Nuclear power can be made safer, cleaner, and more sustainable than any other energy technology.
At present, its chief hindrance is the ban upon reprocessing.
It is already safer and cleaner than any fossil fuel technology is or even can be. We get 20% of our electrical energy production from reactors that require a mere 25,000 tons of uranium oxide to be supplied annually. But they only consume about a third of 0.7 percent of that.
The fissile isotope, 235U, is 0.7% of natural uranium. To make fuel grade uranium, an energy-expensive process called enrichment concentrates about half of the 235U into about one-eighth of the total uranium, which is then 3.6% fissile. It is false to attribute a carbon cost to the energy thus consumed, because it need not have been generated by coal burning. It should simply be subtracted from the electrical energy produced by the reactors. It amounts to between 0.1% and 4% of the energy which the fuel will produce.
About one-third of the energy produced by thermal-neutron reactors comes from fission of plutonium created by neutron bombardment of the otherwise inert 238U.
Note that when we split a nucleus in two, the mass of the fragments, i.e. the fission products, is just less than the mass of the fuel fissioned.
Suppose that the definition of 50% burnup is that the 235U has gone from 3.6% to 1.8%. Then for 100 tons of fuel rod uranium, we now have 1.8 tons of 235U. But the one-third implies that 0.9 tons of 239Pu have been produced and fissioned. Presumably 1.8 tons of the original 238U became 239Pu. Half of it is fissioned. Some of the remainder becomes 240Pu.
So the fission-product waste from 100 tons of fuel is 2.7 tons of uranium- and plutonium- fission products.
Note that radioactivity is inversely proportional to half-life, and most fission products have half lives measured in seconds, hours, or days.
| new rods | spent rods | radioactivity per kg. | half-life in years | |
|---|---|---|---|---|
| 238U | 96.4 | 94.6 | negligible, | 4.2 billion |
| 235U | 3.6 | 1.8 | trifling, | 700 million |
| 239Pu | 0.0 | 0.9 | slight, | 25 thousand |
| fission products | 0.0 | 2.7 | intense | up to 30 |
| Total | 100 | 100 |
| 235U consumed | 1.8 x 31.25 | 56 tons |
| 239Pu consumed | 0.9 x 31.25 | 28 tons |
| fission products | 2.7 x 31.25 | 84 tons |
There is less than 90 tons of actual unusable waste, chemically very different from the uranium-like remainder, and in principle easily separated.
But we treat all 3,125 tons as "waste" and the other part, seven-eighths of 25 thousand tons, is left lying about in canisters as the hexafluoride of "depleted" uranium.
So instead of having 90 tons a year of waste that is harmless in a few centuries, and needs only some shielding that is impervious to alpha particles, beta particles, and gamma radiation, we have chosen to burden ourselves with 3,125 tons a year of waste, most of which is less radioactive than what we put in as fuel.
The US government has already developed a technology that could use all 25 thousand tons! The class of technology is called "fast breeder reactor" and the specific project was the "Integral Fast Reactor" (IFR), canceled in a fit of monumental ignorance in 1994.