Nuclear power and Alismatales: Difference between pages

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{{Taxobox_begin | color = lightgreen | name = Alismatids}}

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{{Taxobox_image | image = [[Image:Lemna trisulca0.jpg|250px|Lemna trisulca]] | caption = Ivy Duckweed (''Lemna trisulca'')}}

:''This article is about power derived from [[nuclear reactions]]. For countries who possess nuclear weapons see [[Nuclear powers]].

{{Taxobox_begin_placement | color = lightgreen}}

'''Nuclear power''' currently involves converting the nuclear energy of fissable uranium into thermal energy by fission, from thermal to kinetic energy by means of a [[steam turbine]] and finally to electron energy by a [[generator]]. [[Nuclear reactors]] currently use nuclear power to provide about 17% of the world's electricity and 7% of global energy. Opponents of nuclear power, including many [[environmental]] groups, such as the [[Union of Concerned Scientists]] [http://www.ucsusa.org/clean_energy/nuclear_safety/index.cfm ], argue against the use of nuclear power, often prefering [[renewable energy]], because of the unsolved problem of storing [[radioactive waste]], the potential for severe radioactive [[radioactive contamination|contamination]] by accident or sabotage, and the possibility that its use will lead to the [[nuclear proliferation|proliferation]] of [[nuclear weapons]] by some governments including, currently, Iran and in the past India, Israel, and Pakistan. The construction of new power plants abrubtly ended during the 1980's when efforts to conserve energy disrupted the projected growth for new energy demand. Much has occured since then to polarize the issue: the melt down of reactor #4 at [[Chernobyl]] in 1986, the discovery of global warming and its link to carbon dioxide, and increased competition for world oil reserves have led some to believe nuclear power is a part of a solution, while others see it as part of the problem. Some nuclear scientists claim the risks have been addressed with new technology and some Environmentalists believe nuclear power could safely reduce global warming because [[nuclear power plant]]s generate far fewer [[greenhouse gases]] than fossil fuel plants. After many years of lower than replacement rate construction, nuclear power plants are again poised for cautious growth.

{{Taxobox_regnum_entry | taxon = [[Plant]]ae}}

{{Taxobox_divisio_entry | taxon = [[Flowering plant|Magnoliophyta]]}}

{{Taxobox_classis_entry | taxon = [[Liliopsida]]}}

{{Taxobox_ordo_entry | taxon = '''Alismatales''' <small>Dumort. ([[1829]])</small>}}

{{Taxobox_end_placement}}

{{Taxobox_section_subdivision | color = lightgreen | plural_taxon = Families}}

[[Alismataceae]]<br/>

[[Aponogetonaceae]]<br/>

[[Araceae]]<br/>

[[Butomaceae]]<br/>

[[Cymodoceaceae]]<br/>

[[Hydrocharitaceae]]<br/>

[[Juncaginaceae]]<br/>

[[Limnocharitaceae]]<br/>

[[Posidoniaceae]]<br/>

[[Potamogetonaceae]]<br/>

[[Ruppiaceae]]<br/>

[[Scheuchzeriaceae]]<br/>

[[Tofieldiaceae]]<br/>

[[Zosteraceae]]

{{Taxobox_end}}

The order '''Alismatales''' contains the alismatids, a group of [[monocotyledon]]s (class [[Liliopsida]]). The order contains about 165 genera in 14 families, with cosmopolitic distribution. Most families are comprised of [[herb]]aceous non-[[succulent]] plants. These plants are commonly found in aquatic environmments. The [[flower]]s are usually arranged in [[inflorescence]]s, and the mature seeds lack [[endosperm]].

[[image:AKW-LeibstadtCH.jpg|frame|none|right|Nuclear power station at [[Leibstadt, Switzerland|Leibstadt]], [[Switzerland]]. The nuclear reactor is inside the dome-shaped [[containment building]].]]

Traditionally, the order Alismatales was restricted to contain just three families (Alismataceae, Butomaceae and Limnocharitaceae). The other families were not considered as alismatids, and were assigned to various distinct orders, but this approach produced [[polyphyletic]] groups, and so the whole group of families is now placed into a single order.

== History ==

The first successful experiment with [[nuclear fission]] was conducted in 1938 in [[Berlin]] by the German physicists [[Otto Hahn]], [[Lise Meitner]] and [[Fritz Strassman]].

The [[Petrosaviaceae]] have been placed in this order, but their actual affinity is not so clear. The alismatids have been considered the sister group of the [[Arales]] and the latter are now included here. As a result of this merger, the Araceae became the most important family in the order, accounting alone for over 2000 species in about 100 genera. The rest of families contain together just about 500 species.

