Saturday, 19 March 2011


Fusion power would provide much more energy for a given weight of fuel than any technology currently in use,[20] and the fuel itself (primarily deuterium) exists abundantly in the Earth's ocean: about 1 in 6500 hydrogen atoms in seawater is deuterium.[21] Although this may seem a low proportion (about 0.015%), because nuclear fusion reactions are so much more energetic than chemical combustion and seawater is easier to access and more plentiful than fossil fuels, some experts estimate that fusion could supply the world's energy needs for millions of years.[22][23]

An important aspect of fusion energy in contrast to many other energy sources is that the cost of production does not suffer from diseconomies of scale. The cost of wind energy, for example, goes up as the optimal locations are developed first, while further generators must be sited in less ideal conditions. With fusion energy, the production cost will not increase much, even if large numbers of plants are built. It has been suggested[by whom?] that even 100 times the current energy consumption of the world is possible.

Some problems which are expected to be an issue in this century such as fresh water shortages can actually be regarded merely as problems of energy supply. For example, in desalination plants, seawater can be purified through distillation or reverse osmosis. However, these processes are energy intensive. Even if the first fusion plants are not competitive with alternative sources, fusion could still become competitive if large scale desalination requires more power than the alternatives are able to provide. Furthermore, as refining suggested fusion fuels (deuterium, and tritium) via distillation of hydrogen or electrolysis from seawater would produce a waste product of pure hydrogen the fusion plants themselves could produce a small amount of drinking water by reclaiming the lost energy. At perfect conditions this would be to produce 1g deuterium per 30 kg of water worth of hydrogen.[citation needed].

Despite being technically non-renewable, fusion power has many of the benefits of long-term renewable energy sources (such as being a sustainable energy supply compared to presently utilized sources and emitting no greenhouse gases) as well as some of the benefits of the much more limited energy sources as hydrocarbons and nuclear fission (without reprocessing). Like these currently dominant energy sources, fusion could provide very high power-generation density and uninterrupted power delivery (due to the fact that it is not dependent on the weather, unlike wind and solar power).

A scenario has been presented of the effect of the commercialization of fusion power on the future of human civilization.[24] ITER and later Demo are envisioned to bring online the first commercial nuclear fusion energy reactor by 2050. Using this as the starting point and the history of the uptake of nuclear fission reactors as a guide, the scenario depicts a not unreasonable rapid take up of nuclear fusion energy starting after the middle of this century. Because the development of fusion energy is such a complex technological task it is probable that there will be several decades when the constraints of energy shortage will be severely felt as shown by the flattening of the energy consumption from around 2040 to 2100. Such a period of stagnation seems unavoidable even with the envisaged development and rapid adoption of fusion energy. On the other hand without nuclear fusion energy the scenario depicts a severe downturn with world population shrinking below 5 billion and eventually even lower

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