Let's Meet Atom

A week ago I wrote how we need to be clear-headed and shouldn't abandon nuclear energy in the face of the tragedy in Japan. I still hold to this position, but recognize the importance of fully understanding the implications of using nuclear fission energy. We need to have a solid understanding of the burden we’re transferring to future generations by selecting nuclear energy, because with this choice comes enormous responsibility. Nuclear waste from fission energy will, after all, be on our planet for thousands of years. We can't predict the consequences of this and we can't provide solutions to some of the problems our descendants might face as a result. We need to adjust our tendency to be short-sighted in this regard and understand that what we create now is interconnected to the fate of our descendants.

I want to state that I no longer think that fossil fuels are a viable option for our energy requirements. I understand that our measures to eliminate them must proceed slowly, but their impact on our planet in the form of climate change isn't acceptable.

Let’s meet Atom. I am not a nuclear physicist, so I will explain this in the very rudimentary way that I understand it.

In order to create nuclear fission energy, the nucleus of an atom is split, resulting in gamma rays from the free photons and neutrons. These free neutrons then continue the reaction by striking other atoms, causing them to split and thereby resulting in yet more free neutrons, which further continues this chain reaction. This is the controlled reaction that takes place inside a nuclear reactor. Heat is then produced from two types of energy released: electromagnetic in the form of gamma rays and kinetic energy in the form of the actual fragments of the subatomic particles splitting. The heat is used to generate steam and thus electricity.

In understanding the chain reaction aspect of nuclear fission, we can appreciate that this is an enormous cause of concern regarding the management of it. Although it’s controlled, as in the Daiichi Plant in Japan, we can clearly see the consequences when this controlled environment is compromised and we are rendered ineffective to handle this chain reaction.

Uranium is one of the nuclear fuels which can sustain fission and is used in a nuclear reactor, allowing for significantly greater amounts of energy per unit mass than fossil fuels are able to provide. The amount of energy from nuclear is abundant and this should serve as a reminder of our great responsibility in how we control it but also as a warning of how we’re unable to control it.

Some major concerns surrounding nuclear energy and uranium in general are the dangers inherent in mining it, the possible use of enriched unranium for nuclear weapons, and the fears of disasters like Chernobyl and in Japan . Even so, the data clearly shows that overall, there are fewer deaths associated with nuclear energy than with any other form of energy currently being used.

One of the greatest pitfalls of nuclear fission energy is nuclear waste that remains radioactive for thousands of years. When looking at this, we must look at our responsibility to future generations as we don’t have long-term solutions for this. Spent fuel rods have enormous amounts of radiation and we have to find a way to properly store them. Currently, we store the spent fuel rods in storage pools to cool them down for a few months, but this often becomes storage for several years. After this, some are placed in dry cask storage for additional temporary storage until a solution is agreed upon. Overall, we’re uncertain where to store these highly radioactive spent fuel rods for thousands of years. Some proposals are: burying it under the ocean floor, storing it underground or shooting it into space. These options don’t come without pitfalls.

Furthermore, it’s impossible to predict some of the consequences our descendants might face as a result of the storage we choose. After all, the harnessing of nuclear energy for power has only been available to humans for 66 years. Yet we’re taking this relatively new form of human-harnessed energy and are deciding what the fate of its waste will be for thousands of years to come. Our descendants might not think fondly of our choices and we must consider what their wishes might be. They are a part of this equation whether we like it or not.

On a hopeful note, New Scientist had a relevant op=ed piece discussing some problems and potential solutions of possible alternatives. It said:

Because most nuclear power plants have been adapted from reactors developed for military applications, they are not necessarily the best designs. Of those, a handful of plants are notorious: Three Mile Island, Chernobyl and now Fukushima.

This raises a question: what if nuclear reactors were designed from first principles, simply as a means to produce power with as little risk as possible? Such thought experiments can be useful.

In the case of nuclear power, this approach could bring great benefits. One good example is the liquid fluoride thorium reactor, which as the name suggests, relies on the element thorium as a less risky alternative to uranium. Though the technology is as yet unproven, these reactors promise tantalising safety advantages. These include cooling systems that sidestep the risk of hydrogen explosions of the kind that shattered Fukushima.

Overall, scientists are diligently working to find other forms of energy to move away from fossil fuels and better forms of nuclear energy. For now, these are hopeful forms that someday will come to fruition in the form of clean and sustainable energies. Until then, we should look to nuclear fission with a solid awareness of all of its consequences and especially our responsibility to our descendants.