Nuclear fission

Types

• Conventional nuclear power - used by all reactors today
• Breeder reactors - not operational yet

Basic physics

A nuclear reaction is far more energy-dense than a chemical reaction. Whereas combustion of fossil fuels involves splitting molecules, nuclear fission involves splitting atoms. This requires a fissionable material, such as uranium (which has large unstable atoms that split easily).

See Wikipedia for a much more detailed explanation of the physics.

Role in ending climate change

Conventional nuclear power can't scale up enough to replace fossil fuels, because it relies on uranium-235 which is too scarce. Breeder reactors could potentially be a solution to this problem, by making use of far-more-abundant materials such as uranium-238 and thorium. The technology for this is not quite ready yet. ^{[ELABORATION needed]}