4.5 Summary of Week 4

Figure 14

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This is an image depicting nuclear fusion.

Figure 14

At the moment, most of our power comes from the burning of fossil fuels, which release carbon dioxide and water when burnt.

These are greenhouse gases and contribute to the greenhouse effect and global warming. Because of these environmental concerns and the finite nature of fossil fuels, alternative resources are being pursued, one of which is nuclear energy.

In order to meet the UK’s energy requirements, a new nuclear power station is being constructed at Hinkley Point in Somerset. It has enhanced safety features in order to protect the core and to contain it in the event of a meltdown. It is also expected to produce significantly less nuclear waste compared to older type reactors. Research is being done elsewhere on using thorium as a nuclear fuel rather than uranium or plutonium. This would particularly advantage countries that have reserves of thorium.

Another technology that is being pursued is nuclear fusion. Like nuclear fission, this also involves changes within the nucleus itself but involves bonding light nuclei together rather than splitting heavy nuclei apart.

Fusion reactions power the stars but it is very difficult to achieve on Earth as the two nuclei are both positively charged and require very high energies to overcome the repulsion. To date, nuclear fusion has not attained the status of a workable energy resource but research is progressing at NIF in the US and ITER in France.