SMR Reactors – The Rising Future of Nuclear Power?

Nuclear power has remained a cornerstone of Finland’s energy production also in the 2020s. Although investments in it have not always received unanimous support, its undeniable advantage is that the electricity produced with nuclear power does not generate any carbon dioxide emissions in the production process.

The production of nuclear power is based on the release of binding energy from atomic nuclei in controlled fission reactions, which means that the amount of energy contained in nuclear fuel is extremely high compared to conventional fuels. This makes nuclear power a highly profitable source of electricity production in relative terms.

Modern nuclear power plants are large facilities that serve a significant share of the Finnish population and the country’s industry at the same time. Disruptions in production are immediately reflected in the price of electricity and in electricity bills, and in the worst case in the adequacy of electricity supply.

Advances in technology have also made it possible to develop small-scale SMR plants (Small Modular Reactor). With them, it would be possible to locate nuclear power directly near population centers or industrial facilities. 

New technologies easily raise questions: what benefits does the technology provide, and are there any risks involved? A generic description of expert perspectives and assessments is presented in this section.

Professor Juhani Hyvärinen, what are SMR plants?

“An SMR reactor is significantly smaller in size than traditional nuclear power plants. Their operating principle is based on the same reactions as the currently used light-water reactors, such as the nuclear power plants in Olkiluoto and Loviisa. The reactors produce heat in the same way through a fission reaction, and the resulting reaction heat is converted into electricity or used directly in industrial processes.

However, SMR plants are designed to be modular, which enables serial production, reduces logistical challenges, and facilitates their deployment and installation. The reactors can then be sized for different applications to meet specific needs. Their safety is also better than that of traditional plants, as the reaction can in practice be stopped immediately if a disturbance occurs, and a small reactor is easier to cool than a large one.

In general, SMRs can produce heat from a few tens of megawatts (MW) up to about 1,000 MW. For comparison, Olkiluoto 3’s thermal power is 4,300 MW, its maximum electricity production capacity is about 1,600 MW, and Finland’s all-time peak consumption has been around 15,000 MW.”

What can an SMR plant be used for?

“SMR plants are suitable for various industrial energy needs, especially in processes where energy is required around the clock. Reactors can equally be located close to other processes, in which case SMR reactors provide them with a low-emission solution that stabilises operational reliability and reduces the processes’ dependence on the local electricity grid.

Because SMR reactors are capable of flexible power adjustment and some can also store energy, they can be used, among other things, to strengthen overall security of supply. Naturally, reactors can be used to produce electricity for all kinds of needs, including private use, but the utilisation of small reactors in district heating systems has also been considered. In that case, the heating system would no longer depend on combustion, especially of natural gas or coal, and heating would be as clean as electricity.”

Are SMR plants safe?

“SMR reactors can be advocated specifically because of their safe and easily controllable process. The amount of radioactive material contained in a reactor is smaller the lower the reactor’s thermal power is. Many SMRs use simplified safety solutions whose operation is more reliable than complex systems, which reduces the risks associated with nuclear power. The small size and modularity of the reactors make it possible to place them underground, which provides natural protection, for example, against natural disasters. Underground they would withstand even extreme threats, such as acts of terrorism and military attacks. In this way, they are safer compared to, for example, current large nuclear power plants.

In small reactors, the fuel is also replaced less frequently, which increases the reliability of energy production and minimises risks related to disturbances. When determining the size of the reactors and choosing their location, it is ensured that under no circumstances can people in the surrounding area be exposed to radiation exceeding the limits assessed as safe.”