In this post, we’ll explore whether fusion energy can replace the risks associated with nuclear power. This blog post examines the potential of fusion energy, focusing on its advantages and feasibility.
Introduction
Have you heard of the Korean movie ‘Pandora’? The film depicts a scenario in which a nuclear power plant explodes due to the largest earthquake in history, causing radioactive material to leak into the air and harming many people. It follows the efforts to prevent a secondary explosion and the leakage of radioactive waste caused by shoddy construction of the plant. ‘Pandora’ conveys a lesson aimed at raising awareness of the risks of nuclear accidents that people may not fully realize and encouraging vigilance.
Nuclear power generation—the central theme of this film—is commonly referred to as a “nuclear power plant.” It is a method of generating electricity by using steam produced from the energy of a nuclear fission chain reaction to drive a turbine generator. The fission reaction that powers nuclear power plants is a type of nuclear reaction in which atomic nuclei with high mass numbers—such as uranium and plutonium—either collide with neutrons or become unstable and split into smaller atomic nuclei. When the mass of the nucleus decreases before and after fission, the difference in mass is converted into energy and released.
However, when nuclear fission occurs in a nuclear power plant, large amounts of radioactive material are produced, and a great deal of heat is generated, posing a significant risk of major accidents. The 1986 Chernobyl nuclear accident contaminated most of Europe with radiation, and the explosion at the Fukushima nuclear power plant in Japan in March 2011 spread radioactive material throughout Japan and into the Pacific Ocean. As a result of this accident, the reactor core melted down, breaching the steel pressure vessel and penetrating the concrete containment structure; the large amounts of water injected to cool the core flowed into the ocean, contaminating the local seafood with radiation. Although eight years have passed, many people are still suffering from the aftereffects of radiation, and the contaminated environment has not yet returned to its original state.
Recognizing various issues—such as the dangers of nuclear power and the controversy surrounding the disposal of radioactive waste generated during the power generation process—many countries are implementing policies to reduce nuclear power and are developing new and renewable energy sources. One such source is nuclear fusion energy.
What is nuclear fusion?
Let’s take a look at the nuclear fusion process, which generates nuclear fusion energy—a type of renewable energy. Nuclear fusion refers to the process in which nuclei with light masses, such as hydrogen, combine to form a heavier nucleus. Since the binding energy produced by nuclei lighter than an iron atom decreases as mass decreases, heavier nuclei tend to be more stable. The difference in binding energy manifests as mass deficit, generating enormous amounts of fusion energy. Furthermore, even nuclei heavier than an iron atom can fuse if external energy is supplied, allowing nuclear fusion to occur. Once fusion takes place, the resulting nuclei do not easily split apart, even if their energy decreases during the process of splitting into two nuclei. Since this process of nuclear fusion is identical to the principle by which the Sun produces light and heat, nuclear fusion devices are sometimes referred to as “artificial suns.”
Stars that generate their own energy and emit light, like the Sun, utilize nuclear fusion reactions and exist in an ultra-high-temperature plasma state exceeding 100 million degrees. In this state, atomic nuclei fuse, triggering nuclear fusion reactions that release energy. In the early 20th century, people did not understand how the Sun continuously generated such vast amounts of solar energy. According to the law of conservation of energy, the amount of energy emitted from the Sun’s surface must equal the amount of energy present inside the Sun—a feat that was impossible with the energy sources known at the time, such as wood and coal. Later, as research revealed that the Sun derives its energy from nuclear fusion, many people began studying whether this process could be harnessed for practical use.
In addition to nuclear fusion power plants, nuclear weapons developed using this technology include the hydrogen bomb. Since the hydrogen fusion reaction itself does not produce large amounts of radiation, the hydrogen bomb is relatively environmentally friendly. However, most of the hydrogen bomb’s explosive power is determined by the nuclear fusion triggered by the nuclear explosion, and the reaction cannot occur without the massive X-ray emission generated by the initial trigger mechanism. Furthermore, the current efficiency of hydrogen bombs is on par with that of an equivalent mass of TNT, so further development is still needed.
Advantages of Nuclear Fusion
Why are people conducting various studies to advance nuclear fusion technology and harness its energy? To answer this question, we must first discuss the advantages of nuclear fusion technology.
First, nuclear fusion uses naturally occurring materials as fuel. While this is a common feature of most renewable energy sources, unlike fission technology—which relies on uranium with limited reserves—nuclear fusion utilizes materials that can be easily obtained from nature. Nuclear fusion technology uses deuterium (²H), which can be obtained from seawater, and tritium (³H), produced from lithium that can be easily extracted from soil, as fuel. Hydrogen is readily available on Earth today, and even greater quantities can be obtained in space, so there is no need to worry about resource depletion.
Second, nuclear fusion is highly economical due to its extremely high fuel efficiency. The energy generated during the nuclear fusion power generation process is approximately 638 GJ per gram of hydrogen; when using the same mass of fuel, a nuclear fusion reaction produces seven times more energy than a nuclear fission reaction. Furthermore, the energy generated from 1 gram of hydrogen is comparable to that produced by 21 metric tons of coal or about 60 drums of oil, demonstrating tremendous energy efficiency.
