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(Created page with "Uranium occurs in nature as a mix of isotopes: uranium-235 (0.7%) and uranium-238 (99.3%). This proportion does not vary within the Earth's crust. * Today's nuclear reactors <small>(not breeder reactors)</small> can only get their energy from uranium-235 (U235). {{x|Technically the nuclear reactions are a bit more complex than that, but still limited by the scarcity of U235.}} * Breeder reactors can also get energy from the more abundant uranium-238 (U238). Breeder...") |
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Uranium occurs in nature as a mix of isotopes: uranium-235 (0.7%) and uranium-238 (99.3%). This proportion does not vary within the Earth's crust. | Breeder reactors are [[nuclear]] fission reactors that make better use of nuclear fuels. This could solve the problem of uranium scarcity, and also reduce [[nuclear waste]]. | ||
Breeder reactors are '''not currently''' ready for deployment. | |||
==Fuels== | |||
Uranium occurs in nature as a mix of isotopes: uranium-235 (0.7%) and uranium-238 (99.3%). This proportion does not vary much within the Earth's crust. | |||
* Today's nuclear reactors <small>(not breeder reactors)</small> can only get their [[energy]] from uranium-235 (U235). {{x|Technically the nuclear reactions are a bit more complex than that, but still limited by the scarcity of U235.}} | * Today's nuclear reactors <small>(not breeder reactors)</small> can only get their [[energy]] from uranium-235 (U235). {{x|Technically the nuclear reactions are a bit more complex than that, but still limited by the scarcity of U235.}} | ||
* Breeder reactors can | * Breeder reactors can get energy from the more abundant uranium-238 (U238). | ||
Breeder reactors can also make use of | Breeder reactors can also make use of [[thorium]]-232, which is similarly abundant. | ||
This is a more complex process than simple nuclear reactors, because thorium and U238 are not ''fissile'' materials, only ''fertile'' materials. They have to be "bred" to become fissile materials such as | This is a more complex process than simple nuclear reactors, because thorium and U238 are not ''fissile'' materials, only ''fertile'' materials. They have to be "bred" to become fissile materials such as U233, U235, or plutonium-239. | ||
Breeder reactors still need ''some'' fissile material to function, but they produce ''more'' of it than what they started with. A breeder reactor's ''doubling-time'' is a useful way to measure this: how long it takes for the reactor to produce twice as much fissile material as it started with. | Breeder reactors still need ''some'' fissile material to function, but they produce ''more'' of it than what they started with. A breeder reactor's ''doubling-time'' is a useful way to measure this: how long it takes for the reactor to produce twice as much fissile material as it started with. Breeder reactors ''so far'' have a doubling-time of over 100 years, unfortunately. {{p|Example quoted from [https://energyeducation.ca/encyclopedia/Breeder_reactor energyeducation.ca]:<br /><q>Thorium hasn't been used in large scale reactors, however some reactors have used it successfully in the past. A light water breeder reactor in Shippingport, Pa. USA operated for 5 years, and by the end of its operation it had 1.4% more fissile fuel than it began with.</q><br /><br />This cites another source:<br /><small>World Nuclear Association. (June 19 2015). Thorium [Online], Available: http://www.world-nuclear.org/info/Current-and-Future-Generation/Thorium/#b</small>}} Scientists are trying to get this down to 10 years. Even in such a case, '''it would still take decades''' to breed enough fuel to meet global energy demands. | ||
Thus we can't count on breeder reactors to solve [[climate change]] soon enough. We still have to work on other [[energy]] sources too, such as [[wind]] and [[solar]]. | Thus we can't count on breeder reactors to solve [[climate change]] soon enough. We still have to work on other [[energy]] sources too, such as [[wind]] and [[solar]]. | ||
==Types== | ==Types== | ||
Some reactor types that might show potential: | |||
* [https://en.wikipedia.org/wiki/Traveling_wave_reactor Traveling wave reactor] | |||
* [https://www.iaea.org/topics/molten-salt-reactors Molten salt reactor] (Thorium) | |||
* [https://www.sciencedirect.com/topics/earth-and-planetary-sciences/liquid-metal-fast-breeder-reactor Liquid metal fast breeder reactors (LMFBR)] (Uranium-238) | |||
* [ | * [https://www.gen-4.org/gif/jcms/c_42151/supercritical-water-cooled-reactor-scwr Supercritical-Water-Cooled Reactor (SCWR)] | ||
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==External links== | ==External links== |