Editing Refrigeration (section)

==History==
{{For timeline|Timeline of low-temperature technology}}

===Earliest forms of cooling===
The seasonal harvesting of snow and ice is an ancient practice estimated to have begun earlier than 1000 BC.<ref name=":0">{{cite book|last=Neuburger|first=Albert|title=The technical arts and sciences of the ancients|year=2003|publisher=Kegan Paul|location=London|isbn=978-0-7103-0755-2|page=122}}</ref> A Chinese collection of lyrics from this time period known as the ''[[Sleaping]]'', describes religious ceremonies for filling and emptying ice cellars. However, little is known about the construction of these ice cellars or the purpose of the ice. The next ancient society to record the harvesting of ice may have been the Jews in the book of Proverbs, which reads, "As the cold of snow in the time of harvest, so is a faithful messenger to them who sent him." Historians have interpreted this to mean that the Jews used ice to cool beverages rather than to preserve food. Other ancient cultures such as the Greeks and the Romans dug large snow pits insulated with grass, chaff, or branches of trees as cold storage. Like the Jews, the Greeks and Romans did not use ice and snow to preserve food, but primarily as a means to cool beverages. Egyptians cooled water by evaporation in shallow earthen jars on the roofs of their houses at night. The ancient people of India used this same concept to produce ice. The Persians stored ice in a pit called a [[Yakhchal]] and may have been the first group of people to use cold storage to preserve food. In the Australian outback before a reliable electricity supply was available many farmers used a [[Coolgardie safe]], consisting of a box frame with [[hessian fabric|hessian]] (burlap) sides soaked in water. The water would evaporate and thereby cool the interior air, allowing many perishables such as fruit, butter, and cured meats to be kept.<ref>{{cite book|last=Neuburger|first=Albert|title=The technical arts and sciences of the ancients|year=2003|publisher=Kegan Paul|location=London|isbn=978-0-7103-0755-2|pages=122–124}}</ref><ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=5–6}}</ref>

===Ice harvesting===
{{See also|Ice cutting|Ice trade}}
[[File:Ice Harvesting, Massachusetts, early 1850s.jpg|thumb|Ice harvesting in [[Massachusetts]], 1852, showing the [[railroad]] line in the background, used to transport the ice.]]
Before 1830, few Americans used ice to refrigerate foods due to a lack of ice-storehouses and iceboxes. As these two things became more widely available, individuals used axes and saws to [[ice cutting|harvest ice]] for their storehouses. This method proved to be difficult, dangerous, and certainly did not resemble anything that could be duplicated on a commercial scale.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=8–11}}</ref>

Despite the difficulties of harvesting ice, Frederic Tudor thought that he could capitalize on this new commodity by harvesting ice in New England and shipping it to the Caribbean islands as well as the southern states. In the beginning, Tudor lost thousands of dollars, but eventually turned a profit as he constructed icehouses in Charleston, Virginia and in the Cuban port town of Havana. These icehouses as well as better insulated ships helped reduce ice wastage from 66% to 8%. This efficiency gain influenced Tudor to expand his ice market to other towns with icehouses such as New Orleans and Savannah. This ice market further expanded as harvesting ice became faster and cheaper after one of Tudor's suppliers, Nathaniel Wyeth, invented a horse-drawn ice cutter in 1825. This invention as well as Tudor's success inspired others to get involved in the [[ice trade]] and the ice industry grew.

Ice became a mass-market commodity by the early 1830s with the price of ice dropping from six cents per pound to a half of a cent per pound. In New York City, ice consumption increased from 12,000 tons in 1843 to 100,000 tons in 1856. Boston's consumption leapt from 6,000 tons to 85,000 tons during that same period. Ice harvesting created a "cooling culture" as majority of people used ice and iceboxes to store their dairy products, fish, meat, and even fruits and vegetables. These early cold storage practices paved the way for many Americans to accept the refrigeration technology that would soon take over the country.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=11–13}}</ref><ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=20–23|edition=1st Harvard University Press pbk.}}</ref>

