Is nuclear energy the deadliest of them all?

Over the past several hundred years, with the deepening of the exchange-based economy, a stratification of society has emerged: we are alienated from the people whose products we ultimately own and consume. We are equally alienated from the people we impact - both positively and negatively - by our economic behavior. This social and physical distance between economic agents often manifests itself in the indiscriminate consumption of goods that are often produced at the cost of human life. In its current form, energy is one such good.

While visuals of nuclear mushroom clouds haunt public memory, we remain largely uninformed about risks and fatalities that emanate from other sources of fuels that are far more in abundance. Due to the very nature of such events, miners crushed under the earth and people succumbing to respiratory ailments remain invisible in the public eye.

The Paul Scherrer Institut in Switzerland maintains the Energy-Related Severe Accident Database (ENSAD) which focuses on severe accidents (as such accidents not only have a large impact, they also influence public perceptions and energy politics). ENSAD is one of the most comprehensive global databases on such accidents, allowing objective studies on risks associated with each fuel.

This database reveals that between 1970 and 2005, in the energy sector, there were 2,368 severe accidents (defined as events which resulted in 5 or more deaths in its immediate aftermath). These accidents resulted in 90,451 fatalities. The table below provides a breakdown by energy source.

Two things stand out from this data. One, fatalities from hydropower are alarmingly high, given there have been only 13 accidents. This number is high largely because the Binqiao and Shimatan dam failures in 1975 in China alone led to over 26,000 immediate deaths. Two, for all the fear we have of nuclear energy, there has been only one severe accident which claimed 31 lives. Something does not feel right about this number, which we will get to a little later.

To appreciate the relative accident risks posed by energy sources, deaths per unit of energy provide a clearer picture. While studies on these lines show a variance in results owing to differing assumptions, time periods and regions in consideration, they reveal a characteristic that is unmistakable: coal poses the highest accident risk among energy sources, but for that one major hydropower accident in China. The table below summarizes the findings of a few key studies.

Curiously, nuclear energy poses the lowest accident risk according to these studies. In fact, the one accident with 31 deaths mentioned in the previous table was the infamous Chernobyl nuclear disaster of 1986. In fact, the 2011 Fukushima disaster in Japan led to zero deaths following the radiation exposure.

If these numbers seem murky to you, it is because they only take into account immediate deaths due to the accident, not deaths due to the long-term impacts on health. Estimating fatalities due to long term impacts is a far more challenging task due to several complexities involved. As a result of this, there have been a wide range of calculations.

Estimates of premature deaths due to long-term impacts on health caused by Chernobyl range from 9000 by the WHO to over 90,000 by Greenpeace (whose report has been criticized by the United Nations' Chernobyl Forum for not relying on scientifically robust peer-reviewed studies). In the case of Fukushima, a study predicts 130-180 premature deaths in the future attributable to the accident. Understandably, we have learned to resist nuclear power plants in our backyards.

On the other hand, fossil fuels continue to claim tens of thousands of lives every year to a largely muted response. Coal, for instance, is estimated to lead to 13,000 premature deaths in the United States and 18,000 deaths in Europe every year. A study claimed that air pollution (largely from the burning of fossil fuels) leads to somewhere between 10,000 to 30,000 premature deaths every year in Delhi alone. Yet another study estimated that 670,000 people died prematurely in China in 2012 alone due to health ailments triggered by the country's dependence on coal. In India, PM2.5 pollution which is produced by all types of combustion including motor vehicles, power plants, industry and agricultural burning, led to 627,000 deaths. Globally, WHO estimated 7 million deaths due to air pollution in 2012. While this air pollution is caused by a host of factors including dust and forest fires, the combustion of fuels is a significant contributor. (Then there are international and civil wars triggered by energy resource politics – the toll of which would be harder still to estimate).

Clearly, even as nuclear energy receives much of the attention due to the expectation of devastatingly spectacular accidents, the fatalities from other forms of energy go nearly unnoticed as they feel more distant. We remain far too alienated from the coal miners and the artisans who quietly suffer from ailments caused by our collective energy choices. Even as renewable sources of energy evolve and develop, traditional sources of energy will continue to be the mainstay in the energy mix for the next several decades. In fact, India plans to double coal production in the next several years - a move that hasn't invited protests, not least those comparable to the ones centered around nuclear power plants.