Nuclear fuels are materials used in nuclear reactors to sustain a nuclear chain reaction. The primary fuel used is uranium, though other elements like plutonium and thorium can also be used. These fuels undergo nuclear fission, where the nuclei of atoms split, releasing a large amount of energy.
1. Common Nuclear Fuels
Uranium-235 (U-235):
Most commonly used nuclear fuel.
Found naturally in small amounts (~0.7% of natural uranium).
Enriched to increase its U-235 content for use in reactors.
Plutonium-239 (Pu-239):
Produced artificially in reactors from uranium-238.
Used in certain types of reactors, such as fast breeder reactors.
Thorium-232 (Th-232):
Abundant in nature.
Converts to fissile uranium-233 in reactors, which can then sustain a chain reaction.
2. Process of Energy Production
Nuclear Fission:
In a reactor, a neutron strikes a nucleus of the fuel (e.g., U-235), splitting it into smaller nuclei.
This releases a large amount of energy as heat, along with more neutrons.
These neutrons trigger further fission reactions, creating a chain reaction.
Heat Utilization:
The heat from fission is used to produce steam.
Steam drives turbines connected to generators, producing electricity.
3. Advantages
High energy density (a small amount of fuel produces a large amount of energy).
No greenhouse gas emissions during operation.
Reliable, continuous energy production.
4. Disadvantages
Produces radioactive waste, which requires safe, long-term storage.
Risk of nuclear accidents (e.g., Chornobyl, Fukushima).
Limited availability of fissile materials.
High initial cost for reactor construction and fuel enrichment.
5. Applications
Primarily used for electricity generation in nuclear power plants.
Fuels advanced reactors for research, medical isotope production, and naval propulsion (e.g., submarines, aircraft carriers).
Nuclear fuels offer a powerful energy source but require careful management due to the risks of radiation and waste disposal.
How do nuclear reactors differ from each other (e.g., PWR, BWR, CANDU)?
What are the safety measures in place to prevent nuclear accidents?
How is nuclear waste managed and disposed of?
What are the environmental impacts of nuclear power?
How does nuclear power compare to other forms of energy in terms of efficiency and cost?
What are some examples of major nuclear power plants around the world?