During the [[World War II|Second World War]], a number of nations embarked on crash programs to develop nuclear energy, focusing first on the development of [[nuclear reactor]]s. The first self-sustaining [[nuclear chain reaction]] was obtained by [[Enrico Fermi]] in [[1943]], and reactors based on his research were used to produce the [[plutonium]] necessary for two of the [[nuclear weapon]]s (the "[[Trinity site|Trinity]]" device and the "[[Fat Man]]" weapon dropped on [[Atomic bombings of Hiroshima and Nagasaki|Nagasaki, Japan]]). Several nations began their own construction of nuclear reactors at this point, primarily for weapons use, though research was also being conducted into their use for civilian electricity generation.

== See also ==

Electricity was generated for the first time by a nuclear reactor on [[December 20]], [[1951]] at the [[EBR-I]] experimental station.

*[[Seagrass]]

== References ==

On [[June 27]], [[1954]], the world's first nuclear power plant that generated electricity for commercial use was officially connected to the [[Soviet Union|Soviet]] [[power grid]] at [[Obninsk]], [[USSR]]. The reactor was graphite moderated, water cooled and had a capacity of only 5 MW. The second reactor for commercial uses was [[Calder Hall]] in [[Sellafield]], [[England]] with a capacity of 45 MW. The [[Shippingport Reactor]] ([[Pennsylvania]]) was the first commercial nuclear generator to become operational in the [[United States]].

* [[Barthélemy Charles Joseph du Mortier|B. C. J. du Mortier]] (1829). ''Analyse des Familles de Plantes : avec l'indication des principaux genres qui s'y rattachent'', 54. Imprimerie de J. Casterman, Tournay.

In 1954, the chairman of the [[United States Atomic Energy Commission]] (forerunner of the US [[Nuclear Regulatory Commission]]) declared that nuclear power would be ''"too cheap to meter"'' [http://www.cns-snc.ca/media/toocheap/toocheap.html]. However, falling fossil fuel prices gradually made nuclear power less economically competitive during the 1980s (see also [[Oil price increases of 2004 and 2005]]). A popular movement against nuclear power also gained strength in the Western world, based on the fear of a possible [[nuclear accident]] and on fears of latent [[ionizing radiation|radiation]]. These, economic costs related to vastly extended construction times, and the accident at [[Three Mile Island]] in [[1979]], effectively stopped new plant construction in many countries. However it still continued strongly in many other countries, notably [[France]], [[Japan]], the former [[Soviet Union|USSR]] and now [[People's Republic of China|China]].

* W. S. Judd, C. S. Campbell, E. A. Kellogg, P. F. Stevens, M. J. Donoghue (2002). ''Plant Systematics: A Phylogenetic Approach, 2nd edition.'' pp. 242-247 (Alismatales). Sinauer Associates, Sunderland, Massachusets. ISBN 0878934030.

[[Category:Alismatales]]

In [[1986]], a large accident at the nuclear power plant at [[Chernobyl]], [[Ukraine]], exposed much of Europe to [[nuclear fallout]] and greatly heightened European concerns about nuclear power and nuclear safety. The units at the power plant, [[RBMK]]s, were unstable and had been built (as was normal in the [[Soviet Union]]) without [[containment building]]s around them.

[[da:Skeblad-ordenen (Alismatales)]]

== Current and planned use ==

[[de:Froschlöffelartige]]

In [[2000]], there were 438 commercial nuclear generating units throughout the world, with a total capacity of about 351 gigawatts.

[[es:Alismatales]]

[[fr:Alismatales]]

In [[2001]], the U.S. nuclear share of electricity generation was 19%. In [[2004]], there were 104 (69 pressurized water reactors, 35 boiling water reactors) commercial nuclear generating units licensed to operate in the United States, producing a total of 97,400 megawatts (electric), which is approximately 20 percent of the nation's total electric energy consumption. The United States is the world's largest supplier of commercial nuclear power.

[[he:&#1499;&#1507; &#1510;&#1508;&#1512;&#1491;&#1506; (&#1505;&#1491;&#1512;&#1492;)]]

[[pt:Alismatales]]

In [[France]], [[as of 2002]], 78% of all [[electric power]] was generated by nuclear reactors.

