Between the 1990s and 2010s, society became much more aware of environmental issues, including the ozone layer and climate change. The leakage of refrigerants has been found to contribute to ozone layer damage and unhealthy HFC levels. Because of such issues, there has been a greater drive to develop more environmentally friendly refrigerant options and find new ways to minimize refrigerant leakage.
Regulation and HFC Levels
Keep in mind that HFCs, which comprises the vast majority of modern refrigerants, are considered harmful greenhouse gases. In October 2016, the Montreal Protocol supported a global reduction in HFCs.
The EPA made plans to phase out HFCs beginning with household refrigerators and freezers and retail food refrigeration by 2021, cold storage warehouses by 2023, and both positive displacement and centrifugal chillers by 2024.
This move was met with resistance and ended up before the U.S. Court of Appeals where it was, in essence, shot down. However, the refrigeration industry knew that changes were going to have to be made and started planning for the inevitable, with California leading the charge with a much more aggressive approach to HFC reduction than even the EPA.
Why Refrigerants Are an Issue
Many of the more popular refrigerants have a high ozone depleting potential. One of the measures of the impact that refrigerants can have on the environment is the Global Warming Potential (GWP). It serves as a measure of the potency of a greenhouse gas compared to carbon dioxide and is based on direct emissions. HFC refrigerants have values in the thousands, while many HFOs have single-digit values.
In the past, the refrigerants used were CFCs, and included the likes of R-12 and R-113. The next shift was to HCFCs and HFCs such as R-22 and R134a. The need for HFC reductions is driving a new generation of refrigerants such as R1234ze. These new refrigerants are primarily HFOs and blends with much smaller GWP.
Design Challenges for HVAC Engineers
Just because a refrigerant has a smaller GWP does not mean that that its overall impact is better. If a refrigerant is not efficient, then indirect emissions can be extremely large. In addition, there is the problem of leaks and the impact that leaks can have on the environment. Newer refrigerants may not always be compatible with older elastomeric and polymer seals, causing compatibility issues and the potential for more leaks.
This leads to three new issues that the HVAC and refrigeration industries face as traditional refrigerants are phased out starting in 2019:
- Chemical compatibility with seals
- Reducing leaks
Seal Solutions for New Refrigerants
There are seal materials that are not only compatible with the most aggressive refrigerants on the market, but are proven to be effective at reducing leaks while contributing to the overall efficiency of the system. This will be the topic of our next blog post! Join us again to discover the seals and materials that provide this comprehensive solution.