Editing Enriched uranium (section)

==Cost issues==

In addition to the separative work units provided by an enrichment facility, the other important parameter to be considered is the mass of natural uranium (NU) that is needed to yield a desired mass of enriched uranium. As with the number of SWUs, the amount of feed material required will also depend on the level of enrichment desired and upon the amount of <sup>235</sup>U that ends up in the depleted uranium. However, unlike the number of SWUs required during enrichment, which increases with decreasing levels of <sup>235</sup>U in the depleted stream, the amount of NU needed will decrease with decreasing levels of <sup>235</sup>U that end up in the DU.

For example, in the enrichment of LEU for use in a light water reactor it is typical for the enriched stream to contain 3.6% <sup>235</sup>U (as compared to 0.7% in NU) while the depleted stream contains 0.2% to 0.3% <sup>235</sup>U. In order to produce one kilogram of this LEU it would require approximately 8 kilograms of NU and 4.5 SWU if the DU stream was allowed to have 0.3% <sup>235</sup>U. On the other hand, if the depleted stream had only 0.2% <sup>235</sup>U, then it would require just 6.7 kilograms of NU, but nearly 5.7 SWU of enrichment. Because the amount of NU required and the number of SWUs required during enrichment change in opposite directions, if NU is cheap and enrichment services are more expensive, then the operators will typically choose to allow more <sup>235</sup>U to be left in the DU stream whereas if NU is more expensive and enrichment is less so, then they would choose the opposite.

When converting uranium ([[hexafluoride]], hex for short) to metal, 0.3% is lost during manufacturing.<ref>{{cite web |
url=https://inis.iaea.org/collection/NCLCollectionStore/_Public/02/014/2014451.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://inis.iaea.org/collection/NCLCollectionStore/_Public/02/014/2014451.pdf |archive-date=2022-10-09 |url-status=live |
title=Economics of blending, a case study | 
last=Balakrishnan |
first=M. R. |
publisher=Government of India, Atomic Energy Commission |
location=Bombay, India |
page=6 |
date=1971 |
access-date=7 November 2021 }}</ref><ref>{{cite web |
url=https://books.google.com/books?id=PteWDwOTK08C&q=conversion+losses&pg=PA29 |
title=Costs of nuclear power | 
last=US Atomic Energy Commission |
publisher=Office of Technical Services, Dept of Commerce |
location=Washington DC |
page=29 |
date=January 1961 |
access-date=7 November 2021 }}</ref>