Nuclear energy has been surrounded by controversy since its inception. The debate on its use to produce electricity has multiple points of view, which must be analyzed separately to obtain conclusions. It is probably in the purely scientific and technological aspects where there is a greater consensus on the need for its use, and an indication of this is that opinion polls carried out in various countries always reach the same conclusion: the higher the level of scientific knowledge of the respondent, the better their opinion of nuclear energy.
As in any matter related to science and technology, there are no blacks and whites. Nuclear energy is not the worst invention of humanity , but it is not the only solution to all its problems. Let’s analyze each of its controversial aspects from a purely scientific point of view and let the reader form their own opinion after contrasting them.
Climate change
The sectors of electricity, land transport and air conditioning are the largest sources of CO2 emissions of human origin, and at the same time they are the sectors that can most easily be decarbonized. Some of the industry, agriculture and air transport need a greater effort to be electrified . At least 80% of the world’s electricity would need to be low-carbon by 2050 to have a realistic chance of keeping warming within 2C above pre-industrial levels, according to the latest IPCC report.
In 2018, 64% of the world’s electricity was generated from the burning of fossil fuels , a modest decrease from 2008, when the figure was 67%. During the same period, the absolute production of electricity from fossil fuels increased by 25%. The scale of the challenge requires the growth of all available low-emission energy technologies. In this regard, and always according to the IPCC, the CO2 emissions of the complete life cycle (from mining to waste management) of nuclear energy are among the lowest of all forms of electricity generation, equivalent to emissions from wind power.
Nuclear power is a well- proven technology, it is available today and can be expanded rapidly, as France has done in the past or China is currently doing, making it an indispensable part of climate change mitigation tools. , along with all renewable energies with low emissions, as the International Energy Agency (IEA) repeats in all its reports.
Construction time
A common and justified criticism of nuclear energy is the delay in the construction of some reactors , especially in Europe. While it is true that both Flamanville 3 in France, Olkiluoto 3 in Finland, and Vogtle 3 and 4 in the US have suffered long delays, this is a clear case of the biased sample fallacy. Such delays are cited and an attempt is made to generalize worldwide. But the reality is quite different. There are currently 56 nuclear reactors being built (Olkiluoto 3 has already been completed) around the world and the absolute majority of them are being built in about 5-6 years.
What is the reason for the delays in the construction of some reactors? The construction of a nuclear power plant is a huge engineering work , which encompasses multiple technological aspects, from civil works to mechanics, electricity, electronics or information technology. When a new type of reactor is built, as is the case of the EPR (European Pressurized Reactor) in France and Finland, both the companies and their workers lack experience and it is very difficult to hit the deadlines and budgets. Similarly, when you have enough experience and workers go from one plant to another, the data shows that the implementation is much faster. This is what happened in France during its nuclear expansion in the 1970s and 1980s, and it is what is currently happening in Russia and China.
construction costs
According to the IEA’s Sustainable Development Scenario (SDS), it will be necessary to increase global nuclear capacity, in addition to implementing ambitious life extension programs for existing nuclear power plants. In 2019, nuclear power was not on track to reach the necessary output. In fact, the rate of annual power additions would need to at least double between 2020 and 2050 to meet the SDS targets.
There are many reasons for this deficit, but the most important are related to the high cost of new nuclear projects, particularly in countries that have not built nuclear power plants in recent decades. The perception that new nuclear power plants carry a high financial risk deters investors and has further reduced the ability of countries to attract financing for future projects.
These problems are not present in countries that have continuously built plants. With experienced project organizations and well-established supply chains, nuclear projects are delivered on budget and on schedule. The difficulties of many FOAK (First of a Kind) projects are not inherent in the nuclear technology itself, and it is the main cause of delays and cost overruns.
Capital costs represent more than 70% of the total costs of new nuclear power plants. These projects require large amounts of capital to be mobilized up front. Once construction is complete, operating costs are low and predictable.
Paradoxically, also according to the IEA, the cheapest way to produce electricity worldwide is the long-term operation of existing nuclear power plants, beyond the 40 years foreseen in the design. In the United States, Spain’s regulatory and technological benchmark, all its reactors have a license to operate for 60 years and several of them have already obtained permission to operate for 80 years, after exhaustively reviewing their safety.
nuclear safety
Human beings have a very biased perception of risks. We all fear sharks, which kill about 10 people every year. However, the animal that causes the most deaths and by far is the mosquito, due to its ease in transmitting diseases, with an annual balance of 725,000 deaths. Similarly, various studies conclude that nuclear power is an exceptionally safe way to produce electricity on an industrial scale . It is the energy that has caused the least number of deaths due to energy produced, 100 times less than hydroelectric energy, rightly considered clean energy and also very safe.
Serious nuclear accidents are very rare and not particularly dangerous. The Chernobyl accident that occurred in April 1986 is the only nuclear accident that has had quantifiable effects on people’s health: dozens of direct deaths and an estimated 4,000 based on the dose received. However, the March 2011 accident in Fukushima, Japan, did not cause any immediate health effects and is unlikely to cause future effects, according to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The same can be said of the Three Mile Island (TMI) accident, in 1979, in the United States, in which no radiation casualties were recorded thanks to the absence of significant radioactive releases.
The Chernobyl accident did not help improve safety in the rest of the reactors because their design was particularly unstable and unsafe (we refer to the tests) and lacked a containment building, in addition to the necessary safety culture. However, both TMI and Fukushima provided a tremendous source of operating experience that helped strengthen safety at other reactors around the world. After Fukushima, the FLEX (short for flexibility) strategy was implemented , incorporating autonomous and airborne portable equipment in helicopters, which allow the safe shutdown of the reactor in the event of accidents not foreseen in the design, as occurred in Japan in 2011. Although there is no absolute safety, we can say that nuclear power plants are safer than ever and that a hypothetical accident would have even fewer consequences.
