Breeder reactors: Difference between revisions
(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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Nuclear fission '''breeder reactors''' are a possible alternative to [[conventional nuclear power]]. They could overcome some of its main problems. | |||
{{considerations}} __NOTOC__ | |||
==Status quo== | |||
{{sum|Not in use}} | |||
The only breeder reactors that exist are experimental/research-based, not providing electricity on a commercial scale. <!-- TALK: could we replace the word "commercial" with something more universal w.r.t. both capitalism and communism? --> | |||
==Fuel supply== | |||
{{sum|Abundant|good}} | |||
Breeder reactors | Breeder reactors can obtain [[energy]] from [[thorium-232]] and [[uranium-238]], which are far more abundant on Earth than the uranium-235 used in [[conventional nuclear reactors]]. | ||
This means that fuel scarcity would no-longer be a reason why nuclear power can't scale up and replace [[fossil fuels]]. Breeder reactor fuels, while not ''renewable'', have mineral reserves are far greater than coal, oil and gas combined (in terms of [[energy]]). | |||
<!-- TODO: add calculations --> | |||
== | ==Breeder rate== | ||
{{sum|Probably a major limitation}} | |||
Uranium-238 & thorium-232 are not directly ''fissionable'' {{light|(unlike uranium-235)}}, but they are ''fertile'' which means they can be "bred" to become fissionable materials. This where the term "breeder reactor" comes from. | |||
For this process to work, breeder reactors still need to start with ''some'' fissile material, 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. | |||
<ref>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></ref> | |||
Scientists are trying to get this down to 10 years (no guarantees). Even in such a case, it would probably still take decades to breed enough fuel to meet global energy demands {{light|(unless uranium/thorium mining could somehow be done at an extremely fast rate?{{rn}})}}. | |||
Because of this, maybe we can't count on breeder reactors to solve [[climate change]] soon enough. We'll probably still need [[wind]] and [[solar]]. | |||
==Risk of weapons proliferation== | |||
{{sum|Major risk in some cases|bad}} | |||
[[Uranium-238]] breeder reactors are '''high''' risk. | |||
{{minor|The uranium-238 is bred to become plutonium-239, which is considered "easy" to make nuclear bombs with.}} | |||
[[Thorium-232]] breeder reactors are '''lower''' risk. | |||
{{minor|The thorium-232 is bred to become uranium-233, which is considered far more difficult for making nuclear bombs.}} | |||
If breeder reactors are to become a mainstream source of energy, they have to be designed extremely securely{{en}} to prevent the possibility of anyone maliciously siphoning off some of the fissionable materials. {{rn}} | |||
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TALK: is it true that the nature of breeder reactors makes it harder to notice such "siphoning off"? if so, what could be done about it? | |||
--> | |||
==Nuclear waste== | |||
{{sum|Almost none|good}} | |||
Breeder reactors produce less than 1/1000th as much nuclear waste as conventional nuclear power{{x|Conventional nuclear power is wasteful because uranium occurs naturally as just 0.7% uranium-235; the rest is uranium-238 which goes to waste. Breeder reactors don't have this problem.}} (for the same amount of energy). | |||
==External links== | ==External links== | ||
* [https://energyeducation.ca/encyclopedia/Breeder_reactor Breeder reactor - Energy Education] - another wiki which elaborates more on the technical details | * [https://energyeducation.ca/encyclopedia/Breeder_reactor Breeder reactor - Energy Education] - another wiki which elaborates more on the technical details | ||
* http://www.world-nuclear.org/info/Current-and-Future-Generation/Fast-Neutron-Reactors/ | * [http://www.world-nuclear.org/info/Current-and-Future-Generation/Fast-Neutron-Reactors/ Fast Neutron Reactors] | ||
* [http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fasbre.html Fast breeder reactors] | * [http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fasbre.html Fast breeder reactors] | ||
====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)] | |||
==References== | |||
<references /> | |||
[[Category:Energy sources]] |
Latest revision as of 16:39, 3 November 2023
Nuclear fission breeder reactors are a possible alternative to conventional nuclear power. They could overcome some of its main problems.
Status quo
The only breeder reactors that exist are experimental/research-based, not providing electricity on a commercial scale.
Fuel supply
Breeder reactors can obtain energy from thorium-232 and uranium-238, which are far more abundant on Earth than the uranium-235 used in conventional nuclear reactors.
This means that fuel scarcity would no-longer be a reason why nuclear power can't scale up and replace fossil fuels. Breeder reactor fuels, while not renewable, have mineral reserves are far greater than coal, oil and gas combined (in terms of energy).
Breeder rate
Uranium-238 & thorium-232 are not directly fissionable (unlike uranium-235), but they are fertile which means they can be "bred" to become fissionable materials. This where the term "breeder reactor" comes from.
For this process to work, breeder reactors still need to start with some fissile material, 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. [1] Scientists are trying to get this down to 10 years (no guarantees). Even in such a case, it would probably still take decades to breed enough fuel to meet global energy demands (unless uranium/thorium mining could somehow be done at an extremely fast rate?[RESEARCH needed]).
Because of this, maybe we can't count on breeder reactors to solve climate change soon enough. We'll probably still need wind and solar.
Risk of weapons proliferation
Uranium-238 breeder reactors are high risk. The uranium-238 is bred to become plutonium-239, which is considered "easy" to make nuclear bombs with.
Thorium-232 breeder reactors are lower risk. The thorium-232 is bred to become uranium-233, which is considered far more difficult for making nuclear bombs.
If breeder reactors are to become a mainstream source of energy, they have to be designed extremely securely[ELABORATION needed] to prevent the possibility of anyone maliciously siphoning off some of the fissionable materials. [RESEARCH needed]
Nuclear waste
Breeder reactors produce less than 1/1000th as much nuclear waste as conventional nuclear power
External links
- Breeder reactor - Energy Education - another wiki which elaborates more on the technical details
- Fast Neutron Reactors
- Fast breeder reactors
Some reactor types that might show potential
- Traveling wave reactor
- Molten salt reactor (Thorium)
- Liquid metal fast breeder reactors (LMFBR) (Uranium-238)
- Supercritical-Water-Cooled Reactor (SCWR)
References
- ↑ Example quoted from energyeducation.ca:
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.
This cites another source:
World Nuclear Association. (June 19 2015). Thorium [Online], Available: http://www.world-nuclear.org/info/Current-and-Future-Generation/Thorium/#b