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Letter to The Irish Times |
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Written by David Sowby and Frank Turvey
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Tuesday, 29 March 2011 |
OPINION: Fukushima frightens us all but mankind has never walked away from a technology, no matter how hard it is to master, write DAVID SOWBY and FRANK TURVEY
EVER SINCE a human being first lit a fire, humankind has striven to harness the forces of nature in ways that yielded benefits but which also carried risks.
As civilisation progressed, the benefits of any particular advance became more substantial but, by and large, so also did the risks.
But from the boiler explosions of the 19th century, through hydroelectric dam collapses, mining and oil-rig disasters, train and air crashes, Bhopal and Chernobyl, the response of humanity has never been to abandon a technology, but to derive lessons from what has happened so as to make the benefits available more safely in the future.
Thus will it be also with nuclear power in the aftermath of the Fukushima accident.
What has happened at Fukushima is a disaster for Japan, but it need not be one for the nuclear industry at large, provided some obvious lessons are learned. These must be learned and applied by the nuclear industry, but this will be possible only after the facts are clearly known.
However, even at this stage, it is important to put the event into context. There are more than 400 nuclear power reactors operating efficiently and safely worldwide. Two particular sets of boiling water reactors (BWRs) (six at Daiichi and four at Daini) are at the Fukushima site and were suddenly dealt a ferocious blow by a most severe earthquake and tsunami.
At least four reactors at the Daiichi plant dating from the 1970s have been severely damaged. As yet, there is no evidence of any damage at the more modern BWRs at Daini, which shut down automatically after the earthquake and remained safe, showing the considerable development in reactor technology that has occurred in as short an interval as 10 years. Indeed, since the 1980s further huge improvements have been made, with the result that today’s and tomorrow’s reactors are and will be many times safer than their predecessors.
The tsunami by itself has caused some 10,000 deaths and a similar number of missing people, enormous disruption and extensive damage. In comparison – and assuming no further adverse development – the nuclear crisis, although very serious, has had relatively minor consequences on the population.
It has certainly caused a great deal of anxiety and disruption of large numbers by evacuation and, of course, significant economic loss, but no injury or loss of life among the public.
Crucially, the lessons to be learned globally must relate to the siting of nuclear power plants in earthquake zones, specifically to siting near those coasts that could be susceptible to tsunamis. Future planning of such plants must be designed to survive a tsunami of the size that occurred. It appears that the Daini plants were so designed.
In the context of the use of nuclear power worldwide, it can be anticipated that Fukushima will take its place in the history of nuclear power as a major point on a challenging learning curve, especially in respect of plant-siting, but undoubtedly also in respect of issues relating to plant cooling systems, as well as many other aspects of the handling of a major emergency.
As far as cooling is concerned, it should be noted that a crucial feature of the latest generation of nuclear reactors is the use of passive cooling, ie, the capability of a reactor to cool itself by natural circulation alone, without the dependence on electricity supply for pumping, which was so central to all the problems at Fukushima.
Comparisons are being made between the Fukushima accident and that at Chernobyl. Such comparisons are unreasonable and without foundation. The Chernobyl reactor was operating at power when some operators broke basic safety rules and conducted an unauthorised, dangerous experiment.
Within minutes this caused a runaway power surge to an extent that the power produced was equal to the total power generated by all the reactors in the world at that time. In addition, the moderator was graphite, which, being carbon, burned easily, producing particulate matter that spread widely.
At Fukushima, the moderator is water and, as the reactor was shut down, with all control rods fully inserted, a power surge could not occur.
What are the implications of Fukushima for Ireland? It will require a more measured appraisal of the full consequences of the accident before its significance for the possible future use of nuclear power in Ireland can be definitively assessed.
All the same, even at this point we cannot emphasise too strongly the importance of a reliable supply of safe, affordable and clean energy for a modern society, which is as important to our wellbeing as clean air and water. In coming years, after our economic recovery, we shall need more energy than we are currently consuming. From where is this energy to come?
The mental block regarding nuclear power that exists in the consciousness of a section of the Irish public will not be removed by the events at Fukushima. Neither though will Fukushima alter the escalating cost and scarcity of oil and gas, the limitations of what wind and other so-called renewable sources of energy can offer or the difficulty of meeting climate-change targets, nor will it reduce our purchases of nuclear-generated electricity from Britain.
Our new Government must examine, at an early date, the potential and practicality of nuclear energy for this country. In doing so, it should seek the assistance of international energy experts such as those at the UN, OECD and EU, about the safest and most reliable modern power reactors that would be suitable for our needs.
David Sowby is a physician who specialised in radiation protection and was scientific secretary of the International Commission on Radiological Protection (ICRP). Frank Turvey is a fellow of the Institute of Nuclear Engineers and a former member of the Radiological Protection Institute of Ireland.
They are members of Better Environment with Nuclear Energy, a group that supports the use of nuclear power and seeks to promote what it regards as balanced debate on the issue. Dr Tom O’Flaherty assisted in the preparation of this article. |
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