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Energy Strategies in Global Warming: Is Nuclear Energy the Answer?
Posted on Friday, July 08, 2005 @ 22:55:45 GMT by vlad
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From Andrew Michrowski (PACENET): ISIS Press Release 08/07/05
Nuclear energy makes economic nonsense and ecological disaster and provides great opportunities for terrorists. Peter Bunyard
Peter Bunyard will be speaking at Sustainable World Conference, 14-15 July 2005, Details on ISIS website http://www.i-sis.org.uk/SWCFA.php
Human-induced global warming is already upon us. The trends in fossil fuel use and the release of greenhouse gases from all human activities, including agriculture, indicate that worldwide we will be hard pushed to achieve the 60 to 80 per cent reduction in greenhouse gases necessary to stabilise greenhouse gas levels in the atmosphere at 550 parts per million (ppm) before the century is out. That’s the upper limit before climate change events become extreme and devastating, according to climatologists [1].
The carbon dioxide level is currently close to 380 ppm in the atmosphere, more than 30 per cent up on the pre-industrial level of 280 ppm. Even at 400 parts per million, which will be reached within 10 years at the current rate of increase of 2 ppm per year, average global temperatures will rise by 2 deg.C [2].
In its scientific review, Climate Change 2001, the Intergovernmental Panel on Climate Change (IPCC) predicts that business-as-usual (BAU) activities across the planet could lead to an average temperature rise of as much as 5.8 deg. C within the century. But such predictions, disturbing as they are, do not take into account the impact of global warming on terrestrial vegetation, including the world’s tropical rainforests. Peter Cox and his colleagues at the Hadley Centre of UK Met Office have elaborated climate models that incorporate a dynamic carbon cycle. They predict that, within half a century, the BAU scenario will cause soils and vegetation to switch abruptly from a sink for atmospheric carbon to a source. That would mean not only the loss of the current capacity to withhold and remove carbon dioxide from the atmosphere, but in addition, the release of carbon from soils and vegetation that has accumulated over the past 150 years.
The net result could be a doubling of current concentrations of greenhouse gases within a matter of years. Adding in the fossil fuel emissions could take the levels of carbon dioxide to four times pre-industrial levels, i.e 1 000 ppm. The positive feedback from the loss of terrestrial carbon further heats up the earth’s surface, and the average surface terrestrial temperature could rise by as much as 9 deg. C instead of the predicted 5.8 deg. C; temperatures as high have not been experienced for more than 40 million years [3].
The soil/vegetation feedback on global warming is not the only one; we face other powerful positive feedbacks, including the change in albedo (the fraction of solar energy reflected back into space) as ice vanishes from the Arctic Circle and from parts of Antarctica where grass is establishing itself for the first time in millions of years [4]. In addition, the potential release of methane from the oceans overlying the vast sediments of the Amazon Fan, or in the permafrost regions of the Northern Hemisphere, could lead to the large changes in climate that were responsible for the mass extinctions of the Permian more than two hundred million years ago.
It has emerged that the Greenland ice sheet is less stable than previously thought. Its rapid melting would raise sea levels by several metres. Moreover, the Gulf Stream is diminishing in strength because of the influx of fresh water into the Arctic Circle [5].
In short, the climate system as we know it is poised on the edge of a profound transition. Once past a point of no return, terrestrial organisms including human beings will have little or no time to adjust and their future on this planet could well be jeopardized.
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Do you send it to loss-making British Nuclear Fuels (BNF) for reprocessing, with all that entails in terms of discharges of radioactive waste into the Irish Sea and the atmosphere? That being the case, do you continue sanctioning the production of Mixed Oxide Fuel (MOX), which makes economic nonsense, as well as a dubious saving on uranium and is a security nightmare (see below)? Or do you reduce costs by storing the spent fuel intact?
As to the use of MOX, many critics within and outside the industry have repeatedly pointed out that the gains are far outweighed by economic and environmental problems. In France, reprocessing spent fuel to extract plutonium for MOX fuel manufacture will save no more than 5 to 8 per cent on the need for fresh uranium. Meanwhile, as experience in both France and Britain has shown, reprocessing spent reactor fuel leads to a hundredfold or more increase in the volume of radioactive wastes. In the end, all the materials used, including tools, equipment and even the buildings become radioactive and have to be treated as a radioactive hazard.
It is also highly questionable whether the use of MOX fuel will actually reduce the amount of plutonium that has been generated after half a century of operating reactors, both military and civil. Worldwide, more than 1 500 tonnes of plutonium have been generated, of which some 250 tonnes have been extracted for making bombs and another 250 tonnes extracted as a result of reprocessing the spent fuel from ‘civilian’ reactors. Apart from its military-grade plutonium - plutonium relatively pure in the 239 isotope - Britain now has some 50 tonnes of lower quality reactor-grade plutonium contaminated with other, less readily-fissionable isotopes such as 241 [16].
Because of the continued reprocessing of spent reactor fuel in commercial reprocessing plants in Britain, France, Russia and Japan, the world will have some 550 tonnes of separated civil plutonium by the year 2010, enough to produce 110 000 nuclear weapons. ...
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Mixed oxide fuel, containing up to 5 per cent plutonium, is ideal material for terrorists, being no more than mildly radioactive compared with spent reactor fuel, and in a form from which the plutonium can be easily extracted. Just one MOX fuel assembly contains some 25 kilograms of plutonium, enough for two weapons. A reactor, modified to take the plutonium-enriched fuel for up to 30 per cent of the reactor core, has some 48 MOX fuel assemblies...
