Knowledge is
power.
(Francis
Bacon)
Things alter
for the worse spontaneously, if they be not altered for the better designedly.
(Francis
Bacon)
The scientific
and technological achievements of humans have been remarkable, and we are
currently passing through a technologically explosive phase. Naturally, the
mood is upbeat and there is no shortage of people who are confident that we can
overcome the ecological footprint problem I mentioned in Part 60. Nanotechnology
may provide some critical breakthroughs. Progress in the burgeoning field of
artificial smart structures (Wadhawan 2007) may well
lead to the emergence of cyborgs (creatures who are part human part machine)
and Robo sapiens (robots so advanced that they would leave their creators,
i.e. humans, far behind in practically all respects). Intelligent robots,
cyborgs, and genetically engineered humans are expected to be not only less
delicate when it comes to survival in harsher conditions, they will actually
be far more efficient consumers of energy, thus having a lower
ecological footprint.
Francis Bacon played a major role in establishing what we
now call the scientific method. He was also
the original proponent of the imperial approach, namely the aggressive
use of science and technology for conquering Nature and establishing the
supremacy of humans in all things that matter.
Michio Kaku is a modern-day advocate of the imperial
approach. In his book 'Visions: How Science Will Revolutionize the 21st Century' he
visualizes a 'phase transition' for humanity from passive observer to an active
choreographer of Nature. Genetic modification 'will ultimately give us the
nearly God-like ability to manipulate life almost at will'. Concepts like 'gene
doping' and 'synthetic life' are already being explored by biochemists.
According to Gibbs (2004): 'Biologists
are crafting libraries of interchangeable DNA parts and assembling them inside
microbes to create programmable living machines ... Evolution is a wellspring
of creativity ... But there is still plenty of room for improvement.'
How will the
energy needs be met for this scenario? Fossil fuels cannot last forever.
Conventional oil and gas will be the first to go. Coal can last a little
longer. Unconventional oils (oil shales, heavy oils, tar sands) can stretch the
economically feasible fossil-fuels era by a century. Unconventional gas sources
(methane in coal-beds and in other deposits such as the tight reservoirs and
the high-pressure aquifers, as also the methane in hydrates) can also be
exploited for some time, provided the necessary technology becomes available in
an economically viable manner. The gas hydrates comprising of huge amounts of
combustible carbon offer a potentially large source of energy, although expert
opinion is divided about their economical and ecologically clean exploitation
(Smil 2003).
A new dominant
energy source other than fossil fuels must emerge, and according to the
Imperial Man it must be nuclear energy.
Nuclear
fission is already being exploited for power production on a commercial scale.
The so-called second-generation nuclear reactors produce ~16% of the total
electricity we consume (Smil 2003). Third-generation reactors, with better
safety and productivity features, went into operation a few years ago.
Fourth-generation reactors, based on totally new approaches, are in the
pipeline. But can nuclear-fission reactors dominate the energy scene for a long
time to come, resulting in the emergence of a possible nucleocultural energy
regime, superseding the present carbocultural regime?
Many people
think that they can. Sustained research and development work can perhaps make
available a large supply of fissile nuclear fuel, which may last for centuries,
if not millennia. This hope is based on the utilization of thorium, after
uranium stocks have been exhausted. Breeder reactors add further to this sense
of optimism. But all this cannot be taken for granted, because it is difficult
to predict the course of scientific and technological development.
Nuclear
fusion, rather than fission, offers another kind of hope for the possible
emergence of a nucleocultural regime, provided certain technological hurdles
can be overcome. Nuclear fusion involves the fusing together of two isotopes of
hydrogen (deuterium and tritium; or deuterium and deuterium), overcoming the
strong Coulombic repulsion between them by making their velocities very high by
heating them to ~50 million degrees Celsius. Once the Coulombic barrier has
been pierced, the very strong and attractive nuclear interaction comes into
play, and the end result is the formation of the very stable helium nucleus and
release of excess matter/energy as heat. This thermonuclear process is what has
been going on in the Sun, and is also what makes a hydrogen bomb possible.
Tritium for
this reaction must be obtained from a nuclear reaction using lithium, and the
latter is available in plenty in the Earth’s crust, and also in the seas.
Deuterium is also available limitlessly in seawater.
Both fission
and fusion operate without emitting greenhouse gases.
According to
one estimate, it may be possible to operate a commercial fusion reactor by the
end of this century. But this is only an estimate. One can never be sure about
such things. Whether or not a nucleocultural energy regime will emerge is a
difficult question to answer. The difficulty stems from the inherently
unpredictable nature of complex systems. The ecosphere is certainly a most
complex system. And so are human affairs. The complexity is not only of a
scientific or technological nature, but also involves socio-economic issues and
political decisions.
In the public
mind a major misgiving regarding nuclear reactors is about safety and long-term
health hazards from radioactive waste. This needs a close, dispassionate look,
and I shall devote the next post to it, and to some other aspects of the
nuclear-energy option.
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