Current Demand for Energy
Energy, especially when used to produce electricity, has become an essential part to our everyday lives. Everything from our computers to our cars to our factories rely (some more than others) on electricity and the energy used to produce it.
Some have even speculated that at the end of this century the demand for energy will have tripled. (3) How is the world facing such a massive, growing demand for energy? One of the most fascinating ways is by experimenting with a clean, nearly limitless nuclear power — namely, nuclear fusion. (2) Let us first examine the nuclear power of the present to better explore the future possibilities.
Nuclear Fission Process
The nuclear energy we use today is called nuclear fission. To create fission, particles (usually neutrons) are accelerated and slammed at high-speed into a large, heavy, unstable isotope (most nuclear reactors use 235U; other options are 233U, 239Pu, and 241Pu). The nucleus of the isotope absorbs the neutron, causing it to destabilize. As a result, the neutron splits into two smaller isotopes and two to three neutrons. The particles, called fissile, are ejected at a speed of about 20,000 kilometers per second. Fission also produces a massive amount of energy, which we use to heat water in nuclear reactors, beginning a process that results in the production of electricity. (1, 7) A little less than ten percent of the world’s electricity is generated by nuclear power plants. (2) According to LibreTexts Chemistry, “The energy released by fission is a million times greater than that released in chemical reactions”. (5) It should come as no surprise then that one kilogram of uranium can produce as much energy as four billion kilograms of coal. (4)
At first it may seem strange that so much energy can come out of something as small as the nucleus of an atom. The answer to this seemingly bizarre occurrence lies in Einstein’s famous equation E=mc2.
On November 21, 1905, Albert Einstein published one of his four Annus Mirabilis papers in the Annalen der Physik. It was titled “Does the Inertia of a Body Depend Upon Its Energy Content?,” and it was here that he introduced the equation. E=mc2, as explained in his paper, means the energy contained in an object (E) is equal to the object’s mass (m) times the velocity of light squared (c2). This implies that all mass is energy, in a super-concentrated form.
If you were to measure the mass of an isotope, conduct fission on it, and then add the masses of each component part the isotope split into after fission, you would find that the total mass of the isotope was larger before fission. Some of the mass “disappears” during fission. Or does it? As a matter of fact, the super-concentrated energy that was mass was released during and as a result of fission. The tiny amount of mass may not seem to have any correlation to the massive amount of energy produced by fission, but if we remember that the amount of energy is equal to the mass multiplied by the speed of light squared, things make far more sense. (4)
The amount of energy produced by fission is impressive, but it is also terrifying. Remember, fission is created when a heavy nucleus destabilizes and breaks apart. This is radioactive decay, and its side effects can be harmful and even deadly to humans exposed to it. This means fission, prone to causing meltdowns in the reactors (10), spews a massive amount of radioactive particles. (7) The risks have prompted scientists to experiment with the second way to achieve nuclear power: nuclear fusion.
