Comments on: Rethinking nuclear power.

By: Luke Weston

Luke Weston — Sat, 03 Oct 2009 12:00:49 +0000

I apologise regarding comments not getting posted.

Sometimes I get really busy and forget to check the software’s log of comments that it won’t post pending manual approval by the blog moderator.

By: Joffan

Joffan — Tue, 04 Aug 2009 22:40:00 +0000

Given that the biggest uranium mine is actually a copper mine, Olympic Dam, it seems pointless to speculate about the need to close down urnaium mines when they are often getting the uranium almost as a by-product. Where uranium is mined in its own right, the footprint per unit energy is relatively low, and could be smaller yet.

And the fact that the energy in uranium is nuclear, not chemical, means that in-situ extraction is feasible, with vastly less of the normal envirnomental disruption compared to mechanical ore extraction generally.

SO I wouldn’t hasten to close uranium mines. None of which takes away from the potential energy you describe, that we have locked up in already-extracted uranium, and indeed already-extracted thorium.

Note also that CANDU reactors run on unenriched uranium using heavy-water moderation.

By: uvdiv

uvdiv — Sun, 26 Jul 2009 10:25:33 +0000

Oh well. I’ve posted my comment as a blog post.

http://uvdiv.blogspot.com/2009/07/ive-thought-about-this-and-it-isnt.html

In short: you should consider the impact of the “starting material” requirements of fissile material.

By: uvdiv

uvdiv — Sun, 26 Jul 2009 10:22:38 +0000

Yes it is: it discards my comment – gives me a page saying “discarded”. But I can post these comments. Which means something about my comment is making it unpublishable.

By: uvdiv

uvdiv — Sun, 26 Jul 2009 10:21:36 +0000

Is the comment system broken?

By: Charles Barton

Charles Barton — Tue, 12 May 2009 11:29:05 +0000

Luke, There would be very little difference between the cost of thorium and uranium. A lot of thorium exists in easily accessible forms, so the cost of thorium would competitive with uranium. The LFTR has a big cost advantage with its ability to process core fuel and blanket salts. Fuel has to be extracted from the IFR and processed in a separate production facility. This adds to cost. The LFTR is safer than the IFR. The LFTR would most likely be cheaper to build and set up. A Liquid Chloride Fast Reactor would take some time to develop, but would erase most of the LFTR advantages while operating on the Uranium Fuel cycle. The LCFR is less proliferation resistant than the LFTR, otherwise they are quite similar. The LCFR would have a higher breeding ratio. The LFTR would have a clear economic advantage over the IFR, The LCFR might have some economic advantage over the LFTR, but by the time LCFRs were built the LFTR might have a leg up because it had a large installed base.

By: Marcel F. Williams

Marcel F. Williams — Sun, 03 May 2009 18:52:20 +0000

There’s an alternate way to end terrestrial uranium mining and that is to utilize marine uranium.

The world’s oceans contain more than 4 billion tonnes of uranium in seawater. That’s enough to power our entire planet (electricity, synfuels, and industrial chemicals) for more than 3600 years or over 5000 years if spent fuel is re-utilized. So terrestrial nuclear mining could also be ended by using marine uranium in current the current generation of nuclear power plants without any new breeding technologies.

http://newpapyrusmagazine.blogspot.com/2008/10/fueling-our-nuclear-future.html

By: Robert Hargraves

Robert Hargraves — Sun, 03 May 2009 18:39:45 +0000

Luke,

Your article caught my eye because the title is like that of my Dartmouth ILEAD course, Energy Policy and Environmental Choices: Rethinking Nuclear Power. Your readers might enjoy paging through some of the hundreds of PowerPoint graphics and web references in the course, posted at http://rethinkingnuclearpower.googlepages.com.

Also, I’m a proponent of the LFTR. I don’t think the “already mined” argument for using depleted uranium is strong since very little mining will be required for thorium, and it can even be extracted from existing mine tailings. The LFTR does have the advantage that there will be considerably less long-lived radioactive actinide waste in the LFTR waste stream than, say, the IFR, because six fewer neutron absorptions are required in using Th-232. I think the LFTR thermal neutron flux provides better control ability than in fast neutron reactors. There is an illustrative presentation of the LFTR at http://rethinkingnuclearpower.googlepages.com/aimhigh and more technical details at http://energyfromthorium.com.