Nuclear fission: early, seductive fruit of a scientific revolution
The history of technology shows that nuclear power for energy supply is a hopelessly out-dated technology / Episode 1
Nuclear energy is a technology that is far inferior to new options for energy supply, not only in practical and current terms but also in principle and in the long run. I believe this is a compelling conclusion from the history of science and technology, which I will review here in a twelve-part series. First, we will look at the preconditions for and the history of nuclear energy, then at the profound new findings and developments since the discovery of atomic fission, and finally at the resulting options.
(This is a computer-aided translation by the author from the German original)
Everyone is talking about nuclear energy again. In most countries, it was already considered to have been phased out. Thirty years ago, it had passed its peak. Reactor accidents that narrowly missed an almost unimaginable catastrophe, protest movements and continuing cost increases caused a rethinking. In recent years, above all, China has ensured that the total number of nuclear power plants has remained more or less the same by building new reactors. Still, their share in global electricity production has decreased significantly. Against the backdrop of global warming caused by fossil fuels, rising costs for developing new oil sources and, most recently, the gas crisis in Europe, many people who previously rejected nuclear energy have now become uncertain. We have a solution to our energy problems that is not entirely unproblematic but relatively practicable in comparison; one hears more and more often. The loudest proponents sometimes may be driven by tangible industrial interests, military strategies, or party-political opportunism. Still, above all, in my opinion, the new debate shows a short historical memory and a lack of understanding of the fundamental scientific and technological developments since the beginning of the last century. A frightening ignorance, even among important decision-makers, of the scientific findings and technologies on which our high-tech civilisation is based. Of developments that have made it possible in the first place for eight billion people to live in growing prosperity on our planet today - three times as many as in 1950 and five times as many as in 1900.
On the difficulty of maintaining an overview
Building on the revolution of our world view through physics and chemistry since 1900, there have been further upheavals in natural science and technology since the discovery of nuclear fission, which have opened entirely new possibilities - including for energy supply. Their scope is often still not fully understood. Against the background of these alternatives, which were only developed later, nuclear energy has proved to be an unnecessarily risky, expensive, and cumbersome technology, which is not only currently inferior to new options, but also inferior to them in principle.
To understand this, it is helpful to review the history of science and technology since the beginning of the last century. The advance into the nano-dimension of molecules, atoms, and atomic nuclei, in which different laws apply than in our familiar macro-world, opens a new chapter in the evolution of life on earth. Until the end of the Second World War, the focus was on the interrelations between energy and matter, after which also information increasingly entered the attention of science and technology.
While there are many good accounts of science's history in the last century's first half, there seems to be a lack of summary accounts of developments since World War II. The explosion of knowledge has produced sectoral reports in various disciplines, but an overall view is hard to reach. This makes it increasingly difficult to assess a specific technology in its context - all the more so for laypersons who, as citizens or politicians, want to help decide where the journey is headed.
Even for natural scientists and technologists, it is becoming more and more challenging to keep track of things; most of them argue only from the perspective of their particular field. Back in the 1980s, I was startled to discover that the generation of that time comprised 80% of all scientists who had ever lived up to that point - that has hardly changed to this day. The number of new scientific publications worldwide has grown by more than 5% every year since 1952, i.e. it is more than thirty times higher today. In the physical-technical disciplines, growth has been even faster. It is, therefore, most important that all those who discuss or help to decide on the social use of technology should take an overview from time to time and not lose sight of the historical context. Decision-making mechanisms must also adapt to the ever-faster pace of development. Just a few years ago, I saw high-ranking energy managers arguing with conviction based on cost ratios that were three or four years old - in the world of coal and nuclear power, this could be done without hesitation for a long time, but when the cost of photovoltaics was halved in four years, they were suddenly entirely off the mark with their conclusions.
In the discussion about the use of technologies, economic interests, political strategies, ideological definitions, the persistence of old industries, job arguments, and consumer habits often play a more critical role than fundamental technical-scientific, economic or socio-political arguments. Often, it is only decades later that those involved realise that they had paid too little attention to the technical-economic "fundamentals", which can perhaps be glossed over in the short term but will prevail in the long term. Political professionals, financial specialists, business economists and lawyers, who dominate strategic decision-making bodies, are particularly susceptible to this and tend to think in the short term. That is why in this series, I would like to emphasise the fundamental scientific and technical developments that can serve as a basis for assessing the long-term opportunities of one strategy or another. Sitting back and waiting to see how the game of economic and political forces plays out is no longer justifiable. This year at the latest, the threatening consequences of earlier wrong decisions in energy policy have become apparent to most people. The climate clock is ticking.