However, public opinion continues to fear more for their lives in a hypothetical nuclear accident than in the possibility of being one of the 7 million people who lose their lives each year due to air pollution, from the burning of fossil fuels and biomass. , according to the WHO. Once again, the idea of disclosure prevails, the invitation to contrast the data from reliable sources and each one obtain their own conclusions.
radioactive waste
All forms of electricity generation produce some type of waste in one or more of the phases of their life cycles. They all require mining and initial processing of minerals, generating waste, some of which are toxic and radioactive. But, nuclear power is the only energy-producing industry that takes full responsibility for the management of all its waste, from the mine to final storage. Civil nuclear waste has been managed without significant environmental release for six decades worldwide. Unlike other toxic waste, such as heavy metals, the main hazard associated with nuclear waste, its radioactivity, decays over time .
It is common to say that the management of radioactive waste has no solution, or that this, if it exists, is not satisfactory. To put the volume of waste we are facing into context, according to the International Atomic Energy Agency, as of 2013 a total of 370,000 tonnes of fuel elements had been removed from commercial reactors around the world. With a simple and approximate calculation, we would obtain the volume of a cube with a side of 47 meters.
The fuel used is a ceramic solid insoluble in water and encapsulated in cladding before being stored in containers. It cannot explode like an atomic bomb due to its low enrichment (less than 4% of U-235, compared to the 90% needed for a bomb) and it does not generate enough heat to melt, as has happened with nuclear accidents, since the fuel takes time out of the reactor and generates much less heat.
The basic principle of radioactive waste management is not to pass on our responsibility to future generations . We have generated waste for our benefit and we are the ones who must provide a solution. The nuclear sector is responsible in all countries for managing the entire fuel cycle, paying for the entire process.
Global scientific consensus indicates that deep geological storage (DGS) is a safe and effective way to store long-lived, high-level radioactive waste to isolate it from people and the environment. The safety principles and technological solutions for the long-term management of radioactive waste are well established and their requirements have been independently reviewed by qualified international organizations. Indeed, the scientific and technological consensus on the safety of AGPs has developed over half a century, thanks to the work of multiple teams of scientists and engineers in laboratories in Belgium, Finland, France, Germany, Japan, Russia, Sweden, Switzerland and the United States. United States, in addition to other countries including Spain.
The accumulated scientific results, the technological evidence and the safety demonstrations have been reviewed by internationally recognized experts to reach the current level of maturity of this solution to radioactive waste. The strategy after the decommissioning of an AGP is based on passive security to isolate and contain the waste. This means that an AGP, once sealed, does not need supervision or maintenance, therefore, it will not have management costs. All investment must be made prior to sealing.
Another essential aspect in an AGP is geological stability. Sites that have been geologically stable for millions of years (1 billion in the case of Finland, the first AGP to be put into service) are selected to ensure that for thousands of years the waste will remain safe until it has the same level of radioactivity than the environment.
In addition, it is expected that the IV Generation reactors will be able to use about 99% of the energy of the new and used fuel (the current ones only use 5%), significantly reducing the volume of waste generated, essentially the fission products will remain . Currently, only one Generation IV reactor, the Russian BN-800, is in operation, although two more are under construction.
nuclear proliferation
The United Nations International Atomic Energy Agency (IAEA) Safeguards have proven to be effective arrangements and the nuclear power industry does not increase the risk of nuclear weapons proliferation. North Korea has developed these weapons, but has never generated nuclear electricity. More than 30 countries have commercial reactors and only eight of them have nuclear weapons. Nuclear weapons programs were developed first in most of these countries, and the decision to have nuclear weapons is not directly related to the readiness of a civilian nuclear program. While certain facilities (enrichment and reprocessing) can be used in weapons production, Safeguards are effective tools to monitor them. In fact, nuclear power plants can help eliminate nuclear warheads, as was the case with the Megatons to Megawatts program between 1993 and 2013, when Russian and US stockpiles equivalent to 20,000 atomic bombs were converted into nuclear fuel, which represented 19% of the world’s uranium needs and produced 10% of the electrical energy consumed in the US during the aforementioned 20 years.
Diversity of offer
All forms of low-carbon electricity generation will need to grow significantly if the world is to control anthropogenic greenhouse gas emissions. Renewable energies, in particular solar energy and wind energy, will play a very important role, but they will not be the complete solution . Energy policymakers should keep in mind that solar and wind power are variable power sources that require backup because they cannot guarantee power supply at all times.
Calculating the additional costs of integrating highly variable renewable electricity sources into an energy system is complicated. Some of the backup could come from storage, both in the form of batteries and pumped hydro plants. However, while they are necessary systems and will undoubtedly play an increasing role, they also have their limitations. We do not yet have mega-batteries with a huge capacity to support a large electrical network, we do not know how much they will cost, and pumping stations need a large amount of water, scarce in some countries, which evaporates and needs to be replenished, in addition to occupying large extensions of land. Also, it is important to point out that these storage systems would need a surplus of energy, which is not always produced unless the renewable generation system is extraordinarily oversized. In short, all these storage systems will be necessary, but not sufficient.
In many countries, nuclear energy is going to become an ideal complement to electricity systems with a high penetration of renewable energies, thanks to its low carbon dioxide emissions, its scalability, its constant supply capacity as a base, and its capacity to produce variable power. Some older reactors already have the capacity to make rapid load changes to adapt to the variability of renewables and all current Generation III reactors have this capacity. A completely decarbonized electricity mix is possible with an adequate combination, depending on the renewable resources of each country, of wind, solar, hydraulic, geothermal, storage and nuclear energy.
