Nuclear fission is a reaction in which the nucleus is split and torn, and while controlled fusion is the hope of the future, controlled fission is not yet a reality.
Although nuclear power was of little interest in the decades after the Fukushima Daiichi disaster, growing concerns about global warming have brought it back to the table. National Geographic described nuclear fusion in 2019 as the “holy grail” of the future of the nuclear powers. The fact that controlled fission is at least short-term and economic, as shown in Figure 1, proves this.
It would not only produce safer energy, but also produce less radioactive waste, such as spent fuel rods, which take millions of years to decay and require extremely careful and expensive storage.
At the other end of the process, fusion requires much less fuel than fission, but the fuel is much easier to obtain. Fusion requires tritium, which can be produced from lithium in the reactor itself, and only a small amount of uranium, a rare substance that needs to be degraded and enriched. It produces zero nuclear waste because its fuel is hydrogen, not uranium or plutonium. Nuclear fission requires many rare substances, such as uranium and plutonium, or rare metals such as thorium and boron, which must have been depleted or enriched, while nuclear fusion is a much more common and cheaper fuel source for nuclear power plants.
The dream of nuclear fusion has long been out of reach, but only this week the world’s largest nuclear fusion experiment achieved a major breakthrough. With the introduction of Jeff Bezos – backed by General Fusion – and a huge pool of merger startups fueling competition, fusion is finally becoming a reality.
The multinational project, based in the south of France, announced the historic milestone, which marks the culmination of a decade of research and development by the team of scientists and engineers from the University of California, Berkeley and the National Renewable Energy Laboratory.
The idea of a fusion-fission hybrid reactor has existed for decades, with the earliest indication attributed to Russian nuclear physicist Andrei Sakharov. In essence, nuclear fusion is used as a substitute for fissile material in the production of nuclear energy and as an alternative to traditional fission – the generation of energy based on nuclear fission. First, the use of neutrons derived from fusion to feed an f-nuclear reaction would massively expand the fuel available for the operation of a plant. Then a fusion-fission hybrid reactor would use the fusion reactor to provide the neutron as a cover for the fISSile materials.
In a world where we are trying to reduce the spread of nuclear weapons, the existence of a nuclear fusion reactor could lead to the clandestine production of plutonium 239. If this is the case, nuclear fission reactors may have to continue to operate in order to supply this source. Fusion reactors will continue to pose a significant radiation risk and huge amounts of water will be needed to cool the thermal power plants.
In order to achieve an economically sustainable production model, it is time for the researchers to make the process significantly safer and, over time, more efficient.
Realistically, there is no way to provide truly sustainable, zero-carbon energy on the scale required in the foreseeable future. While fission technology is much closer to hand, fusion breeding has had to go through a much longer development process than was the case due to the fact that it is only a fraction of the cost of a nuclear power plant and only about half as fast. A rapid rupture would require the use of much more energy than current nuclear generation.
Nuclear fission – the suppression of hybrid fusion is not a new idea; it was first proposed by Andrei Sakharov in the 1950s and endorsed by Hans Bethe in 1979 (10-11). For decades, it has been argued that current research efforts to develop fusion reactors should shift their focus from pure fusion to a design known as fission-suppressing hybrid fusion.
The production of electrical energy from pure fusion uses the kinetic energy of neutrons to bring water to boil, and the simple fusion reaction combines deuterons and triton to produce electricity, which can be achieved through the fusion of hydrogen and helium, the two most abundant elements in the universe.
Figure 2 shows that fission is the opposite of fusion, which means that the product has less mass than the nucleon when a heavy nucleus is fissioned, because the mass is destroyed and no energy is released in the reaction. As stated in nuclear fusion, energy cannot be released if the products of a nuclear reaction have energy that is bound to BE. However, when the heavy nuclei are split (as in fusion), the heavier nucleus can be split and energy released, but not vice versa.