 tUO2 per annum production from the Olympic Dam expansion would eventually yield 130 million GWh of zero-carbon electricity, and so avoid up to 120 billion tCO2-e, which is four times the total current global emissions from fossil fuels. All of this from one (albeit large) expansion of one uranium mine in one country.

It’s easy to tell horror stories about uranium if you rob it of the context of its role in global energy supply. We deserve much better than such rhetorical chicanery. Clearly, it’s time that environmentalists got sensible about uranium mining, nuclear power and carbon emissions.

Barry Brook and Ben Heard

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For comments on this post, we encourage you to use the BNC Discussion Forum. The link for this post is:

http://bravenewclimate.proboards.com/index.cgi?action=display&board=bncblogposts&thread=82

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4 Comments

  1. Why aren’t the Greens engaging with this analysis? Is there any evidence of a serious debate on nuclear power in the party room?

    MODERATOR
    Hi Geoff – thanks for your comment. We have just implemented a BNC Discussion Forum which is now the place to discuss anything on BNC and to create your own topics to be discussed with the community. The question you pose here would be a good topic to develop on the Forum. To go directly to the BNC Forum click on the Forum tab, next to Home, at the top of the BNC page. See you there :)

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  2. I have been regularly following the Discussion Forum since its inception. Given the bewildering number of topic headings, I attempt to keep abreast of things by going directly to the “New” heading. My conclusion is that there isn’t a great amount that’s new and that the majority of BNC’s erstwhile regular correspondents haven’t made the crossover to the Forum. Could the Moderator check on the average numbers of comments before and after the policy change to check whether my conclusion is false? I was provoked into this comment by finding nothing relating to the above (most recent) post in the “new” section on the Forum.

    I might add that I do follow the Energy from Thorium Discussion forum and am largely happy with its layout. I think a problem with the BNC Forum (if it has one) may be due to the fact that a potential contributor will be likely to struggle to opt for the best subject heading to comment under, given the number of potentially relevant possibilities, and may therefore not comment at all.

    MODERATOR
    Hi Douglas – sorry you are having trouble commenting on the Forum.
    You are probably most interested in commenting on any BNC blog posts which will continue to appear on the usual BNC blog site. Instead of clicking on the “new topics” button, click on the “home” button http://bravenewclimate.proboards.com/index.cgi
    which will take you to the main page and the first heading you see will be “BNC Blog Post Comments”.http://bravenewclimate.proboards.com/index.cgi?board=bncblogposts

    If you click on this you will be taken to a list of the latest BNC posts including “Carbon offsetting of uranium mines” now click on this heading and it will open the comments thread for that post. This post has had 347 views so far and 19 comments. You can check for yourself how many views and comments each post has received in the columns beside each post title.

    post.http://bravenewclimate.proboards.com/index.cgi?board=bncblogposts&action=display&thread=82

    The “home” page also lists topic subjects under broad categories such as Climate Science, Nuclear Energy, Renewable Energy etc which break down into more specific sub-boards e.g. on the Nuclear Energy board some sub-boards are Nuclear Waste, Radiation, Safety etc. Each main board has a General Discussion board which may be used like an Open Thread for that main topic. You can choose to start a new discussion yourself or join in one already running.

    Do have a play around with the category boards on the “home” page to familiarise yourself with what is being discussed.

    However, as I said, if you just want to comment on any BNC post you only ever have to click on the “BNC Blog Post Comments” board on the “home” page.

    The “new topics” button only takes you to a list of the latest comments on any topic and switches between topics, (the newest or older) depending on who has last commented on which topic thread and probably not all that useful for your purposes.However, a quick scan down the page will reveal the most commented on “hot” topics as a flaming folder appears on the right hand side of the post title. You can of course, click on that burning folder to take you directly to that post. The “hottest” topics are often the BNC current blog posts.

    Be aware that this is a work in progress and Barry is open to changes which may improve the Forum. I will have look at the “Energy from Thorium” discussion forum to see how they go about things and I will also have a talk with Barry about your concerns.

    Please hang in there and don’t desert us just yet:) Hope this helps.

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  3. Pingback: Is the Olympic Dam mine a special case? « BraveNewClimate

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