Editing Propane (section)

== Uses ==
{{More citations needed|date=April 2019}}

===Portable stoves===
Propane is a popular choice for barbecues and portable stoves because the low [[boiling point]] of {{convert|-42|C|F}} makes it vaporize as soon as it is released from its pressurized container. Therefore, no [[carburetor]] or other vaporizing device is required; a simple metering nozzle suffices.

=== Refrigerant ===

Blends of pure, dry "isopropane" [isobutane/propane mixtures of propane (R-290) and [[isobutane]] (R-600a)] can be used as the circulating refrigerant in suitably constructed compressor-based refrigeration.<ref>{{Cite journal |last=Başaran |first=Anıl |date=August 10, 2023 |title=Experimental investigation of R600a as a low GWP substitute to R134a in the closed-loop two-phase thermosyphon of the mini thermoelectric refrigerator |url=https://www.sciencedirect.com/science/article/abs/pii/S1359431122004550 |url-status=live |archive-url=https://web.archive.org/web/20230811050616/https://www.sciencedirect.com/science/article/abs/pii/S1359431122004550 |archive-date=August 11, 2023 |access-date=2023-08-11 |journal=Applied Thermal Engineering |volume=211 |doi=10.1016/j.applthermaleng.2022.118501 |s2cid=248206074 |language=en-AU }}</ref> Compared to fluorocarbons, propane has a negligible [[ozone depletion potential]] and very low [[global warming potential]] (having a GWP value of 0.072,<ref>[https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Full_Report.pdf Climate Change 2021 – The Physical Science Basis]</ref> 13.9 times lower than the GWP of carbon dioxide) and can serve as a functional replacement for [[Dichlorodifluoromethane|R-12]], [[Chlorodifluoromethane|R-22]], [[1,1,1,2-Tetrafluoroethane|R-134a]], and other [[chlorofluorocarbon]] or [[hydrofluorocarbon]] [[refrigerant]]s in conventional stationary refrigeration and air conditioning systems.<ref>{{cite web|url=http://ec.europa.eu/environment/ozone/pdf/hcfc_technical_meeting_summary.pdf |title=European Commission on retrofit refrigerants for stationary applications |access-date=2010-10-29 |archive-url=https://web.archive.org/web/20090805150605/http://ec.europa.eu/environment/ozone/pdf/hcfc_technical_meeting_summary.pdf |archive-date=August 5, 2009 }}</ref> Because its global warming effect is far less than current refrigerants, propane was chosen as one of five replacement refrigerants approved by the EPA in 2015, for use in systems specially designed to handle its flammability.<ref>{{cite web |last1=Koch |first1=Wendy |title=Why Your Fridge Pollutes and How It's Changing |url=https://www.nationalgeographic.com/science/article/150306-why-your-fridge-pollutes-and-how-its-changing |archive-url=https://web.archive.org/web/20210226092729/https://www.nationalgeographic.com/science/article/150306-why-your-fridge-pollutes-and-how-its-changing |url-status=live |archive-date=February 26, 2021 |publisher=National Geographic |access-date=22 December 2021 |date=March 6, 2015}}</ref>