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On Sunday 12 June, 2005, the BBC reported that a leak of highly radioactive waste containing enough uranium and plutonium to make several atomic weapons had gone unnoticed for more than 8 months [18]. It appears that a pipe in British Nuclear Fuels’ thermal oxide reprocessing plant at Sellafield in Cumbria had fractured as long ago as last August, spewing nitric acid with its deadly load of radionuclides onto the floor. The leak, containing as much as 20 tonnes of uranium and 160kg of plutonium, was discovered only in April of this year.
British Nuclear Fuels has justified the use of the reprocessing plant as being essential for the production of mixed oxide fuel from the spent fuel taken from the UK’s Advanced Gas Reactors. As a result of the leak, the nuclear inspectorate has ordered British Nuclear Fuels to shut down THORP, the thermal oxide reprocessing plant. Just how the spilt waste can be removed remains to be seen, but once again the accident reinforces concerns that the nuclear industry, quite aside from its poor economic showing, can never be made safe enough.
In addition, the Environment Agency inspectors told BNF that it had to improve the way it discharged low level radioactive waste into the Irish Sea, now probably one of the most contaminated waters in the world. Some commentators estimate it will take considerably more than a century to clean up the radioactive waste that the industry has already discharged into the environment, at a cost of well over £50 000 million. ...
Read the whole article here: Is Nuclear Energy the Answer?
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Re: Energy Strategies in Global Warming: Is Nuclear Energy the Answer? (Score: 1)
by vlad on Tuesday, July 12, 2005 @ 22:01:07 GMT
(User Info | Send a Message) http://www.zpenergy.com | Dear colleagues,
Please find below a few thoughts rapidly assembled. Bunyard, the author of the ISIS paper offers a somewhat alarmist perspective on the upcoming global warming. He is probably right. His views on nuclear power are also pessimistic. The problem is that, in fairly complex matters, it is impossible to provide comprehensive and balanced information in a short, simple paper. It also difficult to evaluate Bunyard’s paper because his references are accessible only to ISIS members.
From the content of the e-mail, what seems to be missing is a comprehensive review of the advantages and disadvantages of different means of generating or saving energy. To be convincing, such a review must examine technical, financial, public health aspects of each option, but also all indirect (often hidden) environmental, public and occupational health aspects of the various options. For example, I recently found that apparently promising perspectives of biodiesel fuel do not mention that their production requires more input energy than it generates when infrastructures and all steps of production and distribution are taken into account. The late French agronomist René Dumont was already saying that for corn production in the mid 1950's – although he was talking about the amount of usable calories contained in corn.
Nuclear energy has a bad name in part because of the fear of radiation. That fear is justified, just as that of UV, heat, cold…. What is not taken into account is the notion of threshold. Too much UV is bad, but not enough his also bad. Swallowing 100 aspirins at once kills, one per day may save lives. Paracelsus (early 16th century) said that “dose makes the poison”. This is still true today. Life appeared and has evolved in an environment at least 10 times more radioactive than today. Yet, can we say that evolution went that badly? We are ourselves naturally radioactive (one third of our yearly dose of radiation comes from our own body); we eat and breathe natural radioisotopes (K-40 in fruits, meat, ...; C-14 in the air; radon, ...). About 20,000 nuclear disintegrations emit gamma and beta rays per second in our body. Should we stop eating bananas because they are rich in potassium? The ratio of radioactive to stable K is fixed in nature and cannot be changed.
Who would refuse to travel to, or live in Denver, Colorado (or New Mexico, Idaho, Utah, …) because the annual radiation dose there reaches in places like Denver about half the limit for RADIATION WORKERS? Any nuclear facility or nuclear medicine department that would expose its workers to such levels would be closed by regulatory authorities. In India, Brazil, Iran, there are places where natural radiation levels are 2 or 3 times larger than limits for radiation workers, without detectable negative effects. Air travel, mountain vacation also increase our exposure to radiation. If low dose radiation is that bad, we should evacuate the planet (although radiation in space is worse).
There is the problem of spent nuclear fuel. Getting close to it unprotected is deadly. Storing and reprocessing have their problems. However, we can learn from nature, which ran its own nuclear reactor 2 billions years ago in Oklo, Gabon, when natural uranium contained about 3% U-235, against 0.7% today. 3% is close to the U-235 content in enriched nuclear fuels today. That reactor operated for close 1 million years at a depth between 11 and 300 metres, without shielding of course. Fission products and actinides migrated at most a few centimetres away from the reactor areas, without containment. They were trapped locally in clay and soil. Two billion years latter, they or their decay products are still there, not in the water table or at the surface of the ground.
Nuclear energy has its own real problems and advantages, but it is absolutely necessary to examine all of them with a dispassionate mind, without a priori prejudices, and taking ALL aspects into account. We should make an effort to put things in perspective and to judge using facts, not emotions or impressions. We can also do as much as we can to develop new, elegant methods to get rid of spent fuels and other radioactive wastes. That would go a long way toward modifying the perception of nuclear risks in less than a generation, hopefully! It took about one generation to go from radium toothpaste to fear of everything radioactive.
Please forgive this rather long discussion. I hope it can be useful and I would be please to answer any question my rambling may raise.
Best regards to all,
Philippe Duport |
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