Nuclear marine propulsion: Difference between revisions
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{{short description|Propulsion system for marine vessels utilizing a nuclear powerplant}} |
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'''Nuclear marine propulsion''' is propulsion of a Merchant ship powered by a [[nuclear reactor]]. '''Naval Nuclear Propulsion''' is propulsion that specifically refers to naval warships (see [[Nuclear navy]]). |
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[[File:50 Let Pobedy.jpg|thumb|right|When the nuclear-powered {{sclass|Arktika|icebreaker|4}} ''[[50 Let Pobedy]]'' was put into service in 2007, it became the world's largest [[icebreaker]].]] |
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'''Nuclear marine propulsion''' is [[Marine propulsion|propulsion of a ship]] or submarine with heat provided by a [[nuclear reactor]]. The power plant heats water to produce steam for a turbine used to turn the ship's [[propeller]] through a [[Transmission (mechanics)|gearbox]] or through an electric generator and motor. Nuclear propulsion is used primarily within naval warships such as [[nuclear submarines]] and [[supercarrier]]s. A small number of experimental civil nuclear ships have been built.<ref>{{cite book |first=John G |last=Wirt |chapter=A Federal Demonstration Project: N.S. Savannah |title=Innovation in the maritime industry |volume=1 |publisher=National Academies, for Maritime Transportation Research Board, National Research Council (U.S.) |year=1979 |pages=29–36}}</ref> |
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Compared to oil- or coal-fuelled ships, nuclear propulsion offers the advantage of very long intervals of operation before refueling. All the fuel is contained within the nuclear reactor, so no cargo or supplies space is taken up by fuel, nor is space taken up by exhaust stacks or combustion air intakes.<ref name="auto1">{{Cite web|url=https://enseccoe.org/data/public/uploads/2021/10/d1_the-future-role-of-nuclear-propulsion-in-the-military.pdf|title=The Future Role of Nuclear Propulsion in the Military|last=Trakimavičius|first=Lukas|website=NATO Energy Security Centre of Excellence|language=en|access-date=2021-10-15}}</ref> The low fuel cost is offset by high operating costs and investment in infrastructure, however, so nearly all nuclear-powered vessels are military.<ref name="auto1">{{Cite web|url=https://enseccoe.org/data/public/uploads/2021/10/d1_the-future-role-of-nuclear-propulsion-in-the-military.pdf|title=The Future Role of Nuclear Propulsion in the Military|last=Trakimavičius|first=Lukas|website=NATO Energy Security Centre of Excellence|language=en|access-date=2021-10-15}}</ref> |
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==History== |
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==Power plants== |
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Work on nuclear marine propulsion started in the [[1940s]], and the first test reactor started up in the [[United States of America|United States]] in [[1953]]. The first nuclear-powered [[submarine]], [[USS Nautilus (SSN-571)|USS ''Nautilus'']], put to sea in [[1955]]. |
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===Basic operation of naval ship or submarine=== |
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This marked the transition of submarines from slow underwater vessels to warships capable of sustaining 20-25 [[Knot (speed)|knot]]s (37-46 km/h) submerged for weeks on end. The submarine had come into its own. |
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Most naval nuclear reactors are of the [[Pressurized water reactor|pressurized water]] type, with the exception of a few{{quantify|date=October 2023}} attempts{{by who|date=October 2023}} at using liquid sodium-cooled reactors.<ref name="auto1">{{Cite web|url=https://enseccoe.org/data/public/uploads/2021/10/d1_the-future-role-of-nuclear-propulsion-in-the-military.pdf|title=The Future Role of Nuclear Propulsion in the Military|last=Trakimavičius|first=Lukas|website=NATO Energy Security Centre of Excellence|language=en|access-date=2021-10-15}}</ref> A primary water circuit transfers heat generated from [[nuclear fission]] in the fuel to a [[steam generator (nuclear power)|steam generator]]; this water is kept under pressure so it does not boil. This circuit operates at a temperature of around {{convert|250|to|300|C}}. Any [[radioactive contamination]] in the primary water is confined. Water is circulated by pumps; at lower power levels, reactors designed for submarines may rely on natural circulation of the water to reduce noise generated by the pumps.{{citation_needed|date=August 2019}} |
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''Nautilus'' led to the parallel development of further ([[Skate class submarine|''Skate''-class]]) submarines, powered by single reactors, and an aircraft carrier, [[USS Enterprise (CVN-65)|''Enterprise'']], powered by eight reactor units in [[1960]]. A cruiser, [[USS Long Beach (CGN-9)|''Long Beach'']], followed in [[1961]] and was powered by two of these early units. Remarkably, ''Enterprise'' remains in service. |
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The hot water from the reactor heats a separate water circuit in the steam generator. That water is converted to steam and passes through [[steam drier]]s on its way to the [[steam turbine]]. Spent steam at low pressure runs through a [[condenser (heat transfer)|condenser]] cooled by seawater and returns to liquid form. The water is pumped back to the steam generator and continues the cycle. Any water lost in the process can be made up by [[Desalination|desalinated]] sea water added to the steam generator feed water.<ref>Viren Chopra, Rob Houston (ed), ''DK Eyewitness Books: Transportation'', Penguin, 2012, {{ISBN|1465408894}} page 60</ref> |
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By [[1962]] the [[United States Navy|U.S. Navy]] had 26 nuclear submarines operational and 30 under construction. Nuclear power had revolutionized the Navy. |
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In the turbine, the steam expands and reduces its pressure as it imparts energy to the rotating blades of the turbine. There may be many stages of rotating blades and fixed guide vanes. The output shaft of the turbine may be connected to a gearbox to reduce rotation speed, then a shaft connects to the vessel's propellers. In another form of drive system, the turbine turns an electrical generator, and the electric power produced is fed to one or more drive motors for the vessel's propellers. The [[Russian Navy|Russian]], [[United States Navy|U.S.]] and [[Royal Navy|British]] navies rely on direct steam turbine propulsion, while French and Chinese ships use the turbine to generate electricity for propulsion ([[turbo-electric transmission]]).{{citation_needed|date=August 2019}} |
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The technology was shared with the [[United Kingdom]], while [[France|French]], [[Soviet Union|Soviet]], and [[China|Chinese]] developments proceeded separately. |
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Some nuclear submarines have a single reactor, but Russian submarines have two, and so had {{USS|Triton|SSRN-586|6}}. Most American aircraft carriers are powered by two reactors, but {{USS|Enterprise|CVN-65|6}} had eight. The majority of marine [[Nuclear reactor|reactors]] are of the [[Pressurized water reactor|pressurized water]] type, although the U.S. and Soviet navies have designed warships powered with [[liquid metal cooled reactor]]s.{{citation_needed|date=August 2019}} |
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After the ''Skate''-class vessels, reactor development proceeded and in the USA a single series of standardised designs was built by both [[Westinghouse Electric Corporation|Westinghouse]] and [[General Electric]], one reactor powering each vessel. [[Rolls-Royce plc|Rolls Royce]] built similar units for [[Royal Navy]] submarines and then developed the design further to the PWR-2. |
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===Differences from land power plants=== |
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The largest submarines are the 26,500 tonne Russian [[Typhoon class submarine|Typhoon class]]. |
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Marine-type reactors differ from land-based commercial electric power reactors in several respects.{{citation_needed|date=August 2019}} |
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While land-based reactors in nuclear power plants produce up to around 1600 megawatts of net electrical power (the [[nameplate capacity]] of the [[EPR (nuclear reactor)|EPR]]), a typical marine propulsion reactor produces no more than a few hundred megawatts. Some [[small modular reactor]]s (SMR) are similar to marine propulsion reactors in capacity and some design considerations and thus nuclear marine propulsion (whether civilian or military) is sometimes proposed as an additional market niche for SMRs. Unlike for land-based applications where hundreds of hectares can be occupied by installations like [[Bruce Nuclear Generating Station]], at sea tight space limits dictate that a marine reactor must be physically small, so it must generate higher power per unit of space. This means its components are subject to greater stresses than those of a land-based reactor. Its mechanical systems must operate flawlessly under the adverse conditions encountered at sea, including vibration and the pitching and rolling of a ship operating in rough seas. Reactor shutdown mechanisms cannot rely on gravity to drop control rods into place as in a land-based reactor that always remains upright. Salt water corrosion is an additional problem that complicates maintenance.{{citation_needed|date=August 2019}} |
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==Civil vessels== |
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[[File:Nuclear fuel element.jpg|thumb|A nuclear fuel element for the cargo ship {{ship|NS|Savannah}}. The element contains four bundles of 41 fuel rods. The uranium oxide is enriched to 4.2 and 4.6 percent U-235]] |
