Environmental Engineering Reference
In-Depth Information
the plasma. Wall erosion is also a maintenance problem, complicated by the fact that
the
first wall materials will become radioactive and require special handling.
An analysis of the availability in the sea of deuteriumand lithium for a possible but
probably unlikely age of fusion-produced electric power has been given by MacKay
([44], p. 172). Seawater contains 33 g of deuterium per ton, and this is a huge supply.
Each gram of deuterium represents 100,000 kWh, and the sea contains 197 million
tons of seawater per person (at 7.0 billion humans). Lithium is also available in
seawater at 0.17 ppm, which translates [44] to 3910 tons of lithium per person. If the
lithiumproduces 2300 kWh per gramin the fusion reactors, and the energy usage per
person is 105 kWh/day, then this energy source would last for over a million years.
The success of the ITER reactor is not guaranteed, and even so it is not a power reactor
but a research reactor. In the words of David MacKay [44], I think it is reckless to
assume that the fusion problem will be cracked.
Even if the problem is cracked, it is clear that a fusion reactor has to be large, a
contributor to a power grid. While the fusion reactor seems quite safe, has no
meltdown possibilities, and leaves few radioactive waste products, if indeed the
engineering of the well-known science into a useful power reactor design succeeds,
the end product will be very high technology only possible on a large scale, with high
demands on an operator to make it work smoothly.