Such substitution is widely prohibited or discouraged in motor vehicle air conditioning systems, on the grounds that using [[Flammability|flammable]] hydrocarbons in systems originally designed to carry non-flammable refrigerant presents a significant risk of fire or explosion.<ref>{{multiref2
|1={{cite web |url=http://www.epa.gov/ozone/snap/refrigerants/hc12alng.html |title=U.S. EPA hydrocarbon-refrigerants FAQ |publisher=Epa.gov |access-date=2010-10-29 |archive-date=2002-12-31 |archive-url=https://web.archive.org/web/20021231213807/http://www.epa.gov/ozone/snap/refrigerants/hc12alng.html |url-status=dead }}
|2=[https://web.archive.org/web/20080719055123/http://www.vasa.org.au/pdf/memberlibrary/hydrocarbons/hc_white_paper.pdf Compendium of hydrocarbon-refrigerant policy statements, October 2006]. vasa.org.au
|3={{cite web |url=http://www.autoacforum.com/MACS/HCwarning.pdf |title=MACS bulletin: hydrocarbon refrigerant usage in vehicles |access-date=2010-10-29 |url-status=dead |archive-url=https://web.archive.org/web/20110105174944/http://www.autoacforum.com/MACS/HCwarning.pdf |archive-date=2011-01-05 }}
|4={{cite web |url=http://www.sae.org/news/releases/05hydrocarbon_warning.htm |title=Society of Automotive Engineers hydrocarbon refrigerant bulletin |publisher=Sae.org |date=2005-04-27 |access-date=2010-10-29 |archive-url=https://web.archive.org/web/20050505030057/http://www.sae.org/news/releases/05hydrocarbon_warning.htm |archive-date=2005-05-05 |url-status=dead }}
|5={{cite web |url=http://www.shadetreemechanic.com/cc_hydrocarbon_refrigerants.htm |title=Shade Tree Mechanic on hydrocarbon refrigerants |publisher=Shadetreemechanic.com |date=2005-04-27 |access-date=2010-10-29 |archive-date=2010-11-27 |archive-url=https://web.archive.org/web/20101127153510/http://shadetreemechanic.com/cc_hydrocarbon_refrigerants.htm |url-status=dead }}
|6={{cite web |url=http://www.labour.gov.sk.ca/Default.aspx?DN=2fb5ac24-d90e-4408-bf40-559793bd8e96 |title=Saskatchewan Labour bulletin on hydrocarbon refrigerants in vehicles |publisher=Labour.gov.sk.ca |date=2010-06-29 |access-date=2010-10-29 |url-status=dead |archive-url=https://web.archive.org/web/20090701025850/http://www.labour.gov.sk.ca/Default.aspx?DN=2fb5ac24-d90e-4408-bf40-559793bd8e96 |archive-date=2009-07-01 }}
|7=[https://web.archive.org/web/20080719134349/http://www.vasa.org.au/content/refriggas/index.php#Bookmark%202 VASA on refrigerant legality & advisability]. vasa.org.au
|8={{cite web |url=http://www.energy.qld.gov.au/zone_files/petroleum_pdf/safety_alert025.pdf |title=Queensland (Australia) government warning on hydrocarbon refrigerants |publisher=Energy.qld.gov.au |access-date=2010-10-29 |archive-url=https://web.archive.org/web/20081217150006/http://www.energy.qld.gov.au/zone_files/petroleum_pdf/safety_alert025.pdf |archive-date=December 17, 2008 }}}}</ref>

Vendors and advocates of hydrocarbon refrigerants argue against such bans on the grounds that there have been very few such incidents relative to the number of vehicle air conditioning systems filled with hydrocarbons.<ref>{{cite web|url=http://www.parliament.nsw.gov.au/prod/parlment/HansArt.nsf/V3Key/LA19971016015 |title=New South Wales (Australia) Parliamentary record, 16 October 1997 |publisher=Parliament.nsw.gov.au |date=1997-10-16 |access-date=2010-10-29 |url-status=dead |archive-url=https://web.archive.org/web/20090701025536/http://www.parliament.nsw.gov.au/prod/parlment/HansArt.nsf/V3Key/LA19971016015 |archive-date=1 July 2009 }}</ref><ref>{{cite web|url=http://www.parliament.nsw.gov.au/prod/parlment/hansart.nsf/V3Key/LC20000629051 |title=New South Wales (Australia) Parliamentary record, 29 June 2000 |publisher=Parliament.nsw.gov.au |access-date=2010-10-29 |url-status=dead |archive-url=https://web.archive.org/web/20050522080708/http://www.parliament.nsw.gov.au/prod/parlment/hansart.nsf/V3Key/LC20000629051 |archive-date=22 May 2005 }}</ref>

Propane is also instrumental in providing [[off-the-grid]] refrigeration, as the energy source for a [[gas absorption refrigerator]] and is commonly used for camping and recreational vehicles.