Nuclear fusion is basically the opposite of nuclear fission. (9) Whereas fission occurs when an atom is ripped apart, fusion occurs when two small isotopes (Hydrogen-3 (known as Tritium) and Hydrogen-2 (known as Deuterium)) smash together and merge under massive amounts of pressure and temperature, producing a larger, heavier helium atom, a neutron, and an enormous amount of energy. (1, 2, 4) Interestingly enough, in fusion there is a mass defect, just like in fission — the fused mass is less than the masses of the individual nuclei. This is how fusion produces energy (remember, E = mc2). (4)
One of the best examples of nuclear fusion is in the cores of stars. Although fission does not usually occur in nature, fusion powers all stars, including the sun (4, 5). In his textbook Exploring Creation with Physical Science, Dr. Jay Wile says, “The enormous pressure in the core [of the sun] creates so much heat that the electrons in the hydrogen atoms [of which the sun is primarily composed] escape the attractive force the nucleus exerts on them. As a result, these hydrogen atoms are simply hydrogen nuclei. They are, in essence, ‘naked’ protons, having been stripped of their electrons.” (10) When the stripped hydrogen nuclei in the sun’s core collide, fusion occurs. (10)
Nuclear Fusion vs Nuclear Fission
But what makes fusion more desirable than fission? To put it in the words of Dr. Wile, “nuclear fusion is a clean, almost limitless source of energy.” (10) Fusion demonstrates cleanliness in many different ways. Like fission, fusion releases no CO2 or other greenhouse gases into the atmosphere. (3) Unlike fission, fusion hardly produces any radioactive waste at all, and that which it does is quick to decay. (2) It’s major by-product is helium, which is inert and non-toxic. (3) In addition, there are no risks of a meltdown during a fusion experiment. (9)
Fusion’s near-inexhaustibility are a result of the abundance of materials needed to create it. Deuterium is distilled in all water forms and tritium is reproduced during fusion reactions that involve fusion neutrons interacting with lithium. “Terrestrial reserves of lithium would permit the operation of fusion power plants for more than 1,000 years, while sea-based reserves of lithium would fulfil needs for millions of years.” (3)
In addition to being clean and unlimited, fusion produces vastly more energy than fission. Whereas fission produces about one million times more energy than chemical reactions (such as burning coal, oil, or gas), fusion produces about four million times more energy, four times the amount produced by fusion. (3)
Naturally, the fusion research has caught the eye of many. Nations across the world have begun forming grand plans for once (and if) they get a hold of the energy fusion promises. Seoul plans to let autonomous cars loose on the streets, Germany and China plan to build all-electric Mini cars, and the U.S. wants to give their military sense-enhancing, cybernetic equipment. (8) Magnetic confinement and laser-based inertial confinement are also a possibility. (4) With all these stunning possibilities, it is little wonder that discovering how to produce sufficient fusion energy is “a scientist’s dream!” (10)
However, as is the case with many dreams, reality can hold a more pessimistic view on things. Progress is slow when it comes to fusion, as it is very difficult to harness the same forces that drive the sun. (4) Let’s examine a quote from ZME Science’s article, What’s the difference between nuclear fission and fusion, by Tibi Puiu: “Normally light atoms such as hydrogen or helium don’t fuse spontaneously because the charge of their nuclei cause them to repel each other. Inside hot stars such as the sun, however, extremely high temperature and pressure rip the atoms to their constituting protons, electrons, and neutrons. Inside the core, the pressure is millions of times higher than the surface of the Earth, and the temperature reaches more than 15 million Kelvin. These conditions remain stable because the core witnesses a never-ending tug of war of expansion-contraction between the self-gravity of the sun and the thermal pressure generated by fusion in the core.” (4)
So in order to make use of fusion, scientist’s have to recreate the extreme conditions of the stars on Earth. (2) The challenges of understanding how to control a fusion reaction in a contained space has prevented any large strides of progress. (1) In the sun, fusion occurs naturally at around 15 million degrees Celsius, but in order too replicate the sun’s core on earth, six times the amount (about 100,000,000 degrees Celsius) is required to make up for the lack of immense pressure that is impossible to produce on earth. (4, 9)
