Technical
REDUCING THE ENVIRONMENTAL IMPACT OF HVAC SYSTEMS BY USING R-32 REFRIGERANT
R32 White Paper by Daikin Corporation from 32Reasons . com
Hydrofluorocarbons ( HFCs ), as the name suggests , are compounds containing hydrogen , fluorine , and carbon . They are used for residential and commercial heating , ventilation , and air conditioning ( HVAC ) as refrigerants , by firefighters as a fire suppressant , and in aerosols as propellants .
HFCs are also greenhouse gases often described in terms of their global warming potential ( GWP ), which is the tendency of a substance to persist in the environment while absorbing energy and , thus , retain higher energy and temperatures in the atmosphere .
GWP ratings for substances and material that contribute to the potential of global warming are developed by the Intergovernmental Panel on Climate Change ( IPCC ), a United Nations body responsible for assessing the science related to climate change . 1
GWP uses the same scale to evaluate all substances and materials , making comparisons of direct emissions of refrigerants easy . For example , R410A - a commonly used HFC refrigerant over the past two decades - has a GWP of 2088 , which suggests that each kilogram of R410A emitted to the atmosphere is equivalent to 2088 kilograms of CO 2 emissions . Different refrigerants have different GWPs :
To estimate the total emissions-related effects of a refrigerant ’ s use in HVAC systems , environmental researchers often employ a methodology known as Life Cycle Climate Performance ( LCCP ) modelling . LCCP modelling estimates the total direct and indirect greenhouse gas emissions over an HVAC ’ s system ’ s lifetime , from manufacturing to disposal and recycling .
Put differently , an LCCP analysis considers a refrigerant ’ s physical properties and thermodynamic performance as well as the impacts of that refrigerant ’ s use in an HVAC system to estimate total CO 2 equivalent emissions over that HVAC system ’ s lifetime . R-32 ’ s properties can help HVAC engineers design systems that have a lower greenhouse gas emission impact than R410A . R-32 has greater latent heat capacity than R410A , which means that R-32 systems could be designed to achieve the same capacity performance by circulating less refrigerant at a lower flow rate through the compressor . And a lower charge of R-32 refrigerant in
R32 , or difluoromethane ( CH2F2 ), is an HFC refrigerant with a GWP of 675 , which is markedly lower than that of R410A and many other commonly used refrigerants . However , GWP is only one refrigerant property and not the only measure of a refrigerant ’ s environmental impact when employed in HVAC systems .
“ An LCCP analysis considers a refrigerant ’ s physical properties and thermodynamic performance as well as the impacts of that refrigerant ’ s use in an HVAC system to estimate total CO 2 equivalent emissions over that HVAC system ’ s lifetime .”
www . refrigerationandaircon . co . za RACA Journal I February 2023 47