Nuclear energy is widely considered to be the safest source of energy in the world, but the potential for a nuclear meltdown is still a cause for concern. Using simple statistics, the probability of a core melting accident within one year of reactor operation is estimated to be 1 in 3704 reactor years. Despite this low probability, there have been two major accidents at nuclear power plants, and their impacts have been much less serious than previously feared. In light of these findings, researchers are calling for an in-depth analysis and reassessment of the risks associated with nuclear power plants. The impact of nuclear accidents has been a topic of debate since the first nuclear reactors were built in 1954. This has been a key factor in public concern for nuclear facilities, and despite the efforts of operators to maintain control, the reactor cores in units 1-3 at Fukushima Daiichi overheated, leading to the melting of nuclear fuel and the breaking of three containment vessels.
In 1970, there were doubts about the ability of emergency cooling systems to cope with an accident involving loss of coolant and consequent melting of the fuel core. If a building were to fail and dust were released into the environment, it was determined that the release of a given mass of fission products that had aged for almost thirty years would have a smaller effect than the release of the same mass of fission products (in the same chemical and physical form) that had only undergone a short cooling time (for example, one hour) after the nuclear reaction had ended. Soon after the Chernobyl accident, it became clear that the main impacts of nuclear accidents are not radiological, but socio-economic and psychological, driven by misconceptions about radiation's health effects. To gain a better understanding of these probabilities, more transparency is needed from the International Atomic Energy Agency (IAEA). The number of core melting accidents that can be expected over time in nuclear power plants is higher than previously expected. In a modern reactor, a nuclear fusion must be contained within the reactor containment structure. The MKER design offers improved safety and unique benefits that make it competitive in countries considering full fuel cycle options for nuclear development.
The VHTR is expected to be prototyped and tested at Idaho National Laboratory within the next decade (starting in 200), based on the design selected for the Next Generation Nuclear Power Plant by the United States Department of Energy. The IAEA defines a nuclear and radiation accident as an event that has had significant consequences for people, the environment or the facility. However, they do not publish a historical database of these accidents, likely due to their dual role as both regulator and promoter of the nuclear industry. A more detailed analysis of these probabilities requires more transparency from IAEA. In conclusion, while nuclear energy is still considered to be one of the safest sources of energy available today, it is important to understand that there is still a risk associated with it.