Saturday, 5 January 2013

61. The Imperial Approach to System Earth

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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