ACR Journal

February | March 2021 REFRIGERANTS 30 Tim Mitchell, Sales Director of Klima-Therm says it pays to consider natural refrigerants in heat pump applications It pays to act naturally Volume 7 No.2 Heat pumps are set to play a significant role in the decarbonisation of heat. However, as they are rolled out on a larger scale, the problem of harmful refrigerants leaking into the atmosphere becomes more significant. Carbon dioxide (CO 2 ) can be viewed as both hero and villain in relation to the environment. On the one hand, this ubiquitous chemical compound is the most noteworthy long lived greenhouse gas in our planet’s atmosphere and, therefore, a big contributor to global warming. On the other, using CO 2 as a natural refrigerant in air conditioning systems can help save energy and reduce the carbon emissions that increase the likelihood of global warming. Liquid and solid CO 2 are significant refrigerants, Solid carbon dioxide – also known as ‘dry ice’ – is particularly useful in the food and drink sector or in medical applications (such as vaccine distribution) for small shipments where refrigeration equipment is impractical. Liquid CO 2 , also known as R744, was often used as a refrigerant before the discovery of R12 (freon), whose use was banned in 1996 because of its harmful e‡ects on the ozone layer. However, over time, it fell out of use. Now, CO 2 is enjoying something of a renaissance because it is less damaging to the environment than many alternative refrigerants currently available. Indeed, its environmental advantages (see the box)