The production of energy is a dangerous activity, a source of much damage and fatal accidents. When we compare the exploitation of different energy sources, it appears that the energy estimated as the most dangerous, nuclear, is not the one that causes the most deaths. In the past, in Western countries, the exploitation of coal in underground mines in particular when safety or social protection policies were not developed, caused many deaths. With technological and social progress, the risks have decreased but the risk has shifted to developing countries that operate coal mines and have a significant number of deaths.
A database maintained in Switzerland at the Paul Scherrer Institute, lists the number of accidents causing the direct death of at least 5 people between 1960 and 2000 during the exploitation of an energy source. Thus, the 3 main energy sources that caused the most deaths are :
Hydroelectricity, which had 11 accidents and caused the death of 29,938 people
Coal, with 1,221 accidents and the death of 25,107 people
Oil, with 397 accidents and the death of 20,218 people
The high mortality rate linked to the exploitation of hydropower is explained in particular by a single accident, the rupture of the Bangiao dam in China in 1975, which caused the death of approximately 26,000 people. By way of comparison, during this same period, the nuclear industry had one accident, Chernobyl, which caused the direct death of approximately thirty people, according to an official report.
Coal mine in Canada
The former high commissioner for atomic energy in France, Yves Berchet, states in an interview in 2019 with the magazine Le Point that nuclear power kills 1,700 times less per kilowatt-hour produced than coal, 350 times less than oil and 4 times less than solar or wind power. Two studies verify the ratios put forward by this specialist.
The first study, published in 2007 in the Lancet, indicates that direct deaths and cancers induced by nuclear energy could reach a maximum of 0.07 deaths per terawatt-hour produced, which is 350 times less than coal and 260 times less than oil. The second 2014 study published in Elsevier's Sustainable Materials and Technologies journal includes the Fukushima disaster.
According to this study, nuclear would account for 0.04 deaths per terawatt-hour produced, which is 2,500 times less than coal, 900 times less than oil, 600 times less than biomass, 100 times less than gas, 35 times less than hydro, 11 times less than solar and 3.75 times less than wind.
Another study, published in 2021 in the journal Environmental Research and conducted by the universities of Harvard, Birmingham, Leicester and University College London, shows that the extraction of fossil fuels in 2018 caused the death of 8.5 million people, or one in five deaths on the planet, more than tobacco and malaria combined.
One of the particularities of the study is that it focused on studying more precisely the fine particles below 2.5 micrometers and its mapping in order to know its impact on the population in relation to its living area. The study specifies that the combustion of fossil fuels would cause fewer deaths in Europe and the United States, about 15%, than in Southeast Asia, about 30%, with a particularly large proportion in China and India. For George Thurston, an expert in air pollution and health at the Medical University of New York, it is obvious that the main cause of the human cost of air pollution is the combustion of fossil fuels.
Two researchers from NASA's Goddard Institute for Space Studies, Pushker Kharecha and James Hansen, published in 2013 in Environmental Science and Technology, an analysis of the long-term impact of nuclear power on human health and the environment, particularly on climate. In particular, this study quantifies and associates the decrease in mortality with the decrease in greenhouse gas emissions, and the authors take the opportunity to point out that without nuclear power, coal-fired power plants would have produced even more energy and emitted even more greenhouse gas pollution.
Taking into account the three major nuclear disasters of Three Mile Island in 1979, Chernobyl in 1986 and Fukushima in 2011, the use of nuclear energy maintains a positive balance compared to other energy sources. According to the calculations made, nuclear energy has prevented about 1.84 million deaths between 1971 and 2009, or about 76,000 deaths per year on average.
These data were obtained by taking into account the direct mortality related to the exploitation of fossil fuels and the deaths related to air pollution and combining them with the figures that would be obtained if fossil fuels were used instead of nuclear energy. The two scientists then deducted the estimated 4,900 nuclear-related deaths between 1971 and 2009.
Fukushima Daiichi nuclear power plantSource: picture alliance / AP Photo
While no direct deaths are associated with Three Mile Island and Fukushima, the death toll associated with Chernobyl remains questionable, with three different reports assessing three different perimeters. In 2005, the official WHO report takes into account radiation exposure and estimates the number of deaths at 4,000. In 2008, the report of the United Nations Scientific Committee on the Effects of Atomic Radiation limited its assessment to the number of deaths associated with the consequences of radioactive emissions and estimated the number of deaths at 43. In 2011, the Union of Conerned Scientists' expert group takes into account the number of deaths to be attributed to fatal cancers induced by the disaster and estimates the number of deaths at 25,000 and then re-evaluates it at 50,000.
On the climate scale, the use of nuclear energy has saved 64 gigatons of CO2 equivalent between 1971 and 2009, which is almost two years of greenhouse gas emissions for the planet. For the period 2010-2050, the study extrapolates the future use of nuclear energy from data from the International Atomic Energy Agency.
The calculations take into account the impact of the Fukushima accident on the development of nuclear energy and anticipate the replacement of nuclear power plants by coal and natural gas plants. The scenarios show an additional death toll of between 420,000 and 7 million people and additional emissions of 84 to 240 gigatons of CO2 equivalents, with the high end of the range representing the worst case scenario, where only coal-fired power plants are used as replacements. Such a scenario would promote the emission of CO2 that would be even closer to the 450 parts per million threshold of CO2 concentrations in the atmosphere that must not be exceeded to avoid a global climate change.