The growing demand for energy in developed and developing countries and the threats of the ongoing climate emergency have motivated researchers, policymakers, and the public to put high hopes on next-generation alternative sources of energy. Power generation through nuclear fusion or fusion power is a proposed safer alternative to nuclear fission power and another cleaner and greener alternative to hydrocarbons.
There are two types of nuclear reaction: fusion and fission. Power generation via nuclear fission is a proven alternative energy source. It involves splitting the nucleus of heavy elements such as uranium to trigger a nuclear reaction and release a large amount of energy.
On the other hand, nuclear fusion is a reaction resulting from the merging of two or more atomic nuclei and the formation of a heavier nucleus. Fusion power involves the use of light elements such as the isotopes of hydrogen as the main fuel for a fusion-based reactor. The process generally centers on producing and using heat from nuclear fusion or thermonuclear reactions to drive turbines or harness kinetic energy and produce electricity.
Advantages of Nuclear Fusion Power
Imitating how the sun and the stars produce energy is the main goal of nuclear fusion power. There are several reasons why this is beneficial. The power of the sun seems limitless. Of course, it is bound to exhaust all of its fuel in time but it still has billions of years before it collapses and becomes reduced to a black hole. Furthermore, the heat produced by the sun is different from burning fossil fuels. It is not also as radioactive as fission-induced nuclear reactions.
1. Safer Alternative to Nuclear Fission and Cleaner Alternative to Fossil Fuels
One of the main advantages of nuclear fusion power is that it lacks the risks that come from power generation via nuclear fission such as reduced radioactivity and little high-level nuclear waste. Physician and anti-nuclear advocate Helen Mary Caldicott argued that existing nuclear power plants remain at risk of possible nuclear meltdowns induced by human error, natural calamities, and terrorist attacks.
The Three Mile Island incident in 1979 and the Chernobyl disaster in 1986 remain the prime examples of human-induced risks of nuclear fission power plants while the Fukushima nuclear disaster caused by the earthquake and tsunami that struck Japan in 2011 exemplified the susceptibility of these power plants toward meltdowns due to natural calamity.
Furthermore, it is also important to note that fission reaction produces radioactive nuclear wastes from nuclear reaction and the decommission and dismantling of reactors and facilities. The United States Nuclear Regulatory Commission considers spent uranium fuel as a high-level waste that emits radiation at doses fatal to most living organisms even during short periods of direct exposure. High-level wastes require remote handling and shielding.
Radioactive isotopes of spent uranium can also enter the food chain and expose a larger population of species if they get into groundwater. There are standards for handling spent fuel, as well as for maintaining a fission power plant. However, radioactive leakage remains a possibility because of the inherent susceptibility of fission reactors to nuclear meltdowns.
Nuclear fusion produces nuclear wastes at a level considerably far lower than the wastes produced from nuclear fission. The International Atomic Energy Agency explains that a fusion reaction involving hydrogen isotopes deuterium and tritium produces radioactive tritium. But the half-life of this radioactive material is short. Tritium is also used in low amounts and as such, its radioactive byproduct is only few and easier to handle and store.
Researchers Sandri et al. reviewed radioactive wastes production at experimental nuclear fusion facilities do not present critical issues from the perspective of radioactivity and the negative impacts of the exposure on the population. The selection of materials and procedures at these facilities enable a simplified management of radioactive wastes.
A fusion reactor is not susceptible to a meltdown. System failures during a fusion process would simply stop the ongoing nuclear reaction and stabilize the involved fuel elements. This is not the case in nuclear fission. Reactions must be contained before the process goes from critical to a supercritical state. A supercritical state indicates excessive heat generation that melts down the uranium core and compromises the structural integrity of the reactor.
Of course, apart from being a safer alternative to nuclear fission, another advantage of power generation via nuclear fusion is that it is a cleaner method than burning hydrocarbons or fossil fuels and one of the most environmentally friendly sources of energy. It produces zero greenhouse gases and other harmful atmospheric emissions.
2. Abundance and Availability of Required Elements as Fuels Needed for Fusion Reaction
Stars demonstrate the most readily observable occurrence of nuclear fusion transpiring in the natural environment. The massiveness of these astronomical objects produces enough pressure to bind nuclei together while producing extreme temperatures to trigger a nuclear reaction. A star shines for most of its lifespan due to the thermonuclear fusion of hydrogen into helium in its core. Humans do not have the technology to replicate this process.
However, instead of using pressure, experimental laboratories have been conducting fusion tests that involve subjecting hydrogen isotopes to high temperatures to produce a thermonuclear reaction. The involved hydrogen isotopes are deuterium and tritium. Note that deuterium is naturally abundant in oceans and can be obtained by processing ordinary water.
Naturally occurring tritium is extremely rare on Earth. Artificially production is possible through irradiation of lithium metal or lithium-bearing ceramic pebbles but the entire process is inefficient. These facts collectively represent one of the issues and disadvantages of nuclear fusion power. However, there are other alternatives. These include deuterium-deuterium fusion, deuterium-helium-3, and proton-boron-11 fusions.
