Interview with Carlos Vázquez-Rodríguez, PhD Researcher at Forschungszentrum Jülich, Germany and Member of Jóvenes Nucleares.
What is fission energy and what advantages does it have over other energy sources?
Let’s start with a common saying: Energy is neither created nor destroyed, it is transformed. There are different ways of transforming energy into https://www.fz-juelich.de/enelectrical energy, for example by transforming wind speed or the radiation that reaches us from the sun. We also have several “machines” that transform heat into electrical energy. A nuclear reactor, for example, is a “machine” capable of controlling a fission reaction (whereby the nucleus of an atom is split in two), in which an enormous amount of heat is released, and converting this heat into electrical energy.
Heat can be generated by burning fossil fuels, burning biomass, or using nuclear fission. The concept of energy density, i.e., the amount of energy we can extract, is very useful in understanding the differences between nuclear fission and other ways of generating heat.
Nuclear fission has a much higher energy density than all the others. We can extract much more energy through nuclear fission than, for example, the burning of fossil fuels. How much more? Well one pellet of nuclear fuel, which is the size of a finger, contains as much energy as a ton of coal. By analyzing the high amount of energy released by a nuclear fission reaction, we can understand many of the advantages of this technology.
In the case of Spain, for example, only 7 GW of the almost 120 GW of installed power correspond to nuclear energy. Well, with this limited percentage (less than 6%), and thanks to its ability to generate electricity for more than 90% of the year’s hours, nuclear power plants have been producing 20% of the country’s electricity for more than 10 years. The ability to produce continuously is the great advantage of nuclear energy over renewable energies, which depend on weather conditions. For the sake of illustration, wind energy generates similar amounts of electrical energy with almost 30 GW installed, 25% of the total power.
Another advantage of nuclear fission, which it shares with renewables, is that it is a clean process in the sense that it does not produce greenhouse gases, which are responsible for climate change. These technologies are undoubtedly the ones that should replace coal and fossil gas in our system.
Finally, another great advantage of nuclear energy over fossil fuels lies in energy security, a term that has been on everyone’s lips for months. Thanks to the enormous energy density of nuclear fission, it would be feasible to store fuel without depending on any external country. In fact, we could store nuclear fuel for twenty years of operation of all our nuclear power plants in the space of a soccer field. This is neither technically nor economically feasible with fossil fuels such as coal, gas, or oil. Hence the current energy crisis. Being much less energy dense, we cannot store enough of these fuels to cover our needs, which necessitates continuous purchasing and importing of fossil fuels.
Despite all these advantages, nuclear energy has a reputation for being unsafe and generating hazardous waste. How dangerous are nuclear power plants?
Nuclear energy, given its energy density and the fact that it has so much controlled energy concentrated in such a small space, has obvious potential risks. Obviously, these potential risks must be controlled, and undoubtedly, the public, and even more so us technicians, must demand the highest safety standards from the nuclear industry.
As a technician who is very demanding with the safety standards of our plants, proof of which is that I have decided to dedicate my life to studying them, I can confirm that our nuclear power plants meet the highest safety standards we should require of them. In fact, Spanish nuclear power plants are repeatedly placed among the highest rankings of the safest nuclear power plants in the world.
It is difficult to develop in so short a space an adequate justification for what I have just said, but it is important to put the “problem” of safety in perspective. What is the health impact of the alternative to assuming the potential risks of nuclear energy? Well, the air pollution associated with the use of fossil fuels causes several million deaths each year, according to the World Health Organization.
We are not aware of the abrupt and radical change we need to achieve if we are to do without fossil fuels, from which we get 90% of the energy we consume. This will be an even greater challenge if we are to get rid of fossil fuels without nuclear energy. We need all clean sources of energy generation; we cannot do without any of them.
What waste does a nuclear power plant have and how is it managed?
90% of the waste produced by a nuclear power plant is very similar, in terms of radiotoxicity, to that generated by a hospital, industrial facilities, or other radioactive elements that are present in our daily lives. They are not a cause for concern. The complex management is for the remaining 10%, the high-level waste. This is basically spent fuel from nuclear power plants. This type of fuel has two major problems. On the one hand, it is highly radiotoxic, so it must be well confined and controlled. On the other hand, its radiotoxicity lasts for tens of thousands of years, so this waste must be managed in the very long term.
However, this waste will cease to be radioactive at some point, unlike other toxic wastes produced in various chemical industrial processes, which will never cease to be radioactive. What’s more, the volume of this waste is tiny, much smaller than that of these other toxic wastes. So much energy is extracted with such a small amount of fuel (again highlighting the importance of energy density) that the amount of remaining waste is minimal. If we take Spain, for example, the high-level waste generated by all of the country’s nuclear power plants over the more than 40 years they have been in operation would fit into five Olympic-size swimming pools.
Therefore, in terms of volume, they are not a problem, nor is their management, since the technologies we need to control and manage these wastes exist.
