I absolutely disagree that the world is going to run out of nuclear resources in the lifetime of anyone now living.
Then again, I've spent lots of time reading about advanced fuel cycles. I happen to know the difference between CORAIL and MOX-UE, not one of which was mentioned here.
Neither was the Radkowsky fuel cycle mentioned. In fact, the presentation is at a rather low level. The remarks on tritium breeding are roughly correct, but I have never been on this website hawking fusion.
Looking at the current fuel cycle and pulling out a little excel spreadsheet and making a cute graph based on current enrichments and burn-ups doesn't cut it, not even remotely.
Further I've actually read all 17 papers on amidoxime resins which are so blithely dismissed in this (poorly edited) "presentation," with its website links.
In fact, I have most of them on my hard drive. For instance from
Ind. Eng. Chem. Res. 2000, 39, 2910-2915, which could have been referenced in this presentation but somehow wasn't - it took me about 2 minutes to find it and download it - we can read:
The amount of uranium adsorbed in the submerged mode of operation at an ocean site for 20 days of contact is shown in Figure 8a as a function of the weight ratio of AN/MAA or AN/HEMA in the monomer mixture. The AO fibers prepared by cografting MAA with AN at a weight ratio of AN/MAA of 60/40 and subsequent amidoximation exhibited a maximum value of 0.90 g of U/kg. However, the submerged mode of operation includes some uncertainity because the temperature and velocity of the seawater vary according to weather and seawater conditions. The uranium adsorptivity of the fibrous adsorbents was ascertained in the flow-through mode in a laboratory, where the temperature and flow rate of seawater were maintained at prescribed values. A similar dependence of the amount of uranium adsorbed on x/y was observed as shown in Figure 8b.
Note that very little has been done to
optimize this approach, but it is relatively easy to see that with a breeding ratio of close to one - and I'm leaving fast cycles out of this arbitrarily - a reactor with a reasonable neutron efficiency and a breeding ratio near one can operate for decades on the annual output of 500,000 tons of resin -
assuming there is no other source of uranium. The thermodynamic penalty is small, since, ironically enough, the energy driver for the separation - which produces essentially a low grade uranium ore - is solar energy - the ocean currents.
A breeding ratio of 1.00 is easily approachable
with existing types of thermal reactors particularly those types using thorium - an element in the periodic table which apparently the "presenter" never heard about. Currently most of the world's thorium is
dumped as a side product from monzanite ore processing for lanthanides.
India - which is rich in thorium - is actively developing a thorium fuel cycle and in fact the very first nuclear reactor in the United States, the Shippingport reactor operated on thorium for its last fuel cycle. Thus the technology for thermal breeding is about 40 years old, though you'd never hear it from our "calculate the amount of U-235 available from mines" set.
If one can operate thermal reactors at such a breeding ratio, it is really, really, really, really silly to build elaborate liquid metal fast breeders - not that they won't work. The anti-nukes, with their rather
childish insistence that nuclear technology unlike what they
say their pet solar systems - which have yet to produce a single exajoule - is locked in the 1970s. Actually the advances in material science since say, 1975, have been enormous.
The main reason that advanced fuel cycles were
not developed in the 1970's was 1) uranium proved to be far more common than ever believed and 2) nuclear power was constrained in its growth rate by technical (but probably inevitable) growing pains and thus less uranium was needed than expected and 3) artificial and fanciful fears of plutonium based on silly war scenarios produced by the likes of Amory Lovins, internationally famous Walmart marketing genius.
Japan has built a reprocessing facility recently and plans to expand it, in spite of the fact that recent earthquake that killed everyone in the country. France has examined proposals for its plutonium inventories and has decided that about 600 MT would keep the fires burning for quite a long time.
Some fast spectrum reactors will probably prove necessary - should humanity survive climate change (and it won't without nuclear power) - if only to minimize the accumulation of higher actinides like curium, although curium-244, curium-242 and plutonium-238 all offer the potential of an extra "kick" per kg because of their high thermal output from alpha decay. A few grams of Cm-242 (half life about 162 days) could provide about the average power output of a typical human being on this planet, about 2000 watts. Regrettably only a few hundred kilograms of this isotope could ever accumulate because of radioequilibrium, but in fact one could extend actinide resources by a few percent by this simple, currently unused approach (except on spacecraft like Cassini and Voyager).
Uranium is about as common as tin, and tin is not a particularly rare element. The energy density of uranium is enormous. One kg of uranium, fully fissioned represents about 600,000 gallons of gasoline. The fact is that the
world ran all of its nuclear power plants
on inventory through the 1990's, making uranium an almost worthless commodity as a mined fuel.
As it happens, only a tiny fraction of the available energy in uranium is extracted. If you haven't read a single nuclear technology article since 1968, you might believe that these resources cannot be recovered, but on the other hand if you keep up with modern literature, you quickly recognize that only a tiny subset of approaches to breeding have ever been
touched. There are, for instance, nearly an infinite set of molten salt reactors, but none have been commercially developed. Why? Because the existing pressurized water reactor was so damn good, they weren't
needed.
As it happens, fuel burn ups, particularly with thorium - which has mystically stayed out of this presentation for the reason that the point of the presentation seems to be yet another paean that we're all going to die - is
missing. Reactor burn-ups have risen from less than 20,000 MW-day/MTHM in the 1960's and 1970's to well over double that figure, but there is no intrinsic reason to expect that higher burn-ups are not feasible
in one fuel cycle. Recently reactors have been approaching 2 years without refueling and records are being rather regularly broken, accounting for the huge rise in capacity utilization. Burn-ups of 45,000 MW-day/MTHM are now pretty routine from my understanding.
Nuclear power can do enormous things. Consider that while the anti-nukes were
bitching about nuclear power and claiming with a rather curious inattention to the tragedy of dangerous fossil fuels; dangerous fossil fuel waste, dangerous fossil fuel terrorism, dangerous fossil fuel depletion, dangerous fossil fuel war, etc, etc, the output of nuclear power went to nearly 30 exajoules of primary energy, nearly quadrupling since 1980, without building all that many new reactors. Imagine if people had been remotely
sensible and literate about the subject. We might not be in this fix.
In the same period that nuclear was quadrupling on an exajoule scale, with all kinds of cheering, the non-hydro renewable energy has remained below 2 exajoules as electricity, where it has been for nearly 50 years.
Will realizing nuclear's potential be
easy and cheap? No, of course not. However it will be
easier and
cheaper than all other options, because there really are no
better options. There never have been and there never
will be probably.
In fact, nuclear power is the only new ten exajoule scale form of primary energy developed in the last 50 years. If it doesn't work, nothing will work.
The one size fits all "peak" fantasy may apply to oil and coal and gas and in fact
should apply to them because they are so dangerous but frankly, I find it reasonable to consider that nuclear resources may, in fact, be quite nearly renewable, given that most of the earth's internal heat derives from uranium thorium and that nuclear materials are continuously recycled from earth's mantle. As to how "renewable" they are, uranium resources may be better in fact than things like biofuels, which are hardly really renewable given the fact that they mine soil and water and depend on industrially fixed nitrogen to work. Certainly the external cost of nuclear is lower than biofuels and the return on both energy invested and money invested is much, much, much, much larger.
It doesn't matter, though, whether nuclear energy can do
everything. I think it can - at least in a world with a reduced population - and I find all the tortured representations like this
silly presentation rather amusing. The point is that we should test the limits of what nuclear can do by investing in it heavily. It gives the biggest bang for the buck, by far.
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