Wednesday, May 31, 2006

What Price: Nuclear Power?

What price will we pay for nuclear power? The price of uranium has now risen beyond $40 per pound after spending many years at around a quarter of that. One is reminded of the recent surge in oil prices, and it does enmesh into a prognosis that energy is going to become increasingly expensive, and probably rare. Although many other metals, notably copper, have also experienced a huge rise in their cost on the open market mainly from a massive demand for them in China, uranium has attracted interest from people who previously had paid no attention to it or indeed to nuclear power at all. This is a boon to the industry, but any benefits might prove purely short term gains, as speculators, who may well leave as quickly as they came, are thought to have caused some of the escalation in the price of uranium. There are now around 300 different companies who supply uranium, and it is generally believed that the world will need increasing quantities of it as a "primary" source (i.e. as dug out of the ground) in order to decrease its reliance on "secondary" uranium (i.e. as recovered from used nuclear fuel rods by reprocessing, or as fabricated from dismantled nuclear weapons). I was recently told by someone from a well known British nuclear energy company that the U.K. had sufficient uranium reserves in the form of nuclear warheads to provide the nation's 20% share of its electricity production for 100 years. That, I presume would mean using fast breeder reactors. In any event, the rising demand for nuclear power in China, Russia, India, the U.S. and the U.K. will necessitate the increased mining of uranium, although India is fortunate in having substantial reserves of thorium (232) which can be converted into the fissile nuclear fuel, uranium-233 by irradiation with neutrons, so this country may be less dependent on the flexings of the world uranium market.
However, as with "Peak Oil" there are few indicators that more uranium is in the pipeline. In both the years 2004 and 2005, world production of uranium was around 40,000 tonnes, and 2006 looks about the same. It is interesting to compare this figure with the approximately 75,000 tonnes of uranium that is actually "burnt" by the global nuclear powered electricity industry, and so nearly half of it must come from "secondary" sources, according to simple arithmetic, as has been the case for the past twenty years. There is considerable disagreement as to exactly how much uranium exists on Earth. It is true that along with other metals such as tin, tungsten and molybdenum, uranium is not geologically rare. However, it is the quality of the ore that is at issue, and there are only available reserves of high-grade uranium ore estimated at around 3-4 million tonnes, which is just sufficient to empower the world's static nuclear power industry for about 50 years. Any envisaged expansion must secure more uranium, or the current proposal, emphatically spoken of by the U.K. Prime Minister, Tony Blair, is at most a hugely costly short-term measure, and probably best avoided. Fast breeder reactors were heralded as "the future" in the 1970's, but little development of this technology has in fact materialised since then, mainly due to the perceived risks of handling plutonium as the reactor fuel, and the necessity to use liquid sodium metal or the liquid alloy of sodium and potassium, which explodes on contact with water, as the "coolant" (heat exchange medium). Neither ordinary (light, H2O) water nor heavy water (deuterium oxide, D2O) can be used to cool a fast breeder reactor since these materials moderate (slow down) the fast neutrons that are most effective in "breeding" uranium-238 into plutonium-239 as the fissile nuclear fuel.
Ultimately, the stage is realised at which more energy must be expended in extracting the uranium fuel than is actually recovered by its use in a nuclear power plant - a clearly self-defeating exercise, particularly if it is true that we need to employ nuclear in order to reduce our carbon emissions; obviously we would in this case be producing more CO2 by using nuclear than without it. The issue of security of supply remains a thorny matter, as Europe (which includes us in the U.K.) buys all its uranium from Russia, who get much of that from Kazakhstan, and one can only speculate upon the political situation that might prevail in 10, 20 or more years in this rapidly changing world, upon which we witness the shift in economic and political clout, which seems mainly to follow available resources and their implications. Perhaps the current "suppliers" of the various fuels we all depend upon (oil, gas, uranium and coal) will find it more expedient to simply hang on to them for their own use, rather than selling them on for cash.

