United Nations Environment Programme
Ozone depleting substances, particularly HCFCS, and non-ozone depleting alternatives such as HFCs are the most commonly used substances in refrigeration and air-conditioning applications. Most HCFCs and HFCs used in these applications have global warming potentials (GWPs) that are in the range of 1000 to 4000 times more powerful as greenhouse gases than carbon dioxide. Some of the low GWP alternatives to HCFCs and HFCs have properties such as higher flammability, higher toxicity and higher pressure that require a significantly different approach than that employed for previous generations of refrigerant technologies, due to the related safety issues.
Designers of products and equipment need to seek lower GWP alternatives that provide the best performance over a number of criteria, including: energy efficiency, safe operation, competitive costs, good environmental performance (which in most cases is a combination of high energy efficiency, minimal leakage and a low or very low GWP refrigerant).
In most markets efficient and economically feasible technology options are available or close to market. However there is some concern of finding feasible alternatives for the air-conditioning industry in high ambient temperature countries, and this has been a topic of considerable interest to the Parties to the Montreal Protocol in recent years.
UN Environment OzonAction supports developing countries in making informed decisions regarding adoption of appropriate alternative technologies as part of the ODS phase-out strategies for developing countries, which will also be extended to the phase-down of HFCs in the coming years. This includes the implementation of the project “Promoting low GWP Refrigerants for Air-Conditioning Sectors in High-Ambient Temperature Countries” (PRAHA) in cooperation with UNIDO to assess the feasibility of low-GWP refrigerants suitable for air conditioning technology in high-ambient temperature countries.