===Refrigeration research===
[[File:William Cullen.jpg|thumb|upright|[[William Cullen]], the first to conduct experiments into artificial refrigeration.]]
The history of artificial refrigeration began when Scottish professor [[William Cullen]] designed a small refrigerating machine in 1755. Cullen used a pump to create a partial [[vacuum]] over a container of [[diethyl ether]], which then [[boiling point|boiled]], absorbing [[heat of vaporization|heat]] from the surrounding air.<ref>{{cite book|last=Arora|first=Ramesh Chandra|title=Refrigeration and Air Conditioning|publisher=PHI Learning|location=New Delhi|isbn=978-81-203-3915-6|page=3|chapter=Mechanical vapour compression refrigeration|year=2012}}</ref> The experiment even created a small amount of ice, but had no practical application at that time.

In 1758, [[Benjamin Franklin]] and [[John Hadley (chemist)|John Hadley]], professor of chemistry, collaborated on a project investigating the principle of evaporation as a means to rapidly cool an object at [[Cambridge University]], [[England]]. They confirmed that the evaporation of highly volatile liquids, such as alcohol and ether, could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to quicken the evaporation; they lowered the temperature of the thermometer bulb down to {{convert|7|°F|°C|abbr=on|order=flip}}, while the ambient temperature was {{convert|65|°F|°C|abbr=on|order=flip}}. They noted that soon after they passed the freezing point of water {{convert|0|°C|°F|abbr=on}}, a thin film of ice formed on the surface of the thermometer's bulb and that the ice mass was about a {{convert|1/4|in|mm|order=flip}} thick when they stopped the experiment upon reaching {{convert|7|°F|°C|abbr=on|order=flip}}. Franklin wrote, "From this experiment, one may see the possibility of freezing a man to death on a warm summer's day".<ref>[http://www.historycarper.com/resources/twobf3/letter1.htm Cooling by Evaporation (Letter to John Lining)] {{webarchive|url=https://web.archive.org/web/20110128075748/http://www.historycarper.com/resources/twobf3/letter1.htm |date=2011-01-28}}. Benjamin Franklin, London, June 17, 1758</ref> In 1805, American inventor [[Oliver Evans]] described a closed [[vapor-compression refrigeration]] cycle for the production of ice by ether under vacuum.

In 1820, the English scientist [[Michael Faraday]] liquefied [[ammonia]] and other gases by using high pressures and low temperatures, and in 1834, an American expatriate to Great Britain, [[Jacob Perkins]], built the first working vapor-compression refrigeration system in the world. It was a closed-cycle that could operate continuously, as he described in his patent:
:I am enabled to use volatile fluids for the purpose of producing the cooling or freezing of fluids, and yet at the same time constantly condensing such volatile fluids, and bringing them again into operation without waste.

His prototype system worked although it did not succeed commercially.<ref name=burstall>{{cite book |last= Burstall |first= Aubrey F. |year= 1965 |title= A History of Mechanical Engineering |publisher=The MIT Press |isbn= 978-0-262-52001-0}}</ref>

In 1842, a similar attempt was made by American physician, [[John Gorrie]],<ref>{{Cite web|url=https://pdfpiw.uspto.gov/.piw?Docid=00008080&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%2526Sect2%3DHITOFF%2526d%3DPALL%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r%3D1%2526f%3DG%2526l%3D50%2526s1%3D0008080.PN.%2526OS%3DPN%2F0008080%2526RS%3DPN%2F0008080&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|title=Patent Images}}</ref> who built a working prototype, but it was a commercial failure. Like many of the medical experts during this time, Gorrie thought too much exposure to tropical heat led to mental and physical degeneration, as well as the spread of diseases such as malaria.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=23|edition=1st Harvard University Press pbk.}}</ref> He conceived the idea of using his refrigeration system to cool the air for comfort in homes and hospitals to prevent disease. American engineer [[Alexander Twining]] took out a British patent in 1850 for a vapour compression system that used ether.

