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Controversial Power Plant: Small Modular Reactors - F. Yaren Öztürk


It was possible to talk about the footsteps of the climate crisis twenty years ago, but today it is not possible to ignore the climate changes brought by the climate crisis. Governments make various decisions about the minimize the use of fossil fuels such as oil, natural gas, and coal to reduce carbon emissions, which is one of the leading causes of climate change. On the other side, some people acknowledge that wind, solar and other renewable energy sources may not be sufficient in this struggle. With the emergence of disagreements, there is an increase in nuclear power and next-generation small modular reactors, which is a controversial issue.


Small modular reactors (SMRs) are specially developed mini-reactors that can produce 300 MW per unit, approximately one-third of the generating capacity of conventional nuclear reactors. Since the early 1950s, they have been used to produce energy safely in a small area for ships and submarines in the US Navy. Due to the accident in Three Mile Island in 1979 and the Chernobyl disaster in 1985, its using status has been severely reduced with the various restrictions. Unlike wind and solar energy, nuclear energy is not affected by weather conditions to produce energy. It has a minimal carbon footprint, unlike gas and coal. Nuclear power is a stronghold in clean energy generation. To increase the reuse of SMRs, minimization of risks, improvement of potential problems, scalability and cost reduction are essential points.


Small modular reactors also utilize nuclear fission for heat and power generation like conventional nuclear reactors. Compared to the size of these power reactors, they are smaller in size and can be installed in places where access to nuclear energy is problematic. Compared to wind farms and solar power plants, SMRs cover less space. It is possible to produce a large proportion of the components that build the reactors at the factory. It can be sent in components for assembly at the place of delivery. With these features, it is aimed to reduce the cost and construction time compared to large-scale power generation plants. Some SMR models in the process of development have water as the coolant, while some designs have molten salt and metals as the coolant. SMR designs have a more straightforward structure compared to conventional reactors. The safety concept is mostly based on the intrinsic safety features of the reactor, such as operating pressure and low power, and passive systems. Passive systems have an advantage: In case of an emergency situation, there is no need for human intervention or any power to shut down the systems, owing to physical events such as convection, self-pressurization and natural circulation to which passive systems are connected. The possibility of releasing radioactive materials to the environment has been significantly reduced with increased security measures. Moreover, there are studies on new types of fuel and backup emergency systems that are carried out to reduce possible risks in SMR designs.


The UN report published in August 2021 emphasises that nuclear energy is essential to reduce climate change and achieve sustainability goals. Also, the importance of the role of small modular reactors is highlighted. More than 70 SMRs are currently being designed and developed in 18 countries. The world's first floating nuclear power plant started operating in Russia in May 2020, and power generation is provided from two 35 MW SMRs. China aims to launch studies on the SMR built on the island of Hainan in 2026. Romania aims to introduce SMRs by 2028 and drastically reduce coal use in the country by 2032. Rolls Royce plans to operate the first power plant in the UK in 2030. It is aimed that the UK will gain energy independence and become one of the significant producers of nuclear energy technology with the SMRs to be produced by Rolls Royce. In the USA, SMR, the Natrium reactor project of TerraPower company founded by Bill Gates, plans to operate in Wyoming, the most coal-producing state. At the same time, there are various studies about SMRs in progress in countries such as Canada, South Korea and Argentina.


Even though SMRs continue to be developed and invested worldwide, some people are hesitant and critical of nuclear energy. It is accurate that SMRs are easier and cheaper to build than regular nuclear reactors, but there is no evidence that they can be more affordable than installing a wind turbine or solar panel. People are afraid that funding for SMRs is putting investments in renewable energy at risk and fear that the main focus is shifting from renewable energy to nuclear energy. The safety of SMRs is also a topic of discussion. There is no consensus on storing the radioactive nuclear waste to be produced and overcoming the jeopardies that may arise in an emergency. There is also criticism that the increased number of reactors means an increased possibility of countries developing nuclear weapons.


While governments continue to try to significantly reduce their greenhouse gas emissions to reach the net-zero target by 2050, the requirement for affordable and safe low-carbon energy sources is increasing day by day. Nuclear power is a noteworthy low-carbon technology, albeit a controversial issue. Nuclear power is not entirely risk-free, but all energy sources have advantages and disadvantages peculiar to themselves. It is a fact that it is impossible to provide all energy in today's world only from renewable energy sources. At this point, SMRs that can regularly generate nuclear power can be a complementary part of renewable energy generation.