Which energy source does not harm the environment

​​Pierre Friedlingstein, Matthew W. Jones, Michael O’Sullivan, Robbie M. Andrew, Dorothee, C. E. Bakker, Judith Hauck, Corinne Le Quéré, Glen P. Peters, Wouter Peters, Julia Pongratz, Stephen Sitch, Josep G. Canadell, Philippe Ciais, Rob B. Jackson, Simone R. Alin, Peter Anthoni, Nicholas R. Bates, Meike Becker, Nicolas Bellouin, Laurent Bopp, Thi Tuyet Trang Chau, Frédéric Chevallier, Louise P. Chini, Margot Cronin, Kim I. Currie, Bertrand Decharme, Laique M. Djeutchouang, Xinyu Dou, Wiley Evans, Richard A. Feely, Liang Feng, Thomas Gasser, Dennis Gilfillan, Thanos Gkritzalis, Giacomo Grassi, Luke Gregor, Nicolas Gruber, Özgür Gürses, Ian Harris, Richard A. Houghton, George C. Hurtt, Yosuke Iida, Tatiana Ilyina, Ingrid T. Luijkx, Atul Jain, Steve D. Jones, Etsushi Kato, Daniel Kennedy, Kees Klein Goldewijk, Jürgen Knauer, Jan Ivar Korsbakken, Arne Körtzinger, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Sebastian Lienert, Junjie Liu, Gregg Marland, Patrick C. McGuire, Joe R. Melton, David R. Munro, Julia E.M.S Nabel Shin-Ichiro Nakaoka, Yosuke Niwa, Tsuneo Ono, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Thais M Rosan, Jörg Schwinger, Clemens Schwingshackl, Roland Séférian, Adrienne J. Sutton, Colm Sweeney, Toste Tanhua, Pieter P Tans, Hanqin Tian, Bronte Tilbrook, Francesco Tubiello, Guido van der Werf, Nicolas Vuichard, Chisato Wada Rik Wanninkhof, Andrew J. Watson, David Willis, Andrew J. Wiltshire, Wenping Yuan, Chao Yue, Xu Yue, Sönke Zaehle, Jiye Zeng. Global Carbon Budget 2021, Earth Syst. Sci. Data, 2021.

Per capita electricity consumption in the EU-27 in 2021 was around 6,400 kWh.

1 terawatt-hour is equal to 1,000,000,000 kilowatt-hours. So, we get this figure by dividing 1,000,000,000 by 6,400 ≈ 150,000 people.

The following sources were used to calculate these death rates.

Fossil fuels and biomass: these figures are taken directly from Markandya, A., & Wilkinson, P. (2007). Electricity generation and health. The Lancet, 370(9591), 979-990.

Nuclear: I have calculated these figures based on the assumption of 433 deaths from Chernobyl and 2314 from Fukushima. These figures are based on the most recent estimates from UNSCEAR and the Government of Japan. In a related article, I detail where these figures come from.

I have calculated death rates by dividing this figure by cumulative global electricity production from nuclear from 1965 to 2021, which is 96,876 TWh.

Hydropower: The paper by Sovacool et al. (2016) provides a death rate for hydropower from 1990 to 2013. However, this period excludes some very large hydropower accidents which occurred prior to 1990. I have therefore calculated a death rate for hydropower from 1965 to 2021 based on the list of hydropower accidents provided in Sovacool et al. (2016), which extends back to the 1950s. Since this database ends in 2013, I have also included the Saddle Dam accident in Laos in 2018, which killed 71 people.

The total number of deaths from hydropower accidents from 1965 to 2021 was approximately 176,000. 171,000 of these deaths were from the Banqian Dam Failure in China in 1975.

I have calculated death rates by dividing this figure by cumulative global electricity production from hydropower from 1965 to 2021, which is 138,175 TWh.

Solar and wind: these figures are taken directly from: Sovacool, B. K., Andersen, R., Sorensen, S., Sorensen, K., Tienda, V., Vainorius, A., … & Bjørn-Thygesen, F. (2016). Balancing safety with sustainability: assessing the risk of accidents for modern low-carbon energy systems. Journal of Cleaner Production, 112, 3952-3965. In this analysis the authors compiled a database of as many energy-related accidents as possible based on an extensive search of academic databases and news reports, and derived death rates for each source over the period from 1990 to 2013. Since this database has not been extended since then, it’s not possible to provide post-2013 death rates.

UNSCEAR (2008). Sources and effects of Ionizing Radiation. UNSCEAR 2008 Report to the General Assembly with Scientific Annexes. Available online.

Report of the United Nations Scientific Committee on the Effects of Atomic Radiation. General Assembly Official Records, Sixty-eighth session, Supplement No. 46. New York: United Nations, Sixtieth session, May 27–31, 2013.