[[nl:Alismatales]]

[[no:Alismatales]]

[[Argentina]], [[Brazil]], [[Canada]], [[China]], [[Finland]], [[India]], [[Iran]], [[North Korea]], [[Russia]], [[Pakistan]], [[Japan]], [[South Korea]], [[Taiwan]], [[Ukraine]], and the U.S. ([[Browns Ferry]] and the [[Nuclear Power 2010 Program]]) are currently planning or building new nuclear reactors or reopening old ones. [[Bulgaria]], [[Czech Republic]], [[Egypt]], [[France]], [[Indonesia]], [[Israel]], [[Romania]], [[Slovakia]], [[South Africa]], [[Turkey]], and [[Vietnam ]] are considering doing this. [[Armenia]], [[Belgium]], [[Germany]], [[Hungary]], [[Lithuania]], [[Mexico]], [[Netherlands]], [[Slovenia]], [[Spain]], [[Sweden]], [[Switzerland]], and [[United Kingdom]] have nuclear reactors but currently no advanced proposals for expansion. [http://www.world-nuclear.org/info/inf17.htm] [http://www.world-nuclear.org/info/reactors.htm][http://www.wired.com/wired/archive/12.09/china.html].

According to the [[EIA]] and the [[IEA]], nuclear power is projected to have a slightly declining 5-10% share of world energy production until 2025, assuming that fossil fuel production can continue to expand rapidly, which is controversial. See [[Future energy development]].

==Reactor Types==

===Current Technology===

There are two types of nuclear power reactors in current use:

1. The [[nuclear reactor|nuclear fission reactor]] produces heat through a controlled [[nuclear chain reaction]] in a [[critical mass]] of [[fissile]] material.

All current [[nuclear power plant]]s are critical fission reactors, which are the focus of this article.

2. The [[radioisotope thermoelectric generator]] produces heat through passive [[radioactive decay]].

Some radioisotope thermoelectric generators have been created to power space probes (for example, the [[Cassini-Huygens|Cassini]] probe), some [[lighthouse]]s in the former [[Soviet Union]], and some [[pacemaker]]s.

===Experimental Technologies===

A number of other designs for nuclear power generation are the subject of active research and may be used for practical power generation in the future.

1. A number of advanced nuclear reactor designs could also make critical fission reactors much cleaner and safer. Typical new reactor designs have a construction time of three to four years [http://www.uic.com.au/nip16.htm].

2. [[Subcritical reactor]]s are designed to be safer and more stable, but pose a number of engineering and economic difficulties.

3. Controlled [[nuclear fusion]] could in principle be used in [[fusion power]] plants to produce safer, cleaner power, but significant scientific and technical obstacles remain. Several fusion reactors have been built, but as of yet none has produced more energy than it consumed. Despite research having started in the 1950s, no commercial fusion reactor is expected before 2050 [http://www.iter.org/index.htm]. The [[ITER]] project is currently the leading the effort to commercialize fusion power.

Nuclear power primarily produces concentrated [[heat]]. This can be converted to [[electricity]] and this currently constitutes a small but significant percentage of worldwide [[electricity generation]]. The heat can also be converted to mechanical work and this is the power source for many large military ocean going vessels (and a few commercial or government vessels). Other possible uses for the heat is in chemical processes, like in the production of [[hydrogen]], [[desalination]] [http://www.control.com.au/bi2003/articles242/feat2_242.shtml], or direct heating of houses.

== Fuel resources ==

[[Image:Fisherman on Lake Tanganyika.jpg|thumbnail|200px|The sun is a natural fusion reactor with an estimated remaining life of 5 billion years.]]

At the present use rate, there are 50 years left of low cost known [[uranium]] reserves [http://www.world-nuclear.org/info/inf75.htm]. Given that the cost of fuel is a minor cost factor for fission power, more expensive, lower grade, sources of uranium could be used in the future. For example: extraction from seawater [http://www.ans.org/pubs/journals/nt/va-144-2-274-278] or granite. Another alternative would be to use [[thorium]] as fission fuel. Thorium is three times more abundant in the Earth crust than uranium [http://www.world-nuclear.org/info/inf62.htm].

Current [[LWR|light water reactors]] burn the nuclear fuel poorly, leading to energy waste. [[Nuclear reprocessing]] [http://www.world-nuclear.org/info/inf04.htm] or burning the fuel better using different reactor designs would reduce the amount of waste material generated and allow better use of the available resources. As opposed to current light water reactors which use [[Uranium-235]] (0.7% of all natural uranium), [[fast breeder|fast breeder reactors]] use [[Uranium-238]] (99.3% of all natural uranium). It has been estimated that there is anywhere from 10,000 to five billion years (=remaining life of the Sun) worth of Uranium-238 for use in these power plants [http://www-formal.stanford.edu/jmc/progress/cohen.html]. Breeder technology has been used in several reactors [http://www.world-nuclear.org/info/inf08.htm].

