FUSION ENERGY: IS IT WORTH IT?
by Abdullah Nabeen
What if there was a way to get an inexhaustible source of energy? Fusion energy is the answer to that. Fusion energy is simple – quite the opposite of fission energy, comes from splitting an atom and is usually used to power nuclear plants. If by mentioning fusion, you thought of space then, you’re not too far off because fusion occurs constantly in sun. The sun gets most of its energy through the nuclear fusion of hydrogen atoms that fused together to form helium.
Now, you’re probably wondering what makes fusion energy so great over fission energy. Fusion energy doesn’t produce runaway chain reactions the way fission can, so there’s no need to worry about meltdowns like Fukushima. But that’s not where the benefits stops. Fusion reactions cannot produce large amounts of dangerous radioactive waste the way fission does. That’s why it’s such a dreamy source of energy.
So why do we have fission power, but not fusion power? The answer is simple and a very frustrating one to lot of scientists. For fusion to work on earth we need to produce a temperature of at least 100 million degrees Celsius, which is six times hotter than Sun itself. To understand why fusion energy needs such a high temperature, we have to look back at our knowledge in atoms. Normally, fusion is not possible because we have to collide and fuse the strongly repulsive forces of positively nuclei. However, the reason the Sun is able to accomplish such feat is because of its massive gravitational forces, pressure, and high temperature. So, based on the collision theory, high pressure and temperature could make nuclei overcome the repulsive forces to the extent that they come close. Therefore, the attractive nuclear force will outweigh the repulsive force allowing the nuclei to fuse together. Thus, to create such an energy on earth, we need six times the temperature to cover the lower gravitational force than sun. And that’s where the term cold fusion, the hope that fusion reactions can occur at low temperature, comes in handy.
Now, you’re probably wondering what makes fusion energy so great over fission energy. Fusion energy doesn’t produce runaway chain reactions the way fission can, so there’s no need to worry about meltdowns like Fukushima. But that’s not where the benefits stops. Fusion reactions cannot produce large amounts of dangerous radioactive waste the way fission does. That’s why it’s such a dreamy source of energy.
So why do we have fission power, but not fusion power? The answer is simple and a very frustrating one to lot of scientists. For fusion to work on earth we need to produce a temperature of at least 100 million degrees Celsius, which is six times hotter than Sun itself. To understand why fusion energy needs such a high temperature, we have to look back at our knowledge in atoms. Normally, fusion is not possible because we have to collide and fuse the strongly repulsive forces of positively nuclei. However, the reason the Sun is able to accomplish such feat is because of its massive gravitational forces, pressure, and high temperature. So, based on the collision theory, high pressure and temperature could make nuclei overcome the repulsive forces to the extent that they come close. Therefore, the attractive nuclear force will outweigh the repulsive force allowing the nuclei to fuse together. Thus, to create such an energy on earth, we need six times the temperature to cover the lower gravitational force than sun. And that’s where the term cold fusion, the hope that fusion reactions can occur at low temperature, comes in handy.
It’s not that we are far off from creating such technology but nobody sees the need to spend on large scale expensive research right now. Today we can create fusion reactions in tokamak – torus (donut) shaped. A tokamak works by generating magnetic fields, created by magnetic coils, which are strong enough to keep plasma (the gas inside tokamak get charged and become plasma) from escaping the tokamak. This mimics the pressure of sun’s core. Then radio and microwaves are fired into the plasma to raise its temperature and around 100 million degree fusion occurs. However the reason why Stewart C. Pager of the Princeton Plasma Physics Laboratory called this process a grand scientific challenge is: the high cost of electricity to heat the chamber, finding material that can withstand heat and to sustain this reaction longer than few minutes. Pager points out that reaction outputs have come a long way in the past few decades –from milliwatts in the 1970s to sixteen million watts. Now, the only question remains whether well ‘be able to make it affordable.