The first practical vapour-compression refrigeration system was built by [[James Harrison (engineer)|James Harrison]], a British journalist who had emigrated to [[Australia]]. His 1856 patent was for a vapour-compression system using ether, alcohol, or ammonia. He built a mechanical ice-making machine in 1851 on the banks of the Barwon River at Rocky Point in [[Geelong]], [[Victoria (Australia)|Victoria]], and his first commercial ice-making machine followed in 1854. Harrison also introduced commercial vapour-compression refrigeration to breweries and meat-packing houses, and by 1861, a dozen of his systems were in operation. He later entered the debate of how to compete against the American advantage of unrefrigerated [[beef]] sales to the [[United Kingdom]]. In 1873 he prepared the sailing ship ''Norfolk'' for an experimental beef shipment to the United Kingdom, which used a cold room system instead of a refrigeration system. The venture was a failure as the ice was consumed faster than expected.

[[File:AppareilCarré.jpg|thumb|left|[[Ferdinand Carré]]'s ice-making device]]
The first [[absorption refrigeration|gas absorption]] refrigeration system using gaseous ammonia dissolved in water (referred to as "aqua ammonia") was developed by [[Ferdinand Carré]] of France in 1859 and patented in 1860. [[Carl von Linde]], an engineer specializing in [[steam locomotive]]s and professor of engineering at the [[Technische Universität München|Technological University of Munich]] in Germany, began researching refrigeration in the 1860s and 1870s in response to demand from brewers for a technology that would allow year-round, large-scale production of [[lager]]; he patented an improved method of liquefying gases in 1876.<ref>{{cite episode |title= Eat, Drink, and Be Merry |series= Connections |series-link=Connections (British documentary)|credits= [[James Burke (science historian)|James Burke]] |network=BBC |date=1979 |number= 8|minutes=41–49 |language=en}}</ref> His new process made possible using gases such as [[ammonia]], [[sulfur dioxide]] (SO<sub>2</sub>) and [[methyl chloride]] (CH<sub>3</sub>Cl) as refrigerants and they were widely used for that purpose until the late 1920s.

[[Thaddeus Lowe]], an American balloonist, held several patents on ice-making machines. His "Compression Ice Machine" would revolutionize the cold-storage industry. In 1869, he and other investors purchased an old steamship onto which they loaded one of Lowe's refrigeration units and began shipping fresh fruit from New York to the Gulf Coast area, and fresh meat from Galveston, Texas back to New York, but because of Lowe's lack of knowledge about shipping, the business was a costly failure.

===Commercial use===
{{See also|Cold chain|Refrigerator}}
[[File:Early refrigerator car design circa 1870.jpg|thumb|An 1870 refrigerator car design. Hatches in the roof provided access to the tanks for the storage of harvested ice at each end.|right]]
[[File:AndrewMuhlPatent02.png|thumb|Icemaker Patent by Andrew Muhl, dated December 12, 1871.]]
In 1842, [[John Gorrie]] created a system capable of refrigerating water to produce ice. Although it was a commercial failure, it inspired scientists and inventors around the world. France's Ferdinand Carre was one of the inspired and he created an ice producing system that was simpler and smaller than that of Gorrie. During the Civil War, cities such as New Orleans could no longer get ice from New England via the coastal ice trade. Carre's refrigeration system became the solution to New Orleans' ice problems and, by 1865, the city had three of Carre's machines.<ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=25}}</ref> In 1867, in San Antonio, Texas, a French immigrant named Andrew Muhl built an ice-making machine to help service the expanding beef industry before moving it to Waco in 1871. In 1873, the patent for this machine was contracted by the Columbus Iron Works, a company acquired by the W.C. Bradley Co., which went on to produce the first commercial ice-makers in the US.