A deuterium-helium-3 fusion has been regarded as a second-generation approach to controlled nuclear fusion. There are promises from this alternative. Note that deuterium-tritium fusion remains the most economical because it requires a lower temperature than deuterium-deuterium fusion but it has high irradiation doses that generate wastes and embrittle materials
On the other hand, a deuterium-helium-3 has a higher temperature requirement of about four times than the temperature requirement of a deuterium-tritium fusion. However, it makes up for this shortcoming because it theoretically addresses the issue of excess waste production. The reaction produces helium and hydrogen but no neutron. The problem with neutrons is that they bombard the surrounding surface and transfer their energy to the cooling system.
A helium-3-helium-3 fusion is also another option. In an article by Mark Williams Pontin of the MIT Technology Review, he quoted Gerald L. Kulcinski, the Director of the Fusion Technology Institute at the University of Wisconsin-Madison, who said that this alternative is the most promising because it produces non-radioactive byproduct.
The aforesaid alternative also produces protons instead of neutrons. These protons can be contained using electric and magnetic fields and their energy can be converted directly into electricity. A reactor based on this approach can fundamentally generate electricity both from heat-driven turbines and the energy potential of protons. A helium-3-helium-3 fusion also does not need a massive containment vessel used in deuterium-tritium fusion
Helium-3 is rare on Earth but researchers noted that it is abundant on the Moon. The study by Thomas Simko and Matthew Grey noted that it would take USD 17 billion to construct a mining facility on the surface of the Moon. However, this investment is commercially viable over the medium term considering the economic value of helium-3.
3. Social, Economic, and Environmental Benefits From a Clean and Limitless Energy Source
The International Energy Agency mentioned that the demand for electricity is growing at a rate faster than the capabilities of the world to develop renewable sources of energy. Furthermore, this demand also pushes further the existing dependence on fossil fuels, thus threatening the targeted limits of carbon dioxide emission and pushing back climate emergency response. The increasing electricity demand is needed to sustain global economic growth.
A report from Meghan Gordon and Maya Weber of S&P Global also noted that the energy demand will grow to 47 percent by 2050. The current direction of Asian economies will be among the main drivers of this growth. In addition, while renewables will gain a better foothold in the global energy mix, Asian countries will drive the demand for oil and gas.
Energy security is critical for economic growth. The study of Thai-Ha Le and Canh Phuc Nguyen that involved a global sample of 74 countries showed that energy security measures positively correlated with enhanced economic growth while energy insecurity seemed to negatively affect the economic progress of a particular country. These suggested that economic development should be attuned to policies related to energy security.
Access to energy is also a determinant of poverty. A review study by S. Jessel, S. Sawyer, and D. Hernandez explained that household energy has become increasingly important in maintaining good health. Poor access to energy has been linked with poor health. The researchers suggest that future studies should look more into the link between poverty, health, and energy security.
Nevertheless, because of the advantages of nuclear fusion power, developing and promoting this alternative source of energy can result in specific social, economic, and environmental benefits. The possibility of affordable electricity will mean connecting more people in underdeveloped and developing countries to national power grids. The social impacts of these possibilities will transpire both on the micro and macro levels of society.
Clean energy is essential in sustaining or inducing economic growth without the negative impacts of conventional energy sources such as fossil fuels. Nuclear fusion promises to deliver both clean and affordable electricity. This can power energy-dependent industries and sectors, as well as usher in an era of electricity-based modes of transportation.
Renewable energy sources such as solar power, wind power, hydropower, and geothermal power are also clean. However, their generation capacity is a problem. It is impossible for them to power large communities such as megacities and metropolitans. They are also intermittent. Solar power and wind power depend on batteries. Furthermore, renewable facilities take up land resources. Nuclear power is a more beneficial alternative.
Note that the other general advantages of nuclear power regardless if it is based on fusion or fission power include better efficiency than fossil fuels and improved reliability than renewables, and versatility from producing electricity and supporting non-electric industrial and social applications such as saltwater desalination and district heating.
Disadvantages of Nuclear Fusion Power
The disadvantages of nuclear fusion power collectively center on the existing and pressing challenges concerning its commercial application and implementation for widespread rollout. The fact remains that this supposed cleaner and better alternative source of energy remains a concept. There are attempts to produce fusion reactions in laboratories. Some of these were successful but they are not enough for actual power generation.
1. Fundamental Reasons Behind the Challenges in Inducing Fusion Reaction
It is important to reintroduce the fundamental process behind a fusion reaction to understand better why nuclear fusion power remains challenging and almost close to impossible. For starters, under normal scenarios, this reaction is impossible to take place on Earth. The strong repulsive electrostatic forces between positively charged nuclei prevent them from getting close enough together to collide and trigger a fusion reaction.
