FISSION vs FUSION – the Nuclear Battle
Even though Nuclear fission is good enough for generating extreme amounts of power, the real endgame would most certainly be the manipulation and control over nuclear fusion. Fusion of two hydrogen atoms to form a single helium atom might sound fairly sober, but when it happens, it generates astronomical amounts of energy, pun intended, because it really is what lights up and powers the universe. To manipulate the tremendous amounts of energy that fusion generates, and to provide clean and sufficient energy to the world would be the single greatest thing ever to happen to humanity after the discovery of fire and the wheel; and nuclear fusion and nuclear fission would most probably be the forerunners of this task.
Nuclear fission happens when one uranium-235 or plutonium-238 atom is split into two different atoms. This releases tremendous amounts of energy, which was initially residing in the weak force. Nuclear fission is self-sustainable, which means it can go on as long as the fuel is present. Barium rods are used in nuclear power plants to control the cataclysmic reaction. Nuclear bombs use a similar concept except they don’t use barium rods which causes the fission reaction to go on, which in turn releases a humongous amount of uncontrolled energy capable of unprecedented destruction.
When one uranium-235 atom is split it generates around 200 MeV of energy. It might look a bit less, but it truly is colossal. Plutonium-238 can be used as an alternative to Uranium-235 and it works perfectly similar. Both of these are radioactive and are not found abundantly in nature. Both of them are man made and require a substantial amount of resources to produce.
Nuclear fusion happens when two deuterium or tritium atoms (Hydrogen molecules with extra protons) fuse to become one helium atom. There is a loss of mass, and that mass is converted into energy following Einstein’s famous equation E=MC². The principle of Hydrogen bomb is based on fusion only. Nuclear fusion releases stellar amounts of energy too, even more so than nuclear fission. When two deuterium atoms fuse to become one helium atom, 7 MeV of energy is released. This might look considerably less than Nuclear fission but it’s actually not when you see it from ‘energy per unit mass’ perspective.
Fission of one gram of Uranium-235 produces around one megawatt of power which equals around 3 tons of coal energy.
Fusion, on the other hand, completely exterminates its competition without any mercy. Fusion of 1 gram of hydrogen produces around 630,000 megawatts of energy. THAT REALLY IS AN INSANE AMOUNT OF ENERGY! Theoretically, with a 100% efficient machine, just 24 grams of hydrogen would be required to power the Earth for one whole year.
And that isn’t even the best thing. The best thing is actually how much of deuterium we have on our planet. You must know that we have a whopping 70% share of oceans on our cute little planet. There is enough water to cover every place on the earth with it by spreading it, and each place would be sunk around 2.5 kilometres deep. That is a lot of water. You might be wondering, “What role does water play here?” Mind you, water is basically two hydrogen atoms with one oxygen atom, both of which can be separated by electrolysis. Not every hydrogen atom in ocean water is deuterium, that is, not every part of ocean water can be used for nuclear fusion, but about 1 in 3300 hydrogens can be used for nuclear fusion (Deuterium is 0.03% of all the hydrogen present in ocean water. Protium is around 99.7%). Even that amount accounts to billions upon billions kilograms of water. To be precise, it is approximately 4,050,000,000,000,000,000 kilograms (or litres) of water. This number is difficult to visualise.
Deuterium can be inexpensively obtained from this amount of water by electrolysis (which separates hydrogen and oxygen by passing electricity through water).
Since ocean water is not really of much use to humans, the only price we will have to pay would be mostly a small amount of helium which will be formed after fusion. Helium is the least reactive gas in the entire universe, which means we won’t be having a problem regarding it.
Of course there are many, MANY other problems. The two major problems are achieving nuclear fusion in a way in which the output energy is greater than the input, and containing the fusion reaction in a containment zone. Yes, you heard read that correctly. We haven’t achieved an output which is beneficial for us in terms of power generation, and we don’t know how to control it too.
Enormous amounts of energy is required to achieve the critical temperature where hydrogen atoms can get close enough to start fusion. Turns out, hydrogen atoms hate hugging each other. Temperatures of around 1.5×10⁷ (15,000,000) ⁰C are required to to make the hydrogen atoms bond. To put that into perspective, the temperature on the surface of the sun is 5500⁰ Celsius, and the sun makes us sweat even after it is 150 million kilometres (about 93 million miles) away. No one could possibly imagine a temperature of 15 million degrees Celsius. Achieving that temperature and maintaining it is truly a big deal. Granted, the reaction thereon would be sustainable because of the even greater amount of energy (in the form of heat) emitted from fusion, but achieving it in the first place is really really difficult.
The next big problem faced by the concerned scientists and engineers for achieving sustainable fusion is the production of a solid structure which can stand still around temperatures like that and can guarantee safety in times of emergency. So far, no material has been able to withstand the wrath of fusion. Although, on the bright side, scientists are constantly innovating and inventing complex structures to survive in fusion.
The containment of fusion has been debated down to several theoretical ways. There’s magnetic mirrors, magnetic loops, electrostatic confinement and a bunch of other materials like buckyballs and graphene which have been proposed, but they still aren’t viable in any way. Magnetic confinement and Inertial confinement are two big names that come up when thinking of confining nuclear fusion reactions because of the absence of the need of any material. No material can stay solid at temperatures close to 15 million degrees Celsius, hence non-contact forces are the best bet when it comes to containing the enormous heat energy from nuclear fusion reactions.
All in all, fusion has a long way to go before becoming somewhat mainstream. Nuclear fission, once thought to be “impossible” and “pseudo science”, was achieved relatively quickly. It comes with its own set of problems for sure, but those problems are much less when compared to other power sources.
The major problems regarding Nuclear fission is the trust of people on it. Fairly large amounts of radioactive waste which is obtained from it can’t be disposed of easily. The cost and time-to-build also play a big role in nuclear fission power generating industry, both of them being fairly high, adding to the inconvenience.
The discovery of Nuclear fission and fusion are indeed works of great minds. Both of these power resources offer exceptional amounts of power from virtually unlimited fuel. As for who wins between fusion and fission – fission is what’s more economically viable right now. Despite its problems, it is what is benefiting us. Making fission lose would hurt its feelings, and we don’t wanna do that. So we’ll call it a victory for fission. Yay!
( Fusion is cooler tho ¯_(ツ)_/¯ )