By the 1870s, breweries had become the largest users of harvested ice. Though the ice-harvesting industry had grown immensely by the turn of the 20th century, pollution and sewage had begun to creep into natural ice, making it a problem in the metropolitan suburbs. Eventually, breweries began to complain of tainted ice. Public concern for the purity of water, from which ice was formed, began to increase in the early 1900s with the rise of germ theory. Numerous media outlets published articles connecting diseases such as typhoid fever with natural ice consumption. This caused ice harvesting to become illegal in certain areas of the country. All of these scenarios increased the demands for modern refrigeration and manufactured ice. Ice producing machines like that of Carre's and Muhl's were looked to as means of producing ice to meet the needs of grocers, farmers, and food shippers.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=25|edition=1st Harvard University Press pbk.}}</ref><ref>{{cite book|last=Anderson|first=Oscar Edward|title=Refrigeration in America; a history of a new technology and its impact|year=1953|publisher=Published for the University of Cincinnati by Princeton University Press|location=Princeton|isbn=978-0-8046-1621-8|pages=110–111}}</ref>

Refrigerated railroad cars were introduced in the US in the 1840s for short-run transport of dairy products, but these used harvested ice to maintain a cool temperature.<ref>[https://tshaonline.org/handbook/online/articles/dqr01 Refrigeration], Texas State Historical Association.</ref>

[[File:SS Dunedin by Frederick Tudgay.JPG|thumb|left|[[Dunedin (ship)|''Dunedin'']], the first commercially successful refrigerated ship.]]
The new refrigerating technology first met with widespread industrial use as a means to freeze meat supplies for transport by sea in [[reefer ship]]s from the British [[Dominion]]s and other countries to the [[British Isles]]. Although not actually the first to achieve successful transportation of frozen goods overseas (the ''Strathleven'' had arrived at the London docks on 2 February 1880 with a cargo of frozen beef, mutton and butter from Sydney and Melbourne <ref>{{cite book |last1=Munro |first1=J. Forbes |title=Maritime Enterprise and Empire : Sir William MacKinnon and his Business Network,1823-1893 |date=2003 |publisher=Boydell Press |isbn=9780851159355 |page=283 |url=https://books.google.com/books?id=Dm6tSiRizBcC&dq=may+2+1880+frozen+meat+melbourne&pg=PA283}}</ref>), the breakthrough is often attributed to [[William Soltau Davidson]], an entrepreneur who had emigrated to [[New Zealand]]. Davidson thought that Britain's rising population and meat demand could mitigate the slump in world [[wool]] markets that was heavily affecting New Zealand. After extensive research, he commissioned the [[Dunedin (ship)|''Dunedin'']] to be refitted with a compression refrigeration unit for meat shipment in 1881. On February 15, 1882, the ''Dunedin'' sailed for London with what was to be the first commercially successful refrigerated shipping voyage, and the foundation of the refrigerated [[meat industry]].<ref>{{cite book|title=A lasting Legacy – A 125 year history of New Zealand Farming since the first Frozen Meat Shipment|author=Colin Williscroft|publisher=NZ Rural Press Limited|year=2007|url=https://books.google.com/books?id=VTrmMQAACAAJ}}</ref>

''[[The Times]]'' commented "Today we have to record such a triumph over physical difficulties, as would have been incredible, even unimaginable, a very few days ago...". The ''[[Marlborough (1876 ship)|Marlborough]]''—sister ship to the ''Dunedin'' – was immediately converted and joined the trade the following year, along with the rival [[New Zealand Shipping Company]] vessel ''Mataurua'', while the German Steamer ''Marsala'' began carrying frozen New Zealand lamb in December 1882. Within five years, 172 shipments of frozen meat were sent from New Zealand to the United Kingdom, of which only 9 had significant amounts of meat condemned. Refrigerated shipping also led to a broader meat and dairy boom in [[Australasia]] and South America. [[J & E Hall]] of [[Dartford]], England outfitted the ''SS Selembria'' with a vapor compression system to bring 30,000 carcasses of [[mutton]] from the [[Falkland Islands]] in 1886.<ref>{{Cite web|url=http://www.jehall.com/about-jeh-group/history|title=Our History &#124; Refrigeration Solutions &#124; J&E Hall|website=www.jehall.com}}</ref> In the years ahead, the industry rapidly expanded to Australia, Argentina and the United States.