Schlömer S., T. Bruckner, L. Fulton, E. Hertwich, A. McKinnon, D. Perczyk, J. Roy, R. Schaeffer, R. Sims, P. Smith, and R. Wiser, 2014: Annex III: Technology-specific cost and performance parameters. In: Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Edenhofer, O., R. Pichs-Madruga, Y. Sokona, E. Farahani, S. Kadner, K. Seyboth, A. Adler, I. Baum, S. Brunner, P. Eickemeier, B. Kriemann, J. Savolainen, S. Schlömer, C. von Stechow, T. Zwickel and J.C. Minx (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

The IPCC AR5 report was published in 2014, and relies on studies conducted several years prior to its publication. For technologies which have been developing rapidly – namely solar, wind and other renewables, production technologies and intensities have changed significantly since then, and will continue to change as energy systems decarbonize. Life-cycle figures for nuclear, solar, wind and hydropower have therefore been adopted by the more recent publication by Pehl et al. (2017), published in Nature Energy.

Pehl, M., Arvesen, A., Humpenöder, F., Popp, A., Hertwich, E. G., & Luderer, G. (2017). Understanding future emissions from low-carbon power systems by integration of life-cycle assessment and integrated energy modelling. Nature Energy, 2(12), 939-945.

The Carbon Brief provides a clear discussion of the significance of these more recent lifecycle analyses in detail here.

Since oil is conventionally not used for electricity production, it is not included in the IPCC’s reported figures per kilowatt-hour. Figures for oil have therefore been taken from Turconi et al. (2013). It reports emissions in kilograms of CO2eq per megawatt-hour. Emissions factors for all other technologies are consistent with results from the IPCC. The range it gives for oil is 530–900: I have here taken the midpoint estimate (715 kgCO2eq/MWh, which is also 715 gCO2eq/kWh).

Turconi, R., Boldrin, A., & Astrup, T. (2013). Life cycle assessment (LCA) of electricity generation technologies: Overview, comparability and limitations. Renewable and Sustainable Energy Reviews, 28, 555-565.

Burgherr, P., & Hirschberg, S. (2014). Comparative risk assessment of severe accidents in the energy sector. Energy Policy, 74, S45-S56.

McCombie, C., & Jefferson, M. (2016). Renewable and nuclear electricity: Comparison of environmental impacts. Energy Policy, 96, 758-769.

Hirschberg, S., Bauer, C., Burgherr, P., Cazzoli, E., Heck, T., Spada, M., & Treyer, K. (2016). Health effects of technologies for power generation: Contributions from normal operation, severe accidents and terrorist threat. Reliability Engineering & System Safety, 145, 373-387.

Luderer, G., Pehl, M., Arvesen, A., Gibon, T., Bodirsky, B. L., de Boer, H. S., … & Mima, S. (2019). Environmental co-benefits and adverse side-effects of alternative power sector decarbonization strategies. Nature Communications, 10(1), 1-13.

Hertwich, E. G., Gibon, T., Bouman, E. A., Arvesen, A., Suh, S., Heath, G. A., … & Shi, L. (2015). Integrated life-cycle assessment of electricity-supply scenarios confirms global environmental benefit of low-carbon technologies. Proceedings of the National Academy of Sciences, 112(20), 6277-6282.

Pollutant controls in advanced economies such as the US and Europe are advanced, and have been in place for many decades. Controls tend to be lower in middle-to-low-income countries.

Wang, S., Yu, C., & Hao, J. (2011). Control of NOx emissions from power plants: Experiences of United States and its implications for China. Chinese Journal of Environmental Engineering, 5(6), 1213-1220.

However many have made significant progress in recent years. This paper details the progress made in China.

Wang, G., Deng, J., Zhang, Y., Zhang, Q., Duan, L., Hao, J., & Jiang, J. (2020). Air pollutant emissions from coal-fired power plants in China over the past two decades. Science of the Total Environment, 741, 140326.

Xie, L., Huang, Y., & Qin, P. (2018). Spatial distribution of coal-fired power plants in China. Environment and Development Economics, 23(4), 495-515.

Coal: 24.62 deaths per TWh * 10,042 TWh = 247,000 deaths

Oil: 18.43 deaths per TWh * 852 TWh = 16,000 deaths

Gas: 2.82 deaths per TWh * 6,098 TWh = 17,000 deaths.

This sums to a total of 280,000 people.

Lelieveld, J., Klingmüller, K., Pozzer, A., Burnett, R. T., Haines, A., & Ramanathan, V. (2019). Effects of fossil fuel and total anthropogenic emission removal on public health and climate. Proceedings of the National Academy of Sciences, 116(15), 7192-7197.

Vohra, K., Vodonos, A., Schwartz, J., Marais, E. A., Sulprizio, M. P., & Mickley, L. J. (2021). Global mortality from outdoor fine particle pollution generated by fossil fuel combustion: Results from GEOS-Chem. Environmental Research, 195, 110754.

Chowdhury, S., Pozzer, A., Haines, A., Klingmueller, K., Münzel, T., Paasonen, P., … & Lelieveld, J. (2022). Global health burden of ambient PM2.5 and the contribution of anthropogenic black carbon and organic aerosols. Environment International, 159, 107020.

Leliveld et al. (2019) estimate that 8.8 million people die from all sources of air pollution each year. If we multiply this figure by 12%, we get 1.1 million people.

Vohra et al. (2021) estimate that the death toll is 2.4 times higher than Leliveld et al. (2019). This would give a figure of 2.55 million deaths [1.1 million * 2.4]

UNECE (2021). Lifecycle Assessment of Electricity Generation Options. United Nations Economic Commission for Europe.