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Development of nuclear merchant ships began in the [[1950s]] but has not been commercially successful. The US-built [[NS Savannah|NS ''Savannah'']], was commissioned in [[1962]] and decommissioned eight years later. It was a technical success, but not economically viable. The German-built ''[[Otto Hahn (ship)|Otto Hahn]]'' cargo ship and research facility sailed some 650,000 nautical miles on 126 voyages in 10 years without any technical problems. However, it proved too expensive to operate and was converted to diesel. |
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As the core of a seagoing reactor is much smaller than a power reactor, the probability of a neutron intersecting with a fissionable nucleus before it escapes into the shielding is much lower. As such, the fuel is typically more highly enriched (i.e., contains a higher concentration of <sup>235</sup>U vs. <sup>238</sup>U) than that used in a land-based nuclear power plant, which increases the probability of fission to the level where a sustained reaction can occur. Some marine reactors run on relatively low-enriched [[uranium]], which requires more frequent refueling. Others run on [[highly enriched uranium]], varying from 20% <sup>235</sup>U, to the over 96% <sup>235</sup>U found in U.S. [[submarine]]s,<ref>{{cite web |url=http://www.nti.org/e_research/e3_74.html |title=Global Submarine Proliferation: Emerging Trends and Problems |first=James Clay |last=Moltz |publisher=[[NTI]] |date=March 2006 |access-date=2007-03-07 |archive-url=https://web.archive.org/web/20070209223424/http://www.nti.org/e_research/e3_74.html |archive-date=2007-02-09 |url-status=dead }}</ref> in which the resulting smaller core is quieter in operation (a big advantage to a submarine).<ref>{{cite web |url= http://www.armscontrolwonk.com/1738/silence-is-highly-enriched-uranium |title=Silence is highly enriched uranium |date=December 13, 2007 |first=James |last=Acton |access-date=2007-12-13}}</ref> Using more-highly enriched fuel also increases the reactor's power density and extends the usable life of the nuclear fuel load, but is more expensive and a greater risk to [[nuclear proliferation]] than less-highly enriched fuel.<ref name="ANTIENRICHED">{{cite web |title=Ending the Production of Highly Enriched Uranium for Naval Reactors |work=James Martin Center for Nonproliferation Studies |url= http://cns.miis.edu/npr/pdfs/81mahip.pdf |access-date=September 25, 2008}}</ref> |
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The Japanese ''[[Mutsu (ship)|Mutsu]]'' was the third civil vessel. It was dogged by technical and political problems and was an embarrassing failure. These three vessels used reactors with low-enriched uranium fuel. |
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A marine nuclear propulsion plant must be designed to be highly reliable and self-sufficient, requiring minimal maintenance and repairs, which might have to be undertaken many thousands of miles from its home port. One of the technical difficulties in designing fuel elements for a seagoing nuclear reactor is the creation of fuel elements that will withstand a large amount of radiation damage. Fuel elements may crack over time and gas bubbles may form. The fuel used in marine reactors is a metal-[[zirconium]] alloy rather than the ceramic UO<sub>2</sub> ([[uranium dioxide]]) often used in land-based reactors. Marine reactors are designed for long core life, enabled by the relatively high enrichment of the uranium and by incorporating a "[[Neutron_poison#Burnable_poisons|burnable poison]]" in the fuel elements, which is slowly depleted as the fuel elements age and become less reactive. The gradual dissipation of the "nuclear poison" increases the reactivity of the core to compensate for the lessening reactivity of the aging fuel elements, thereby extending the usable life of the fuel. The compact [[Reactor vessel|reactor pressure vessel]] is provided with an internal [[neutron]] shield, which reduces the damage to the steel from constant neutron bombardment.{{citation_needed|date=August 2019}} |
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In contrast, nuclear propulsion has proven both technically and economically feasible in the [[Soviet Union|Soviet]] [[Arctic]]. The power levels and energy required for icebreaking, coupled with refueling difficulties for other types of vessels, are significant factors. The [[icebreaker]] [[Soviet icebreaker Lenin|''Lenin'']] was the world's first nuclear-powered surface vessel and remained in service for 30 years, though new reactors were fitted in [[1970]]. It led to a series of larger icebreakers, the 23,500 dwt [[Arktika class icebreaker|''Arktika''-class]], launched from [[1975]]. These vessels have two reactors and are used in deep Arctic waters. ''Arktika'' was the first surface vessel to reach the [[North Pole]]. |
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==Decommissioning== |
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For use in shallow waters such as estuaries and rivers, shallow-draft [[Taymyr class icebreaker|''Taymyr''-class icebreakers]] with one reactor are being built in [[Finland]] and then fitted with their nuclear steam supply system in [[Russia]]. They are built to conform with international safety standards for nuclear vessels. |
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Decommissioning nuclear-powered submarines has become a major task for U.S. and Russian navies.<ref>Sarkisov and Tournyol du Clos (1999), p. 3.</ref> After defuelling, U.S. practice is to cut the reactor section from the vessel for disposal in shallow land burial as low-level waste (see the ''[[ship-submarine recycling program]]'').<ref>Sarkisov and Tournyol du Clos (1999), p. 3-4.</ref> In Russia, whole vessels, or sealed reactor sections, typically remain stored afloat, although a new facility near [[Sayda Bay]] is to provide storage in a concrete-floored facility on land for some submarines in the far north.{{citation_needed|date=August 2019}} |
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==Future designs== |
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* See also: [[List of Civilian Nuclear Ships]] |
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Russia built a [[Russian floating nuclear power station|floating nuclear power plant]] for its far eastern territories. The design has two 35 MWe units based on the [[KLT-40 reactor]] used in [[icebreaker]]s (with refueling every four years). Some Russian naval vessels have been used to supply electricity for domestic and industrial use in remote far eastern and Siberian towns.{{citation_needed|date=August 2019}} |
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In 2010, [[Lloyd's Register]] was investigating the possibility of civilian nuclear marine propulsion and rewriting draft rules (see text under ''Merchant Ships'').<ref name="wnnLL">{{Citation | url = http://www.world-nuclear-news.org/NN_Full_steam_ahead_for_nuclear_shipping_1811101.html | title = Full steam ahead for nuclear shipping | newspaper = World Nuclear News | date = 18 November 2010 | access-date = 27 November 2010}}.</ref><ref name="Hirdaris 101–130">{{cite journal|last1 = Hirdaris |first1 =Spyros| first2 =YF | last2 = Cheng | first3 = P | last3 = Shallcross | first4 = J | last4 = Bonafoux | first5 = D | last5 = Carlson | first6 = B | last6 = Prince | first7 = GA | last7 = Sarris|title=Considerations on the potential use of Nuclear Small Modular Reactor (SMR) technology for merchant marine propulsion|journal=Ocean Engineering|date=15 March 2014|volume=79|pages=101–130|doi=10.1016/j.oceaneng.2013.10.015}}</ref><ref name="Hirdaris A37-A60">{{cite journal| last1 = Hirdaris | first1 = Spyros| first2 = YF | last2 = Cheng | first3 = P | last3 = Shallcross | first4 = J | last4 = Bonafoux | first5 = D | last5 = Carlson | first6 = B | last6 = Prince | first7 = GA | last7 = Sarris | title = Concept Design for a Suezmax Tanker Powered by a 70 MW Small Modular Reactor|journal=Transactions of the Royal Institution of Naval Architects Part A: International Journal of Maritime Engineering|date=March 2014|volume=156|issue=A1|pages =A37–A60|doi= 10.3940/rina.ijme.2014.a1.276}}</ref> |
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==Power plants== |
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==Civil liability== |
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Naval reactors are pressurized water types, which differ from commercial reactors producing electricity in that: |
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Insurance of nuclear vessels is not like the insurance of conventional ships. The consequences of an accident could span national boundaries, and the magnitude of possible damage is beyond the capacity of private insurers.<ref>{{cite web |url= http://www.world-nuclear.org/info/inf67.html |title=Liability for Nuclear Damage |publisher=World Nuclear Association |access-date=March 17, 2011}}</ref> A special international agreement, the ''Brussels Convention on the Liability of Operators of Nuclear Ships'', developed in 1962, would have made signatory national governments liable for accidents caused by nuclear vessels under their flag<ref>{{cite web |url= http://english.dipublico.com.ar/treaties/brussels-convention-on-the-liability-of-operators-of-nuclear-ships/ |title=Brussels Convention on the Liability of Operators of Nuclear Ships |work=International Law |publisher=Public International Law |access-date=March 17, 2011}}</ref> but was never ratified owing to disagreement on the inclusion of warships under the convention.<ref>{{cite web|url=http://ola.iaea.org/OLA/documents/liability%20regime.pdf |title=? |publisher=International Atomic Energy Association |access-date=March 17, 2011 |url-status=dead |archive-url=https://web.archive.org/web/20101217222929/http://ola.iaea.org/OLA/documents/liability%20regime.pdf |archive-date=December 17, 2010 }}</ref> Nuclear reactors under United States jurisdiction are insured by the provisions of the [[Price–Anderson_Nuclear_Industries_Indemnity_Act|Price–Anderson Act]].{{citation_needed|date=August 2019}} |
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==Military nuclear ships== |
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*they have a high power density in a small volume and therefore run on highly-enriched uranium (>20% U-235, originally c93% but apparently now c20-25% in western vessels, twice this in Russian ones), |
