A Comparative Analysis of Accident Risks in Fossil, Hydro, and Nuclear Energy Chains

ABSTRACT

This study presents a comparative assessment of severe accident risks in the energy sector, based on the historical experience of fossil (coal, oil, natural gas, and LPG [Liquefied Petroleum Gas]) and hydro chains contained in the comprehensive Energy-related Severe Accident Database (ENSAD), as well as Probabilistic Safety Assessment (PSA) for the nuclear chain. Full energy chains were considered because accidents can take place at every stage of the chain. Comparative analyses for the years 1969–2000 included a total of 1870 severe (≥ 5 fatalities) accidents, amounting to 81,258 fatalities. Although 79.1% of all accidents and 88.9% of associated fatalities occurred in less developed, non-OECD countries, industrialized OECD countries dominated insured losses (78.0%), reflecting their substantially higher insurance density and stricter safety regulations. Aggregated indicators and frequency-consequence (F-N) curves showed that energy-related accident risks in non-OECD countries are distinctly higher than in OECD countries. Hydropower in non-OECD countries and upstream stages within fossil energy chains are most accident-prone. Expected fatality rates are lowest for Western hydropower and nuclear power plants; however, the maximum credible consequences can be very large. Total economic damages due to severe accidents are substantial, but small when compared with natural disasters. Similarly, external costs associated with severe accidents are generally much smaller than monetized damages caused by air pollution.

Key Words:

• ENSAD database
• severe accident
• energy sector
• comparative risk assessment
• external costs

Acknowledgments

The authors thank Dr. Warren Schenler and three anonymous reviewers for their valuable comments and critiques on an earlier version of this article. This study was partially performed within the Integrated Project NEEDS (New Energy Externalities Development for Sustainability, Contract No. 502687) of the 6th Framework Programme of European Community.

Notes

¹The “Seveso II” Directive (96/82/EC), developed by the European Commission (EC), provides guidelines on a “Major Accident Prevention Policy and Safety Management System,” that is, aiming at the prevention of major accidents involving dangerous substances, and the limitation of their consequences.

²Different currencies were all converted to USD values. To take account of inflation, specific amounts were extrapolated using the U.S. Consumer Price Index (CPI) to obtain year 2000 values.

³The Organisation for Economic Co-operation and Development (OECD) was established in 1961 and currently consists of 30 member countries: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Korea, Luxembourg, Mexico, The Netherlands, New Zealand, Norway, Poland, Portugal, Slovak Republic, Spain, Sweden, Switzerland, Turkey, United Kingdom, United States.

⁴The European Union currently comprises 27 member states. Results in this article are given for EU 25, which includes the former EU 15 countries: Belgium, Germany, France, Italy, Luxembourg, The Netherlands, Denmark, United Kingdom, Ireland, Greece, Portugal, Spain, Austria, Finland, Sweden as well as Czech Republic, Estonia, Cyprus, Latvia, Lithuania, Hungary, Malta, Poland, Slovenia, Slovak Republic that joined recently. Bulgaria and Romania that became member states as of 2007 are not yet considered here.

⁵A failure of a hydropower dam could cause a large number of fatalities in densely populated industrial areas downstream where power is delivered, or a failure may lead to large damages to the costly installations for electricity production (e.g., generators, turbines, transformers).

⁶Note that a recalculation of aggregated indicators for hydropower (i.e., fatalities distributed evenly in the case of multi-purpose dams) would result in about 0.002 and 5.015 fatalities per GW _e yr for OECD and non-OECD countries, respectively, but not change the energy chain ranking (compare Figure 4).

⁷The chain-specific maximum damage or maximum consequences denote the accident with most severe consequences (e.g., fatalities) of a specific energy chain, based on the historical data contained in ENSAD or derived from a Probabilistic Safety Assessment (PSA) for the nuclear chain.

⁸For further reading we suggest references cited in the reports by Burgherr et al. (2004) and Markandya et al. (2004) that were produced within the NewExt project (see introduction). Additionally, a number of other references may be of particular interest (European Commission 1995, 1999, 2003; Jones-Lee and Loomes 1995; Viscusi and Aldy 2003, 2007).

⁹The December 2004 Indian Ocean seaquake (magnitude of 9.1 to 9.3 on the Richter scale) triggered a series of devastating tsunamis. Initial estimates put the death toll in the range of 300,000, but recent analyses reduced it to about 220,000 (e.g., Swiss Re 2006). Nevertheless, this catastrophe is one of the deadliest disasters in modern history.

^a First line: Coal non-OECD without China; second and third line: Coal China 1969–2000, and in parentheses 1994–1999. Note that only data for 1994–1999 are representative because of substantial underreporting in earlier years (Hirschberg et al. 2003a, 2003b).

^b Banqiao/Shimantan dam failures together caused 26,000 fatalities.

^c Only immediate fatalities. In the case of Chernobyl estimates for latent fatalities range from about 9000 for Ukraine, Russia, and Belarus to about 33,000 for the whole northern hemisphere in the next 70 years (Hirschberg et al. 1998). According to a recent study (Chernobyl Forum 2005) by numerous United Nations organizations (IAEA, WHO, UNDP, FAO, UNEP, UN-OCHA, and UNSCEAR) up to 4000 persons could die due to radiation exposure in the most contaminated areas. This estimate is substantially lower than the upper limit of the PSI interval, which, however, was not restricted to the most contaminated areas.

¹⁰In the case of the nuclear chain fatalities could continue to occur over an extended period, therefore total fatalities are split in the following categories: early (immediate) fatalities would occur shortly after exposure, whereas latent fatalities include all those occurring within 70 years from the radioactive release. For details see Burgherr et al. (2004) and Hirschberg et al. (2003a).

¹¹EC: European Commission, IAEA: International Atomic Energy Agency, WHO: World Health Organization, UNSCEAR: United Nations Scientific Committee on the Effects of Atomic Radiation.

¹²UNDP: United Nations Development Programme, FAO: Food and Agriculture Organization of the United Nations, UNEP: United Nations Environment Programme, UN-OCHA: United Nations Office for the Coordination of Humanitarian Affairs; for others see footnote 11.

¹³Emergency workers and persons who were involved in the clean-up operations after the accident.

^a In non-OECD countries, the ranking for immediate fatalities is given for total non-OECD and non-OECD without China because of the dominant influence of the Chinese coal chain; as indicated by the separating slash.

^b The ranking changes if the Chinese dam failures of Banqiao/Shimantan with a total of 26,000 fatalities are excluded from the analysis; as indicated by squared brackets.

^c 150,000 evacuees were reported for both energy chains.

^d Chernobyl accident.