Today, the big problem in waste management is the inability to reach social and political consensus when deciding on an optimal waste management strategy. This is not the case in some countries such as Sweden or Finland, which have more advanced citizen participation processes than in other countries such as Spain. A definitive solution, called deep geological storage, is already under construction there. Technicians have determined that these territories are geologically optimal for the construction of definitive storage facilities because they can ensure that they will be completely protected from any layer of the biosphere for tens of thousands of years.
If there is one thing that both nuclear and anti-nuclear scientists should agree on, it is that the waste that has already been produced must be managed safely and appropriately. This lack of consensus is the main barrier to implementing a definitive solution; it is neither a technical nor an economic problem, as the European Commission acknowledged in the report that gave rise to the inclusion of nuclear energy as a transitional technology in the Green Taxonomy.
What are the main challenges facing nuclear power and how are they being addressed?
One of the main challenges, especially in the West, is to meet the construction deadlines for new nuclear reactors. The last few projects that have been built have had long delays, resulting in huge cost overruns. On average, or median to be more precise, the construction time for a reactor is between seven and eight years. However, in the West there are some that have taken up to 15 years to build while in countries like China they take six years, meeting all safety standards. The same is true in South Korea. Therefore, construction delays are not an intrinsic issue of technology, and the big challenge for the West is to complete projects on time and within budget.
One of the other great challenges facing nuclear energy is the “bad” reputation that you mentioned in an earlier question. However, if we objectively assess nuclear energy, we can see that it has all the characteristics that we would be looking for in a new energy to carry out the energy transition (clean, continuous energy, and with high energy density). If it were not for all that heavy “baggage”, that bad reputation and social opposition in certain countries, all the investors in the world would be wagering everything to solve the main challenge of nuclear energy, namely, reducing its costs. They have been doing this for almost 30 years for solar and wind power, which, although too expensive in the past, are now the most competitive thanks to the continued investment in them.
This is why the other great challenge for nuclear energy is communication, education, talking and interacting directly with the general public and politicians to highlight our capabilities and show how useful and essential nuclear energy is in the fight against climate change.
Luckily, we are seeing an international trend that is taking us in that direction. There are many countries that are starting to invest very seriously in nuclear energy and there has been a clear shift in this trend over the last five years or so. France, for example, is planning to build between eight and fourteen reactors over the next fifteen years. The United Kingdom has two reactors under construction and has just approved the construction of two more. The United States has six or seven very advanced modular reactor projects. China, India and Russia have had ambitious active nuclear plans for decades. We see policy changes in South Korea, Japan, the Netherlands, Sweden, and Poland. All in all, virtually every major economy in the world is talking about building new reactors or extending the life of existing ones.
Are the reactors being built today very different from those built 50 or 60 years ago? Has the technology evolved a lot?
It’s very impressive. I like to call it the nuclear power of the 21st century.
Today’s designs are designed to overcome the challenges of conventional reactors that we have been talking about during this interview. For example, today’s nuclear power plants generally always operate at maximum power, and in the coming years they will need to be made more versatile. In the case of Spain, for example, we will be able to produce virtually all our electricity with solar energy in the middle of the day during the summer. That is why we will need nuclear power plants to adapt. The new reactors are designed for this.
On the other hand, the energy transition is not just about electricity. We need to decarbonize each and every process we do. And in heat production, for homes and for industries, we have an even bigger challenge than electricity. There are many sectors that are much more difficult to decarbonize than electricity. The new reactors are designed for this.
Reactors are being designed to produce hydrogen. China already operates reactors to produce heat for industrial processes such as steel production or other processes that emit a lot of CO2. Work is also being done on reactors to desalinate water in places where there is no potable water or on transportable reactors to bring electricity to remote places that do not have established power grids, which Russia has already achieved in Siberia with its famous floating reactor.
There are even reactors at advanced stages of development designed to reduce radioactive waste management times from tens of thousands of years to just a few hundred! Not only that, this process, referred to as transmutation, can generate more fuel than is consumed. In practice, this would make nuclear energy a renewable energy, which is why it is attracting such high-profile investors as Bill Gates.
Ultimately, technological advances in nuclear energy have the potential to provide solutions to many of the major challenges of the energy transition.
What role should nuclear energy have in the international energy mix in the future?
Renewable technologies should lead the way in the energy transition. They have to be the protagonists of the changes we have to make in the way we generate and consume energy. But nuclear energy also has a role to play. There is no doubt about it.
Renewable energies need some kind of support, at least for the next 30 or 40 years or until there is a technology disruption that allows us to produce energy continuously, without depending on climate conditions, or to efficiently store the huge amounts of energy we consume on a daily basis. And this support must be provided by nuclear technology.
Achieving decarbonization by 2050 is key to the future of the planet. The challenge of meeting our emissions reduction targets is so great that it would be unwise to ignore any of the low-carbon technologies available to us. For more than 40 years, nuclear has been generating a high percentage of the planet’s clean energy, and it must continue to do so.
Comments on this publication