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[[File:USS Nimitz (CVN-68) with California (CGN-36) and South Carolina (CGN-37) c1976.jpg|thumb|In addition to nuclear-powered aircraft carriers, the United States once operated nuclear-powered cruisers.]] |
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*the fuel is not UO<sub>2</sub> but a metal-[[zirconium]] alloy (c15%U with 93% enrichment, or more U with lower enrichment), |
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By 1990, there were more nuclear reactors powering ships (mostly military) than there were generating electric power in commercial power plants worldwide.<ref>{{cite journal |title=Nuclear Weapons at Sea |journal=[[Bulletin of the Atomic Scientists]] |date=September 1990 |pages=48–49}}</ref> |
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*they have long core lives, so that refueling is needed only after 10 or more years, and new cores are designed to last 50 years in carriers and 30-40 years in submarines, |
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*the design enables a compact pressure vessel while maintaining safety. |
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The long core life is enabled by the relatively high enrichment of the uranium and by incorporating a "burnable poison" in the cores which is progressively depleted as [[fission product]]s and [[actinide]]s accumulate, leading to reduced [[fuel efficiency]]. The two effects cancel one another out. |
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Under the direction of [[U.S. Navy]] Captain (later Admiral) [[Hyman G. Rickover]],<ref>{{Cite book |isbn=978-0-306-80189-1 |page=388 |last1= Groves |first1= Leslie R. |last2=Teller |first2= Edward |title=Now it can be told |year=1983}}</ref> the design, development and production of nuclear marine propulsion plants started in the [[United States]] in the 1940s. The first prototype naval reactor was constructed and tested at the [[Naval Reactor Facility]] at the National Reactor Testing Station in Idaho (now called the [[Idaho National Laboratory]]) in 1953. |
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Long-term integrity of the compact reactor pressure vessel is maintained by providing an internal neutron shield. (This is in contrast to early Soviet civil PWR designs where embrittlement occurs due to neutron bombardment of a very narrow pressure vessel.) |
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=== Submarines === |
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Reactor sizes range up to [[1 E8 W|190]] [[MWt]] in the larger submarines and surface ships. The French [[Rubis class submarine|''Rubis''-class submarines]] have a [[1 E7 W|48 MW]] reactor which needs no refueling for 30 years. |
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{{Further|Nuclear submarine}} |
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[[File:FS Saphir 06.jpg|thumb|The nuclear-propelled {{ship|French submarine|Saphir|S602|6}} returning to [[Toulon]], its [[home port]], after [[Mission Héraclès]]]] |
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The first [[nuclear submarine]], {{USS|Nautilus|SSN-571}}, put to sea in 1955 (SS was a traditional [[hull classification symbol]] for U.S. submarines, while SSN denoted the first "nuclear" submarine).<ref>{{Cite book |isbn=978-0-16-059185-3 |last=Stacy |first=Susan |title=Proving the Principle: A History of the Idaho National Engineering and Environmental Laboratory, 1949–1999 |year=2000}}</ref> |
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The Soviet Union also developed nuclear submarines. The first types developed were the Project 627, NATO-designated {{sclass2|November|submarine|4}} with two water-cooled reactors, the first of which, K-3 ''Leninsky Komsomol'', was underway under nuclear power in 1958.<ref>{{Cite web|url=https://www.enseccoe.org/data/public/uploads/2020/11/02.-solo-article-lukas-smr-eh-15-web-version-final.pdf|title=Is Small Really Beautiful?The Future Role of Small Modular Nuclear Reactors (SMRs) In The Military|last=Trakimavičius|first=Lukas|website=NATO Energy Security Centre of Excellence|language=en|access-date=2020-12-05}}</ref> |
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The Russian, US and British navies rely on steam turbine propulsion, the French and Chinese use the turbine to generate electricity for propulsion. Most Russian submarines as well as all surface ships since ''Enterprise'' are powered by two reactors. US, British, French and Chinese submarines are powered by one. |
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Nuclear power revolutionized the submarine, finally making it a true "underwater" vessel, rather than a "submersible" craft, which could only stay underwater for limited periods. It gave the submarine the ability to operate submerged at high speeds, comparable to those of surface vessels, for unlimited periods, dependent only on the endurance of its crew. To demonstrate this {{USS|Triton|SSRN-586|6}} was the first vessel to execute a submerged [[circumnavigation]] of the Earth ([[Operation Sandblast]]), doing so in 1960.<ref>{{Cite web|title=First submarine circumnavigation|url=https://www.guinnessworldrecords.com/world-records/472299-first-submarine-circumnavigation/|website=Guinness World Records|language=en-GB|access-date=2020-06-02}}</ref> |
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Decommissioning nuclear-powered submarines has become a major task for US and Russian navies. After defuelling, US practice is to cut the reactor section from the vessel for disposal in shallow land burial as low-level waste (see the [[Ship-Submarine recycling program]]). In Russia the whole vessels, or the sealed reactor sections, remain stored afloat indefinitely. |
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''Nautilus'', with a [[pressurized water reactor]] (PWR), led to the parallel development of other submarines like a unique liquid metal cooled (sodium) reactor in {{USS|Seawolf|SSN-575|6}}, or two reactors in ''Triton'', and then the {{sclass|Skate|submarine|2}}s, powered by single reactors, and a cruiser, {{USS|Long Beach|CGN-9|6}}, in 1961, powered by two reactors.{{citation_needed|date=August 2019}} |
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A marine reactor was used to supply power ([[1 E6 W|1.5]] [[MWe]]) to a US [[Antarctic]] base for ten years to [[1972]], testing the feasibility of such air-portable units for remote locations. Russia is well advanced with plans to build a floating power plant for their far eastern territories. The design has two 35 MWe units based on the KLT-40 reactor used in icebreakers (with refueling every 4 years). Some Russian naval vessels have been used to supply electricity for domestic and industrial use in remote far eastern and Siberian towns. |
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By 1962, the [[United States Navy]] had 26 operational nuclear submarines and another 30 under construction. Nuclear power had revolutionized the Navy. The United States shared its technology with the [[United Kingdom]], while [[France|French]], [[Soviet Union|Soviet]], [[India]]n and [[China|Chinese]] development proceeded separately.{{citation_needed|date=August 2019}} |
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[[Harold Wilson]] the then British [[Prime Minister]] considered, but did not deploy, nuclear submarines to power [[Belfast]] during the [[1974]] Ulster Workers' Council Strike. |
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After the ''Skate''-class vessels, U.S. submarines were powered by a series of standardized, single-reactor designs built by [[Westinghouse Electric Corporation|Westinghouse]] and [[General Electric]]. [[Rolls-Royce plc]] built similar units for [[Royal Navy]] submarines, eventually developing a modified version of their own, the [[Rolls-Royce_PWR#PWR2|PWR2]].{{citation_needed|date=August 2019}} |
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''See also'': [[United States Naval reactor]] |
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The largest nuclear submarines ever built are the 26,500 tonne Russian {{sclass2|Typhoon|submarine|4}}. The smallest nuclear warships to date are the 2,700 tonne French {{sclass|Rubis|submarine|0}} attack submarines. The U.S. Navy operated an unarmed nuclear submarine, the [[NR-1 Deep Submergence Craft]], between 1969 and 2008, which was not a combat vessel but was the smallest nuclear-powered submarine at 400 tons.{{citation_needed|date=August 2019}} |
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=== Aircraft carriers === |
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The United States and France have built nuclear [[aircraft carrier]]s. |
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==== French Navy ==== |
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[[File:Charles De Gaulle (R91) underway 2009.jpg|thumb|right|The aircraft carrier {{ship|French aircraft carrier|Charles de Gaulle|R91|2}} of the [[French Navy]]]] |
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The sole French nuclear [[aircraft carrier]] example is {{ship|French aircraft carrier|Charles de Gaulle||2}}, commissioned in 2001 (a successor is planned).<ref>{{Cite web |date=23 October 2018 |title=Le programme du porte-avions qui remplacera le Charles-de-Gaulle est lancé |url= https://www.huffingtonpost.fr/2018/10/23/le-programme-du-porte-avions-qui-remplacera-le-charles-de-gaulle-est-lance_a_23569015/}}</ref> |
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The French carrier is [[CATOBAR| equipped with catapults and arresters]]. The {{ship|French aircraft carrier|Charles de Gaulle|R91|2}} has 42,000 tonnes, is the [[flagship]] of the French Navy (Marine Nationale). The ship carries a complement of [[Dassault Rafale|Dassault Rafale M]] and [[Grumman E-2 Hawkeye|E‑2C Hawkeye]] aircraft, [[Eurocopter EC725|EC725 Caracal]] and [[Eurocopter AS532 Cougar|AS532 Cougar]] helicopters for [[combat search and rescue]], as well as modern electronics and [[MBDA Aster |Aster]] missiles.<ref>{{cite web |url= http://www.globalsecurity.org/military/world/europe/cdg.htm |title=Charles de Gaulle |first= John |last=Pike |work= Global security |access-date=15 November 2015 |archive-url= https://web.archive.org/web/20151110034128/http://www.globalsecurity.org/military/world/europe/cdg.htm |archive-date=10 November 2015 |url-status=live |df=dmy-all }}</ref> |
