The potentials and challenges of a new nuclear era

As climate change became one of the most burning issues for our Planet, countries had to face the ugly truth of energy transition and the many challenges ahead. From the need for reliable green technology manufacturing capacity, balanced state subsidies in the midst of growing international competition, less complex policy and legal framework for installations to proper grid systems, they all add up to the same question at the end of the day. How is the energy mix of the future going to look like? Now that the U.S. Nuclear Regulatory Commission certified the design of NuScale’s small nuclear reactor, it is worth looking into the technology’s potential and challenges. Is nuclear necessary for the energy transition? Are SMRs offer a solution to security problems? What do they mean for the rest of the world?

We need nuclear

First and foremost, it is vital to emphasize that we need nuclear power for the energy transition. As noted by Fatih Birol, the executive director of the International Energy Agency (IEA),  back in 2019 “nuclear can make a significant contribution to achieving sustainable energy goals and enhancing energy security”. The same report highlighted that nuclear power was the second-largest source of low-carbon electricity in 2018, with 452 operating reactors providing 10% of the global electricity supply. Although nuclear has been losing ground in developed countries, mainly because of environmental and security concerns, the exact opposite has been going on in emerging economies, like China, India, and Russia, which are responsible for the majority of 60 nuclear power plants currently under construction. That said, with the war in Ukraine and rising energy prices a new momentum is building up for nuclear power. The fact that we need nuclear was once again repeated by another IEA report from 2022, stating that “building sustainable and clean energy systems will be harder, riskier and more expensive without nuclear”. The document highlighted that around 60% of today’s nuclear power capacity derives from plants that are more than 30 years old and were designed and built in the 1970s. Not to mention that western countries have lost market leadership and as a result, 27 out of 31 reactors that started construction since 2017 are Russian or Chinese designs. Still, nuclear is a reliable and low-emission energy source. As noted by the U.S. Energy Information Administration, nuclear power plants in the U.S. were producing maximum power more than 92% of the time in 2021, compared to solar (24.4%) or hydro (36%) for instance. That said, mild winters and summer droughts, just like in 2022, could lead to lower hydropower and cooling capacity for nuclear power plants. As for emissions, while nuclear electricity generation does not produce GHG emissions, its life cycle GHG intensity is around 34-60 gCO2e/kWh, which is a fraction of coal’s 1,001 gCO2e/kWh.

Despite clear benefits, having nuclear is easier said than done. A study from 2021 highlighted  long research, licensing, planning (around 5000 hours of staff time), and construction times (on average between 7.7 and 10 years) as the main limitations of nuclear expansion, besides drawbacks such as the risk of catastrophic accidents, proliferation, and radioactive waste. Let alone the huge amount of capital required for the whole process, which tends to be 2 to 3 times higher than planned.  With the dawn of small modular reactors (SMRs) in the commercial sector, this might change for the better.  

What are SMRs?

The Idaho National Laboratory defines small modular reactors (SMR) as “a nuclear fission reactor that features factory-built-and-assembled modules in a variety of configurations and electricity outputs”. They are about 1/10 to ¼ the size of traditional nuclear power plants, which makes their construction cheaper and faster. On the flip side, they generate less than 300 megawatts of electric power compared to a traditional reactor, which can do approximately three times this amount. They can be customized for different locations; the modules can be assembled in a factory and can be used for power generation, process heat, desalination, or other industrial applications. This versatility in terms of energy usage is crucial. One of their most important advantages, however, is adaptability, as they can complement other clean energy sources such as solar, hydro, or wind to ensure their continuous availability. Thus, SMRs provide solutions for some of the main disadvantages of nuclear, namely time and money. However, that still leaves us with three other obstacles that are at the core of the public anti-nuclear agenda.

Nuclear waste:  

First of all, it is vital to mention that only 3% of the total volume of nuclear waste has 95% radioactivity, thus considered high-level waste. However, storing that small amount, for thousands of years if needed, must be a top priority. According to the latest research, using deep geological repositories (DGRs), which is also the currently preferred way, is the most ideal solution for long-term storage. That said, as the study pointed out, we must make sure that the waste is stored in a retrievable form so that it can be recycled later, which is the best long-term option. With new technologies on the horizon, such as transmutation, which could not only drastically reduce the amount but also the necessity to store it from 300,000 to 300 years, nuclear waste might cease to be an issue in the near future. As for SMRs, a recent study that looked at three designs, out of dozens, concluded that their waste is “unsuitable for direct geologic disposal”, thus it must be treated, conditioned, and appropriately packaged before it, which will introduce significant costs and radiation exposures.


In general, there is not much information on the proliferation risk of SMRs, because most of them are in the design phase. A study from 2015 looked at generic fast SMRs with a core lifetime of 30 years and an electric output of 10MW. It found that “(they) produce significant quantities of plutonium attractive for weapon purposes”. The paper also mentioned mitigating factors like a sealed core “that enables easy detection of unauthorized access” and could act as a deterrence, which is not worth much in case the state itself decides to use it for weapon purposes. This is supported by another paper from 2018, which concluded that “ (…) both the SMR and LWR scenarios to be more proliferation-resistant than the fast reactor scenario”. That said, the study noted that SMR design characteristics such as a long-lived core, the lack of onsite fresh fuel, and the lack of requirement for reprocessing fuel can potentially enhance proliferation resistance. Another factor to consider is the reprocessing facility for the spent fuel. Would there be an internationally owned one? Or would it be solved domestically? If SMRs ever became more widespread, it is safe to assume that countries would opt to have domestic facilities, which must be properly guarded then, to reduce transportation and related costs. However, that would enable several actors with access to a key technology in acquiring nuclear weapons.