4 comments:

Kirk Sorensen said...

You've put your finger right on the problem--there's not enough uranium to sustain our current nuclear power plants (which are wastefully burning through the scarce U-235) yet the prospect of fast breeder reactors should give us great pause. They are sources of excellent quality (weapons-grade) plutonium, and they have dubious safety features (to be kind).

As you identified, thorium is another way. It can be "burned" in a thermal-neutron spectrum, and it does not produce attractive material for nuclear weapons (U-233 has many disadvantages for weapons, which is why no operational nuclear weapon has ever used it). But converting thorium to energy in a thermal-neutron-spectrum requires almost constant reprocessing. How can this be done? By using a fluid-fuel form. In the 1950s, they examined uranyl sulfate dissovled in light or heavy water, liquid-fluoride salts of uranium and thorium, and uranium metal dissolved in bismuth metal--all as thermal-spectrum thorium reactors.

They ultimately concluded that the liquid-fluoride reactor offered the best chance for success--learn more at:

http://thoriumenergy.blogspot.com/

energybalance said...

Hi,

very nice to hear from you! You probably know better than me, but what exactly is the total world reserve of thorium? I have heard that it is present in the Earth at about 4 times the quantity of uranium - according to geological estimates, and mostly in India.

But again it must be a finite resource, like uranium. The political future (the balance of power) must also depend on which countries of the world have the resource, and it would be interesting if the British Empire were to become dependent on India, considering the past!

Do you really think that "thorium" is "limitless"; i.e. sufficient to produce enough "fuel" to substitute for the fantastic levels of liquid petroleum fuel consumed by the world, especially in the U.S., hence I suspect much of the invading activity in that particular geological belt of the Earth just now (Iraq, Iran, Afghanistan), and whatever that may bring?

In my opinion, it is the problem of providing fuel for vehicles that is manifest. I was in Prague last week, and once again profoundly impressed by their public transport system. Access to trams, metro, and buses that run outside the city centre for a week for just about 15 dollors (U.S.). So, yes, I am coming round to the idea that we could live in smaller communities powered by a tram system. No more 4 by 4's (S.U.V.'s I believe you call them in the "States") to take the kids to school! The entire set of roads around here are gridlocked between about 8.00 and 8.30. It is ridiculous, and in the South East of England there are more and more "developments" all the time, restricted only bu the local councils. Does no-one have any sense?!

Back to thorium, I presume too that the viability of the material depends on the quality of the ore that can be mined? Otherwise we are in trouble over the amount of CO2 emitted through the entire process of milling, extraction, fabrication into nuclear fuel rods etc. etc.

I would be interested too in reading any views you have about bio-diesel, etc. I think it is the aspect of transportation that bedevills us, and we could probably live O.K. in "the west" on coal for the most part, but we thence need to live differently, and I can envisage a "return" to the kind of west-country live documented by Thomas Hardy, which in fact is not much different from my childhood in Gloucestershire! Indeed, we used more energy per capita in 1900 than we do now in the U.K., which doesn't explain the global rise in CO2 levels since, but it is not just us, and the global population has expanded vastly (by about 4 billion) since then, etc. etc.

These are just my thoughts, and thanks for allerting me to your "blog" which I have just looked at and will read avidly! If thorium is the solution, or any other fuel for that matter, fine. Of course, 80% of our "energy" in the U.K. is provided not from electricity but from natural gas mainly, which we are now net importers of, and from coal - and 26% of that total energy used is for transporation, of course provided from oil!

Without sensible elected leadership on these matters, the world is heading for a really big mess, and I hope we manage to contravene that!

Hydrogen has to come from somewhere, and is now made from natural gas (methane), which as you say could be used for "coal liquifaction" although the technology on a large scale is untested. Of course the Germans managed to produce synthetic petroleum when their supplies were "cut-off" during WWII, again from coal as the carbon source, plus water. That I guess could be done again, but what about the CO2 emissions? There seems to be two issues at odds with one another: greenhouse gases and fuel!

