henry:

while progress in nuclear waste has clearly been made - any radiative waste is still potentially weaponizable presenting significant disposal problems.

How much more sustainable would be a source of ubiquitous energy without radiative nuclear complications?

NRG:

Whilst, during WWII and for many years after, special reactors in the UK and the US were used for the production of plutonium for fission bombs, the eventual success of high enrichment uranium separation with diffusion actually made the plutonium bomb obsolete in the US and the UK. India and others decided that the plutonium bomb was the cheapest for them to make because they already had operating reactors. Pakistan stole the secrets of the uranium centrifuges in Belgium to make the much easier to make uranium bomb, and is selling the secrets to others.

A comparison of the amount of plutonium and uranium left from obsolete war-heads shows the vast preference for uranium U235 from diffusion and centrifuges.

Plutonium bombs require plutonium that has high isotopic purity, and this is obtained by exposing U238 to the intense neutron flux of a reactor for just a few days, perhaps a month, until there is enough Pu239 to extract but little Pu240 or Pu241 or Pu242 or Pu244 has formed with additional neutrons added to Pu239.

Power reactors keep the uranium and plutonium in the reactor for about five years and over %25 of the electricity generated comes from the fission of Pu239 a little bit more comes from the more easy fission of Pu241. Thus the concentration of the fissionable isotopes of plutonium are kept low by the very neutron flux that creates them, and the non fissionable ones are produced. Because of the wide variety of isotopes, the plutonium from power reactors is very much more radio-active than that from weapons reactors. Queen Elizabeth once held a chunk of weapons plutonium as have many scientists in the past.

The high energy and wide variety of isotopes of plutonium extracted from power reactor fuel rods, prevents any easy direct use as an explosive weapon because the heat and radio-activity would destroy the conventional explosives required along with the detonators and electronics. Just separating the the plutonium from the 94 percent uranium and fission products is very difficult. It is economically impossible to separate even small quantities of the plutonium isotopes from each other.

The earth and the ocean have much uranium and thorium already dispersed in them. Although vast numbers of people would rise up in anger and disbelief if it were done, spent fuel rods from a single reactor, plutonium, fission products and all, could be dissolved in a large amount of water and mixed with a thousand cubic miles of seawater without increasing the radio-activity dangerously or perhaps even substantially or measurably.
The same could be done with sand in a large desert or just earth anywhere. And then there need be no special guarding or precaution in the future. The recovery of open pit mines could also be a safe enough way to dispose of slighly processed fuel rods.

Statistically, mixing the dissolved wastes into ordinary landfills is far more than good enough. Just put none in the top six to twelve feet. There is not enough total volume of spent fuel rods from all reactors to be a volumetric concern for any large municipal land fill. Heat dissipation and shielding is accomplished by adding a dilute solution of the rods to each layer and covering it using automatic or highly shielded machines.

If a UK or US person got all his direct and indirect energy from nuclear power alone, the fission products and transuranics produced would weigh about 200 grams for 100 years of energy. The weight of the spent fuel rods for a life time may be thirty times this or six kilograms. This represents the amount of energy used by a country divided by the number of inhabitants.

The production of one pound of fission products caused the release of about 10,000,000 kilowatt hours of heat. If treated carefully, one pound of weapons uranium or plutonium will actually produce 8,000,000 kilowatt hours of heat or more in current reactors.

The complications of geothermal, wind and solar energy is that, there is not enough area to collect them in places where people live and they are unconcentrated enough to make the cost of collecting them too high compared to fossil fuels or nuclear fuel. Bio-energy was shown to be insufficient in England 200 years ago before iPods. It may be economical to collect solar heat on a farm to produce hot water instead of using propane, but that is not the case for a large set of flats in York. ..HG..