What the heck is Thorium?

Quick!  When I say uranium, what do you think of?  If I say plutonium?  Being the psychic that I am, I know that images of yellow radiation triangles are flashing across your mind with flashing lights and alarms going off.  Your mind starts flashing danger warnings to you as visions of mushroom clouds start dancing in the back of your head.  Am I close?  These elements are perceived now as two of the most dangerous elements on Earth, and because of this, it is no mystery as to why people are so adverse to nuclear power.  The raw materials themselves which the industry has been built around are the most dangerous things known to man kind!

This isn't really true as you could probably tell from the loud rolling of my eyes seen between the lines of my comments.  Why would people be lead to believe such statements?  Well, the truth is that the industry did it to itself.  You see, the nuclear power industry has always had kind of a free ride as far as development goes.  This stems from the world governments having such a large interest in the power of the atom:  not in nuclear power per say, but in nuclear weapons.  The research needed to be done to learn the fundamentals of nuclear fission reactions was all geared toward weapons research.  Much of the nuclear research done to this day is paid for by the department of defense.  It is a horrible history and a fact that the industry will be haunted by for a long time, but weapons research is why we have nuclear power.

Because of this, the funds geared toward nuclear research has been spent learning about the materials suitable for weapons production.  As you might guess, it is uranium-235, uranium-238, and plutonium-239 that got a lot of the attention.  Labs like the one in Los Alamos, New Mexico characterized the fission behaviors of these elements really really well.  It would have been illogical for the nuclear industry to ignore the data being handed to them on the performance of such fuels.  Thus, the private industry was enticed into designing the civilian reactors around what we knew:  U-235, U-238, and Pu-239.  The nuclear power industry became a parasite of the weapons program since that is where the funding was going.  At this point, the industry was just asking for proliferation issues, but I will get to that later.

Currently, the nuclear power industry faces many challenges which all trace their beginnings back to the weapons legacy of the system.  Fortunately for the industry, it turns out that uranium is not the only option for usable fuel cycles in the reactors.  In fact, uranium isn't even the best type of fuel for commercial power production!  This might be the bit of good news that the nuclear power industry needs to get back over the hump of public skepticism.

It is not a magic bullet to the issues facing nuclear power, but the thorium fuel cycle is the way the the industry will separate itself from its weapons legacy.  You see, the weapons program that the government was funding did not care what materials were optimum for power production, but only those that were optimal for building the "big stick" that the country was founding its defense strategies upon.  Now though, the ball is in a different court.  We aren't so much facing a nuclear holocaust anymore so much as the world becoming a giant human oven.  Nuclear power is seen as the forerunner for mitigating the human effects on global warming.  What does this mean?  Well, I hope that it means that funding will be sent back toward developing a nuclear fuel cycle optimized for power production, but I guess only time will tell.

So what is better about thorium?  That is probably the question that is on your mind at this point, or at least it is now since I just made it so.  Many of you probably have never even heard of thorium or the thorium fuel cycle which I only know because I had never heard of it before reaching graduate level classes in nuclear engineering.  As it turns out, it is a pretty well kept secret and it should definitely not be.  If you go back and dust of that old periodic table that you have from the chemistry class you took in high school, you can find thorium two spaces to the left of uranium in that infamous f-block of the table.  Yes, there it is, a naturally occurring substance that nobody ever concerned themselves with.  This is the element that could be the solution of the world's energy problems for thousands and thousands of years.

The biggest selling point of designing reactors for thorium fuel...the abundance of it here on Earth!  In fact, thorium is between 3 and 4 times more common in nature than uranium.  If you have been following me for a while, you have heard my rantings on how much uranium we have in reserve.  Thorium being this much more abundant means that solar and wind power would not have to be developed for use any time soon.  In fact, there is enough thorium now to have powered mankind at current demand since the first man was born out of a monkey.  Not that I believe this is how mankind came about, but you get my point.  We have a lot of power available with a thorium fuel cycle.  Of course, we have enough uranium to power us into the quite distant future as well, so why the heck would we want to spend so much on research to redevelop the technology?

There are many many reasons that thorium is a much better fuel cycle and I hope to address more of them in future posts in more detail, but I am going to hit a few of the basics here.  First of all, like I stated above, the thorium cycle will take us away from the ties the industry has to nuclear weapons.  This is not only true by taking uranium out of the picture, but also by putting up major barriers to nuclear proliferation.  Unlike uranium, thorium contains no natural isotopes which are fissile.  By this, I mean that unlike uranium, thorium will not undergo nuclear fission in its natural state.  This by itself means that thorium cannot be processed or used to create a weapon.

Thorium is found completely in nature as thorium-232.  In a reactor, very very small amounts of material that can be used to create a weapon are generated.  Beyond this, many of the fission daughter products which result from nuclear fission in the reactor have very short half lives.  This means, in the case of thorium, that what comes out of the reactor is a very strong gamma-ray emitter.  This provides two types of protections as far as nuclear proliferation goes.  It makes the waste very easy to detect if it were ever to be stolen, and it makes the waste very hard to work with.  In order to create a weapon from what comes out of the thorium cycle, one would need special facilities to do it as getting near the waste to process would kill them.  All management of the spent fuel is done remotely, including the reprocessing of it for reusing the fuel.  Take away message, steeling the fuel and creating weapons from the spent fuel is pretty much impossible eliminating the fears we have of this with the uranium fuel cycle.

Another major benefit is the much shorter lifespan of the waste from the thorium fuel cycle.  Like I said above, the half lives of the wastes from the thorium fuel cycle are much much shorter.  Instead of looking at half lives on the order of tens of thousands of years, we are looking now at half lives on the order of less than 100 years.  The waste storage issues are made much simpler with the thorium cycle, which a much needed boost to nuclear power.

There are many more advantages to the thorium cycle, but I will defer discussing them to a later time because I feel that I have hit you over the head with enough technical information for one day.  If you are really curious though and want a technical explanation of the thorium cycle, check out this report.  It is long and technical, but it is very informative.  I wouldn't read it if I were you though...It is spring time and you should be thinking about going outside at this point instead.