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==== United States Navy ==== |
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The United States Navy operates 11 carriers, all nuclear-powered:<ref>{{Cite web|title=Naval Vessel Register|url=https://www.nvr.navy.mil/NVRSHIPS/ACTIVEINCOMMISSION.HTML|access-date=2020-06-01}}</ref> |
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*{{USS|Enterprise|CVN-65|6}}: in service 1962–2012, powered by eight reactor units, is still the only aircraft carrier to house more than two nuclear reactors, with each [[A2W reactor]] taking the place of one of the conventional boilers in earlier constructions.<ref>{{cite web |date=29 April 1999 |title=Speed Thrills III — Max speed of nuclear-powered aircraft carriers |url=http://www.navweaps.com/index_tech/tech-028.htm |access-date=20 April 2013 |publisher=Navweaps.com}}</ref> |
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*{{sclass|Nimitz|aircraft carrier|4}}: ten 101,000-ton, 1,092 ft long fleet carriers, the first of which was commissioned in 1975. A ''Nimitz''-class carrier is powered by two [[nuclear reactor]]s providing steam to four [[steam turbine]]s. |
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*{{sclass|Gerald R. Ford|aircraft carrier|4}}, one 110,000-ton, 1,106 ft long fleet carrier. The lead of the class {{USS|Gerald R. Ford|CVN-78|2}}, came into service in 2017, with another nine planned. |
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=== Destroyers and cruisers === |
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==== Russian Navy ==== |
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[[File:Tactical exercises of the Russian Navy.jpg|thumb|right|The Russian flagship ''Pyotr Veliky'']] |
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{{see also|Kirov-class battlecruiser}} |
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The ''Kirov'' class, Soviet designation 'Project 1144 Orlan' ([[sea eagle]]), is a class of [[nuclear powered|nuclear-powered]] [[guided missile cruiser|guided-missile cruiser]]s of the [[Soviet Navy]] and [[Russian Navy]], the largest and heaviest [[surface combatant]] warships (i.e. not an [[aircraft carrier]] or [[amphibious assault ship]]) in operation in the world. Among modern warships, they are second in size only to large [[aircraft carriers]], and of similar size to [[World War II]] era [[battleship]]s. The Soviet classification of the ship-type is "heavy nuclear-powered guided missile cruiser" ({{langx|ru|тяжёлый атомный ракетный крейсер}}). The ships are often referred to as [[battlecruiser]]s by Western defence commentators due to their size and general appearance.<ref>''Armi da guerra'', De Agostini, Novara, 1985.</ref> |
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==== United States Navy ==== |
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{{see also|Nuclear powered cruisers of the United States Navy}} |
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The [[United States Navy]] at one time had [[nuclear powered|nuclear-powered]] [[cruisers]] as part of its fleet. The first such ship was [[USS Long Beach (CGN-9)|USS ''Long Beach'' (CGN-9)]]. Commissioned in 1961, she was the world's first nuclear-powered [[surface combatant]].<ref>{{cite web|url=http://navysite.de/cg/cgn9.htm|title=USS Long Beach (CGN 9)}}</ref> She was followed a year later by [[USS Bainbridge (CGN-25)|USS ''Bainbridge'' (DLGN-25)]]. While ''Long Beach'' was designed and built as a cruiser,<ref>{{cite web|url=http://www.globalsecurity.org/military/systems/ship/cgn-9.htm|title=CGN-9 Long Beach|author=John Pike}}</ref> ''Bainbridge'' began life as a [[frigate]], though at that time the Navy was using the [[hull code]] "DLGN" for "[[destroyer leader]], [[guided missile]], [[nuclear power|nuclear]]".<ref>{{cite web | work = Global security |url = http://www.globalsecurity.org/military/systems/ship/cgn-25.htm |title=CGN 25 Bainbridge class|author=John Pike}}</ref> |
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The last nuclear-powered cruisers the Americans would produce would be the four-ship {{sclass|Virginia|cruiser|4}}. {{USS|Virginia|CGN-38}} was commissioned in 1976, followed by {{USS|Texas|CGN-39}} in 1977, {{USS|Mississippi|CGN-40}} in 1978 and finally {{USS|Arkansas|CGN-41}} in 1980. Ultimately, all these ships proved to be too costly to maintain<ref>{{cite web | work = Defense media network |url = http://www.defensemedianetwork.com/stories/nuclear-power-for-surface-combatants/2/|title=Nuclear power for surface combatants}}</ref> and they were all retired between 1993 and 1999.{{citation_needed|date=August 2019}} |
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=== Other military ships === |
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=== Communication and command ships === |
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[[File:Soviet command ship SSV-33.jpg|thumb|Command and communications ship SSV-33 ''Ural'']] |
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{{see also|Soviet communications ship SSV-33}} |
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'''''SSV-33 Ural''''' (''ССВ-33 Урал''; [[NATO reporting name]]: ''Kapusta'' <nowiki>[</nowiki>[[Russian language|Russian]] for "[[cabbage]]"]) was a [[command and control]] [[naval ship]] operated by the [[Soviet Navy]]. ''SSV-33''{{'}}s hull was derived from that of the [[nuclear power|nuclear-power]]ed {{sclass|Kirov|battlecruiser|1}}s with nuclear marine propulsion.<ref name="gs_kapusta">{{cite web |url=http://www.globalsecurity.org/military/world/russia/ssv-33.htm |title=SSV-33 Project 1941 |last=Pike |first=J. |website=GlobalSecurity.org |access-date=30 October 2015}}</ref> ''SSV-33'' served in [[ELINT|electronic intelligence]], missile tracking, space tracking, and communications relay roles. Due to high operating costs, ''SSV-33'' was laid up.<ref name="gs_kapusta" /> |
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''SSV-33'' carried only light defensive weapons. These were two AK-176 76 mm guns, four AK-630 30 mm guns, and four quadruple Igla missile mounts.{{citation_needed|date=August 2019}} |
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=== Nuclear-powered UUV === |
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{{see also|Status-6 Oceanic Multipurpose System}} |
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The '''Poseidon''' ({{langx|ru|Посейдон}}, "[[Poseidon]]", [[NATO reporting name]] '''Kanyon'''), previously known by Russian codename '''Status-6''' ({{langx|ru|Статус-6}}), is a nuclear-powered and nuclear-armed [[unmanned underwater vehicle]] under development by [[Rubin Design Bureau]], capable of delivering both conventional and nuclear [[payloads]]. According to Russian state TV, it is able to deliver a [[thermonuclear]] [[cobalt bomb]] of up to 200 [[megatonne]]s (four times as powerful as the most powerful device ever detonated, the [[Tsar Bomba]], and twice its maximum theoretical yield) against an enemy's naval ports and coastal cities.<ref name="urlRussian media: nuclear torpedo can destroy the US, Europe, the world - Business Insider">{{cite web |url= https://www.businessinsider.com/russian-media-nuclear-torpedo-can-destroy-the-us-europe-the-world-2019-1?IR=T |title=Russian media: nuclear torpedo can destroy the US, Europe, the world |website= [[Business Insider]] }}</ref> |
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==Civilian nuclear ships== |
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[[File:Ns-savanna-eng.jpg|thumb|140px|Engineer epaulette from ''Savannah'']] |
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The following are [[ship]]s that are or were in commercial or civilian use and have nuclear marine propulsion. |
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===Merchant ships=== |
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Nuclear-powered civil merchant ships have not developed beyond a few experimental ships. The U.S.-built {{ship|NS|Savannah}}, completed in 1962, was primarily a demonstration of civil nuclear power and was too small and expensive to operate economically as a merchant ship. The design was too much of a compromise, being neither an efficient freighter nor a viable passenger liner. The German-built {{ship||Otto Hahn|ship|2}}, completed in 1968, a cargo ship and research facility, sailed some {{convert|650000|nmi|km}} on 126 voyages over 10 years without any technical problems.{{Citation needed|date=February 2007}} It proved too expensive to operate and was converted to diesel. The Japanese {{ship||Mutsu|nuclear ship|2}}, completed in 1972, was dogged by technical and political problems. Its reactor had significant radiation leakage and fishermen protested against the vessel's operation. All of these three ships used low-enriched uranium. ''[[Sevmorput]]'', a Soviet and later Russian [[Lighter aboard ship|LASH carrier]] with icebreaking capability, has operated successfully on the [[Northern Sea Route]] since it was commissioned in 1988. {{Asof|2021}}, it is the only nuclear-powered merchant ship in service.{{citation_needed|date=August 2019}} |
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Civilian nuclear ships suffer from the costs of specialized infrastructure. The ''Savannah'' was expensive to operate since it was the only vessel using its specialized nuclear shore staff and servicing facility. A larger fleet could share fixed costs among more operating vessels, reducing operating costs. |
