Earth-bound fusion reactors that burn neutron-rich isotopes have byproducts that are anything but harmless: Energetic neutron streams comprise 80 percent of the fusion energy output of deuterium-tritium reactions and 35 percent of deuterium-deuterium reactions.
Now, an energy source consisting of 80 percent energetic neutron streams may be the perfect neutron source, but it’s truly bizarre that it would ever be hailed as the ideal electrical energy source. In fact, these neutron streams lead directly to four regrettable problems with nuclear energy: radiation damage to structures; radioactive waste; the need for biological shielding; and the potential for the production of weapons-grade plutonium 239—thus adding to the threat of nuclear weapons proliferation, not lessening it, as fusion proponents would have it.
In addition, if fusion reactors are indeed feasible—as assumed here—they would share some of the other serious problems that plague fission reactors, including tritium release, daunting coolant demands, and high operating costs. There will also be additional drawbacks that are unique to fusion devices: the use of a fuel (tritium) that is not found in nature and must be replenished by the reactor itself; and unavoidable on-site power drains that drastically reduce the electric power available for sale.
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To sum up, fusion reactors face some unique problems: a lack of a natural fuel supply (tritium), and large and irreducible electrical energy drains to offset. Because 80 percent of the energy in any reactor fueled by deuterium and tritium appears in the form of neutron streams, it is inescapable that such reactors share many of the drawbacks of fission reactors—including the production of large masses of radioactive waste and serious radiation damage to reactor components. These problems are endemic to any type of fusion reactor fueled with deuterium-tritium, so abandoning tokamaks for some other confinement concept can provide no relief.
If reactors can be made to operate using only deuterium fuel, then the tritium replenishment issue vanishes and neutron radiation damage is alleviated. But the other drawbacks remain—and reactors requiring only deuterium fueling will have greatly enhanced nuclear weapons proliferation potential.
These impediments—together with the colossal capital outlay and several additional disadvantages shared with fission reactors—will make fusion reactors more demanding to construct and operate, or reach economic practicality, than any other type of electrical energy generator.
The harsh realities of fusion belie the claims of its proponents of “unlimited, clean, safe and cheap energy.” Terrestrial fusion energy is not the ideal energy source extolled by its boosters, but to the contrary: It’s something to be shunned.