Conventional small nuclear reactors
Small nuclear reactors use conventional nuclear power but are much smaller than your typical nuclear power plant. They're suited only for very specialized operations (less than 0.01% of the world's energy use). Despite any hype you may have heard, they are not a viable way to replace fossil fuels.
Examples of usage
- Naval propulsion reactors, used in military ships & submarines
- Truck-sized reactors, used for powering very remote military bases
Considerations
Weapons proliferation
A small nuclear reactor can't be regulated as tightly as a large nuclear power plant. It's harder to prevent someone from stealing some uranium and using it to make a nuclear bomb. There are still some redundant safety measures in place, but not as many as a large nuclear power plant has. The uranium in small reactors is also more enriched (even higher than weapons grade, in some cases) which is unfortunately essential to how small reactors work.
- For a list of historical examples of stolen uranium & plutonium, see this external link: Information on Nuclear Smuggling Incidents
- Notice that the most serious incidents (i.e. more than a Hiroshima-equivalent amount stolen) tend to involve small nuclear reactors (such as naval submarines) with highly-enriched uranium.
This risk would be greatly amplified if small nuclear power were to become a mainstream energy source instead of a small niche.
Fuel scarcity
See page on conventional nuclear power: Uranium-235 is too scarce to replace fossil fuels. Maybe breeder reactors could overcome this someday, by using the more abundant uranium-238 or thorium.
Research needed
- Breeder reactors - would it be possible invent a new type of small nuclear reactor, powered by thorium? Would it be safer? [new page needed]