Editing Breeder reactor (section)

{{Short description|Nuclear reactor generating more fissile material than it consumes}}
{{Use dmy dates|date=January 2020}}
[[File:Ebr1core.png|thumb|upright=1.25|Assembly of the core of [[Experimental Breeder Reactor I]] in [[Idaho]], [[United States]], 1951]]

A '''breeder reactor''' is a [[nuclear reactor]] that generates more [[fissile material]] than it consumes.<ref name=Waltar>{{cite book |title=Fast breeder reactors |vauthors=Waltar AE, Reynolds AB |year=1981 |publisher=Pergamon Press |location=New York |isbn=978-0-08-025983-3 |url=https://books.google.com/books?id=4m6o1jMcIIIC |access-date=4 June 2016 |url-status=live |archive-url=https://web.archive.org/web/20140105044948/http://books.google.com/books?id=4m6o1jMcIIIC |archive-date=5 January 2014}}</ref> These reactors can be [[Nuclear fuel|fueled]] with more-commonly available [[isotopes of uranium]] and [[Isotopes of thorium|thorium]], such as [[uranium-238]] and [[thorium-232]], as opposed to the rare [[uranium-235]] which is used in conventional reactors. These materials are called [[fertile material]]s since they can be bred into fuel by these breeder reactors.

Breeder reactors achieve this because their [[neutron economy]] is high enough to create more fissile fuel than they use. These extra neutrons are absorbed by the fertile material that is loaded into the reactor along with fissile fuel. This [[Irradiation|irradiated]] fertile material in turn transmutes into fissile material which can undergo [[Nuclear fission|fission reactions]].

Breeders were at first found attractive because they made more complete use of uranium fuel than [[light-water reactor]]s, but interest declined after the 1960s as more uranium reserves were found<ref name="Helmreich">Helmreich, J. E. ''Gathering Rare Ores: The Diplomacy of Uranium Acquisition, 1943–1954'', Princeton UP, 1986: ch.&nbsp;10 {{ISBN|0-7837-9349-9}}.</ref> and new methods of [[uranium enrichment]] reduced fuel costs.