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Despite this, there is still interest in nuclear propulsion. In November 2010 British Maritime Technology and Lloyd's Register embarked upon a two-year study with U.S.-based Hyperion Power Generation (now [[Gen4 Energy]]), and the Greek ship operator Enterprises Shipping and Trading SA to investigate the practical maritime applications for small modular reactors. The research intended to produce a concept tanker-ship design, based on a 70 MWt reactor such as Hyperion's. In response to its members' interest in nuclear propulsion, Lloyd's Register has also re-written its 'rules' for nuclear ships, which concern the integration of a reactor certified by a land-based regulator with the rest of the ship. The overall rationale of the rule-making process assumes that in contrast to the current marine industry practice where the designer/builder typically demonstrates compliance with regulatory requirements, in the future the nuclear regulators will wish to ensure that it is the operator of the nuclear plant that demonstrates safety in operation, in addition to the safety through design and construction. Nuclear ships are currently the responsibility of their own countries, but none are involved in international trade. As a result of this work in 2014 two papers on commercial nuclear marine propulsion were published by Lloyd's Register and the other members of this consortium.<ref name="Hirdaris 101–130"/><ref name="Hirdaris A37-A60"/> These publications review past and recent work in the area of marine nuclear propulsion and describe a preliminary concept design study for a {{DWT|155,000}} Suezmax tanker that is based on a conventional hull form with alternative arrangements for accommodating a 70 MWt nuclear propulsion plant delivering up to 23.5 MW shaft power at maximum continuous rating (average: 9.75 MW). The Gen4Energy power module is considered. This is a small fast-neutron reactor using lead–bismuth eutectic cooling and able to operate for ten full-power years before refueling, and in service last for a 25-year operational life of the vessel. They conclude that the concept is feasible, but further maturity of nuclear technology and the development and harmonisation of the regulatory framework would be necessary before the concept would be viable.{{citation_needed|date=August 2019}} |
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Nuclear propulsion has been proposed again on the wave of [[low-carbon economy|decarbonization]] of marine shipping, which accounts for 3–4% of global greenhouse gas emissions.<ref>{{Cite web|date=2020-11-04|title=Shipping industry should consider nuclear option for decarbonizing: experts {{!}} S&P Global Platts|url=https://www.spglobal.com/platts/en/market-insights/latest-news/shipping/110420-shipping-industry-should-consider-nuclear-option-for-decarbonizing-experts|access-date=2020-11-06|website=www.spglobal.com|language=en}}</ref> |
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===Merchant cargo ships=== |
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* [[USNS American Explorer|USNS ''American Explorer'']]; United States tanker, converted to conventional power while under construction |
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* {{ship||Mutsu|nuclear ship|2}}, Japan (1970–1992); never carried commercial cargo, rebuilt as diesel engine powered ''RV Mirai'' in 1996 |
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* {{ship||Otto Hahn|ship|2}}, Germany (1968–1979); re-powered with diesel engine in 1979 |
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* {{ship|NS|Savannah}}, United States (1962–1972) |
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* ''[[Sevmorput]]'', Russia (1988–present), ice-strengthened nuclear-powered [[lighter aboard ship]] (LASH) carrier |
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In December 5, 2023, the [[Jiangnan Shipyard]] under the [[China State Shipbuilding Corporation]] officially released a design of a 24000 [[twenty-foot equivalent unit|TEU]]-class [[container ship]] — known as the KUN-24AP — at Marintec China 2023, a premier maritime industry exhibition held in [[Shanghai]]. The container ship is reported to be powered by a [[thorium-based nuclear power|thorium-based]] [[molten salt reactor]], making it a first thorium-powered container ship and, if completed, the largest nuclear-powered container ship in the world.<ref>{{cite web|url=https://www.scmp.com/news/china/science/article/3243966/chinese-shipyard-unveils-plans-worlds-first-nuclear-tanker-powered-cutting-edge-molten-salt-reactor|title=Chinese shipyard unveils plans for world's first nuclear container powered by cutting-edge molten salt reactor|date=2023-12-05|last=Chen|first=Stephen|publisher=[[South China Morning Post]]|accessdate=2023-12-07}}</ref> |
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===Icebreakers=== |
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{{main|Nuclear-powered icebreaker}} |
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Nuclear propulsion has proven both technically and economically feasible for [[nuclear-powered icebreaker]]s in the [[Soviet Union|Soviet]], and later [[Russia|Russian]], [[Arctic]]. Nuclear-fuelled ships operate for years without refueling, and the vessels have powerful engines, well-suited to the task of icebreaking.{{citation_needed|date=August 2019}} |
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The [[Lenin (nuclear icebreaker)|Soviet icebreaker ''Lenin'']] was the world's first nuclear-powered surface vessel in 1959 and remained in service for 30 years (new reactors were fitted in 1970). It led to a series of larger icebreakers, the 23,500 [[Tonnage|ton]] {{sclass|Arktika|icebreaker|4}} of six vessels, launched beginning in 1975. These vessels have two reactors and are used in deep Arctic waters. [[Arktika (1972 nuclear icebreaker)|NS ''Arktika'']] was the first surface vessel to reach the [[North Pole]].{{citation_needed|date=August 2019}} |
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For use in shallow waters such as estuaries and rivers, shallow-draft, [[Nuclear-powered icebreaker#Taymyr class|''Taymyr''-class icebreakers]] were built in [[Finland]] and then fitted with their single-reactor nuclear propulsion system in [[Russia]]. They were built to conform to international safety standards for nuclear vessels.<ref>{{cite book |editor-first=Cutler J |editor-last=Cleveland |title=Encyclopedia of Energy |volume=1–6 |publisher=Elsevier |year=2004 |isbn=978-0-12-176480-7 |pages=336–340}}</ref> |
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All nuclear-powered icebreakers have been commissioned by the Soviet Union or Russia.{{citation_needed|date=August 2019}} |
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* {{ship||Lenin|1957 icebreaker|2}} (1959–1989; museum ship) |
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* {{ship||Arktika|1972 icebreaker|2}} (1975–2008; decommissioned) |
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* {{ship||Sibir|1977 icebreaker|2}} (1977–1992; scrapped) |
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* {{ship||Rossiya|1983 icebreaker|2}} (1985–2013; decommissioned) |
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* {{ship||Taymyr|1987 icebreaker|2}} (1989–present) |
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* {{ship||Sovetskiy Soyuz|icebreaker|2}} (1989–2014; decommissioned) |
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* {{ship||Vaygach|1989 icebreaker|2}} (1990–present) |
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* {{ship||Yamal|icebreaker|2}} (1992–present) |
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* {{ship||50 Let Pobedy}}, formerly ''Ural'' (2007–present) |
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* {{ship||Arktika|2016 icebreaker|2}} (2020–present)<ref>{{Cite web|date=2020-10-21|language=ru|title=На ледоколе 'Арктика' поднят российский флаг|url=http://sudostroenie.info/novosti/31504.html|access-date=2021-02-07|website=sudostroenie.info}}</ref> |
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* {{ship||Sibir|2017 icebreaker|2}} (2021–present) |
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* {{ship||Ural|icebreaker|2}} (2022–present)<ref>{{cite web|url=https://en.portnews.ru/news/339556/|title=Nuclear-powered icebreaker Ural of Project 22220 leaves Murmansk for the first operational voyage|publisher=PortNews|date=2 December 2022|accessdate=4 December 2022}}</ref> |
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==See also== |
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* [[Air-independent propulsion]] |
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* [[Aircraft Nuclear Propulsion]] |
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* [[Knolls Atomic Power Laboratory]] |
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* [[List of United States Naval reactors]] |
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* [[Naval Reactors]] |
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* [[Nuclear navy]] |
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* [[Nuclear-powered aircraft]] |
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* [[Nuclear Power School]] |
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* [[Soviet naval reactors]] |
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* [[United States naval reactors]] |
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* [[United States Navy Nuclear Propulsion]] |
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==Notes== |
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===Citations=== |
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{{reflist}} |
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==References== |
==References== |
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{{refbegin}} |
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* AFP, 11 November 1998; in "Nuclear Submarines Provide Electricity for Siberian Town," FBIS-SOV-98-315, 11 November 1998. |
* AFP, 11 November 1998; in "Nuclear Submarines Provide Electricity for Siberian Town," FBIS-SOV-98-315, 11 November 1998. |
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* ITAR-TASS, 11 November 1998; in "Russian Nuclear Subs Supply Electricity to Town in Far East," FBIS-SOV-98-316, 12 November 1998. |
* ITAR-TASS, 11 November 1998; in "Russian Nuclear Subs Supply Electricity to Town in Far East," FBIS-SOV-98-316, 12 November 1998. |
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* [http://news.bbc.co.uk/1/hi/northern_ireland/4132635.stm Harold Wilson's plan] BBC News story |
* [http://news.bbc.co.uk/1/hi/northern_ireland/4132635.stm Harold Wilson's plan] BBC News story |
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* {{cite book |editor-last1=Sarkisov |editor-first1=Ashot A. |editor-last2=Tournyol du Clos |editor-first2=Alain |date=1999 |title=Analysis of Risks Associated with Nuclear Submarine Decommissioning, Dismantling and Disposal |series= NATO Science Partnership Subseries 1: Disarmament Technologies |volume=24|location=Dordrecht |publisher=Springer |isbn=978-0-7923-5598-4}} |
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{{refend}} |
