Few people
fully appreciate the uniqueness of nuclear fission as an energy source, and why
this uniqueness makes all the difference in establishing an energy policy. Oh sure, many people have been scared
into believing that nuclear power is uniquely dangerous, although we’ve
long-since shown that nuclear power stations are safer than any of their
competitors. For its workers and
for the public. Literally. Decades of safe, reliable operation are
available, plus a billion dollars of testing and analysis . But that’s another post.
The
uniqueness of nuclear power is that it outperforms its competitors by orders of
magnitude. We’re used to choosing among options that vary a few percent, or
maybe a factor of two or four. A nuclear fission fuel is more than seven
orders of magnitude more efficient than any non-nuclear process. That’s seven multiples of ten, or ten million times more
efficient. That number cannot be changed
significantly by more research. It involves the fundamental difference between
the binding energies of atoms and of molecules. (In real examples, the
difference is usually several tens of millions. I usually use 50 million as the ratio between nuclear and
non-nuclear fuels.)
Let’s look at
how orders-of-magnitude differences play out in the work-a-day world.
For example,
commercial aircraft travel about 500 miles per hour (mph). That’s an order of magnitude faster
than cars or trains, whose cruising speed is about 50 mph. And nearly two orders of magnitude
faster than bicycles at 5-10 mph.
An airline might consider buying aircraft that are, say 20% (100mph)
faster or slower. But not a whole
factor of ten. Someone taking a business trip to Los Angeles from New York
would have to have a good reason not to fly. And it’s is even unlikelier s/he’d choose the bike.
In the energy
field, this means that any non-nuclear fuel—coal, ethanol, corn-stalks,
algae—requires fifty million times as much material to be gathered up,
transported, processed, and ultimately to be disposed of, than if nuclear fuel
were used to make the same amount of electricity. (Wind or sunshine are even more dilute, and also unreliable.
)
Again, to
understand what this means, we have to get actual numbers. Let’s look at just part of the
energy problem, replacing the coal used to make electricity in America. Coal is mostly all carbon, and therefore is the cheapest,
most efficient way to ship carbon.
Yet it still requires half the capacity of our entire national freight
rail system to handle it. How will
we transport the same amount of carbon in the form of sugar-cane or
switch-grass? Paul Willems (“The
Biofuels Landscape Through the Lens
of Industrial Chemistry,” Science 325, 707, 7 Aug 2009) writes: “Biomass is a bulky solid
with relatively high water content. The range over which it can be economically
transported to a manufacturing facility is on the order of 40 to 80 km.”
Do we really
plan to set up biomass processing plants every 25-50 miles across America’s
agricultural heartland? It seems to me this is a show-stopper. If we can’t answer this mundane
question, then we shouldn’t be making grandiose plans for a 500 million tons
per year biomass program. We could
support quite a crowd of researchers for decades that way, but if it’s never
going to lead to a practical energy program, we should drop it. Or if it’s to be justified as a
biological research program, then it should be so designed, and not hidden
under a false promise.



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