Furthermore, nuclear fusion is a very safe technology. Nuclear fission power generation relies on a critical mass to trigger a chain reaction, maintaining a constant heat output while using a neutron moderator to control the reaction. In contrast, nuclear fusion power generation involves replenishing hydrogen fuel in the fusion reactor as needed; therefore, even if problems arise in controlling the nuclear reaction within the reactor, the risk of an explosion is virtually nonexistent. Hydrogen, the fuel for nuclear fusion power, exists in the reactor in a plasma state. Unlike solids, hydrogen plasma has a very low density and can therefore store only a small amount of thermal energy per unit volume. Consequently, if control is lost and the plasma collides with the inner wall of the reactor, the plasma dissipates and the nuclear reaction stops.
Finally, nuclear fusion is environmentally friendly and produces almost no harmful substances. The amount of radiation generated by nuclear fusion power using naturally occurring hydrogen is actually greater than that produced by nuclear fission power. However, unlike nuclear fission power—which produces radioactive materials lethal to humans—and thermal power generation—which generates and emits large amounts of harmful substances such as sulfur oxides and carbon monoxide into the atmosphere—the nuclear fusion process produces helium, which is non-radioactive and harmless to the environment, posing no harm to humans or the environment.
As such, nuclear fusion generates energy by utilizing naturally occurring materials and is economically viable due to its high efficiency. If we can harness the energy-generating mechanisms of the sun and nature, we will be able to enjoy the various benefits mentioned earlier. Therefore, at a time when the problems associated with conventional energy sources—such as resource depletion and environmental pollution—are intensifying, many countries have concluded that there is no more efficient alternative than nuclear fusion to solve humanity’s energy problems and are continuing to conduct research on nuclear fusion.
The Practical Application of Fusion
Many countries are devoting significant effort to making fusion—with its numerous benefits—a practical reality. As the scientific validation of fusion became possible, global fusion research shifted toward commercialization, with the goals of engineering applications and commercial electricity production. Accordingly, leading nations in fusion research have established international collaborative research facilities to share research findings and accelerate commercialization.
This is “ITER.” The name, which means “path” in Latin, embodies humanity’s hope for “a path toward new energy.” The ITER project is a massive international collaborative R&D initiative to jointly construct an international fusion experimental reactor, with the ultimate goal of proving the feasibility of commercial fusion energy in response to the risks of fossil fuel depletion and environmental issues. Initially led by four countries—the United States, Russia, the European Union, and Japan—the project has since been joined by South Korea, China, and India, and now consists of a total of seven countries.
The Future of Fusion
Fusion technology is steadily advancing. While cutting-edge science and technology are required to make fusion practical, a question has recently been raised: “Is it possible to achieve fusion at room temperature?”
People claiming to have achieved nuclear fusion at room temperature have consistently emerged. In March 1989, Stanley Pons and Martin Fleischmann of the University of Utah announced that they had successfully conducted a room-temperature nuclear fusion experiment. Although the experiment utilized palladium, which has the ability to absorb hydrogen, the results of the nuclear fusion reaction were inconsistent and therefore not recognized by the scientific community. Since then, various claims—such as bubble fusion reactions—have emerged, but it appears difficult to achieve room-temperature nuclear fusion with current science and technology.
Due to environmental concerns, the future energy market will be dominated by new and renewable energy sources, and since nuclear fusion energy can supply all forms of energy, it will lead the transformation of future energy supply systems. However, research on nuclear fusion energy is still in its early stages and has only just begun in earnest. Moving forward, technical challenges—such as diagnosing plasma to maintain a stable state and removing impurities—must be addressed. To this end, long-term strategies must be developed, and policies are needed to ensure a supply of talented researchers and sustained, long-term support.
Conclusion
Nuclear fusion has also been a frequent theme in recent movies. In the film ‘Iron Man’, the protagonist, Tony Stark, uses a room-temperature nuclear fusion device as the power source for his Iron Man suit. Using this device, he fights various villains and becomes a superhero. Additionally, in the movie “Spider-Man 2,” Doctor Octopus appears as a scientist researching tritium-based nuclear fusion in an attempt to gain unlimited power through nuclear fusion reactions. Although his fusion experiments failed repeatedly, the fusion reactor itself eventually becomes an entity driven by a desire to control humanity. In these films, nuclear fusion is portrayed as a technology capable of harnessing unlimited energy.
The main issue with nuclear fusion power generation is the neutron beam. A neutron beam is a stream of high-speed neutrons, and these high-speed neutrons cause the reactor to become radioactive. Unlike fission power generation, which requires isolating even large quantities of reaction byproducts from the environment, fusion power generation only requires disposal when the reactor is decommissioned; therefore, it emits far less environmentally harmful waste than fission power generation. Although the amount is smaller than that of fission, it is important to clearly recognize that radioactive waste is still produced.
I support fusion power. Fusion will bring many benefits. However, we must keep in mind that fusion technology is still evolving; while it is expected to offer numerous advantages, there may be drawbacks that have not yet been discovered.
As the history of technological advancement shows, unforeseen problems can arise and have significant consequences. Therefore, I believe it is up to humanity to determine how to utilize and harness fusion—which offers limitless potential—and that this comes with corresponding responsibility. Not only the researchers studying and developing fusion, but also the people who will use it once it is commercialized in the future, must act responsibly to prevent the misuse of fusion. Furthermore, if nuclear fusion power enables us to harness unlimited energy, we will need to devise solutions to address potential national-level issues, such as war.
