Section 01 Alternatives to HCFCs in the Refrigeration and Air Conditioning Sector 22 Du e to the huge number of applications for refrigeration and air conditioning systems with different operating conditions and requirements, it is practically impossible to find a single ideal refrigerant. The ideal refrigerant would need to have the following properties and characteristics, among others: Zero Ozone Depleting Potential (ODP)■■ Energy efficient = have high Coefficient of Performance ■■(COP), i.e. low indirect Global Warming Impact Zero or low Global Warming Potential (GWP), i.e. low Direct ■■Global Warming Impact Chemically stable at all temperatures and environments■■ including contaminated systems■■ Compatible with all materials■■ metals■■ elastomers (plastic/rubber materials)■■ oil, including suitable miscibility/solubility with oil■■ Non-toxic■■ Non-flammable■■ Low cost■■ Commercially available■■ The above list does not reflect an order of priority as this cannot be defined on a general level. Obviously, refrigerants with high flammability and toxicity can be easily handled in some applications and may be more or less impossible to be applied in others, at least without a significant increase in energy consumption and/or cost. Zero ODP is a legal requirement in many countries already. The total warming impact of a refrigeration air conditioning system will consist of a direct effect from released refrigerants and an indirect effect from carbon dioxide emissions during the production of energy used to operate the system. The combined effect of Direct and Indirect warming effect is often calculated as the Total Equivalent Warming Impact or TEWI (see Abbreviations and definitions) TEWI takes into consideration leakage rates, emissions from the site where systems are scrapped and energy consumption. As these factors are different for each system and difficult to estimate, TEWI is often calculated based on statistical values and experience. The result will be affected by how the different factors are estimated. Factors like leakage and recovery rate are dependent on the quality of installation and service. This will change over time as service is improved through training in combination with regulations that require end-users and contractors to keep records, discourage emissions and enforcement actions. To assume leakage rates of 30% common on many markets or 5% achieved in others will drastically change the balance between direct emissions from leakage and indirect emissions from energy consumption. Few Article 5 countries have so far been successful in implementing functional refrigerant re-use as the system’s total energy efficiency should be measured. A system using a refrigerant with a higher GWGWP can be more energy efficient and have a lower total impact on the climate. Using a lower GWGWP refrigerant in a safe and energy efficient way at an acceptable cost is a preferable solution to using high GWGWP alternatives such as HFCs. HFC emissions must be minimised and should only be used in systems with minimum leaks and where leak controls and recovery schemes are in place. HFCs are among the controlled substances under the Kyoto Protocol and can be expected to be charged with increased regulatory controls in the future. There is always a number of alternative technologies that can be used. The easiest route would seem to be to choose the alternatives that require no or minimal system changes but it is important to realise that new technologies are continually being introduced and that the industry will eventually have to keep its knowledge abreast with these new technologies. An evaluation of environmental impact including energy efficiency, cost, technical as well as safety risks is required. The outcome will be different for different operating conditions and will depend on where the equipment is installed and how it is used. Generalisations often result in poor decisions and that is why it is important to establish industry standards to have acceptable service availability and to make the required training of the service sector manageable.