Proposed fusion reactors assume the use [[deuterium]], an [[isotope]] of [[hydrogen]], as fuel and in most current designs also [[lithium]]. Assuming a fusion energy output equal to the current global ouput and that this does not increase in the future, then the known current lithium reserves would last 3000 years, lithium from sea water would last 60 million years, and a more complicated fusion process using only deuterium from sea water would have fuel for 150 billion years. [http://www.fusie-energie.nl/artikelen/ongena.pdf]

==Advantages==

Nuclear power provides steady energy at a consistent price without competing for resources from other countries. Nuclear generation does not produce carbon dioxide, sulfur dioxide, nitrogen oxides, mercury and other pollutants associated with the combustion of fossil fuels.

==Disadvantages==

Nuclear reactors require water to keep the reactor cool. The process of extracting energy from a heat source, called the [[Brayton cycle]], requires the steam to be cooled down. In practice, this means that on extremely hot days, which is when demand can be at its highest, the capacity of a nuclear plant may go down because the incoming water - usually a river - has been warmed so that the maximum allowed temperature for the exhaust water (which is lower than the fishkill temperature) is closer to the inlet temperature.

==Risks==

Opponents of nuclear power, like [[Greenpeace]], [[Sierra Club]][http://www.ge.com/ar2004/proxy/prop02.jsp ] and [[Friends_of_the_Earth|Friends Of The Earth]], argue against its use due to issues like the long term problems of storing [[radioactive waste]], the potential for severe [[radioactive contamination]] by an accident, and the possibility that its use will lead to the [[nuclear proliferation|proliferation]] of [[nuclear weapons]]. They point to the chequered history of nuclear power and its continual procession of [[List_of_nuclear_accidents|nuclear accidents]], from the 1950s to the present day.

Proponents argue that the risks are small and that fear has been the single largest obstacle to the widespread use of nuclear power. They believe that nuclear power or coal are currently the only realistic large scale energy sources that would be able to replace oil and natural gas after a peak in global oil and gas production has been reached (see [[peak oil]]). [[Coal]] currently contributes significantly to problems like [[global warming]], [[acid rain]], various diseases due to airborne pollution, and the storage of large amounts of [[ash]]. Renewables have not solved problems like intermittent output, high costs, and diffuse output which requires the use of large surface areas and much construction material and which increases distribution losses. For example, studies in Britain has shown that increasing windpower production contribution to 20% of all energy production would only reduce coal or nuclear power plant capacity by 6.7% (from 59 to 55 GWe) since they must remain as backup. Increasing the contribution of intermittent energy sources above that is not possible with current technology [http://www.world-nuclear.org/info/inf10.htm]. Future technology may both increase the efficiency and safety of alternative energy sources, including nuclear, and make them more environmentally friendly.

===Accident or attack===

Opponents argue that a major disadvantage of the use of nuclear reactors is the threat of a [[Nuclear_accidents|nuclear accident]] or terrorist attack and the possible resulting exposure to radiation. Proponents argue that the potential for a meltdown, as in [[Chernobyl accident]] is very small due to the care taken in designing adequate safety systems, and that the nuclear industry has much better statistics regarding humans deaths from occupational accidents than coal or hydropower [http://www.world-nuclear.org/info/inf06.htm]. The accident at Chernobyl is thought to have been caused by a combination of a faulty reactor design (such as no [[containment building]] present as in all Western reactors), poorly trained operators, and a non-existent safety culture. Even in an accident such as [[Three Mile Island]], the containment vessels were never breached, so that very little radiation was released into the environment.

In the [[US]], insurance for nuclear or radiological incidents is covered (except for facilities built after [[2002]]) by the [[Price-Anderson Act]] - in [[2005]], [[Congress of the United States|Congress]] will debate extending coverage to newer facilities. In the [[UK]], the [[Nuclear Installations Act]] of 1965 governs liability for nuclear damage for which a UK nuclear licensee is responsible. The [[Vienna Convention on Civil Liability for Nuclear Damage]] puts in place an international framework for nuclear liability.

Research is being done to lessen the risks by developing automated and [[passively safe]] fission reactors. Fusion reactors have little risk since the fuel contained in the reaction chamber is only enough to sustain the reaction for about a minute, whereas a fission reactor contains about a year's supply of fuel. Subcritical reactors never have a self sustained nuclear chain reaction.

Opponents of nuclear power express concerns that nuclear waste is not well protected, and that it can be released in the event of terrorist attack. Other energy sources like, hydropower plants and [[liquified natural gas]] [[tankers]], are also vulnerable to accidents attacks. Proponents of nuclear power contend, however, that nuclear waste ''is'' well protected, and state their argument that there has been no accident involving any form of nuclear waste from a civilian program worldwide. In addition, they point to large studies carried out by NRC and other agencies that tested the robustness of both reactor and waste fuel storage, and found that they should be able to sustain a terrorist attack comparable to the [[September 11, 2001 attacks|September 11]] terrorist attacks [http://www.world-nuclear.org/news/resistance.htm]. Spent fuel is usually housed inside the reactor [[containment building]] [http://www.world-nuclear.org/info/inf03.htm].