However, this does not mean that technicalities prevent any progress. Fusion has been created, but as of yet all of these reactions have consumed more energy than they produce. (2, 4) Despite all this, scientists all over the world continue to pour effort into achieving fusion at a reasonable energy exchange. There are two ways scientists have approached the creation of fusion: tokamak reactors and laser fusion. ABC’s article, Fusion vs. fission: clean, green nuclear energy technologies explained, by Stuart Gary explains how the tokamak reactor works: “Tokamak reactors use a doughnut-shaped ring to house heavy and super-heavy isotopes of hydrogen, known as deuterium and tritium… These isotopes are heated to 100 million degrees Celsius by powerful electric currents within the ring. At these extreme temperatures electrons are ripped off their atoms, forming a charged plasma of hydrogen ions. Magnets confine the charged plasma to an extremely small area within the ring, maximising the chance that the superheated ions will fuse together and give off energy. The heat generated can be used to turn water into steam that spins turbines, producing electricity.” (2)
There are about two hundred tokamaks worldwide. One of the most important fusion projects is the ITER (International Thermonuclear Experimental Reactor), a “joint fusion experiment” in Southern France designed to produce ten times the energy it takes to run. The first fusion experiments with the ITER are scheduled for some time from 2025-2027. (2, 4)
Germany, China, and the UK each have their own reactors as well. Germany’s tokamak, the Wendelstein 7-X, is a different type of tokamak, called a stellarator. The stellarator design included complicated twists to increase stability and control the plasma for longer. As a matter of fact, it was the Wendelstein 7-X that proved the stellarator design correct, working as expected (though still inefficiently) when it was first turned on in 2016. (2, 4)
As of yet, China has claimed to reach tokamak temperatures of 50 million Celsius (three times hotter). Their tokamak is named the Experimental Advanced Superconducting Tokamak (EAST). (2)
“The United States, on the other hand, wants to significantly revamp the classical fusion reactor. Physicists at the Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) are proposing a more efficient shape that employs spherical tokamaks, more akin to a cored apple. The team writes that this spherical design halves the size of the hole in the doughnut, meaning we can use much lower energy magnetic fields to keep the plasma in place.” (4)
Fusion Projects and Obstacles
Laser fusion is the alternative method to achieving fusion. ABC’s previously mentioned article provides a description for this process as well: “Laser fusion uses ultra-short bursts of very powerful lasers to generate the extreme temperatures and pressures needed to trigger a fusion reaction. These laser pulses can heat and compress hydrogen isotopes to a fraction of their size, forcing them to fuse into helium and release high-energy neutrons.” The Lawrence Livermore National Laboratory’s National Ignition Facility in California uses laser pulses that release more than two million joules of energy in one nanosecond (one thousandth of a second). The one downside to laser fusion is that it is more likely for it to become radioactive. (2)
But the path to the fusion dream is hindered by yet another technicality, one that could be more challenging than the science involved with actually figuring fusion out. According to Steve Crowley, director of Culham Centre for Fusion Energy, “[fusion is] expensive research that can only be done at large scales… and nobody sees the need right now. Every time there’s talk about climate change funding goes up for awhile [but it’s not enough to even get the first reactors built]… For $20 billion in cash, I could build you a working reactor. It would be big, and maybe not very reliable… 25 years ago we didn’t even know if we’d be able to make fusion work. Now, the only question is whether we’ll be able to make it affordable.” Evidently, much more time and effort is required for sizeable progress to be made with fusion. (9)
Troubles with Cold Fusion
Perhaps the biggest reason why many people have been skeptical about fusion and don’t “see the need right now,” is because of the “cold fusion” fiasco of 1989. In BBVA OpenMind’s article Cold Fusion: Anatomy of a Scientific ‘Fraud’, Javier Yanes writes, “Nowadays if we speak to anyone without a strong scientific background about nuclear fusion as the energy of the future, they may respond with some vague reference to cold fusion,” and, “the cold fusion fiasco of 23 March 1989 has lived on almost like a cultural meme, overshadowing its legitimate nemesis, hot fusion.” (6) But what is this all about? What even is cold fusion? Why does it seem to dissuade the interests of so many, despite the tempting promises of clean, limitless, and powerful energy? An brief look into what happened may help explain much of the criticism fusion faces today.
