Nuclear marine propulsion#Civilian nuclear ships

Most naval nuclear reactors are of the 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.{{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}} 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 {{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}}

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.Viren Chopra, Rob Houston (ed), DK Eyewitness Books: Transportation, Penguin, 2012, {{ISBN|1465408894}} page 60

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|date=August 2019}}

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 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|date=August 2019}}

Marine-type reactors differ from land-based commercial electric power reactors in several respects.{{citation_needed|date=August 2019}}

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|date=August 2019}}

File:Nuclear fuel element.jpg

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,{{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 }} in which the resulting smaller core is quieter in operation (a big advantage to a submarine).{{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}} 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.{{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}}

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|date=August 2019}}

Decommissioning nuclear-powered submarines has become a major task for U.S. and Russian navies.Sarkisov and Tournyol du Clos (1999), p. 3. 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).Sarkisov and Tournyol du Clos (1999), p. 3-4. 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}}

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|date=August 2019}}

In 2010, Lloyd's Register was investigating the possibility of civilian nuclear marine propulsion and rewriting draft rules (see text under Merchant Ships).{{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}}.{{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}}{{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}}

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.{{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}} 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{{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}} but was never ratified owing to disagreement on the inclusion of warships under the convention.{{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 }} Nuclear reactors under United States jurisdiction are insured by the provisions of the Price–Anderson Act.{{citation_needed|date=August 2019}}

File:USS Nimitz (CVN-68) with California (CGN-36) and South Carolina (CGN-37) c1976.jpg

By 1990, there were more nuclear reactors powering ships (mostly military) than there were generating electric power in commercial power plants worldwide.{{cite journal |title=Nuclear Weapons at Sea |journal=Bulletin of the Atomic Scientists |date=September 1990 |pages=48–49}}

Under the direction of U.S. Navy Captain (later Admiral) Hyman G. Rickover,{{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}} 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.

{{Further|Nuclear submarine}}

File:FS Saphir 06.jpg, its home port, after Mission Héraclès]]

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).{{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}}

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.{{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}}

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.{{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}}

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}}

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|date=August 2019}}

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|date=August 2019}}

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}}

The United States and France have built nuclear aircraft carriers.

File:Charles De Gaulle (R91) underway 2009.jpg]]

The sole French nuclear aircraft carrier example is {{ship|French aircraft carrier|Charles de Gaulle||2}}, commissioned in 2001 (a successor is planned).{{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/}}

The French carrier is 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 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.{{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 }}

The United States Navy operates 11 carriers, all nuclear-powered:{{Cite web|title=Naval Vessel Register|url=https://www.nvr.navy.mil/NVRSHIPS/ACTIVEINCOMMISSION.HTML|archive-url=https://web.archive.org/web/20161024094308/http://www.nvr.navy.mil/NVRSHIPS/ACTIVEINCOMMISSION.HTML|url-status=dead|archive-date=October 24, 2016|access-date=2020-06-01}}

• {{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.{{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}}
• {{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 reactors providing steam to four steam turbines.
• {{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.

File:Tactical exercises of the Russian Navy.jpg

{{see also|Kirov-class battlecruiser}}

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" ({{langx|ru|тяжёлый атомный ракетный крейсер}}). The ships are often referred to as battlecruisers by Western defence commentators due to their size and general appearance.Armi da guerra, De Agostini, Novara, 1985.

{{see also|Nuclear powered cruisers of the United States Navy}}

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.{{cite web|url=http://navysite.de/cg/cgn9.htm|title=USS Long Beach (CGN 9)}} She was followed a year later by USS Bainbridge (DLGN-25). While Long Beach was designed and built as a cruiser,{{cite web|url=http://www.globalsecurity.org/military/systems/ship/cgn-9.htm|title=CGN-9 Long Beach|author=John Pike}} Bainbridge began life as a frigate, though at that time the Navy was using the hull code "DLGN" for "destroyer leader, guided missile, nuclear".{{cite web | work = Global security |url = http://www.globalsecurity.org/military/systems/ship/cgn-25.htm |title=CGN 25 Bainbridge class|author=John Pike}}

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{{cite web | work = Defense media network |url = http://www.defensemedianetwork.com/stories/nuclear-power-for-surface-combatants/2/|title=Nuclear power for surface combatants}} and they were all retired between 1993 and 1999.{{citation_needed|date=August 2019}}

File:Soviet command ship SSV-33.jpg

{{see also|Soviet communications ship SSV-33}}

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 {{sclass|Kirov|battlecruiser|1}}s with nuclear marine propulsion.{{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}} SSV-33 served in electronic intelligence, missile tracking, space tracking, and communications relay roles. Due to high operating costs, SSV-33 was laid up.

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}}

{{see also|Status-6 Oceanic Multipurpose System}}

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 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.{{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 }}

File:Ns-savanna-eng.jpg

The following are ships that are or were in commercial or civilian use and have nuclear marine propulsion.

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 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}}

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. 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}}

Nuclear propulsion has been proposed again on the wave of decarbonization of marine shipping, which accounts for 3–4% of global greenhouse gas emissions.{{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}}

• USNS American Explorer; United States tanker, converted to conventional power while under construction
• {{ship||Mutsu|nuclear ship|2}}, Japan (1970–1992); never carried commercial cargo, rebuilt as diesel engine powered RV Mirai in 1996
• {{ship||Otto Hahn|ship|2}}, Germany (1968–1979); re-powered with diesel engine in 1979
• {{ship|NS|Savannah}}, United States (1962–1972)
• Sevmorput, Russia (1988–present), ice-strengthened nuclear-powered lighter aboard ship (LASH) carrier

In December 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.{{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}}

{{main|Nuclear-powered icebreaker}}

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|date=August 2019}}

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 {{sclass|Arktika|icebreaker|4}} 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|date=August 2019}}

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.{{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}}

All nuclear-powered icebreakers have been commissioned by the Soviet Union or Russia.{{citation_needed|date=August 2019}}

• {{ship||Lenin|1957 icebreaker|2}} (1959–1989; museum ship)
• {{ship||Arktika|1972 icebreaker|2}} (1975–2008; decommissioned)
• {{ship||Sibir|1977 icebreaker|2}} (1977–1992; scrapped)
• {{ship||Rossiya|1983 icebreaker|2}} (1985–2013; decommissioned)
• {{ship||Taymyr|1987 icebreaker|2}} (1989–present)
• {{ship||Sovetskiy Soyuz|icebreaker|2}} (1989–2014; decommissioned)
• {{ship||Vaygach|1989 icebreaker|2}} (1990–present)
• {{ship||Yamal|icebreaker|2}} (1992–present)
• {{ship||50 Let Pobedy}} (2007–present)
• {{ship||Arktika|2016 icebreaker|2}} (2020–present){{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}}
• {{ship||Sibir|2017 icebreaker|2}} (2021–present)
• {{ship||Ural|icebreaker|2}} (2022–present){{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}}
• {{ship||Yakutiya|icebreaker|2}} (2024–present)

• 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

{{reflist}}

{{refbegin}}

• 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.
• [http://news.bbc.co.uk/1/hi/northern_ireland/4132635.stm Harold Wilson's plan] BBC News story
• {{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}}

{{refend}}

• [http://www.world-nuclear.org/ The World Nuclear Association]
• [https://web.archive.org/web/20070726214243/https://nnptc.cnet.navy.mil/ Naval Nuclear Power Training Command]

{{Nuclear propulsion}}

{{Authority control}}

Category:Marine propulsion

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Marine propulsion