According to the [[Nuclear Regulatory Commission]], 20 American States have requested emergency doses of potassium iodine which the NRC recommends for those living within 10 miles of a nuclear power plant [http://www.nrc.gov/what-we-do/emerg-preparedness/protect-public/potassium-iodide.html].

The United States Navy owns and operates half of the nuclear reactors in the world. There has never been an incident in 51 years of near constant naval operation of these hundreds of power plants.

=== Airborne pollution ===

All power sources, including renewables, contribute to [[global warming]], for example when mining and refining raw materials. However, most life cycle analysis shows that nuclear power contribution is about equal to that of many renewables and is much less than that from fossil fuels. [http://www.world-nuclear.org/info/inf11.htm]. Fission reactors produce gases such as [[iodine]]-131 or [[krypton]]-85 which have to be stored on-site for several half-lives until they have decayed to levels officially regarded as safe. According to several independent organizations, a person receives more radioactivity from household appliances than from nuclear power [http://www.world-nuclear.org/education/ne/ne6.htm].

=== Health effect on population near nuclear power plants ===

Most of the human exposure to radiation comes from natural [[background radiation]]. Most of the remaining exposure comes from medical procedures. Several large studies in the US, Canada, and Europe have found no evidence of any increase in cancer mortality among people living near nuclear facilities. For example, in 1990, the [[National Cancer Institute]] (NCI) of the [[National Institutes of Health]] announced that a large-scale study, which evaluated mortality from 16 types of cancer, found no increased incidence of cancer mortality for people living near 62 nuclear installations in the United States. The study showed no increase in the incidence of childhood leukemia mortality in the study of surrounding counties after start-up of the nuclear facilities. The NCI study, the broadest of its kind ever conducted, surveyed 900,000 cancer deaths in counties near nuclear facilities.

However, in Britain there are elevated childhood leukemia levels near some industrial facilities, particularly near [[Sellafield]], where children living locally are ten times more likely to contract the cancer. The reasons for these increases, or clusters, are unclear, but one study of those near Sellafield has ruled out any contribution from nuclear sources. Apart from anything else, the levels of radiation at these sites are orders of magnitude too low to account for the excess incidences reported. One explanation is viruses or other infectious agents being introduced into a local community by the mass movement of migrant workers. Likewise, small studies have found an increased incidence of childhood leukemia near some nuclear power plants has also been found in Germany [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9210727] and France [http://www.ieer.org/ensec/no-4/lahague.html]. Nonetheless, the results of larger multi-site studies in these countries invalidate the hypothesis of an increased risk of leukaemia related to nuclear discharge. The methodology and very small samples in the studies finding an increased incidence has been criticized. [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11990512&dopt=Abstract]

[http://www.nei.org/doc.asp?catnum=3&catid=1112&docid=&format=print]

[http://www.world-nuclear.org/info/inf05.htm]

[http://www.personalmd.com/news/n0818103222.shtml].

=== Solid waste ===

''Main article: [[Nuclear waste]]

Nuclear power produces spent fuel, a unique solid waste problem. Because spent nuclear fuel is radioactive, extra care and forethought are given to facilitate their safe storage (see [[nuclear waste]]). The waste from highly radioactive spent fuel needs to be handled with great care and forethought due to the long [[half-life]]s of the radioactive [[isotope]]s in the waste.

[[As of 2003]], the [[United States]] accumulated about 49,000 metric tons of spent nuclear fuel from nuclear reactors. Unlike other countries, U.S. policy forbids recycling of used fuel and is treated as waste. After 10,000 years of radioactive decay, according to [[United States Environmental Protection Agency]] standards, the spent nuclear fuel will no longer pose a threat to public health and safety. It is unclear whether this material can be safeguarded for such a long period of time.

The safe storage and disposal of nuclear waste is a difficult challenge. Because of potential harm from radiation, spent nuclear fuel must be stored in shielded basins of water, or in dry storage vaults or containers until its radioactivity decreases naturally ("decays") to safe levels. This can take days or thousands of years, depending on the type of fuel. Most waste is currently stored in temporary storage sites, requiring constant maintenance, while suitable permanent disposal methods are discussed. Underground storage like [[Yucca Mountain]] in U.S. has been proposed as permanent storage. Some argue that the generation of nuclear waste outpaces the ability of the current temporary storage sites to safely store it [http://www.latimes.com/news/nationworld/nation/la-na-waste12jun12,0,7666923.story?coll=la-home-headlines]. See the article on the [[nuclear fuel cycle]] for more information.

