|
|
| (9 intermediate revisions by the same user not shown) |
| Line 1: |
Line 1: |
| ==Fission== | | ==Types== |
| [[Nuclear fission]] is what's currently used in all of today's nuclear power plants. Fission derives [[energy]] from heavy radioactive elements - in particular, [[uranium]]. | | <!-- |
| | * '''[[Conventional nuclear power]]''' - '''status quo''', used by all nuclear power plants today |
| | * [[Breeder reactors]] {{light|(thorium or uranium)}} - not ''quite'' viable yet |
| | * [[Nuclear fusion]] - not viable yet |
| | --> |
| | {|class='wikitable' |
| | !rowspan='2' |Type of nuclear power |
| | !colspan='3' |Problems if scaled up |
| | |- |
| | !Fuel scarcity |
| | !Weapons proliferation |
| | !Nuclear waste |
| | |- |
| | |[[Conventional nuclear power]] |
| | |{{rcell}} Problem |
| | |Low risk |
| | |{{rcell}} Problem |
| | |- |
| | |[[Conventional small nuclear reactors]] |
| | |{{rcell}} Problem |
| | |{{rcell}} High risk |
| | |{{rcell}} Problem |
| | |- |
| | |Uranium-238 [[breeder reactors]] |
| | |Abundant |
| | |{{rcell}} High risk |
| | |Almost none |
| | |- |
| | |[[Thorium]]-232 breeder reactors |
| | |Abundant |
| | |Low risk |
| | |Almost none |
| | |- |
| | |Hydrogen [[fusion]] {{light|(not viable yet)}} |
| | |Abundant |
| | |Low risk |
| | |Almost none |
| | |} |
| | <big>So far, it seems that '''[[thorium]]''' is the only nuclear power that could really [[scale up nuclear power|scale up]] enough to replace all [[fossil fuels]].</big> |
|
| |
|
| ===Supply===
| | [[Category:Energy sources]] |
| Uranium is a mineral that occurs naturally as ''a mix of two isotopes'': uranium-238 (99.3%) and uranium-235 (0.7%). The proportion does not vary in nature. Current nuclear reactors can only derive energy from the uranium-235 part.
| |
| | |
| If the whole world was powered ''only'' by nuclear fission, we'd start to run out of uranium-235 in '''less than 4 years''':
| |
| {{dp
| |
| |<nowiki>uranium.reserves</nowiki>
| |
| |<nowiki>8.070 million tonnes uranium_natural</nowiki>
| |
| |<nowiki>Global uranium mineral reserves, measured in energy units</nowiki>
| |
| |<nowiki>The calculator understands "tonnes uranium_natural" as an energy unit. It's based on the fact that natural uranium is just 0.7% uranium-235 (the isotope we extract energy from). The rest is uranium-238, which isn't useful for energy unless we use breeder reactors.</nowiki><br /><nowiki>
| |
| </nowiki><br /><nowiki>
| |
| Citation:</nowiki><br /><nowiki>
| |
| Uranium 2020: Resources, Production and Demand ('Red Book')</nowiki><br /><nowiki>
| |
| "The total recoverable identified resources to $260/kg U is 8.070 million tonnes U."</nowiki><br /><nowiki>
| |
| </nowiki>
| |
| }}
| |
| {{dp
| |
| |<nowiki>nuclear_power_plant.efficiency</nowiki>
| |
| |<nowiki>33%</nowiki>
| |
| |<nowiki>Electrical output divided by the heat energy of the nuclear reactor</nowiki>
| |
| |<nowiki>Nuclear power plants convert heat (from uranium-235, currently) into electricity. The process is approximately 33% efficient.</nowiki><br /><nowiki>
| |
| </nowiki><br /><nowiki>
| |
| Citation: Key World Energy Statistics 2020 (IEA report) - Page 73 - Glossary - Nuclear</nowiki>
| |
| }}
| |
| {{dp
| |
| |<nowiki>energy.tfc</nowiki>
| |
| |<nowiki>9937.70 Mtoe/year</nowiki>
| |
| |<nowiki>Global energy usage - total final consumption (TFC)</nowiki>
| |
| |<nowiki>Includes: fuel (80.7%) + electricity (19.3%) AFTER it is generated.</nowiki><br /><nowiki>
| |
| </nowiki><br /><nowiki>
| |
| Does not include the fuel used in generating electricity. See [energy.tes] for that.</nowiki><br /><nowiki>
| |
| </nowiki><br /><nowiki>
| |
| Citation: "Key World Energy Statistics 2020" IEA</nowiki><br /><nowiki>
| |
| - Page 47 - Simplified energy balance table - World energy balance, 2018</nowiki>
| |
| }}
| |
| {{calc
| |
| |<nowiki>uranium.reserves * nuclear_power_plant.efficiency</nowiki>
| |
| |<nowiki>years energy.tfc</nowiki>
| |
| }}
| |
| We'd run out even faster [[energy demand scenarios|if all nations were developed]].
| |
| | |
| Potential solutions:
| |
| * Using nuclear power '''only''' as a [[baseload]] (in other words, only for the electricity that '''has to''' be available 24/7). Other energy could come from [[solar]] and [[wind]].
| |
| * Extracting [[uranium from seawater]] (but the viability of this is questionable (like [[lithium|other trace minerals]]), because the concentration is extremely low).
| |
| * [[Breeder reactors]] could make use of uranium-238 (and also [[thorium]] which is somewhat more abundant than uranium).
| |
| | |
| | |
| ===Safety concerns===
| |
| ====Proliferation====
| |
| If uranium gets into the wrong hands, it can be used to make [[thermonuclear bombs]]. Nuclear power plants need strong redundant security measures to mitigate this risk.
| |
| ====Meltdowns====
| |
| This has happened twice in history: [[Chernobyl]] and [[Fukushima]].
| |
| <!-- TODO: put in perspective the number of lives lost and the amount of land lost, relative to the amount of energy generated (throughout all of history). Compare to fossil fuels etc. -->
| |
| | |
| | |
| | |
| ==Fusion==
| |
| [[Nuclear fusion]] is '''not''' currently viable for generating power. Scientists are working on it - because in theory, it could power the world for millions of years, from only tiny amounts of abundant material, and with almost no pollution. Fusion has the potential to completely solve the [[energy]] crisis, but it is nowhere near ready yet (despite some misleading news headlines). It's certainly worthwhile to invest time & money into fusion, but we can't "put all our eggs in one basket". [[Climate change]] is near a [[tipping point]], so we need clean [[energy]] sooner than fusion might be available.
| |