|Volume 5 Issue 06 | June 2011|
The Challenge of Fukushima Nuclear Accident
The benefits of nuclear power are greater than the risks, suggests ABDUL MATIN.
Nuclear energy first came to the limelight as a weapon of mass destruction with the explosion of two devastating bombs at Hiroshima and Nagasaki at the end of World War II on August 6 and 9, 1945. Even though the peaceful use of nuclear energy was started in the mid 1950s with the commercial production of electricity, the trauma generated by the atom bombs of World War II has not eroded from human memory. The news of any nuclear accident is, therefore, viewed with horror and is given wide publicity in the information media.
Not many people are, however, aware that the nuclear power is credited to have the least number of fatalities in comparison with other sources of energy. For example, the direct fatalities in energy chains during 1969-2000 are 30,014 for hydro, 20,259 for coal, 2,043 for natural gas and 56 (revised figure) only for nuclear power1.
Nuclear power passed through many hurdles since the mid 1950s. The first major accident in a civilian nuclear power plant took place at Three Mile Island in the US in 1979. There was neither any fatality nor any major release of radioactivity to the atmosphere in this accident. The second accident, a more serious one, occurred in 1986 in the Chernobyl Nuclear Power Plant in an area of the former Soviet Union, now Ukraine.
The nuclear industry took lessons from all such accidents and improved the safety features of nuclear reactors over the last 50 years. It was believed that another major nuclear accident after Chernobyl was most unlikely. But it happened at Fukushima Dai-ichi Nuclear Power Plant in Japan on March 11, 2011, though the time gap increased from seven years between the first two major accidents to a quarter of a century between the second and the third ones indicating that the probability of such accidents has significantly decreased.
Even though the Fukushima nuclear accident has been upgraded to a level 7 accident on an international scale, there has not been any direct fatality in the accident. All the civilian populations from the exclusion zones have been moved to safer places. Access to high radiation or contaminated areas is strictly restricted. All plant workers are performing their duties wearing protective clothing and strictly following regulatory guidelines for work in high radiation areas.
Like in the past, an anti-nuclear lobby has raised its voice again to close all nuclear power plants on safety considerations, without taking into account the implications of such a proposition. There are now 442 nuclear power plants in operation and 65 nuclear plants under construction worldwide. It is widely believed that closures of all the nuclear power plants will sharply increase the prices of other fuels, mainly oil and coal, making electricity generation prohibitively expensive. High prices of fossil fuels are likely to initiate another economic recession before full recovery from the recent one.
It is worth noting that the Fukushima nuclear reactors are of very old designs and were built in the 1970s. Germany has temporarily shut down seven of its oldest power plants whose operating lives were extended after expiry of their design lives. Japan ordered the closure of three reactors at Hamaoka Nuclear Power Plant on concerns that the plant was unprepared to withstand a major earthquake. The units will remain shut until a new seawall is built and the backup systems are improved. The remaining two reactors at the plant were shut earlier for decommissioning. It has been recently announced that Japan has no plan to close any more nuclear power plants even though its present nuclear energy policy is under review. There are indications that Japan will scale down its plan to have 50% electricity from nuclear energy by 2030, perhaps increasing reliance on renewable sources like solar and wind energy.
Most other countries with operating nuclear power plants like Russia, China and India are continuing with their present policies of expansion of nuclear power. A Chinese nuclear safety expert is reported to have commented in the state media after the Fukushima accident, "We're not going to stop eating for fear of choking"2.
It may be noted that we all take risks in our daily lives. We fly by planes and travel by automobiles being fully aware of the risks involved. Not all of us are aware that the probability of one being killed by radiation from a nuclear accident is significantly less than that of being killed by a plane crash or an automobile accident.
In a study (WASH-1400, 1975), it was shown that “individual persons have less than 1 in 5,000,000,000 chance of dying on a yearly basis from the operation of 100 nuclear power plants in the United States. This is less than yearly risk of being struck by lightning and being killed (1 in 20,000,000), being in a fatal auto collision (1 in 3,000 chance of dying), or any other accident risk mentioned in WASH-1400.”3
In a later study (NUREG-1150, 1991), it was shown that the average probability of an individual early fatality per reactor per year is 1 in 50 million for a pressurised water reactor and 1 in 20 billion for a boiling water reactor.4 Needless to emphasise that such probabilities are insignificant quantities. Moreover, nuclear power is also the cleanest form of energy as it produces practically no carbon dioxide that is believed to cause global warming and climate change.
Modern generation-III nuclear power reactors, like the ones being considered to be built at Rooppur, are designed with passive safety features and are more robust in construction. Such nuclear reactors can have their emergency core cooling systems in operation without any electricity, the flow of water through the core being governed by gravity and natural convection. Both gravity and convection flows are natural processes which cannot fail. It may be mentioned here that the failures of the emergency core cooling systems of the operating nuclear reactors due to absence of electrical power caused the accidents at the Fukushima Nuclear Power Plant.
It is true that the Fukushima nuclear accident has posed a serious challenge to humankind. We must confront this challenge with our knowledge, intellect and ingenuity, the most valuable human qualities that helped us to overcome difficult challenges in the past. Safe utilisation of nuclear energy is not beyond human capability. If we decide to retreat and close all nuclear power plants just because of a few isolated nuclear accidents, we shall practically surrender our most valuable human qualities to this challenge. If we do it once, shall we be able to confront bigger challenges in the future? Will it not be the beginning of the end of human civilisation from the planet, even without nuclear power?
1)World Nuclear Association: Safety of Nuclear Power Reactors, http://www.world-nuclear.org/info/inf06.html
2)Associated Press, http://www.google.com/hostednews/ap/article/ALeqM5iO9z7h-kws9z8JwJm9h04Luv57TQ?docId=c4393ef333854de4b2f909abe1b68c8a
3)The Reactor Safety Study, WASH-1400 http://en.wikipedia.org/wiki/WASH-1400
Abdul Matin is a former Chief Engineer of Bangladesh Atomic Energy Commission.
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