Are the radiological risks exaggerated? How safe are nuclear power plants?

Elon Musk recently suggested that Europe resume investing in nuclear power plants to reduce its energy dependence on Russia. His statement “Radiation risks are exaggerated” indicated that the risk of radiation is much, much lower than most people realize. However, how many agree with that?

The recent fire at the Zaporizhzhia nuclear power plant in Ukraine due to Russian bombing has sent shock waves across the world. Although the fire at one of Europe’s largest nuclear power stations was quickly brought under control and there were no reports of casualties or major damage, the world stopped at the incident as it risked repeating the nuclear disaster.

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It was not the first time that Ukraine had a serious radiation leakage problem. Memories of the 1986 radioactive leak accident at the Chernobyl nuclear power plant in Ukraine still remain fresh for many. At that time, Ukraine was part of the former USSR or the Soviet Union. The city of Chernobyl still remains a ghost town and the general population is not allowed to enter the area surrounding the power plant due to the high radiation to date.

Chernobyl nuclear power plant covered under an iron dome

(Image source: © Svedoliver | Megapixl.com)

Is the risk worth taking?

The fire at the Zaporizhzhia nuclear power plant has sparked a decade-old debate about the safety of nuclear energy. We all know the benefits of nuclear power such as reliable 24/7 supply, zero carbon emissions and the potential to help reduce dependence on fossil fuels like coal. and petroleum.

However, the consequences of the nuclear disasters of Chernobyl and Fukushima make us reflect on the value of the risk to be taken.

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In the current scenario, where the use of fossil fuels is increasing, the average temperature of the Earth and the renewable energies available are not sufficient factors to meet the demand, nuclear energy seems to be the obvious answer.

Nuclear power plants, which emerged in the 1950s, account for around 10% of the world’s electricity supply from around 440 reactors. Only 32 countries operate nuclear power plants and more than 50 countries benefit from the grid supply system.

So we come to our original question, how safe are these nuclear power plants? The answer to this question is not easy because it involves many technical analyzes of the entire process of electricity generation, from the enrichment of uranium to the safe disposal of nuclear waste.

Natural uranium is not radioactive and cannot be used as fuel. It requires enrichment and processing to make fissile material for use in reactors. A reactor is a place where a nuclear chain reaction takes place and heat is released which is then used to produce steam to run the generator turbine.

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How safe are nuclear power plants?

The right question is how secure is the security? Like any high-end technology that has the potential for mass destruction, it comes with many fail-safe systems. Companies involved in the construction and operation of a nuclear power plant perform several tests based on different scenarios that can lead to a potential failure.

Events such as large magnitude earthquakes, cyclones, floods, fires, failure of containment area or cooling system or backup supports are all considered in the design and construction phase. planning. Mock exercises are conducted before factories become operational.

The two most common methods of nuclear power plant risk assessment employed by designers are deterministic methods and probabilistic methods. Under the deterministic method, the design team postulates an accident, assumes a single failure criterion, and then includes the failure of the backup system that would be placed in such a situation.

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A reactor is declared sufficiently safe when this safety study demonstrates that there would be no failure of the system in a sequence of hypothetical accidents. The problem with the method is that it treats the most common incidents the same way it treats rare incidents.

The second method employed for risk assessment, i.e. the probabilistic method, is based on facts about the level of risk that people or government are willing to take. There are nuclear regulatory bodies that set standards for the construction and operation of nuclear power plants. There have been very few accidents in nuclear power plants, so it is very difficult to quantify the risks based on experience.

Most nuclear power plants in operation today use the deterministic method to determine their safety standards. It could be complemented by the probabilistic method of risk-based regulations.

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The countermeasures to avoid any catastrophe depend on the type of known threats prevailing in the region. No control system could be designed for problems that have never occurred or are very unlikely to occur.