It has also been proposed to use propane as a refrigerant in [[Heat pump|heat pumps]].<ref>{{Cite web |last=Everitt |first=Neil |date=2023-03-18 |title=Scientists back propane in heat pumps |url=https://www.coolingpost.com/world-news/scientists-back-propane-in-heat-pumps/ |access-date=2024-03-09 |website=Cooling Post |language=en-GB}}</ref>

=== Domestic and industrial fuel ===
[[File:150 gallon Propane Tank.jpg|thumb|upright|Domestic spherical steel pressure vessel for propane storage]]
Since it can be transported easily, it is a popular fuel for home heat and backup electrical generation in sparsely populated areas that do not have natural gas pipelines. In June 2023, Stanford researchers found propane combustion emitted detectable and repeatable levels of benzene that in some homes raised indoor benzene concentrations above well-established health benchmarks. The research also shows that gas and propane fuels appear to be the dominant source of benzene produced by cooking.<ref>{{Cite journal |last1=Kashtan |first1=Yannai S. |last2=Nicholson |first2=Metta |last3=Finnegan |first3=Colin |last4=Ouyang |first4=Zutao |last5=Lebel |first5=Eric D. |last6=Michanowicz |first6=Drew R. |last7=Shonkoff |first7=Seth B. C. |last8=Jackson |first8=Robert B. |date=June 15, 2023 |title=Gas and Propane Combustion from Stoves Emits Benzene and Increases Indoor Air Pollution |journal=  Environmental Science & Technology|volume=57 |issue=26 |pages=9653–9663 |doi=10.1021/acs.est.2c09289 |pmid=37319002 |pmc=10324305 |bibcode=2023EnST...57.9653K }}</ref>

In rural areas of North America, as well as northern Australia, propane is used to heat livestock facilities, in grain dryers, and other heat-producing appliances. When used for heating or [[grain drying]] it is usually stored in a large, permanently-placed cylinder which is refilled by a propane-delivery truck. {{as of|2014}}, 6.2 million American households use propane as their primary heating fuel.<ref name="Sloan-2016">{{cite web|url=https://www.afdc.energy.gov/uploads/publication/2016_propane_market_outlook.pdf|title=2016 Propane Market Outlook|author1=Sloan, Michael|publisher=Propane Education and Research Council|access-date=19 January 2018}}</ref>

In North America, local delivery trucks with an average cylinder size of {{convert|3,000|USgal|m3}}, fill up large cylinders that are permanently installed on the property, or other service trucks exchange empty cylinders of propane with filled cylinders. Large tractor-trailer trucks, with an average cylinder size of {{convert|10,000|USgal|m3}}, transport propane from the pipeline or refinery to the local bulk plant. The bobtail [[tank truck]] is not unique to the North American market, though the practice is not as common elsewhere, and the vehicles are generally called ''tankers''. In many countries, propane is delivered to end-users via small or medium-sized individual cylinders, while empty cylinders are removed for refilling at a central location.

There are also community propane systems, with a central cylinder feeding individual homes.<ref>{{Cite web|last=Council|first=Propane Education & Research|title=Community Propane Systems {{!}} Propane.com|url=https://propane.com/propane-products/community-propane-systems/|access-date=2021-12-28|website=Propane|language=en}}</ref>

=== Motor fuel ===
{{more citations needed section|date=October 2009}}
{{Main|Autogas}}

In the U.S., over 190,000 on-road vehicles use propane, and over 450,000 forklifts use it for power. It is the third most popular vehicle fuel in the world,<ref name="propane-as-fuel" /> behind [[gasoline]] and [[diesel fuel]]. In other parts of the world, propane used in vehicles is known as autogas. In 2007, approximately 13 million vehicles worldwide use autogas.<ref name="propane-as-fuel">{{cite web|author1=Propane Education |author2=Research Council |name-list-style=amp |title=Autogas |url=http://www.propanecouncil.org/propane-as-fuel/ |publisher=PERC |access-date=2012-05-17 |url-status=dead |archive-url=https://web.archive.org/web/20100923030304/http://www.propanecouncil.org/propane-as-fuel/ |archive-date=September 23, 2010 }}</ref>