The nuclear industry produces a much greater volume of low-level radioactive waste in the form of contaminated items like clothing, hand tools, water purifier resins, and upon decomissioning the materials of which the reactor itself is built. In the United States, the [[Nuclear Regulatory Commission]] has repeatedly attempted to allow low-level materials to be handled as normal waste: landfilled, recycled into consumer items, etc. Much low-level waste release very low levels of radioactivity and is essentially considered radioactive waste because of its history. For example, according to the standards of the NRC, the radiation released by coffee is enough to treat it as low level waste. Overall, nuclear power produces far less waste material than fossil-fuel based power plants. [[Coal]]-burning plants are particularly noted for producing large amounts of radioactive ash due to concentrating naturally occurring radioactive material in the coal.

In addition, the nuclear industry fuel cycle produces many tons of depleted uranium (uranium from which the easily fissile U235 element has been removed, leaving behind only U238). This material is much more concentrated than natural uranium ores, and must be disposed of. U238 is a very tough metal with several commercial uses, for example aircraft production and radiation shielding. Nuclear power has useful additional advantages, including production of [[radioisotopes]] used in medicine and food preservation, though the demand for these products can be satisfied by a relatively small number of plants.

In countries with nuclear power, radioactive wastes comprise less than 1% of total industrial toxic wastes (which remains hazardous indefinitely) [http://www.world-nuclear.org/info/inf04.htm].

The amounts of waste can be reduced in several ways. Both [[nuclear reprocessing]] and [[fast breeder reactor]]s can reduce the amounts of waste and increase the amount of energy gained per fuel unit. [[Subcritical reactor]]s or fusion reactors could greatly reduce the time the waste has to be stored [http://www.world-nuclear.org/info/inf35.htm]. Subcritical reactors may also be able to do the same already existing waste. It has been argued that the best solution for the nuclear waste is above ground temporary storage since technology is rapidly changing. The current waste may well become valuable fuel in the future, particularly if it is not reprocessed, as in the U.S.

=== Nuclear proliferation ===

''Main article: [[Nuclear proliferation]]''

[[Image:Nagasakibomb.jpg|thumbnail|200px|Both nuclear fission and nuclear fusion can be used for military purposes. See [[Nuclear weapons]].]]

Opponents of nuclear power point out that nuclear technology is often [[dual-use technology|dual-use]], and much of the same materials and knowledge used in a civilian nuclear program can be used to develop [[nuclear weapons]]. This concern is known as nuclear proliferation and is a major reactor design criterion.

The military and civil purposes for nuclear energy are intertwined in most countries with nuclear capabilities. in the US for example the mission statement of the department of energy states its two primary goals:

:"''1) Ensuring a dependable energy supply for the American economy; 2) ensuring a secure, reliable nuclear deterrent for the nation&#8217;s defense.''"[http://www.gpoaccess.gov/usbudget/fy04/pdf/budget/energy.pdf ]

While the enriched uranium used in most nuclear reactors is not concentrated enough to build a bomb (most nuclear reactors run on 4% enriched uranium, while a bomb requires an estimated 90% enrichment), the technology used to enrich uranium could be used to make the highly enriched uranium needed to build a bomb. In addition, [[breeder reactor]] designs such as [[CANDU]] can be used to generate [[plutonium]] for bomb making materials. It is believed that the nuclear programs of India and Pakistan used CANDU-like reactors to produce fissionable materials for their weapons.

To prevent this, safeguards on nuclear technology were published in the [[Nuclear Non-Proliferation Treaty]] (NPT) and monitored by the [[International Atomic Energy Agency]] (IAEA) of [[1968]].Nations signing the treaty are required to report to the IAEA what nuclear materials they hold and their ___location. They agree to accept visits by IAEA auditors and inspectors to verify independently their material reports and physically inspect the nuclear materials concerned to confirm physical inventories of them in exchange for access to nuclear materials and equipment on the global market.

Several states did not sign the treaty and were able to use international nuclear technology (often procured for civilian purposes) to develop nuclear weapons ([[India]], [[Pakistan]], [[Israel]], and [[South Africa]]). Of those who have signed the treaty and received shipments of nuclear paraphernalia, many states have either claimed to or been accused of attempting to use supposedly civilian nuclear power plants for developing weapons, including [[Iran]] and [[North Korea]]. Certain types of reactors are more conducive to producing nuclear weapons materials than others, and a number of international disputes over proliferation have centered on the specific model of reactor being contracted for in a country suspected of nuclear weapon ambitions.

New technology, like [[SSTAR]], may lessen the risk of nuclear proliferation by providing sealed reactors with a limited self-contained fuel supply and with restrictions against tampering.

