RACA Journal June 2024 RACA_June 2024_digital | Page 33

Feature that the gases are handled efficiently and effectively . The team can recover gas cylinders , equipment , and all other necessary items . We even offer a buyback programme , which allows customers to return their empty cylinders and receive a refund .

Some customers may wonder where they can take outdated or contaminated gas . It is important to note that these gases should not be handled by inexperienced individuals or left to accumulate on-site .

One of the key challenges is the mindset of business owners who prioritise profits over environmental responsibility . It is essential to encourage these owners to see the benefits of investing in recovery and to view it as a way to generate income through a higher value service . In some cases , it may be more cost-effective to outsource the recovery process to a specialist company , rather than trying to recover refrigerant in-house .

One issue that arises is when the refrigerant is mixed or blended , making it impossible to separate . It is essential to handle such cases with care , as contaminated refrigerant can cause significant damage . The government may not support the recovery of small amounts of gas , which can lead technicians to recover the gas themselves . This practice can lead to workshops being filled with bottles of recovered refrigerant , which can then be given to recovery companies to dispose of properly .

There are laws and regulations in place that mandate proper recovery and disposal . Failure to comply can lead to fines and other penalties . Therefore , it is important to ensure that all cylinders used for recovery are checked and certified to be safe for reuse .

R32 AND GLOBAL WARMING POTENTIAL According to a White Paper by Daikin Corporation on R32 , hydrofluorocarbons ( HFCs ), as the name suggests , are compounds containing hydrogen , fluorine and carbon . They are used for residential and commercial 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 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 UN body responsible for assessing the science related to climate change .

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 kilogramme of R410A emitted to the atmosphere is equivalent to 2 088kg of CO 2 emissions . Different refrigerants have different GWPs : 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 .

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Presenter Werner Terblanche of A-Gas South Africa describing the Kigali Amendment to the Montreal Protocol phase-out and phasedown regulations .

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 . A lower charge of R-32 refrigerant in comparison to R410A allows HVAC engineers the opportunity to design smaller compressors and coils .

These characteristics of R-32 help give engineers the tools they need to design R-32 systems with energy savings and a reduction in the material used . These indirect benefits can have a significant impact on the environment that are not accounted for in a GWP rating alone .

Daikin lab tests on rooftop systems equipped with inverterdriven compressors and water-cooled chillers found that full-load and part-load efficiency rating metrics improved by up to 12 % by using R-32 as compared to R410A . Daikin engineers have also found that R-32 can be used in heat pump and cooling applications and extreme cold and hot climates with improved performance over R-410A . According to the EIA projections , 94 % of the required energy for operating air-conditioning systems was provided using electricity from non-renewable sources . RACA