“In the 1920s, some scientists speculated that palladium’s ability to absorb hydrogen opened up the possibility of using this metal as a catalyst that would bring atomic nuclei close enough together to achieve fusion at room temperature.” (6) This was the first idea for “cold fusion” (and now you can see where it gets its name). The idea was dismissed relatively quickly, however, and no one attempted any experiments until, in the beginning of the 1980s, electrochemist Martin Fleischmann from the University of Southampton (in the UK) rediscovered the idea. Fleischmann shared his discovery secretively with his friend and colleague Stanley Pons from the University of Utah (in the USA). Fleischmann and Pons each spent $100,000 of their own money on secretly researching cold fusion. The two worked on their cold fusion device from 1983 to 1988 and then, wanting to confirm their discovery with new experiments, asked the US Department of Energy for help with their project. The Department sent Steven Jones from Brigham Young University to help Fleischmann and Pons with the assessment of their project. Jones had been working on his own cold fusion experiments — experiments that, besides consuming more energy than they produced, had worked. (6)
Jones, Fleischmann, and Pons all agreed to send their assessment results simultaneously to the journal Nature on March 24, 1989. However, responding to pressure from the University of Utah, Fleischmann and Pons sent their results on March 23, 1989, the day before they were supposed to, by means of a statement and press conference. (6) Their announcement “shocked the world” (10) and the University of Utah threw their support behind Fleischmann and Pons. The scientific community, however, reacted with great skepticism. Almost all of the scientists that recreated Fleischmann and Pons’ experiment, including institutions investigating hot fusion such as the Massachusetts Institute of Technology, came to the same conclusion: the experiment did not work, and the results in the original experiment were caused by experimental error, not fusion. Fleischmann and Pons exiled themselves in Southern France to continue their experiments with private funding. (6, 10) There have been a large number of suspicions that Fleischmann and Pons’ announcement was a fraud, and others have accused the scientific community’s conclusions to be the same. However, no one knows for sure — there are many variables that could effect the results of a cold fusion experiment. Regardless, “cold fusion persists as one of the most cited examples of failed science.” (6)
Furure of Nuclear Energy
There should be little wonder, then, that funding today’s “hot fusion” experiments can be difficult. Instead, if people take any interest in funding nuclear research, they are more likely to consider supporting another way to generate cleaner nuclear power. People all over the world are also researching a cleaner method of producing fission. (2)
This method, first used in the 1950s, is sometimes referred to as the “thorium wildcard,” as the main idea behind this form of fission is to use thorium instead of uranium, which may be much cleaner. Thorium is also three times more abundant than uranium, the largest reserve being in Australia. So far, the United States, India, Israel, the Uk, China, Norway, Chile, and Indonesia are looking into the use of thorium fission. (2) At the very least, the thorium wildcard could provide cleaner energy until we eventually manage to master fusion.
Will we ever obtain fusion? Will it remain one of the world’s greatest mysteries for all eternity? Or, like with the lightbulb and computer, will we eventually find a way through trial and error and usher in colossal changes to the world? It is hard to predict when fusion will pay off for all the time, effort, and money poured into it over the past decade. It does, however, seem very possible for fusion to make its impact in the coming decades. In the words of Tibi Puiu, “when we do get our own sun in a jar… be ready [to] embrace the unexpected, for nothing will ever be the same again.” (4)
Bibliography
- Fission vs. Fusion – What’s the Difference?. Online. 20 January 2020.
- Fusion vs. fission: clean, green nuclear energy. Online 20 January 2020.
- Advantages of Fusion. Online. 20 January 2020.
- What’s the difference between nuclear fission and fusion. Online. 20 January 2020.
- Source 5 – Contrasting Nuclear Fission and Nuclear Fusion. Online. 20 January 2020.
- Cold Fusion: Anatomy of a Scientific ‘Fraud’. Online. 20 January 2020.
- Harnessing nuclear energy. Online. 23 January 2020.
- China’s experimental nuclear fusion reactor to go live in 2020. Online. 15 February 2020.
- Why Don’t We Have Fusion Power?. Online. 7 March 2020.
- Wile, Dr. Jay L. (2007). Exploring Creation with Physical Science. Anderson, IN: Apologia Educational Ministries, Inc.
