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Difference between revisions of "Nuclear energy"

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**Accidents and emissions cannot be completely eliminated such as [[Three Mile Island]] and the 2011 Japanese disaster. It is recommended that those that live in the area of a nuclear reactor keep supplies of [[Potassium Iodide]]. <ref>[http://www.fda.gov/Drugs/EmergencyPreparedness/BioterrorismandDrugPreparedness/ucm072265.htm FDA Frequently Asked Questions on Potassium Iodide (KI)]</ref>
 
**Accidents and emissions cannot be completely eliminated such as [[Three Mile Island]] and the 2011 Japanese disaster. It is recommended that those that live in the area of a nuclear reactor keep supplies of [[Potassium Iodide]]. <ref>[http://www.fda.gov/Drugs/EmergencyPreparedness/BioterrorismandDrugPreparedness/ucm072265.htm FDA Frequently Asked Questions on Potassium Iodide (KI)]</ref>
 
**Mining inevitably releases radioactive materials into the environment.
 
**Mining inevitably releases radioactive materials into the environment.
**[[Decommissioning]]
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**[[Nuclear decommissioning]]
  
 
=== Waste products ===
 
=== Waste products ===

Revision as of 11:41, 21 March 2011

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Nuclear energy or nuclear power is produced by nuclear power plants using heat generated from nuclear fission in a contained environment to convert water to steam. This powers generators to produce electricity.

Nuclear power is proposed by some people as a partial solution to global warming. These claims are disputed by others due to:

Nuclear power plants operate in most states of the US, in Japan, and across Europe. They produce about 20 percent of the USA's power. Nearly 3 million Americans live within 10 miles (16 km) of an operating nuclear power plant.

How it works

Nuclear power is a type of nuclear technology involving the controlled use of nuclear fission to release energy for work including propulsion, heat, and the generation of electricity.

Nuclear power production makes use of nuclear fissionW reactions that release the binding energyW of uraniumW atoms. In order to be used in the nuclear fuel cycle the uranium 235 in natural uranium must be concentrated. The primary type of nuclear power system used is a boiling water reactor.W

"Too cheap to meter"

"Our children will enjoy in their homes electrical energy too cheap to meter," he declared. ... "It is not too much to expect that our children will know of great periodic regional famines in the world only as matters of history, will travel effortlessly over the seas and under them and through the air with a minimum of danger and at great speeds, and will experience a lifespan far longer than ours, as disease yields and man comes to understand what causes him to age." Lewis L. Strauss Speech to the National Association of Science Writers, New York City, September 16th, 1954 [New York Times, September 17, 1954] [1].

This was the view of Lewis L. Strauss, chairman of the Atomic Energy Commission. This vision didn't happen for reasons such as each plant having to be tailored to fit the need of the surrounding area. New regulations (e.g. for reasons of safety) put constrains on construction. This hiked up costs of building. 


Government subsidies

The UK government in 2010 declared that it would allow additional nuclear plants to be built, but would not support them through subsidies - this included a refusal to act as insurer of last resort. This may effectively kill nuclear power as an option in Britain, especially considering the likelihood of increased insurance costs after the disaster in Japan in March 2011.

History of nuclear disasters

Many releases of nuclear material have occurred around the world. Advocates of nuclear power have argued that modern designs with proper safety considerations are failsafe or at least extremely safe, without the fundamental flaws in design and operation of earlier plants, particularly the Chernobyl plant. This claim appears much weaker in the light of the 2011 Japanese incidents.

2011 Japanese incidents

Several factors contributed to the Fukushima I nuclear accidentsW

  • Poor location close to the sea and very close to sea level. This made certain Japanese plants unprepared for a catastrophic earthquake plus tsunami (in an area where such catastrophes are known to be possible).
  • Lack of preparedness of pumps - some pumps had been inoperable for years[verification needed]
  • An unexpectedly large earthquake and tsunami - or to be more accurate, an inadequate safety margin.

Three Mile Island

On Three Mile Island in 1979 there was a partial core meltdown. Estimates are that the average dose to about 2 million people in the area was only about 1 millirem. To put this into context, exposure from a chest x ray is about 6 millirem. Compared to the natural radioactive background dose of about 100 125 millirem per year for the area, the collective dose to the community from the accident was very small. The maximum dose to a person at the site boundary would have been less than 100 millirem [2]. The Kemeny Commission Report concluded that "there will either be no case of cancer or the number of cases will be so small that it will never be possible to detect them. [3].The public on the other hand would blow this incident way out of proportion. This is largely because a popular movie came out weeks before called The China syndrome that put a negative connotation on nuclear energy and how its run.[verification needed]

1986 Chernobyl

The Chernobyl Disaster was a nuclear reactor accident at the Chernobyl Nuclear Power Plant in Ukraine.It is considered to be the worst nuclear power plant disaster in history. Four hundred times more fallout was released than has been by the atomic bombing of Hiroshima. It caused 56 direct deaths (47 accident workers, and nine children with thyroid cancer), and estimated that there may be 4,000 extra cancer deaths among the approximately 600,000 most highly exposed people. This huge disaster could have been easily avoided had the cooling rods in the reactor didn’t act as a catalyst in the nuclear reaction.[verification needed] Another cause of the failure was the water channels that run through the core needed a more even distribution of water[4].

