Editing Ethylene glycol (section)

===Coolant and heat-transfer agent===
A major use of ethylene glycol is as an antifreeze agent in [[coolant]]s. This can be useful for automobiles and [[air-conditioning]] systems that either have external [[chiller]]s or [[Air handler|air handlers]], or must cool below the freezing temperature of water. In [[geothermal heating]]/cooling systems, ethylene glycol is the [[fluid]] that transports heat through the use of a [[geothermal heat pump]].  The ethylene glycol either gains energy from the source (lake, ocean, [[water well]]) or dissipates heat to the sink, depending on whether the system is being used for heating or cooling.

Pure ethylene glycol has a [[specific heat capacity]] about one half that of water.  So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water.  A 1:1 mix by mass has a specific heat capacity of about 3140 J/(kg·°C) (0.75 BTU/(lb·°F)), three quarters that of pure water, thus requiring increased flow rates in same-system comparisons with water.

The mixture of ethylene glycol with water provides additional benefits to coolant and antifreeze solutions, such as preventing corrosion and acid degradation, as well as inhibiting the growth of most microbes and fungi.<ref>{{Cite web|url=http://www.hydratechglobal.net/technical/Ethylene+Glycol/58/en|title=Hydratech - Specialist Fluid Solutions|website=www.hydratechglobal.net|access-date=2020-02-24|archive-date=2021-05-14|archive-url=https://web.archive.org/web/20210514041855/http://www.hydratechglobal.net/technical/Ethylene+Glycol/58/en|url-status=dead}}</ref> Mixtures of ethylene glycol and water are sometimes informally referred to in industry as glycol concentrates, compounds, mixtures, or solutions.

Table of thermal and physical properties of saturated liquid ethylene glycol:<ref>{{Cite book |last=Holman |first=Jack P. |title=Heat Transfer |publisher=McGraw-Hill Companies, Inc |year=2002 |isbn=9780072406559 |edition=9th |location=New York, NY |pages=600–606 |language=English}}</ref><ref>{{Cite book |author=Frank P. Incropera, David P. Dewitt, heodore L. Bergman, Adrienne S. Lavigne |title=Fundamentals of Heat and Mass Transfer |publisher=John Wiley and Sons, Inc. |year=2007 |isbn=9780471457282 |edition=6th |location=Hoboken, NJ |pages=941–950 |language=English}}</ref>
{|class="wikitable mw-collapsible"
!Temperature (°C)
!Density (kg/m<sup>3</sup>)
!Specific heat (kJ/(kg·K))
!Kinematic viscosity (m<sup>2</sup>/s)
!Conductivity (W/(m⋅K))
!Thermal diffusivity (m<sup>2</sup>/s)
!Prandtl number
!Thermal expansivity (K<sup>−1</sup>)
|-
|0
|1130.75
|2.294
|{{val|7.53E-5}}
|0.242
|{{val|9.34E-8}}
|615
|{{val|6.50E-4}}
|-
|20
|1116.65
|2.382
|{{val|1.92E-5}}
|0.249
|{{val|9.39E-8}}
|204
|{{val|6.50E-4}}
|-
|40
|1101.43
|2.474
|{{val|8.69E-6}}
|0.256
|{{val|9.39E-8}}
|93
|{{val|6.50E-4}}
|-
|60
|1087.66
|2.562
|{{val|4.75E-6}}
|0.26
|{{val|9.32E-8}}
|51
|{{val|6.50E-4}}
|-
|80
|1077.56
|2.65
|{{val|2.98E-6}}
|0.261
|{{val|9.21E-8}}
|32.4
|{{val|6.50E-4}}
|-
|100
|1058.5
|2.742
|{{val|2.03E-6}}
|0.263
|{{val|9.08E-8}}
|22.4
|{{val|6.50E-4}}
|}