Nuclear Fission

Three notable nuclear fission incidents have shaped public perception: the Three Mile Island accident (USA, 1979), the Chernobyl disaster (USSR, 1986), and the Fukushima crisis (Japan, 2011).

The fission process is based on uranium-235 atoms, which are the building blocks of matter and emit radioactive rays when they undergo fission. This process is leveraged to generate electricity.

To initiate fission, uranium atoms must be bombarded with neutrons—particles that, alongside protons, form the atomic structure. The stability of an atom is maintained when neutrons and protons are balanced. Introducing extra neutrons destabilizes the atom, leading to its splitting.

During the fission process, three key events occur:

1. Emission of Radioactive Rays: These rays disperse in water and are contained by reactor walls.
2. Heat Generation: The reaction produces heat, raising water temperatures significantly (up to 350°C or 662°F). While water typically turns to steam at 100°C (212°F), it remains liquid under pressure in this scenario.
3. Neutron Release: The neutrons released from the fissioning uranium atoms propagate the reaction by splitting other uranium atoms.

The heat generated from fission is harnessed to drive turbines and alternators, subsequently generating electricity.

Nuclear Fusion

The first controlled nuclear fusion reaction took place during Operation Ivy Mike in 1952, a hydrogen bomb test.

The sun generates energy through nuclear fusion, combining around 620 million tons of hydrogen every second. Fusion occurs when two light atomic nuclei merge to create a heavier nucleus, utilizing elements like hydrogen and its isotopes, deuterium and tritium, which yield helium as a result.

This fusion process also releases a significant amount of energy. Just like in fission, this energy heats water, producing steam that drives turbines for electricity generation.

Achieving fusion necessitates extreme conditions of temperature (in the tens of millions of degrees) and pressure to overcome the electrostatic repulsion between the atomic nuclei. This is why developing functional fusion technology is challenging, as replicating the sun's conditions in a lab setting is complex.

Fusion is highly coveted due to its potential as a nearly limitless and clean energy source, producing minimal long-term radioactive waste.

Fission vs. Fusion: A Comparative Overview

Transitioning from fossil fuels, nuclear power plants have helped prevent the release of nearly 2 gigatonnes of CO2 annually. Both nuclear fission and fusion present unique mechanisms, benefits, and challenges in energy production.

While fission generates substantial energy, it also produces long-lived radioactive waste and carries environmental risks. Conversely, nuclear fusion offers a nearly infinite energy source with reduced radioactive waste and lower risks of accidents.

Fusion reactors are considered safer because they are less likely to maintain a self-sustaining chain reaction; any loss of control will halt the fusion process. Nevertheless, creating and sustaining the extreme conditions required for fusion poses a significant obstacle.

To be viable, fusion must yield more energy than it consumes—a target that has yet to be consistently met.

Final Thoughts

Nuclear energy encompasses two contrasting methodologies for power generation: fission, a well-established technology, and fusion, which emulates the sun's energy production. While fission provides considerable energy output, it comes with challenges related to radioactive waste and accident risks. In contrast, fusion represents a promising, cleaner energy solution with fewer safety concerns, yet it still faces substantial hurdles in practical implementation.

What’s your stance on nuclear power? Thank you for reading, and I hope to see you in the next article!

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