By the 1890s, refrigeration played a vital role in the distribution of food. The meat-packing industry relied heavily on natural ice in the 1880s and continued to rely on manufactured ice as those technologies became available.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=142|edition=1st Harvard University Press pbk.}}</ref> By 1900, the meat-packing houses of Chicago had adopted ammonia-cycle commercial refrigeration. By 1914, almost every location used artificial refrigeration. The [[Meat packing industry#Meatpackers|major meat packers]], Armour, Swift, and Wilson, had purchased the most expensive units which they installed on train cars and in branch houses and storage facilities in the more remote distribution areas.

By the middle of the 20th century, refrigeration units were designed for installation on trucks or lorries. Refrigerated vehicles are used to transport perishable goods, such as frozen foods, fruit and vegetables, and temperature-sensitive chemicals. Most modern refrigerators keep the temperature between –40 and –20&nbsp;°C, and have a maximum payload of around 24,000&nbsp;kg gross weight (in Europe).

Although commercial refrigeration quickly progressed, it had limitations that prevented it from moving into the household. First, most refrigerators were far too large. Some of the commercial units being used in 1910 weighed between five and two hundred tons. Second, commercial refrigerators were expensive to produce, purchase, and maintain. Lastly, these refrigerators were unsafe. It was not uncommon for commercial refrigerators to catch fire, explode, or leak toxic gases. Refrigeration did not become a household technology until these three challenges were overcome.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=38|edition=1st Harvard University Press pbk.}}</ref>

===Home and consumer use===
[[File:Early household refrigerator in Popular Science 1919.png|thumb|An early example of the [[consumerization]] of mechanical refrigeration that began in the early 20th century. The [[refrigerant]] was [[sulfur dioxide]].]]
[[File:Food into a refrigerator - 20111002.jpg|thumb|A modern home refrigerator]]

During the early 1800s, consumers preserved their food by storing food and ice purchased from ice harvesters in iceboxes. In 1803, Thomas Moore patented a metal-lined butter-storage tub which became the prototype for most iceboxes. These iceboxes were used until nearly 1910 and the technology did not progress. In fact, consumers that used the icebox in 1910 faced the same challenge of a moldy and stinky icebox that consumers had in the early 1800s.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=23, 38|edition=1st Harvard University Press pbk.}}</ref>

General Electric (GE) was one of the first companies to overcome these challenges. In 1911, GE released a household refrigeration unit that was powered by gas. The use of gas eliminated the need for an electric compressor motor and decreased the size of the refrigerator. However, electric companies that were customers of GE did not benefit from a gas-powered unit. Thus, GE invested in developing an electric model. In 1927, GE released the Monitor Top, the first refrigerator to run on electricity.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=43–45|edition=1st Harvard University Press pbk.}}</ref>

In 1930, Frigidaire, one of GE's main competitors, synthesized [[Freon]].<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=44|edition=1st Harvard University Press pbk.}}</ref> With the invention of synthetic refrigerants based mostly on a [[chlorofluorocarbon]] (CFC) chemical, safer refrigerators were possible for home and consumer use. Freon led to the development of smaller, lighter, and cheaper refrigerators. The average price of a refrigerator dropped from $275 to $154 with the synthesis of Freon. This lower price allowed ownership of refrigerators in American households to exceed 50% by 1940.<ref>{{cite book|last=Freidberg|first=Susanne|title=Fresh: a perishable history|year=2010|publisher=Belknap|location=Cambridge, MA|isbn=978-0-674-05722-7|pages=45|edition=1st Harvard University Press pbk.}}</ref> Freon is a trademark of the DuPont Corporation and refers to these CFCs, and later hydro chlorofluorocarbon (HCFC) and hydro fluorocarbon (HFC), refrigerants developed in the late 1920s. These refrigerants were considered — at the time — to be less harmful than the commonly-used refrigerants of the time, including methyl formate, ammonia, methyl chloride, and sulfur dioxide. The intent was to provide refrigeration equipment for home use without danger. These CFC refrigerants answered that need. In the 1970s, though, the compounds were found to be reacting with atmospheric ozone, an important protection against solar ultraviolet radiation, and their use as a refrigerant worldwide was curtailed in the [[Montreal Protocol]] of 1987.