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==External links== |
==External links== |
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* [http://www.world-nuclear.org/ The World Nuclear Association] |
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*[http://www.uic.com.au/ The Uranium Information Centre] provided some of the original material in this article. |
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* [https://web.archive.org/web/20070726214243/https://nnptc.cnet.navy.mil/ Naval Nuclear Power Training Command] |
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{{Nuclear propulsion}} |
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{{Authority control}} |
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[[Category:Nuclear technology]] |
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[[Category:Marine propulsion]] |
[[Category:Marine propulsion]] |
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[[Category:Nuclear-powered ships| ]] |
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[[Category:Nuclear-powered ships of the United States Navy|*]] |
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[[Category:Nuclear technology-related lists|Marine propulsion]] |
Latest revision as of 21:45, 20 October 2024
Nuclear marine propulsion is propulsion of a ship or submarine with heat provided by a nuclear reactor. The power plant heats water to produce steam for a turbine used to turn the ship's propeller through a gearbox or through an electric generator and motor. Nuclear propulsion is used primarily within naval warships such as nuclear submarines and supercarriers. A small number of experimental civil nuclear ships have been built.[1]
Compared to oil- or coal-fuelled ships, nuclear propulsion offers the advantage of very long intervals of operation before refueling. All the fuel is contained within the nuclear reactor, so no cargo or supplies space is taken up by fuel, nor is space taken up by exhaust stacks or combustion air intakes.[2] The low fuel cost is offset by high operating costs and investment in infrastructure, however, so nearly all nuclear-powered vessels are military.[2]
Power plants
[edit]Basic operation of naval ship or submarine
[edit]Most naval nuclear reactors are of the pressurized water type, with the exception of a few[quantify] attempts[by whom?] at using liquid sodium-cooled reactors.[2] A primary water circuit transfers heat generated from nuclear fission in the fuel to a steam generator; this water is kept under pressure so it does not boil. This circuit operates at a temperature of around 250 to 300 °C (482 to 572 °F). Any radioactive contamination in the primary water is confined. Water is circulated by pumps; at lower power levels, reactors designed for submarines may rely on natural circulation of the water to reduce noise generated by the pumps.[citation needed]
The hot water from the reactor heats a separate water circuit in the steam generator. That water is converted to steam and passes through steam driers on its way to the steam turbine. Spent steam at low pressure runs through a condenser cooled by seawater and returns to liquid form. The water is pumped back to the steam generator and continues the cycle. Any water lost in the process can be made up by desalinated sea water added to the steam generator feed water.[3]
In the turbine, the steam expands and reduces its pressure as it imparts energy to the rotating blades of the turbine. There may be many stages of rotating blades and fixed guide vanes. The output shaft of the turbine may be connected to a gearbox to reduce rotation speed, then a shaft connects to the vessel's propellers. In another form of drive system, the turbine turns an electrical generator, and the electric power produced is fed to one or more drive motors for the vessel's propellers. The Russian, U.S. and British navies rely on direct steam turbine propulsion, while French and Chinese ships use the turbine to generate electricity for propulsion (turbo-electric transmission).[citation needed]
Some nuclear submarines have a single reactor, but Russian submarines have two, and so had USS Triton. Most American aircraft carriers are powered by two reactors, but USS Enterprise had eight. The majority of marine reactors are of the pressurized water type, although the U.S. and Soviet navies have designed warships powered with liquid metal cooled reactors.[citation needed]
Differences from land power plants
[edit]Marine-type reactors differ from land-based commercial electric power reactors in several respects.[citation needed]
While land-based reactors in nuclear power plants produce up to around 1600 megawatts of net electrical power (the nameplate capacity of the EPR), a typical marine propulsion reactor produces no more than a few hundred megawatts. Some small modular reactors (SMR) are similar to marine propulsion reactors in capacity and some design considerations and thus nuclear marine propulsion (whether civilian or military) is sometimes proposed as an additional market niche for SMRs. Unlike for land-based applications where hundreds of hectares can be occupied by installations like Bruce Nuclear Generating Station, at sea tight space limits dictate that a marine reactor must be physically small, so it must generate higher power per unit of space. This means its components are subject to greater stresses than those of a land-based reactor. Its mechanical systems must operate flawlessly under the adverse conditions encountered at sea, including vibration and the pitching and rolling of a ship operating in rough seas. Reactor shutdown mechanisms cannot rely on gravity to drop control rods into place as in a land-based reactor that always remains upright. Salt water corrosion is an additional problem that complicates maintenance.[citation needed]
As the core of a seagoing reactor is much smaller than a power reactor, the probability of a neutron intersecting with a fissionable nucleus before it escapes into the shielding is much lower. As such, the fuel is typically more highly enriched (i.e., contains a higher concentration of 235U vs. 238U) than that used in a land-based nuclear power plant, which increases the probability of fission to the level where a sustained reaction can occur. Some marine reactors run on relatively low-enriched uranium, which requires more frequent refueling. Others run on highly enriched uranium, varying from 20% 235U, to the over 96% 235U found in U.S. submarines,[4] in which the resulting smaller core is quieter in operation (a big advantage to a submarine).[5] Using more-highly enriched fuel also increases the reactor's power density and extends the usable life of the nuclear fuel load, but is more expensive and a greater risk to nuclear proliferation than less-highly enriched fuel.[6]
A marine nuclear propulsion plant must be designed to be highly reliable and self-sufficient, requiring minimal maintenance and repairs, which might have to be undertaken many thousands of miles from its home port. One of the technical difficulties in designing fuel elements for a seagoing nuclear reactor is the creation of fuel elements that will withstand a large amount of radiation damage. Fuel elements may crack over time and gas bubbles may form. The fuel used in marine reactors is a metal-zirconium alloy rather than the ceramic UO2 (uranium dioxide) often used in land-based reactors. Marine reactors are designed for long core life, enabled by the relatively high enrichment of the uranium and by incorporating a "burnable poison" in the fuel elements, which is slowly depleted as the fuel elements age and become less reactive. The gradual dissipation of the "nuclear poison" increases the reactivity of the core to compensate for the lessening reactivity of the aging fuel elements, thereby extending the usable life of the fuel. The compact reactor pressure vessel is provided with an internal neutron shield, which reduces the damage to the steel from constant neutron bombardment.[citation needed]
Decommissioning
[edit]Decommissioning nuclear-powered submarines has become a major task for U.S. and Russian navies.[7] After defuelling, U.S. practice is to cut the reactor section from the vessel for disposal in shallow land burial as low-level waste (see the ship-submarine recycling program).[8] In Russia, whole vessels, or sealed reactor sections, typically remain stored afloat, although a new facility near Sayda Bay is to provide storage in a concrete-floored facility on land for some submarines in the far north.[citation needed]
Future designs
[edit]Russia built a floating nuclear power plant for its far eastern territories. The design has two 35 MWe units based on the KLT-40 reactor used in icebreakers (with refueling every four years). Some Russian naval vessels have been used to supply electricity for domestic and industrial use in remote far eastern and Siberian towns.[citation needed]
In 2010, Lloyd's Register was investigating the possibility of civilian nuclear marine propulsion and rewriting draft rules (see text under Merchant Ships).[9][10][11]
Civil liability
[edit]Insurance of nuclear vessels is not like the insurance of conventional ships. The consequences of an accident could span national boundaries, and the magnitude of possible damage is beyond the capacity of private insurers.[12] A special international agreement, the Brussels Convention on the Liability of Operators of Nuclear Ships, developed in 1962, would have made signatory national governments liable for accidents caused by nuclear vessels under their flag[13] but was never ratified owing to disagreement on the inclusion of warships under the convention.[14] Nuclear reactors under United States jurisdiction are insured by the provisions of the Price–Anderson Act.[citation needed]
Military nuclear ships
[edit]By 1990, there were more nuclear reactors powering ships (mostly military) than there were generating electric power in commercial power plants worldwide.[15]
Under the direction of U.S. Navy Captain (later Admiral) Hyman G. Rickover,[16] the design, development and production of nuclear marine propulsion plants started in the United States in the 1940s. The first prototype naval reactor was constructed and tested at the Naval Reactor Facility at the National Reactor Testing Station in Idaho (now called the Idaho National Laboratory) in 1953.