Kind regards,

Chris Rhodes.

Kirk Sorensen said...

Hello Chris,

Wonderful blog you have here! When I posted before I had not read much of it yet, but I have been going back through older posts (starting at the beginning) and it's clear that you've been doing a lot of thinking about this, and are kind enough to share with the rest of us many of your thoughts. Thank you!

As far as the exact amount of thorium in the world--that's anyone's guess. Thorium has never been sought to the degree that uranium has been sought, although it's roughly 4 times more abundant. Most thorium deposits we know about (such as the beach sands in India, Brazil, and Florida) we know about because they're right there on the surface.

Thorium has not been sought to any great degree because it is not inherently fissile, and to convert it to energy, we must have a neutronically efficient reactor capable of constant reprocessing. Since we've been obsessed with building solid-core reactors for the last 50 years, it's not surprising that interest in thorium has been slight. They thought uranium was rare until they started looking for it.

At any rate, yes I do think thorium could displace nearly all other forms of energy, for it is extraordinarily energy-dense and through the liquid-fluoride reactor it can be safely converted into heat energy. That heat energy can then be converted into electricity, hydrogen, or a host of other useful products.

I recently did some calculations on the amount of thorium required to displace all other forms of energy (assuming the thorium was "burned" in a liquid-fluoride reactor). I calculated how many quads of energy coal, oil, natural gas, and uranium produced in 1998 (376 quads) and how much thorium would be needed to produce that energy (5000 metric tonnes). Consider that in 1998 there was 65,000 metric tonnes of uranium used to produce only 24 quads of energy, and you get an idea just how energy-dense thorium can be in a liquid fluoride reactor. Let's assume world energy use went up to 1000 quads (tripled). About 15,000 MT of thorium, or the output of three typical thorium mines worldwide. That's a pretty attractive scenario.

In fact, a study done by ORNL in the 1970s showed that a single mine in Idaho could produce 4500 MT of thorium per year, which would roughly supply the entire world's energy. No nation will need to fight over thorium, for they either probably have enough in their own borders, or it will be so inexpensive they can buy it readily.

In fact, thorium is so "worthless" right now that the US gov't just buried their entire stockpile of thorium (3216 MT) in the Nevada desert...what a waste!

energybalance said...

Hi Kirk,

thankyou very much for your kind words! My plan is to run the blog for a year and see how it goes. I am pleased that it "is" being read and a friend of mine who works in a university in the U.S. has recommended it to his students. I used to be a university Professor in Physical Chemistry, but ducked out of that under the wave of chemistry courses and departments being closed, and my job as a research professor effectively being cancelled in terms of its nature. So, rather than stay on as a lab technician (yes, really), I decided to set up my own consulting business in which I do various things but mostly advise industry on how to reduce their pollution levels into the environment.

I have just written a novel about what has happened to the U.K. "university" system, which I am working on the marketing of just now. You don't know a literary agent, do you?!

What is your particular line of business?

I looked on Wikipedia and it seems there are "known" reserves of throium to the extent of 1.2 million tonnes. Does that sound about right. In fact that figure is lower than I had thought, since I recall there is 4 times as much of it as there is uranium, but that doesn't square with the "known" reserves of uranium at 4.5 million tonnes? As you say, if there has been little serious exploration for thorium as there as for uranium, there may well be far more resreves of it, and then it does begin to look like the "light at the end of the tunnel".

Yes, as you say, I have been doing quite a bit of thinking about the "road to hell" that humankind seems bent upon, and I hope that with thorium or what else, we can pull ourselves out of a nose dive! Clean electric power (thorium?), energy efficiency and a more localised approach, perhaps via a highly efficient "Prague type" tram and metro system might be what we need to obviate the inevitable downfall of oil dependency.

I will read the web site that you recommend and maybe write a posting about "thorium", as you have convinced me that there may well be a solution found here!

All best wishes,

Chris.