Types of Radiation

  1. Alpha radiation
  2. Beta radiation
  3. Gamma radiation

The advantages are

  • Lower emissions of many pollutants:
    • Less greenhouse gas emissions than fossil fuels -- although a recent study found that to both replace fossil-fuel-energy use (to mitigate greenhouse gas emissions) and meet the future energy demands, nuclear energy production would have to increase at such a large growth rate that a "cannibalistic" effect becomes important (i.e. nuclear energy must be used to supply the energy for future nuclear power plants.) [5]
    • Possibly less uranium emissions than coal,[verification needed] which contains traces of radioactive material, released into the atmosphere when burnt.
  • Long term fuel source with appropriate technology

The disadvantages are

  • Security issues:
    • Nuclear material cannot be, and has not been, kept safe from those who want it for violent and illegal purposes.[verification needed][neutrality disputed] Having more such material being transported, stored and handled, will inevitably increase that risk.[verification needed]
    • Transport and power generation activities are targets for terrorist attacks.
  • Age issues:
    • Normally it is photovoltaics or wind turbines that gets blamed for having too short expected productive life span. Current nuclear power plants are very old, built in 1970's and 1980's. And they should out of safety reasons (material fatigue) be dismantled ( Decomissioning ) after 35-40 years to be safe enough. Many of european nuclear power plants are going through regular safety updates, that is expensive, to make them stay productive much longer than they were built for.
  • Environmental issues:
    • Accidents and emissions cannot be completely eliminated such as Three Mile Island and the 2011 Japanese disaster. It is recommended that those that live in the area of a nuclear reactor keep supplies of Potassium Iodide. [6]
    • Mining inevitably releases radioactive materials into the environment.
    • Nuclear decommissioning

Waste products

Depleted uranium is a by-product of the concentration process.

Addressing criticisms of nuclear energy

This is an attempt to engage with some of the issues, addressing some of the criticisms made of nuclear energy:

  • The idea that there is only 60 years of Uranium left is geologically debatable. Further, it is possible to expand the supply of uranium through the use of breeder reactors and "fourth generation" nuclear reactors.
  • Radioactive waste can be stored effectively, particularly using means like the Australian Synroc. Further, the radioactivity of the waste does not persist for hundreds of thousands of years - more like thousands - and claims about its radioactivity represent fundamental misunderstandings about the nature of radioactive decay.
  • It's unfair to claim that pro-nuclear people have vested interests. Some do. Some don't. Some anti-nuclear people are running solar cell firms, or have jobs which depend on their viewpoint. But logically you can be both right and have a vested interest. Accusations of vested interest should be made with care, lest they reflect back on you.
  • Construction - putting things in place, wiring them up and testing, is not a particularly CO2 intensive process. The mere fact that a nuclear power plant takes some time to construct does not mean its CO2 load is particularly high. Calculations do point to the CO2 effectiveness of power plants, and wind farms use more metal to fabricate than a nuclear plant able to generate the same power would need.[verification needed]
  • We do other things which generate CO2 than just produce energy, and nuclear plants do take some time to come on line. Certainly, we should do other things to reduce global CO2. But that does not stop nuclear power from having a part to play.
  • Hot rocks and burning garbage are important potential energy sources. Just as we might point to nuclear power distracting us from other options, we can point to wind and solar distracting us from these other important renewable energy sources.please expand
  • We do need to consider the steps needed to make a technology viable, be it fourth generation nuclear reactors, clean coal, wind, solar and other renewables, even fusion power.
  • The Australian political scene, with Howard promoting Nuclear Power, is more complex than would first appear. Howard did, for example, implement changes to the Building Code of Australia which controlled energy usage.please expand
  • Nuclear reactors may be difficult to insure, but this could be because they are not standardised. Further, it is interesting that many anti-nuclear activists challenge market operation in other areas, but assume the insurance market is perfect at assessing risk.
  • If we (in Australia) were to export uranium and store the resultant nuclear waste, we could prevent weapon proliferation.[verification needed] Further, ethically it is strange to be happy to sell something with significant consequences in its use but take no responsibility for them.

This section includes ideas based on Thoughts on Nuclear Power by JohnAugust.

Types of nuclear reactor

Thorium

"I reckon we do need one small reactor on each continent to provide isotopes for diagnostics, but there are three main problems with conventional nuclear power: there’s the risk of meltdown; the problem of radioactive waste … and reactors produce [nuclear] weapons fuel. "I’m in favour of some types of nuclear power which don’t have these problems. Unfortunately political leaders aren’t interested in [these alternative designs, i.e. thorium] because they want the nuclear weapons." - Karl Kruszelnicki[7]

Integral fast reactor

The Integral fast reactor is a type of fast reactor with breeding capabilities.

Suggested projects

  • How does nuclear energy compare with renewable energy sources for total financial cost to the community (i.e. if no subsidies or equal subsidies were given to all forms of energy production)?[Suggested project]
  • How does nuclear energy compare with renewable energy sources for total greenhouse gas emission? All energy should be assessed, including energy used in accessing the raw materials (e.g. uranium for nuclear power and silica for solar cells) and making the energy producing devices (nuclear power plants, solar cell arrays, wind turbines).[Suggested project]
  • How does modern nuclear power compare with coal for the release of radioactive material into the environment? Consider all aspects, including mining and power generation.[Suggested project]

Notes

  1. Too Cheap to Meter?
  2. Backgrounder on the Three Mile Island Accident
  3. wikipedia: Three Mile Island accident
  4. wikipedia:Chernobyl disaster
  5. Pearce, J. M. “Thermodynamic Limitations to Nuclear Energy Deployment as a Greenhouse Gas Mitigation Technology”, International Journal of Nuclear Governance, Economy and Ecology 2(1), pp. 113-130, 2008. http://www.inderscience.com/search/index.php?action=record&rec_id=17358&prevQuery=&ps=10&m=or
  6. FDA Frequently Asked Questions on Potassium Iodide (KI)
  7. Dr Karl Kruszelnicki,W Australian Climate Change Coalition candidate, Dr Karl: 'Keep trying on all fronts', interview with Green Left Weekly, 19 November 2007.

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