Submarines
[edit]The first nuclear submarine, USS Nautilus (SSN-571), put to sea in 1955 (SS was a traditional hull classification symbol for U.S. submarines, while SSN denoted the first "nuclear" submarine).[17]
The Soviet Union also developed nuclear submarines. The first types developed were the Project 627, NATO-designated November class with two water-cooled reactors, the first of which, K-3 Leninsky Komsomol, was underway under nuclear power in 1958.[18]
Nuclear power revolutionized the submarine, finally making it a true "underwater" vessel, rather than a "submersible" craft, which could only stay underwater for limited periods. It gave the submarine the ability to operate submerged at high speeds, comparable to those of surface vessels, for unlimited periods, dependent only on the endurance of its crew. To demonstrate this USS Triton was the first vessel to execute a submerged circumnavigation of the Earth (Operation Sandblast), doing so in 1960.[19]
Nautilus, with a pressurized water reactor (PWR), led to the parallel development of other submarines like a unique liquid metal cooled (sodium) reactor in USS Seawolf, or two reactors in Triton, and then the Skate-class submarines, powered by single reactors, and a cruiser, USS Long Beach, in 1961, powered by two reactors.[citation needed]
By 1962, the United States Navy had 26 operational nuclear submarines and another 30 under construction. Nuclear power had revolutionized the Navy. The United States shared its technology with the United Kingdom, while French, Soviet, Indian and Chinese development proceeded separately.[citation needed]
After the Skate-class vessels, U.S. submarines were powered by a series of standardized, single-reactor designs built by Westinghouse and General Electric. Rolls-Royce plc built similar units for Royal Navy submarines, eventually developing a modified version of their own, the PWR2.[citation needed]
The largest nuclear submarines ever built are the 26,500 tonne Russian Typhoon class. The smallest nuclear warships to date are the 2,700 tonne French Rubis-class attack submarines. The U.S. Navy operated an unarmed nuclear submarine, the NR-1 Deep Submergence Craft, between 1969 and 2008, which was not a combat vessel but was the smallest nuclear-powered submarine at 400 tons.[citation needed]
Aircraft carriers
[edit]The United States and France have built nuclear aircraft carriers.
French Navy
[edit]The sole French nuclear aircraft carrier example is Charles de Gaulle, commissioned in 2001 (a successor is planned).[20]
The French carrier is equipped with catapults and arresters. The Charles de Gaulle has 42,000 tonnes, is the flagship of the French Navy (Marine Nationale). The ship carries a complement of Dassault Rafale M and E‑2C Hawkeye aircraft, EC725 Caracal and AS532 Cougar helicopters for combat search and rescue, as well as modern electronics and Aster missiles.[21]
United States Navy
[edit]The United States Navy operates 11 carriers, all nuclear-powered:[22]
- USS Enterprise: in service 1962–2012, powered by eight reactor units, is still the only aircraft carrier to house more than two nuclear reactors, with each A2W reactor taking the place of one of the conventional boilers in earlier constructions.[23]
- Nimitz class: ten 101,000-ton, 1,092 ft long fleet carriers, the first of which was commissioned in 1975. A Nimitz-class carrier is powered by two nuclear reactors providing steam to four steam turbines.
- Gerald R. Ford class, one 110,000-ton, 1,106 ft long fleet carrier. The lead of the class Gerald R. Ford, came into service in 2017, with another nine planned.
Destroyers and cruisers
[edit]Russian Navy
[edit]The Kirov class, Soviet designation 'Project 1144 Orlan' (sea eagle), is a class of nuclear-powered guided-missile cruisers of the Soviet Navy and Russian Navy, the largest and heaviest surface combatant warships (i.e. not an aircraft carrier or amphibious assault ship) in operation in the world. Among modern warships, they are second in size only to large aircraft carriers, and of similar size to World War II era battleships. The Soviet classification of the ship-type is "heavy nuclear-powered guided missile cruiser" (Russian: тяжёлый атомный ракетный крейсер). The ships are often referred to as battlecruisers by Western defence commentators due to their size and general appearance.[24]
United States Navy
[edit]The United States Navy at one time had nuclear-powered cruisers as part of its fleet. The first such ship was USS Long Beach (CGN-9). Commissioned in 1961, she was the world's first nuclear-powered surface combatant.[25] She was followed a year later by USS Bainbridge (DLGN-25). While Long Beach was designed and built as a cruiser,[26] Bainbridge began life as a frigate, though at that time the Navy was using the hull code "DLGN" for "destroyer leader, guided missile, nuclear".[27]
The last nuclear-powered cruisers the Americans would produce would be the four-ship Virginia class. USS Virginia (CGN-38) was commissioned in 1976, followed by USS Texas (CGN-39) in 1977, USS Mississippi (CGN-40) in 1978 and finally USS Arkansas (CGN-41) in 1980. Ultimately, all these ships proved to be too costly to maintain[28] and they were all retired between 1993 and 1999.[citation needed]
Other military ships
[edit]Communication and command ships
[edit]SSV-33 Ural (ССВ-33 Урал; NATO reporting name: Kapusta [Russian for "cabbage"]) was a command and control naval ship operated by the Soviet Navy. SSV-33's hull was derived from that of the nuclear-powered Kirov-class battlecruisers with nuclear marine propulsion.[29] SSV-33 served in electronic intelligence, missile tracking, space tracking, and communications relay roles. Due to high operating costs, SSV-33 was laid up.[29]
SSV-33 carried only light defensive weapons. These were two AK-176 76 mm guns, four AK-630 30 mm guns, and four quadruple Igla missile mounts.[citation needed]
Nuclear-powered UUV
[edit]The Poseidon (Russian: Посейдон, "Poseidon", NATO reporting name Kanyon), previously known by Russian codename Status-6 (Russian: Статус-6), is a nuclear-powered and nuclear-armed unmanned underwater vehicle under development by Rubin Design Bureau, capable of delivering both conventional and nuclear payloads. According to Russian state TV, it is able to deliver a thermonuclear cobalt bomb of up to 200 megatonnes (four times as powerful as the most powerful device ever detonated, the Tsar Bomba, and twice its maximum theoretical yield) against an enemy's naval ports and coastal cities.[30]
Civilian nuclear ships
[edit]The following are ships that are or were in commercial or civilian use and have nuclear marine propulsion.
Merchant ships
[edit]Nuclear-powered civil merchant ships have not developed beyond a few experimental ships. The U.S.-built NS Savannah, completed in 1962, was primarily a demonstration of civil nuclear power and was too small and expensive to operate economically as a merchant ship. The design was too much of a compromise, being neither an efficient freighter nor a viable passenger liner. The German-built Otto Hahn, completed in 1968, a cargo ship and research facility, sailed some 650,000 nautical miles (1,200,000 km) on 126 voyages over 10 years without any technical problems.[citation needed] It proved too expensive to operate and was converted to diesel. The Japanese Mutsu, completed in 1972, was dogged by technical and political problems. Its reactor had significant radiation leakage and fishermen protested against the vessel's operation. All of these three ships used low-enriched uranium. Sevmorput, a Soviet and later Russian LASH carrier with icebreaking capability, has operated successfully on the Northern Sea Route since it was commissioned in 1988. As of 2021[update], it is the only nuclear-powered merchant ship in service.[citation needed]
Civilian nuclear ships suffer from the costs of specialized infrastructure. The Savannah was expensive to operate since it was the only vessel using its specialized nuclear shore staff and servicing facility. A larger fleet could share fixed costs among more operating vessels, reducing operating costs.
