Fission

Nuclear fission is a process whereby energy is released by the splitting of uranium atoms. Fission releases heat energy that can generate steam, which is used to spin a turbine to produce electricity¹.

Uranium is the most widely used fuel for nuclear fission. Uranium is a nonrenewable energy source but it is a common metal found as an ore worldwide. Nuclear power plants use uranium, enriched in the isotope U-235 for fuel because, unlike the more common U-238, it can fission.

Uranium is extracted from the earth through traditional mining techniques or chemical leaching with major resources in Canada, Kazakhstan and Australia². Once mined, the uranium ore is sent to a processing plant to be concentrated into enriched fuel (i.e., uranium oxide pellets), which can then be used in a nuclear reactor.

In the plant’s nuclear reactor, neutrons released from fission collide with uranium atoms, releasing both heat and more neutrons. The heat is used to generate steam, which powers a turbine to generate electricity and the neutrons continue the chain-reaction.

There are many different types of reactors, each with its own benefits and drawbacks. These can be grouped into two main categories³:

• Thermal-Neutron Reactor – These are the typical reactors found around the world today, of which there are many different variations. They have issues regarding radioactive waste but generate large amounts of low carbon energy. The two most common reactors in use today are the Pressurised Water Reactor (PWR) and the Boiling Water Reactor (BWR).
• Fast-Neutron Reactors – Often considered the next step for nuclear power, fast reactors have been researched since the beginning of nuclear power but are yet to be deployed for a variety of technical, financial and political reasons. Should these issue be overcome, they could offer a revolutionary step in the way nuclear power is generated with great benefits towards waste disposal.

The first commercial nuclear fission power stations started operation in the 1950s. Today, there are over 435 operable in 31 countries. Nuclear accounts over 11% of global energy production. Nuclear Fission technology promises the world an abundant source of carbon-free energy. The costs of operation are fairly inexpensive and the nuclear fuels themselves are relatively abundant⁴.

However, there are many challenges for the technology. High costs and regulatory permitting required to construct the plants are significant barriers to the technology. Additionally, the fuel can be repurposed to create nuclear weapons, which can be a threat to national security.

The nuclear fission process also creates radioactive waste⁵, which, if not disposed of, could cause harm to the environment and surrounding communities. The safety and health of both workers and neighboring communities are also a significant concern in the event of nuclear accidents⁶.