Some proponents of nuclear power agree that the risk of nuclear proliferation may be a reason to prevent nondemocratic developing nations from gaining any nuclear technology but argue that this is no reason for democratic developed nations to abandon their nuclear power plants. Especially since it seems that democracies never make war against each other (See the [[democratic peace theory]]). Furthermore, all power sources and technology can be used to produce and use weapons. The [[weapons of mass destruction]] used in [[chemical warfare]] and [[biological warfare]] are not dependent on nuclear power. Humans could still make war even if all technology was forbidden.

== Economy ==

Opponents of nuclear power claim that any of the environmental benefits are outweighed by safety compromises and by the costs related to construction and operation of nuclear power plants, including costs for spent-fuel disposition and plant retirement. Proponents of nuclear power state that nuclear energy is the only power source which explicitly factors the estimated costs for waste containment and plant decommissioning into its overall cost, and that the quoted cost of fossil fuel plants is deceptively low for this reason. The cost of many renewables would be increased if they included necessary back-up due to their intermittent nature. Also not included in costs, hydropower produces large amount of greenhouse gases when organic matter decomposes in the dams [http://www.springerlink.com/app/home/contribution.asp?wasp=aeab79d7983d4a8995b9beb2f22ffeb4&referrer=parent&backto=issue,5,25;journal,29,89;linkingpublicationresults,1:100344,1]

A UK Royal Academy of Engineering report in 2004 looked at electricity generation costs from new plant in the UK. In particular it aimed to develop "a robust approach to compare directly the costs of intermittent generation with more dependable sources of generation". This meant adding the cost of standby capacity for wind, as well as carbon values up to £30 per tonne CO2 (£110/tC) for coal and gas. Wind power was shown to be more than twice as expensive as nuclear power. Without a carbon tax, coal, nuclear and gas ranged 2.2-2.6 p/kWh and coal gasification was 3.2 p/kWh - all base-load plant. Adding the carbon tax (up to 2.5 p) took coal close to onshore wind (with back-up) at 5.4 p/kWh - offshore wind is 7.2 p/kWh, while nuclear remained at 2.3 p/kWh. Nuclear figures included decommissioning. [http://www.world-nuclear.org/info/inf02.htm].

Proponents note that several opponents of nuclear power have been forced to conclude in studies that renewables cannot replace all current energy production from fossil fuels, due to issues like intermittent output. To accept nuclear power may be a better solution than the lower livings standards some argue for [http://sharpgary.org/RenewableE.html][http://scholar.google.com/url?sa=U&q=http://www.inderscience.com/filter.php%3Faid%3D2383].

===Capital costs===

In the U.S, a single nuclear power plant is significantly more expensive to build than a single steam-based coal-fired plant. A coal plant is itself more expensive to build than a single natural gas-fired combined-cycle plant. Although the cost per megawatt for a nuclear power plant is comparable to a coal-fired plant and less than a natural gas plant, the smallest nuclear power plant that can be built is much larger than the smallest natural gas power plant, making it possible for a utility to build natural gas plants in much smaller increments.

In the U.S., licensing, inspection and certification delays add large amounts of time and cost to the construction of a nuclear plant. These delays and costs are not present when building either gas-fired or coal-fired plants. Because a power plant does not earn money during construction, longer construction times translate directly into higher interest charges on borrowed construction funds. However, the regulatory processes for siting, licensing, and constructing have since been standardized, to make construction of newer and inherently safer designs more attractive to utilities and their investors.

In Japan and France, construction costs and delays are significantly less because of streamlined government licensing and certification procedures. In France, one model of reactor was type-certified, using a [[safety engineering]] process similar to the process used to certify aircraft models for safety. That is, rather than licensing individual reactors, the regulatory agency certified a particular design and its construction process to produce safe reactors. U.S. law permits type-licensing of reactors, but no type license has ever been issued by a U.S. nuclear regulatory agency.

In an attempt to encourage development of nuclear power, under the [[Nuclear Power 2010 Program]] the US Department of Energy (DOE) has offered interested parties the opportunity to introduce France's model for licensing and to subsidize 50% of the construction expenses. Several applications were made but the project is still in its infancy.

===Operating costs===

In the U.S., these charges require that coal and nuclear power plants must operate more cheaply than natural gas plants in order to be built. In general, coal and nuclear plants have the same operating costs (operations and maintenance plus fuel costs). However, nuclear and coal differ in the source of those costs. Nuclear has lower fuel costs but higher operating and maintenance costs than coal. In recent times in the United States these operating costs have not been low enough for nuclear to repay its high investment costs. Thus new nuclear reactors have not been built in the United States. Coal's operating cost advantages have only rarely been sufficient to encourage the construction of new coal based power generation. Around 90 to 95 percent of new power plant construction in the United States has been natural gas-fired. These numbers exclude capacity expansions at existing coal and nuclear units.

