Harnessing the Power of the Sun: Nuclear Fusion
A world with virtually limitless energy is hard to imagine; everything either runs out or is too ineffective of an energy source. Take solar energy, for example; it doesn’t work on cloudy days, and when it does work, we can’t contain an effective amount of energy. However, what if we could bring a part of the sun to earth? Enter Nuclear Fusion.
Nuclear Fusion is when two atoms smash together to form a heavier atom, like two hydrogen atoms to a single helium atom. This is the main process of energy for stars. Nuclear fusion is why our Sun can heat us up from billions of kilometers away. This usually occurs in the core of stars; however, to achieve nuclear fusion, the atoms must be moving at such a high speed (or heat) to overcome their repulsion from each other. Stars, instead, use the pressure of their mass to squeeze the atoms together, fusing them into heavier elements. This fusion of elements is what releases energy, and it is what is hoped to be achieved through nuclear fusion reactors.
This is not the same as the reactors from Chernobyl or the nuclear reactors that produce radioactive waste. Those reactors are called “nuclear fission reactors”. As by the name, instead of fusing atoms together, nuclear fission is when atoms are broken apart, releasing a huge amount of energy. However, nuclear fission is not usually found in nature, and like most man-made processes, there are many dire consequences posed to nature if the reaction gets out of control. The famous Chernobyl reaction, and countless others, are evidence of the harmful effects of this process.
However, nuclear fusion doesn’t pose as many harmful effects; if the confinement for the reaction fails, the plasma in the reaction would easily cool down, and the reaction would stop. The biggest problem with nuclear fusion is the feasibility of such a reactor. Many people say that a feasible nuclear reactor is 10–30 years away, or maybe even impossible, as the energy inputted to make the reactor is much more than the energy received.
Let’s say we wanted to make a fusion reactor. How would we achieve it?
Making a Fusion Reactor
To make a fusion reactor, we have to think of the origin of nuclear fusion; stars. Nuclear fusion most often occurs with hydrogen or helium, so the fuel for the reactor would be hydrogen or helium. If we’re thinking of a natural fuel source, seawater would be the most logical source: it’s filled with hydrogen. However, normal hydrogen wouldn’t work; hydrogen with extra neutrons, hydrogen isotopes, would function better: like Deuterium and Tritium. Deuterium is abundant in seawater as well, but Tritium is much harder to find, as it’s radioactive. We would need to find something else to use, and based on research, Helium-3, an isotope of Helium, might be a much better substitute. Yet, much like Tritium, it’s very difficult to find on Earth. Thankfully, it’s abundant on the Moon; with these 2 elements, a fusion reactor is very feasible. Now, how would we achieve fusion?
The Methods of Fusion
At the moment, there are 2 main ways of making plasma that would allow atoms to be hot enough to fuse: magnetic and inertial confinement.
Magnetic confinement uses a magnetic field to squeeze plasma, in a doughnut-like chamber. These reactors use electromagnets cooled with liquid helium, which are usually kept at temperatures very close to absolute zero. As a result, these kinds of fusion reactors contain one of, if not the largest temperature ranges in the world.
Inertial confinement uses pulses from lasers to heat up a pellet of fuel, therefore imploding it, and making it hot and dense enough to fuse.
There are many companies trying to achieve a viable nuclear fusion, and projects looking to achieve the same thing. One of these projects are the I.T.E.R. in southern Frace (International Thermonuclear Experimental Reactor), and they’re hoping to finish by 2025.
35 different nations are cooperating to bring this project to fruition.
There is also the Commonwealth Fusion Systems (CFS), which are building and testing many fusion reactors. The “Alcator C-Mod: Plasma Physics Basis”, located at MIT, tests the viability of nuclear fusion, and the environments to achieve such fusion.
Fusion reactors would be such an effective source of power, yet at this present moment, it’s quite difficult to achieve an effective reactor. When we do further this technology enough, however, fusion reactor will likely be the dominant energy source in the world.