Catastrophic accidents:

When it comes to safety issues, death rates from radiation are incredibly low and even if we count the major nuclear accidents, health issues rather arise from post-traumatic syndrome and depression associated with the evacuation measures. If we compare the death rates per unit of electricity production per energy source, according to various sources summarized by Our World in Data, nuclear is the second safest energy source after solar. According to this, while coal causes 24.62 deaths/ Twh, nuclear is responsible for 0.03 deaths/Twh. Indeed, as a study from 2021 notes, fossil fuel pollution killed more than 8 million people in 2018. When it comes to SMRs, their small size simplifies hardened facility defense, some models can even be underground and as they contain substantially smaller radioactive inventory, they are easier to cool down and the contamination scale of any major incident is drastically limited. That said, catastrophic events cannot be ruled out entirely.

Looking ahead

It is only a matter of time before small nuclear reactors make their way into the civilian sphere. After all, the U.S. Navy has been using them to power some of its vessels for sixty years, starting with the first nuclear-powered submarine, USS Nautilus, which was commissioned in 1955. Today all submarines and aircraft carriers are powered by nuclear propulsion in the U.S. Navy. As highlighted by a Forbes article from 2019, this “Nuclear Navy” logged more than “5400 reactor years of accident-free operations”, under which it traveled 130 million miles, enough to circle our planet 3500 times. And as the latest report, conducted by the Naval Nuclear Propulsion Program and the U.S. Environmental Protection Agency concluded, these nuclear-powered ships and support facilities had no discernible effect on the environment.  

Understandably, there is also a growing interest from both governments and private entities considering that the global SMR market is expected to be worth between $150 and $300 billion by 2040.  For instance, the U.S. Energy Department said it provided more than $600 million since 2014 to support domestic small reactor concepts. What is more, as noted by Financial Times, new federal legislations enacted in the last one and a half years will lead to around $40 billion in investments in the upcoming decade.  The UK is also eyeing to secure its energy supply with a fleet of SMRs, with the construction beginning in 2028. The government-backed Rolls-Royce’s SMR design with £210 million in government funds in 2021. It is currently in the approval process, with a result expected in mid-2024. Canada launched its Small Modular Reactor Action Plan in 2022 and deemed SMRs as the future of its nuclear industry. Let alone China, which was the first to connect an onshore SMR to its grid in 2021. Beijing also wants to capitalize on its advantage by exporting this technology to members of its Belt and Road Initiative. And finally, Russia was the first country to commercially operate  Akademik Lomonosov, a floating nuclear power plant, in 2020. Now both Kyrgyzstan and Myanmar are looking for Russia to supply SMR plants to secure their energy needs nationwide.

The growing interest in this technology, especially from developing countries, also leads us to another question: Can SMRs democratize nuclear power? Shortly, not in the near future. The fact is that nuclear is not only about numbers like economics and efficiency, but has strong underlying socio-political angles which have a lot to do with the three problems mentioned above.  As a paper on the expansion of nuclear power from 2018 noted, it is vital to assess the safety culture of so-called “newcomer” countries. The study explains that traits of weak security culture include: lack of rigorous operator training and skill improvement; absence of “questioning attitude”; fear about raising safety and security concerns; unstable politics which prevents proper nuclear power plant management; lack of bottom-up information recognition; a weak national nuclear regulatory agency that is not independent of politics and widespread corruption which can undermine safe activities. If one takes a step back from the national level, one might stumble upon even more questions. From issues related to cross border license, liability and regulatory challenges to the lack of an international safety regime which is strong enough to set safety standards, provide expert services and act as a regulator.


This article looked at data and research concerning the potentials and challenges of current SMR designs, with the aim to start a wider discourse on this technology and to address problems deriving from current plans. Though a smaller SMR reactor could cost anywhere between $150 million to $500 million, as production becomes more streamlined the prices will decrease accordingly. With more state subsidies and private capital allocated to research and development projects, the technology will be better, safer, and probably more widely accepted by the public. Though the future will not be entirely nuclear, it has a place in a more sustainable future to provide consistent and reliable energy and to fill the gaps that renewables could not, especially in remote areas.  Whether it is only to recharge ships around the Arctic or heavy-duty electric vehicles, it has potential that must be utilized. That said, nuclear is something we should not trifle with and that is why we need responsible governments and strong international institutions. Sooner than later, choices will have to be made regarding the designs. They must not only be economically viable but also have to consider such important factors as fuel, design, storage plans, and their overall risk of proliferation. All while creating a multinational entity that lays down the regulatory framework of SMRs and has enough power to intervene if needed. Unfortunately, because of diverging national and geopolitical interests, it is highly unlikely to happen in the near future.