From the discovery of radioactivity to nuclear fission: physics revolutionises the understanding of energy and matter
The story of nuclear energy has been told many times, and it has fascinated generations of physicists, technicians and politicians - not least because of the destructive power of nuclear fission, which is hard to imagine. Many facts are widely known, not controversial, and can be read easily (e.g., in Wikipedia). I give individual source references only where one would have to do more in-depth research.
At the beginning of the last century, physics developed with breathtaking speed and changed the understanding of the material world so fundamentally that the scope of the new view is still difficult to grasp today. At the turn of the century, people were not yet convinced of the existence of atoms. With the discovery of nuclear fission in 1938, hope arose for a new, almost inexhaustible energy source.Â
In 1896, Antoine Henri Becquerel discovered strange radiation emitted by the heavy metal uranium. Marie and Pierre Curie subsequently discovered other radioactive elements and named the radiation "radioactivity." Ernest Rutherford discovered that there are several types of radiation and explained them in 1902 by the fact that they are produced when radioactive atoms decay into smaller atoms. In 1911 he revolutionised the understanding of matter with his atomic model: new experimental results could only be interpreted in such a way that the mass in the atom is not evenly distributed but concentrated in a tiny positively charged atomic nucleus, which is orbited by almost massless negatively charged electrons. Â
At the same time, progress was made in understanding radiation: To explain experimental results in the investigation of thermal radiation, Max Planck hypothesised in 1900 that electromagnetic radiation energy is portioned into so-called quanta. Building on this, Albert Einstein succeeded in 1904 in explaining the photoelectric effect and establishing the Special Theory of Relativity. In it, he postulated the equivalency of mass and energy with the famous formula E=mc2. In 1924, Louis de Broglie put forward the thesis that not only photons but also particles with mass can be described as waves. Between 1926 and 1928, Erwin Schrödinger, Werner Heisenberg and finally Paul Dirac succeeded in finding a mathematical formulation of quantum theory that also included Einstein's Special Theory of Relativity. The circular orbits of the electrons around the atomic nucleus in the previous atomic model could only be understood as clouds of residence probabilities. Wave and corpuscle were only different descriptions of the same. The dynamics in the atomic world could only be described mathematically and were not accessible to human perception. Â
However, the composition of atomic nuclei and various radioactive radiation phenomena remained mysterious until 1932, when James Chadwick proved the existence of neutrons. Thus, the explanation of atoms, atomic nuclei and the periodic table of the elements was complete for the time being: Atomic nuclei consisted of protons and neutrons of approximately equal weight. Slightly lower masses of large atomic nuclei compared to the sum of their components could be explained by the equivalence of mass and energy and became an indicator of their stability. Large atomic nuclei contained a slightly higher proportion of neutrons than smaller ones. In 1934, Irène and Frédéric Joliot-Curie succeeded in transforming atomic nuclei by irradiation and producing new elements and isotopes.
Thus, the theoretical and experimental prerequisites for discovering nuclear fission were essentially given. As early as 1933, Leó Szillárd in London had the idea of generating energy through nuclear chain reactions - he had a corresponding patent kept secret because of its possible military significance. Nuclear fission was then experimentally discovered in Berlin in 1938 by the chemists Otto Hahn and Fritz Strassmann and shortly afterwards explained by the physicists Lise Meitner and Otto Frisch. Meitner, who had worked closely with Hahn, had fled from Germany to Sweden shortly before. Hahn and Strassmann split the atomic nucleus of the uranium isotope 235 by bombarding it with slow neutrons, releasing radiation of various kinds – Including fast neutrons – In addition to a cascade of fission products with different lifetimes. This led to the expectation that a chain reaction of uranium fission could be triggered by deliberately slowing down the resulting neutrons.
The end of a scientific era
This ended a period of intensive international cooperation between researchers in Berlin, Paris, London/Cambridge, Rome and Copenhagen that fundamentally changed the understanding of matter and energy and opened up access to the world of atoms and molecules. In this world, which is no longer measured in micrometres but in nanometres, completely different laws prevail than those we know in our macro-world, which we can see with our own eyes. In these forty years or so, the world view of science has probably changed more profoundly than in the four hundred years since Copernicus. We are still struggling with the philosophical implications and the practical consequences for the role of humans in the ecosphere.
The First World War interrupted this work for a few years but could not stop scientific development, which from an economic point of view, was still insignificant. However, with the discovery of nuclear fission shortly before the Second World War, hopes arose that a new, almost inexhaustible energy source could be used for military purposes. The opposing warring parties started secret, mutually isolated development programmes.
Next Episode 2/12: Taming the Bomb: Unstoppable Rising Costs