Editing Steamship (section)

==Decline of the steamship==
{{Unreferenced section|date=October 2021}}
By [[World War II]], steamers still constituted 73% of world's tonnage, and similar percentage remained in early 1950s.<ref name=blus/> The decline of the steamship began soon thereafter. Many had been lost in the war, and marine [[diesel engine]]s had finally matured as an economical and viable alternative to steam power. The diesel engine had far better [[thermal efficiency]] than the [[reciprocating steam engine]], and was far easier to control. Diesel engines also required far less supervision and maintenance than steam engines, and as an internal combustion engine it did not need boilers or a water supply, therefore was more space efficient and cheaper to build.

The [[Liberty ship]]s were the last major steamship class equipped with reciprocating engines. The last [[Victory ship]]s had already been equipped with marine diesels, and diesel engines superseded both steamers and [[windjammer]]s soon after World War Two. Most steamers were used up to their maximum economical life span, and no commercial ocean-going steamers with reciprocating engines have been built since the 1960s.

Most larger warships of the world's navies were propelled by steam turbines burning bunker fuel in both World Wars, apart from obsolete ships with reciprocating machines from the turn of the century, and rare cases of usage of diesel engines in larger warships. Steam turbines burning fuel remained in warship construction until the end of the [[Cold War]] (eg. Russian aircraft carrier [[Russian aircraft carrier Admiral Kuznetsov|''Admiral Kuznetsov'']]), because of needs of high power and speed, although from 1970s they were mostly replaced by [[gas turbine]]s. Large naval vessels and submarines continue to be operated with steam turbines, using [[nuclear marine propulsion|nuclear reactors]] to boil the water.
[[NS Savannah|NS ''Savannah'']], was the first nuclear-powered cargo-passenger ship, and was built in the late 1950s as a demonstration project for the potential use of nuclear energy.<ref name=Sun08>{{cite news |url=https://pqasb.pqarchiver.com/baltsun/access/1477681101.html?FMT=ABS |archive-url=https://archive.today/20130201103126/http://pqasb.pqarchiver.com/baltsun/access/1477681101.html?FMT=ABS |url-status=dead |archive-date=February 1, 2013 |first=Laura |last=McCandlish |title=Savannah calls on Baltimore |newspaper=[[The Baltimore Sun]] |date=13 May 2008 |page=D1 }}{{link note |note=Purchase required |date=September 2012}}</ref>

Thousands of Liberty Ships (powered by steam piston engines) and Victory Ships (powered by steam turbine engines) were built in World War II. A few of these survive as floating museums and sail occasionally: {{SS|Jeremiah O'Brien}}, {{SS|John W. Brown}}, {{SS|American Victory}}, {{SS|Lane Victory}}, and {{SS|Red Oak Victory}}.

A steam turbine ship can be either direct propulsion (the turbines, equipped with a reduction gear, rotate directly the propellers), or [[turboelectric]] (the turbines rotate electric generators, which in turn feed electric motors operating the propellers).<ref>{{Cite web |last=Czarnecki |first=Joseph |title=Turboelectric Drive in American Capital Ships |url=http://www.navweaps.com/index_tech/tech-038.php}}</ref>

While steam turbine-driven merchant ships such as the [[Algol-class vehicle cargo ship|''Algol''-class cargo ships]] (1972–1973), ALP Pacesetter-class container ships (1973–1974)<ref>{{cite web |url=http://aplinfo.apl.com/history/html/timeline_03.html#2 |title=APL:History - Timeline: 1960-Present, 1970 |date=September 2014 |access-date=2014-09-23 |archive-date=2017-08-30 |archive-url=https://web.archive.org/web/20170830084440/http://aplinfo.apl.com/history/html/timeline_03.html#2 |url-status=dead }}</ref><ref>{{cite web |url=http://aplinfo.apl.com/history/html/timeline_featured.html#9 |title=APL:History - Featured Vessels, President Jefferson |date=September 2014 |access-date=2014-09-23 |archive-date=2017-08-30 |archive-url=https://web.archive.org/web/20170830051651/http://aplinfo.apl.com/history/html/timeline_featured.html#9 |url-status=dead }}</ref> and [[very large crude carrier]]s were built until the 1970s, the use of steam for marine propulsion in the commercial market has declined dramatically due to the development of more efficient [[diesel engine]]s. One notable exception are [[LNG carrier]]s which use boil-off gas from the cargo tanks as fuel.<ref name=blus>{{cite magazine |author=Marek Błuś|title =Co się stało z parowcami? Zmierzch historycznego napędu|trans-title=What happened to steamers? A decline of the historical propulsion|magazine = Morza, Statki i Okręty |volume = 2/2003 (39)|date=2003|pages=85–86|lang=pl}}</ref> However, even there the development of dual-fuel engines has pushed steam turbines into a niche market with about 10% market share in newbuildings in 2013. Lately, there has been some development in hybrid power plants where the steam turbine is used together with gas engines.<ref>[http://www.mpropulsion.com/news/view,is-there-still-a-commercial-future-for-marine-steam-turbines_42383.htm Is there still a commercial future for marine steam turbines?] {{Webarchive|url=https://web.archive.org/web/20170124072614/http://www.mpropulsion.com/news/view,is-there-still-a-commercial-future-for-marine-steam-turbines_42383.htm |date=2017-01-24 }} Marine Propulsion & Auxiliary Machinery, 30 March 2016. {{retrieved|access-date=2017-03-11}}</ref>  As of August 2017 the newest class of Steam Turbine ships are the [[Seri Camellia class LNG carriers|''Seri Camellia''-class LNG carriers]] built by Hyundai Heavy Industries (HHI) starting in 2016 and comprising five units.<ref>[http://www.motorship.com/news101/lng/versatile-lng-carrier-series-for-malaysia Versatile LNG carrier series for Malaysia] The Motorship: insight for marine technology professionals 04AUG2017. {{retrieved|access-date=2017-08-05}}</ref>

Most steamships today are powered by [[steam turbine]]s. [[Nuclear marine propulsion|Nuclear powered ships]] are basically steam turbine vessels. The boiler is heated, not by [[heat of combustion]], but by the heat generated by nuclear reactor. Most atomic-powered ships today are either [[aircraft carrier]]s or [[submarine]]s.