Despite this, there is still interest in nuclear propulsion. In November 2010 British Maritime Technology and Lloyd's Register embarked upon a two-year study with U.S.-based Hyperion Power Generation (now Gen4 Energy), and the Greek ship operator Enterprises Shipping and Trading SA to investigate the practical maritime applications for small modular reactors. The research intended to produce a concept tanker-ship design, based on a 70 MWt reactor such as Hyperion's. In response to its members' interest in nuclear propulsion, Lloyd's Register has also re-written its 'rules' for nuclear ships, which concern the integration of a reactor certified by a land-based regulator with the rest of the ship. The overall rationale of the rule-making process assumes that in contrast to the current marine industry practice where the designer/builder typically demonstrates compliance with regulatory requirements, in the future the nuclear regulators will wish to ensure that it is the operator of the nuclear plant that demonstrates safety in operation, in addition to the safety through design and construction. Nuclear ships are currently the responsibility of their own countries, but none are involved in international trade. As a result of this work in 2014 two papers on commercial nuclear marine propulsion were published by Lloyd's Register and the other members of this consortium.[10][11] These publications review past and recent work in the area of marine nuclear propulsion and describe a preliminary concept design study for a 155,000 DWT Suezmax tanker that is based on a conventional hull form with alternative arrangements for accommodating a 70 MWt nuclear propulsion plant delivering up to 23.5 MW shaft power at maximum continuous rating (average: 9.75 MW). The Gen4Energy power module is considered. This is a small fast-neutron reactor using lead–bismuth eutectic cooling and able to operate for ten full-power years before refueling, and in service last for a 25-year operational life of the vessel. They conclude that the concept is feasible, but further maturity of nuclear technology and the development and harmonisation of the regulatory framework would be necessary before the concept would be viable.[citation needed]
Nuclear propulsion has been proposed again on the wave of decarbonization of marine shipping, which accounts for 3–4% of global greenhouse gas emissions.[31]
Merchant cargo ships
[edit]- USNS American Explorer; United States tanker, converted to conventional power while under construction
- Mutsu, Japan (1970–1992); never carried commercial cargo, rebuilt as diesel engine powered RV Mirai in 1996
- Otto Hahn, Germany (1968–1979); re-powered with diesel engine in 1979
- NS Savannah, United States (1962–1972)
- Sevmorput, Russia (1988–present), ice-strengthened nuclear-powered lighter aboard ship (LASH) carrier
In December 5, 2023, the Jiangnan Shipyard under the China State Shipbuilding Corporation officially released a design of a 24000 TEU-class container ship — known as the KUN-24AP — at Marintec China 2023, a premier maritime industry exhibition held in Shanghai. The container ship is reported to be powered by a thorium-based molten salt reactor, making it a first thorium-powered container ship and, if completed, the largest nuclear-powered container ship in the world.[32]
Icebreakers
[edit]Nuclear propulsion has proven both technically and economically feasible for nuclear-powered icebreakers in the Soviet, and later Russian, Arctic. Nuclear-fuelled ships operate for years without refueling, and the vessels have powerful engines, well-suited to the task of icebreaking.[citation needed]
The Soviet icebreaker Lenin was the world's first nuclear-powered surface vessel in 1959 and remained in service for 30 years (new reactors were fitted in 1970). It led to a series of larger icebreakers, the 23,500 ton Arktika class of six vessels, launched beginning in 1975. These vessels have two reactors and are used in deep Arctic waters. NS Arktika was the first surface vessel to reach the North Pole.[citation needed]
For use in shallow waters such as estuaries and rivers, shallow-draft, Taymyr-class icebreakers were built in Finland and then fitted with their single-reactor nuclear propulsion system in Russia. They were built to conform to international safety standards for nuclear vessels.[33]
All nuclear-powered icebreakers have been commissioned by the Soviet Union or Russia.[citation needed]
- Lenin (1959–1989; museum ship)
- Arktika (1975–2008; decommissioned)
- Sibir (1977–1992; scrapped)
- Rossiya (1985–2013; decommissioned)
- Taymyr (1989–present)
- Sovetskiy Soyuz (1989–2014; decommissioned)
- Vaygach (1990–present)
- Yamal (1992–present)
- 50 Let Pobedy, formerly Ural (2007–present)
- Arktika (2020–present)[34]
- Sibir (2021–present)
- Ural (2022–present)[35]
See also
[edit]- Air-independent propulsion
- Aircraft Nuclear Propulsion
- Knolls Atomic Power Laboratory
- List of United States Naval reactors
- Naval Reactors
- Nuclear navy
- Nuclear-powered aircraft
- Nuclear Power School
- Soviet naval reactors
- United States naval reactors
- United States Navy Nuclear Propulsion
Notes
[edit]Citations
[edit]- ^ Wirt, John G (1979). "A Federal Demonstration Project: N.S. Savannah". Innovation in the maritime industry. Vol. 1. National Academies, for Maritime Transportation Research Board, National Research Council (U.S.). pp. 29–36.
- ^ a b c Trakimavičius, Lukas. "The Future Role of Nuclear Propulsion in the Military" (PDF). NATO Energy Security Centre of Excellence. Retrieved 2021-10-15.
- ^ Viren Chopra, Rob Houston (ed), DK Eyewitness Books: Transportation, Penguin, 2012, ISBN 1465408894 page 60
- ^ Moltz, James Clay (March 2006). "Global Submarine Proliferation: Emerging Trends and Problems". NTI. Archived from the original on 2007-02-09. Retrieved 2007-03-07.
- ^ Acton, James (December 13, 2007). "Silence is highly enriched uranium". Retrieved 2007-12-13.
- ^ "Ending the Production of Highly Enriched Uranium for Naval Reactors" (PDF). James Martin Center for Nonproliferation Studies. Retrieved September 25, 2008.
- ^ Sarkisov and Tournyol du Clos (1999), p. 3.
- ^ Sarkisov and Tournyol du Clos (1999), p. 3-4.
- ^ "Full steam ahead for nuclear shipping", World Nuclear News, 18 November 2010, retrieved 27 November 2010.
- ^ a b Hirdaris, Spyros; Cheng, YF; Shallcross, P; Bonafoux, J; Carlson, D; Prince, B; Sarris, GA (15 March 2014). "Considerations on the potential use of Nuclear Small Modular Reactor (SMR) technology for merchant marine propulsion". Ocean Engineering. 79: 101–130. doi:10.1016/j.oceaneng.2013.10.015.
- ^ a b Hirdaris, Spyros; Cheng, YF; Shallcross, P; Bonafoux, J; Carlson, D; Prince, B; Sarris, GA (March 2014). "Concept Design for a Suezmax Tanker Powered by a 70 MW Small Modular Reactor". Transactions of the Royal Institution of Naval Architects Part A: International Journal of Maritime Engineering. 156 (A1): A37–A60. doi:10.3940/rina.ijme.2014.a1.276.
- ^ "Liability for Nuclear Damage". World Nuclear Association. Retrieved March 17, 2011.
- ^ "Brussels Convention on the Liability of Operators of Nuclear Ships". International Law. Public International Law. Retrieved March 17, 2011.
- ^ "?" (PDF). International Atomic Energy Association. Archived from the original (PDF) on December 17, 2010. Retrieved March 17, 2011.
- ^ "Nuclear Weapons at Sea". Bulletin of the Atomic Scientists: 48–49. September 1990.
- ^ Groves, Leslie R.; Teller, Edward (1983). Now it can be told. p. 388. ISBN 978-0-306-80189-1.
- ^ Stacy, Susan (2000). Proving the Principle: A History of the Idaho National Engineering and Environmental Laboratory, 1949–1999. ISBN 978-0-16-059185-3.
- ^ Trakimavičius, Lukas. "Is Small Really Beautiful?The Future Role of Small Modular Nuclear Reactors (SMRs) In The Military" (PDF). NATO Energy Security Centre of Excellence. Retrieved 2020-12-05.
- ^ "First submarine circumnavigation". Guinness World Records. Retrieved 2020-06-02.
- ^ "Le programme du porte-avions qui remplacera le Charles-de-Gaulle est lancé". 23 October 2018.
- ^ Pike, John. "Charles de Gaulle". Global security. Archived from the original on 10 November 2015. Retrieved 15 November 2015.
- ^ "Naval Vessel Register". Retrieved 2020-06-01.
- ^ "Speed Thrills III — Max speed of nuclear-powered aircraft carriers". Navweaps.com. 29 April 1999. Retrieved 20 April 2013.
- ^ Armi da guerra, De Agostini, Novara, 1985.
- ^ "USS Long Beach (CGN 9)".
- ^ John Pike. "CGN-9 Long Beach".
- ^ John Pike. "CGN 25 Bainbridge class". Global security.
- ^ "Nuclear power for surface combatants". Defense media network.
- ^ a b Pike, J. "SSV-33 Project 1941". GlobalSecurity.org. Retrieved 30 October 2015.
- ^ "Russian media: nuclear torpedo can destroy the US, Europe, the world". Business Insider.
- ^ "Shipping industry should consider nuclear option for decarbonizing: experts | S&P Global Platts". www.spglobal.com. 2020-11-04. Retrieved 2020-11-06.
- ^ Chen, Stephen (2023-12-05). "Chinese shipyard unveils plans for world's first nuclear container powered by cutting-edge molten salt reactor". South China Morning Post. Retrieved 2023-12-07.
- ^ Cleveland, Cutler J, ed. (2004). Encyclopedia of Energy. Vol. 1–6. Elsevier. pp. 336–340. ISBN 978-0-12-176480-7.
- ^ "На ледоколе 'Арктика' поднят российский флаг". sudostroenie.info (in Russian). 2020-10-21. Retrieved 2021-02-07.
- ^ "Nuclear-powered icebreaker Ural of Project 22220 leaves Murmansk for the first operational voyage". PortNews. 2 December 2022. Retrieved 4 December 2022.
References
[edit]- AFP, 11 November 1998; in "Nuclear Submarines Provide Electricity for Siberian Town," FBIS-SOV-98-315, 11 November 1998.
- ITAR-TASS, 11 November 1998; in "Russian Nuclear Subs Supply Electricity to Town in Far East," FBIS-SOV-98-316, 12 November 1998.
- Harold Wilson's plan BBC News story
- Sarkisov, Ashot A.; Tournyol du Clos, Alain, eds. (1999). Analysis of Risks Associated with Nuclear Submarine Decommissioning, Dismantling and Disposal. NATO Science Partnership Subseries 1: Disarmament Technologies. Vol. 24. Dordrecht: Springer. ISBN 978-0-7923-5598-4.