Then there is this from the Nuclear Industry:
The main use of nuclear energy is to generate electricity. This is simply a clean and efficient way of boiling water to make steam which drives turbine generators. Except for the reactor itself, a nuclear power station works like most coal or gas-fired power stations. Nuclear energy is best applied to medium and large-scale electricity generation on a continuous basis (ie meeting "base-load" demand). The fuel for it is basically uranium.
…Nuclear energy has distinct environmental advantages over fossil fuels, in that virtually all its wastes are contained and managed - nuclear power stations do not cause any pollution.
Nuclear energy supplies over 16% of the world's electricity, more than the world used from all sources in 1960. Today 31 countries use nuclear energy to generate up to three quarters of their electricity, and a substantial number of these depend on it for one quarter to one half of their supply. Some 10,500 reactor years of operational experience have been accumulated since the 1950s by the world's 440 nuclear power reactors (and nuclear reactors powering naval vessels have clocked up a similar amount).
From the outset, safety of nuclear reactors has been a very high priority in their design and engineering. About one third of the cost of a typical reactor is due to safety systems and structures. The Chernobyl accident in 1986 was a reminder of the importance of this, whereas the Three Mile Island accident in 1979 showed that conventional safety systems work.
At Chernobyl in Ukraine 30 people were killed (mostly by high levels of radiation) and many more injured or adversely affected. This reactor lacked the basic engineering provisions necessary for licensing in most parts of the world (other reactors of that kind still operating have been significantly modified). At Three Mile Island in the USA with a similarly serious malfunction, the effects were contained and no-one suffered any harm or injury.
Nuclear power reactors are expensive to build but relatively cheap to operate. Their economic competitiveness thus depends on keeping construction to schedule so that capital costs do not blow out, and then operating them at reasonably high capacity over many years. By way of contrast, gas-fired power plants are very cheap and quick to build, but relatively very expensive to operate due to the cost of their fuel. With rising gas prices, and the high cost of moving coal long distances, nuclear plants are generally competitive with both gas and coal in most parts of the world, and becoming more so.
Nuclear power produces wastes which are contained and managed, with the cost of this being met by the electricity customer at the time. It does not produce any significant wastes which are dispersed to the environment. It therefore avoids contributing to increased carbon dioxide levels in the atmosphere.
The main wastes produced by "burning" uranium in a nuclear reactor are very hot and radioactive, placing them among the most unpleasant wastes from modern industry. However, these "high-level" nuclear wastes are modest in quantity. Handling and storing them safely is quite straight forward, they simply need to be shielded from human exposure, and cooled. Shielding can be by water, concrete, steel or other dense material, cooling is by air or water.
Transport of nuclear materials:
Safety is the prime requirement with nuclear transports, particularly those of highly-radioactive spent fuel, and the record is impressive. Shielding, and the security of that shielding in any accident, is the key with any nuclear materials, especially those which are significantly radioactive. There has never been any radiation release from an accident involving such materials.
Ionising radiation, such as occurs from uranium ores and nuclear wastes, is part of our human environment, and always has been so. At high levels it is hazardous, but at low levels it is harmless. Considerable effort is devoted to ensuring that those working with nuclear power are not exposed to harmful levels of radiation from it, and standards for the general public are set about 20 times lower still, well below the levels normally experienced by any of us from natural sources.
Avoiding weapons proliferation:
The initial development of atomic energy during and immediately after the second world war was to produce bombs. An early concern when the atom was harnessed for controlled civil use was that this nuclear power should not enable more countries to acquire nuclear weapons. Through the United Nations, procedures were set up to ensure this, and in fact they have been perhaps the most conspicuous success of that body. No nuclear materials such as uranium from the civil nuclear fuel cycle have ever been diverted to make weapons. In fact today the whole picture is reversed in that a lot of military uranium is being brought into the civil nuclear fuel cycle to make electricity, which is widely seen as a positive development, unimaginable 40 years ago. One tenth of US electricity is made from Russian military warheads.
Although this web site focuses on the use of nuclear energy to produce electricity, it is important to note that nuclear energy is also used to produce the radioisotopes used in many parts of our modern world, with health services, industry and even domestic safety very dependent on them. Many homes have smoke detectors which depend on a tiny amount of americium, derived from plutonium made in a nuclear reactor. In the developed countries, about one half of all people will depend on nuclear medicine at some stage of their lives.
This production of medical radioisotopes is all that Australia's reactor at Lucas Heights in Sydney is used for, yet it has been subject to anti-nuclear and environmental protests in the past. It would also appear that should the world need to lower it CO2 Emissions then nuclear or a combination with nuclear at it’s centre for production of base load is the only real alternative to Coal or Gas fired power stations. Some further reading on the Myths and Realities on Nuclear Waste are available here.
Wednesday, September 23, 2009
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