To be competative in the current market, both the nuclear and coal industries must reduce new plant investment costs and construction time. The burden is clearly greater for nuclear producers than for coal producers, because investment costs are higher for nuclear plants, which also have the same operating costs. Operation and maintenance costs are particularly important because they represent a large portion of costs for nuclear power.

===Subsidies===

Energy research and development (R&D) for nuclear power has and continues to receive much larger state subsidies than R&amp;D for renewable energy or fossil fuels. However, today most of this takes places in Japan and France: in most other nations renewable R&D get more money. In the U.S., public research money for nuclear fission declined from 2179 to 35 million dollars between 1980 to 2000 [http://www.world-nuclear.org/info/inf68.htm].

Renewables receive large direct production subsidies and tax breaks in many nations [http://www.world-nuclear.org/info/inf68.htm]. Fossil fuels receive large indirect subsidies since they do not have to pay for their pollution and in various other ways [http://www.ucsusa.org/publications/report.cfm?publicationID=149].

In the [[US]] the nuclear industry has limited liability for accidents (9.5 billion dollars as of [[2004]]) under the [[Price-Anderson Act]] - although [[Congress of the United States|Congress]] could later assess more. This is often termed a subsidy.

===Other economic issues===

Nuclear Power plants tend to be most competitive in areas where no other resources are readily available. China and India top the list of new plant starts. France, most notably, has almost no native supplies of fossil fuels [http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/french.html]. The province of [[Ontario, Canada]] is already using all of its best sites for hydroelectric power, and has minimal supplies of fossil fuels, so a number of nuclear plants have been built there. Conversely, in the [[United Kingdom]], according to the government's Department Of Trade And Industry, no further nuclear power stations are to be built, due to the high cost per unit of nuclear power, compared to fossil fuels [http://www.dti.gov.uk/nuclear/nuclear.htm]. However, the British government's chief scientific advisor [[David King]] reports that building one more generation of nuclear power plants may be necessary [http://washingtontimes.com/upi-breaking/20050512-082200-3520r.htm].

Most new gas-fired plants are intended for peak supply. The larger nuclear and coal plants cannot quickly adjust their instantaneous power production, and are generally intended for baseline supply. The market price for baseline power has not increased as rapidly as that for peak demand. Some new experimental reactors, notably [[pebble bed modular reactor]]s, are specifically designed for peaking power.

Any effort to construct a new nuclear facility, whether it is a older design or a newer experimental design, around the world must deal with [[NIMBY]] and [[NIABY]] objections. Given the high profile of both the Three Mile Island and Chernobyl accidents, few municipalities welcome a new nuclear reactor, processing plant, transportation route, or experimental nuclear burial ground within their borders, and many have issued local ordinances prohibiting the development of nuclear power. However, a few U.S. areas with nuclear units are campaigning for more (see [[Nuclear Power 2010 Program]]).

Current nuclear reactors returns around 40-60 times the invested energy when using life cycle analysis. This is better than coal, natural gas, and current renewables except hydropower [http://www.world-nuclear.org/info/inf11.htm].

==List of atomic energy groups==

* [[American Nuclear Society]] (United States)

* [[Department of Energy]] (United States)

* [[Areva]] (France)

* [[Électricité de France|EDF]] (France)

* [[MinAtom]] (Russia)

* [[EnergoAtom]] (Ukraine)

* [[Egyptian Atomic Energy Authority]]

* [[United Kingdom Atomic Energy Authority]] (UKAEA)

*[[EURATOM]] (Europe)

*[[International Atomic Energy Agency]] (IAEA)

==References==

* [http://www.sandia.gov/LabNews/LN03-26-99/savannah_story.htm Atoms for Peace]

*[http://www.phyast.pitt.edu/~blc/book/BOOK.html The Nuclear Energy Option], online book by Bernard L. Cohen. Pro nuclear power. Emphasis on risk estimates of nuclear.

==External links==

* [http://www.westinghousenuclear.com Westinghouse Electric Co.]

* [http://www.areva.com Areva (and Framatone)]

* [http://www.world-nuclear.org/index.htm World Nuclear Association]

* [http://archive.greenpeace.org/comms/nukes/chernob/rep02.html Calendar of Nuclear Accidents]

* [http://www.antenna.nl/wise/index.html World Information Service on Energy (WISE)]

==See also==

*[[Atoms for Peace]]

*[[Fusion power]]

*[[Nuclear physics]]

*[[Future energy development]]

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