The advantage of propane in cars is its liquid state at a moderate pressure. This allows fast refill times, affordable fuel cylinder construction, and price ranges typically just over half that of gasoline. Meanwhile, it is noticeably cleaner (both in handling, and in combustion), results in less engine wear (due to carbon deposits) without diluting engine oil (often extending oil-change intervals), and until recently{{When|date=July 2021}} was relatively low-cost in North America. The [[octane rating]] of propane is relatively high at 110. In the United States the propane fueling infrastructure is the most developed of all alternative vehicle fuels. Many converted vehicles have provisions for topping off from "barbecue bottles". Purpose-built vehicles are often in commercially owned fleets, and have private fueling facilities. A further saving for propane fuel vehicle operators, especially in fleets, is that theft is much more difficult than with gasoline or diesel fuels.

Propane is also used as fuel for [[small engine]]s, especially those used indoors or in areas with insufficient fresh air and ventilation to carry away the more toxic exhaust of an engine running on gasoline or diesel fuel. More recently,{{When|date=July 2021}} there have been lawn-care products like [[string trimmer]]s, [[lawn mowers]] and [[leaf blowers]] intended for outdoor use, but fueled by propane in order to reduce [[air pollution]].<ref>{{Cite web|url=http://www.allpropanemowers.com/wp-content/uploads/2014/06/Facts_About_Propane.pdf|title=Facts About Propane: America's Exceptional Energy|date=April 2001|publisher=National Propane Gas Association|access-date=December 15, 2016|archive-date=December 21, 2016|archive-url=https://web.archive.org/web/20161221104931/http://www.allpropanemowers.com/wp-content/uploads/2014/06/Facts_About_Propane.pdf|url-status=dead}}</ref>

Many heavy-duty highway trucks use propane as a boost, where it is added through the turbocharger, to mix with diesel fuel droplets. Propane droplets' very high hydrogen content helps the diesel fuel to burn hotter and therefore more completely. This provides more torque, more horsepower, and a cleaner exhaust for the trucks. It is normal for a 7-liter medium-duty diesel truck engine to increase fuel economy by 20 to 33 percent when a propane boost system is used. It is cheaper because propane is much cheaper than diesel fuel. The longer distance a cross-country trucker can travel on a full load of combined diesel and propane fuel means they can maintain federal hours of work rules with two fewer fuel stops in a cross-country trip. Truckers, tractor pulling competitions, and farmers have been using a propane boost system for over forty years{{When|date=July 2021}} in North America.

=== Other uses ===
[[File:Propane cylinders type 2012 and 2000 in Tuntorp.jpg|thumb|Cylinders type 2012 containing 2 kg, and type 2000 containing 0.34 kg propane; sizes normally used for [[camping]] devices and hobby projects in workshops.]]
*Propane is the primary flammable gas in [[blowtorch]]es for [[soldering]].
*Propane is used in [[oxy-fuel welding and cutting]]. Propane does not burn as hot as acetylene in its inner cone, and so it is rarely used for welding. Propane, however, has a very high number of BTUs per cubic foot in its outer cone, and so with the right torch (injector style) it can make a faster and cleaner cut than acetylene, and is much more useful for heating and bending than acetylene.
*Propane is used as a feedstock for the production of base [[petrochemical]]s in [[steam cracking]].
*Propane is the primary fuel for [[hot-air balloon]]s.
*It is used in semiconductor manufacture to deposit [[silicon carbide]].
*Propane is commonly used in theme parks and in movie production as an inexpensive, high-energy fuel for explosions and other special effects.
*Propane is used as a propellant, relying on the expansion of the gas to fire the projectile. It does not ignite the gas. The use of a liquefied gas gives more shots per cylinder, compared to a compressed gas.
*Propane is also used as a cooking fuel.
*Propane is used as a propellant for many household aerosol sprays, including shaving creams and air fresheners.
*Propane is a promising feedstock for the production of propylene.{{citation needed|date=January 2023}}
*Liquified propane is used in the extraction of animal fats and vegetable oils.<ref>{{Ullmann|doi=10.1002/14356007.a24_437|title=Solvents|year=2000|last1=Stoye|first1=Dieter|isbn=3527306730}}</ref>