#total nuclearization

It’s difficult to understand why anyone would ever say that small nuclear reactors would lead to the production of less waste, and yet we have seen the claim made, repeatedly. For a given reactor type, the smaller the core, the greater the loss of neutrons by leakage. This means that the initial fuel charge must have a greater proportion of fissile material, and less of it is consumed before the operating reactivity margin falls too low and it must be replaced.

This study, however, doesn’t make a great deal of sense. The authors concentrate on two factors which are both probably irrelevant. The first is neutron activation of steel — specifically the steel of the reactor pressure vessel. The first reason that this is surprising is that the main constitutents of steel, iron and carbon, do not generally become transformed into radioactive isotopes by interaction with neutrons, and especially not long-lived, energetic radioisotopes. About the only substance commonly found in steel that does become so activated is cobalt, and so that element is typically excluded from reactor construction. (There is also some possibility of neutron absorption in molybdenum to form technetium.) Since the half-life of cobalt-60 is less than 6 years, irradiated stainless steels and other nickel alloys containing traces of cobalt can, if necessary, be held for 60 years for the activity to decay, before being mixed with other scrap steel.

Now, neutron collisions move atoms out of their places in the crystal lattice of a solid material. This happens much more often than the absorption of neutrons to create new (and sometimes radioactive) nuclei. As a result, inside the typical reactor pressure vessel you will find something called a “thermal shield”. This is a steel liner, which is under no structural load, so that changes in its mechanical properties as a result of such displacements, known as “neutron embrittlement”, don’t hurt anything. In other words, its whole function is to stop neutrons from getting to the pressure vessel (which is frequently lined with stainless steel, which in turn may contain traces of cobalt). And since this thermal shield is constructed of materials which do not become strongly and long-lastingly radioactive under neutron bombardment, it can be treated as normal scrap steel after a moderate cooling-off period.

The second factor they consider is radiotoxicity of plutonium in the fuel wastes. This, it seems to us, reflects a fundamental misunderstanding of the role of the small reactor. The large nuclear power reactor is very economical in meeting the energy needs of large cities. In the absence of anti-nuclear political pressure, the demand for such reactors tends to be strong. While there are many potential applications for small reactors, relatively few of them are so economically or technically compelling that they are likely to be pursued, absent a strong commitment to shifting the overall energy supply towards fission.

The University of Illinois is interested in installing a nuclear reactor as part of their total energy supply plant.

This is an idea which has quite the history, going back to the Ågesta reactor in Sweden. The SLOWPOKE Energy System developed by AECL circa 1980 was specifically targeted at users like university campuses.

Given that UIUC, although it had a research reactor once upon a time, has not had one in operation for some 30 years, this could be a great opportunity to provide facilities ranging from practical experience in reactor operation, to neutron irradiation and isotope production, for the engineering and sciences programs.

It has been repeatedly claimed that the recycling of nuclear fuel is uneconomical as opposed to shoving it down a hole in the ground.  This seems to rest on two bases, firstly that the cost of reprocessing is high, & secondly that the value of the recovered fuels is low, on the basis of current or reasonably foreseeable future prices of uranium.

To the first point, it is reasonable to think that industry can develop less costly methods than those originally created, on a “hurry-up” basis, for extracting plutonium for making bombs.  Even the present methods would undoubtedly be cheaper on a larger scale.

The ostensible subject matter of this article is minimally relevant.  The United States gave up its lead in nuclear energy decades ago, & is unlikely to get it back before more decades have passed, if ever.  No, the meat is near the bottom.

The debate over the test reactor mirrors a larger one over the future of nuclear energy, says Mark Hibbs, policy analyst with the Carnegie Institution for International Peace in Berlin. If nuclear energy provides a bridge to other carbon-free sources such as wind and solar, fast reactors won't be needed, he says. But if nuclear energy will be needed for centuries—as China anticipates—then utilities must eventually switch to fuel-breeding fast reactors, Hibbs says. The debate, he says, "is dominated by theology and lobbyists."

A transition to a fully nuclear energy supply is necessary.

Why?  Every halfway-competent investigation has shown that less land, less raw material, less capital ― less, in other words, of human & natural resources is used by an energy system, the greater the proportion of fission in the mix.  And the less of those resources used in supplying energy, the more that can be put to use for the actual work of civilization, or simply left alone.  That means more food, more goods, more leisure, more wild land, more biodiversity.