Increasing energy demands and climate change call for a replacement of fossil fuels and nuclear energy might be the answer. Nuclear energy technology has not changed much since the first nuclear reactor was built. Throughout the years only minor improvements were made to make them safer and more efficient but the main functions remain the same. Despite there being two different methods of creating nuclear energy (fission and fusion) we are only able to properly use one with desirable outcomes.
Discovery and history of nuclear fission
Nuclear fission is the process when one heavy nucleus splits into two lighter nuclei. Fission was discovered by two German scientists, Otto Hahn and Fritz Strassman, in 1938. Hahn and Strassman fired neutrons from a source containing the elements’ radium and beryllium into uranium and found remaining elements much lighter with less than half the atomic mass of uranium. Hahn and Strassman sent their findings to Lise Meitner before publicizing their work (Belloc, 1967). Meitner found when she added the atomic masses of the leftover material, they did not equal the uranium’s mass. Meitner used Einstein’s theory to show the lost mass changed to energy, this proved fission occurred and confirmed Einstein’s work (Belloc, 1967). After the discovery of nuclear fission, many scientists began to believe a self-sustaining chain reaction was possible. Enrico Fermi and his assistant Leo Szilard proposed the design for the uranium chain reactor. They were successful in their efforts and the self-sustaining chain reaction occurred on December 1942.
Types of nuclear fission reactors
There are several types of nuclear reactors including Boiling Water (BWR) and Pressurized Water (PWR). Pressurized and Boiling Water reactors are the most common making up most of the nuclear reactors in the world. The United States Nuclear Regulatory Commission explains a typical Boiling Water reactor should do the following:
1. The core inside the reactor vessel produces heat.
2. A steam-water mixture is produced when pure water (reactor coolant) moves upward through the core, absorbing heat.
3. The stream-water mixture leaves the top of the core and enters two stages of moisture separator where water droplets are removed before the steam is allowed to enter the steamline.
4. The steamline directs the steam to the main turbine, causing it to turn the turbine generator, producing electricity.
Any unused steam is exhausted to the condenser, where it is condensed into water. The water is pumped out of the condenser, reheated, and pumped back into the reactor vessel. Pressurized water reactors operate in a similar manner, The United States Nuclear Regulatory Commission states they should do the following:
1. The core inside the reactor creates heat
2. Pressurized in the primary coolant loop carries the heat to the steam generator.
3. Inside the steam generator, heat from the primary coolant loop vaporizes the water in a secondary loop, producing steam.
4. The steamline directs steam to the main turbine, causing it to turn the turbine generator, which produces electricity.
Unused steam is exhausted to the condenser, where it is turned into water. The water is pumped out of the condenser, reheated, and pumped back into the steam generator.
Issue and accidents
Most of the energy in the world is produced using fossil fuels, 11 percent of the world’s energy is produced by nuclear power. However, nuclear reactors can produce much more energy than coal or oil, nor does it release air pollutants. However, there are huge risks in having nuclear reactors, the most notable being a meltdown. The risk of a meltdown makes safety the number one priority when constructing a fission reactor. A meltdown occurs when the nuclear reaction within a core is not controlled and temperatures rise high enough to melt the uranium. The high temperatures can also lead to an explosion, without proper containment radiation could leak into the environment. A similar event occurred in Chernobyl, Ukraine 1986 since then the production of nuclear reactors quickly slowed down through the fear of another Chernobyl occurring. However, contrary to normal belief nuclear fission reactors are safer than a fossil fuel power plant. Public opinion of nuclear reactors drastically fell either way despite that fact.
Future of nuclear energy
Nuclear Fusion is the process of fusing two small nuclei into a single larger nucleus. Nuclear fusion is a much more complicated and difficult process extremely high temperatures are required to get atoms to fuse. There are currently two different fusion reactor designs that are popular one being magnetic confinement and the other inertial confinement. The magnetic confinement method uses strong magnetic fields to contain the hot plasma. Inertial confinement involves compressing a small pellet containing fusion fuel to extremely high densities using strong lasers or particle beams (“Nuclear Fusion: WNA – World Nuclear Association”, 2017). Fusion reactors do not release any form of pollutant, this is one of the biggest advantages fusion reactors have over fission reactors. Fusion reactors also use hydrogen, deuterium and tritium, as fuel sources which are cheaper than fossil fuels, in the long run, fusion reactors can produce 3 times more energy than fission reactors, and if a malfunction occurs there is no risk of an explosion the reaction will just stop. There are several countries conducting experiments to find a way of making fusion reactors a viable source of energy. Currently, fusion reactors output less energy than what was initially invested. Conducting experiments for fusion technology is extremely expensive, and the cost along with the difficulty may mean fusion reactors may never be commercially viable.
Nuclear fusion reactors could be possible soon as scientists are close to producing results that could make them viable. With the means to produce plenty of clean energy climate change can be stopped. Even if creating an efficient nuclear fusion reactor is not yet plausible, improving nuclear fission reactors and increasing safety is still an option right now.