Remember that the fusion transpiring in stars is possible because of gravity-induced pressure that allow positively charged particles to collide. The intense pressure also produces intense heat to trigger a nuclear reaction. Scientists approach nuclear fusion not through the use of pressure but through extreme heat. This is the primary offshoot of fusion power.
The goal of nuclear fusion power is to generate power or produce electricity. However, based on existing technologies and the overarching concept behind human-induced nuclear reaction via fusion, doing so would mean using energy as an input. It essentially means using energy to produce heat. Of course, this is also true in other power generation approached. However, for an approach to be possible, the output should be substantially greater than the input.
2. Energy-Positive Goal and the Realities of Exiting Technologies and Techniques
Scientists working at different fusion reactors and laboratories across the world are continuously conducting tests and experiments to improve their processes and achieve energy-positive nuclear fusion power. An energy-positive result means that the energy output produced by the nuclear reaction is substantially higher than the energy input. An energy-negative result means that the entire endeavor is cost-inefficient and uneconomical.
Note that a standard deuterium-tritium fusion requires a temperature above 100 million Kelvin. This is six times hotter than the core of the Sun. Remember that this is the most economical among all other fusion approaches. A deuterium-deuterium fusion requires a temperature of between 300 million Kelvin to 500 million Kelvin.
Producing the required temperature requires high energy input. The current experiments showed problems not only in producing energy-positive results but also in sustaining the resulting nuclear reaction. There is a need to produce a sustained reaction for the entire thermonuclear reaction process to produce and release a usable amount of energy that can be used to drive turbines or harness kinetic energy for electricity production.
3. Costs and Economic Considerations as the Main Problem of Nuclear Fusion Power
The European Union reported that it spent close to USD 10 billion in the 1990s to research and develop capabilities for nuclear fusion power. The United States government under its Department of Energy has been allocating between USD 360 million to USD 671 million each year since 2010 for the same endeavor. It is evident that the U.S. has been increasing its spending to further research and refine its fusion capabilities.
Nevertheless, based on the figures above, one of the disadvantages of nuclear fusion power is cost. All relevant undertakings transpiring in different laboratories remain conceptual and the entire technology is still in its infancy. It is also important to highlight the fact that the costs of these endeavors are shouldered through public funding.
The real problem surfaces when investments in next-generation nuclear power technology are compared against investments in other alternative sources of energy such as renewables. Some have argued that the amount used in the development and operations of fusion reactors will be channeled into the development of renewable energy technologies.
Considering the fact that fusion power has not produced results that create a semblance of commercial feasibility, it is understandable that some sectors of the public would protest against existing initiatives. Some economists have even computed the costs and compared them with actual economic value. Results of these computations showed that the costs remain higher than the expected economic value due to the absence of significant developments.
Remember that the primary challenge centers on the fact that a fusion reaction requires expending large amounts of energy. There are costs attached to this energy requirement on top of all other costs used in operating and maintaining facilities. Hence, current capabilities suggest that generating electricity from nuclear fusion remains counterproductive.
FURTHER READINGS AND REFERENCES
- Caldicott, H. 2006. Nuclear Power Is Not The Answer To Global Warming And Anything Else. The New York Press. ISBN: 978-0522852516
- Gordon, M. and Weber, M. 2021. “Global Energy Demand to Grow 47% By 2050, With Oil Still Top Source.” S&P Global. Available online
- International Atomic Energy Agency. n.d. “Fusion.” International Atomic Energy Agency. Available online
- International Energy Agency. 2021. “Global Electricity Demand is Growing Faster than Renewables.” International Energy Agency. Available online
- Jessel, S., Sawyer, S., and Hernández, D. 2019. “Energy, Poverty, and Health in Climate Change: A Comprehensive Review of an Emerging Literature.” Frontiers in Public Health. 7. DOI: 10.3389/fpubh.2019.00357
- Le, T-H. and Nguyen, C. P. 2019. “Is Energy Security a Driver for Economic Growth? Evidence From a Global Sample. Energy Policy. 129: 431-451. DOI: 10.1016/j.enpol.2019.02.038
- Pontin, M. W. 2007. “Mining the Moon.” MIT Technology Review. Massachusetts Institute of Technology. Available online
- Sandri, S., Contessa, G. M., D’Arienzo, M., Guardati, M., Guarracino, M., Poggi, C., and Villari, R. 2020. “A Review of Radioactive Wastes Production and Potential Environmental Releases at Experimental Nuclear Fusion Facilities.” Environments. 7(1): 6. DOI: 10.3390/environments7010006
- Simko, T., and Gray, M. 2014. “Lunar Helium-3 Fuel for Nuclear Fusion.” World Futures Review. 6(2): 158-171. DOI: 10.1177/1946756714536142
- United States Nuclear Regulatory Commission. 2019. “Backgrounder on Radioactive Waste.” U.S. NRC Fact Sheets and Brochures. United States Nuclear Regulatory Commission. Available online