The use of hydrofluorocarbons (HFCs) has recently been at the center of policy deliberations in the United States and globally. Many HFCs used in refrigeration have high global warming potential (GWP) and have become the target for reductions by the U.S. Environmental Protection Agency and the over 170 countries that are parties to the Montreal Protocol.

The U.S. Environmental Protection Agency (EPA) is continuing its efforts to restrict the use of HFCs through amendments to the Significant New Alternatives Policy Program (SNAP). On September 26, 2016, EPA published a Final Rule that changes the list of acceptable refrigerants for various uses, including industrial refrigeration.

The EPA action comes as a part of President Obama’s Climate Action Plan (CAP), which set the goal to reduce emissions of HFCs both through domestic policy changes and through multi-lateral agreements such as the Montreal Protocol. The CAP specifically identifies the SNAP program as a mechanism to encourage private sector investment in low-emissions technology by identifying and approving climate-friendly chemicals while prohibiting certain uses of the most harmful chemical alternatives.

Through the SNAP program, EPA lists substitute refrigerants as acceptable, acceptable subject to use conditions, acceptable subject to narrowed use limits, or unacceptable (prohibited) for specific uses. SNAP program rules require EPA to prohibit the use of a substitute where EPA has determined that there are other available or potentially available substitutes that pose less overall risk to human health and the environment.

As part of its evaluation of substitutes, EPA considers many criteria, including flammability or toxicity, as well as potential environmental risks such as global warming potential (GWP). This has led EPA to target the use of HFCs, many of which have high GWPs. As a natural refrigerant with no GWP, ammonia is qualified as an approved substitute.

The Final Rule published in September 2016 places restrictions on a number of HFCs currently used in industrial refrigeration. As of October 26, 2016, new cold storage warehouses will not be permitted to use Propylene (R-1270) or R-443A as refrigerants. By January 1, 2023, new cold storage warehouses and retail food refrigeration (refrigerated food processing and dispensing equipment) will not be permitted to use: HFC227ea, R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407A, R-407B, R-410A, R-410B, R-417A, R-421A, R-421B, R-422A, R-422B, R-422C, R-422D, R-423A, R-424A, R-428A, R-434A, R-438A, R-507A, and RS-44 (2003 composition). The inclusion of R-134a, R-404A and R-507A are of particular note, as these have been adopted by some industrial refrigeration facilities during the transition away from R-22. In addition to restricting HFC use, the SNAP Final Rule also made some additions. Most notably, EPA is listing propane as acceptable, subject to use conditions, as a refrigerant in new self-contained commercial ice machines, in new water coolers, and in new very low temperature refrigeration equipment. EPA is also exempting propane in these enduses from the venting prohibition under Clean Air Act (CAA). The CAA allows EPA to exempt specific refrigerants from the venting prohibition where EPA finds that it does not pose a threat to the environment.

While the EPA has been making unilateral changes to the United States HFC policies, the parties to the Montreal Protocol have been working to advance a multilateral agreement to curb global HFC use. The Montreal Protocol, which has been signed by over 170 countries across the globe, has been successful in addressing ozone depleting substances such as the refrigerant R-22. However, the inclusion of HFCs in the Montreal Protocol to address global warming has been the subject of heated debate for several years. Developing countries including India and China had expressed concerns about transitioning away from HFCs too quickly for their respective economies to adjust.

There was a breakthrough in late 2015, when an agreement was reached in Paris to develop a pathway for addressing HFCs during 2016. The Paris Agreement established the goal to keep global warming below 2 degrees celsius, compared with pre-industrial levels. An important component of meeting this goal is the global reduction in HFC use. According to a 2015 study by the Institute for Governance and Sustainable Development, the elimination of HFCs could reduce global warming by 0.5 degrees by 2100.

The Paris Agreement led to a series of meetings in 2016 that culminated with a summit in Kigali, Rwanda in October 2016. Participants in the Kigali meetings agreed to a framework that would begin a global phase down of HFC use.

Below is a summary of the dates and targeted rates of reduction in HFC use:

Developed countries, including the United States, Japan and European Union (EU), must reduce their use of HFCs by 10 percent by 2019 from 2011- 2013 levels. By 2036, HFC use must be reduced by 85 percent. (It is worth noting that the EU established its own policies and targets for the reduction of HFC use in 2015.) Developing countries would be separated into two groups. The first group, including China and African nations, must begin their transition away from HFCs in 2024. By 2029, these countries must reduce HFC by 10 percent compared with 2020-2022 levels. HFC use would be reduced by 80 percent by 2045.

The second group of developing countries, including India, Pakistan, Iran, Iraq and Arab Gulf states, must begin the transition in 2028 with a 10 percent reduction required by 2032, based on 2024-2026 levels. This group of countries would need to achieve an 85 percent reduction in HFC use by 2047.

The recent policy changes by the EPA to further restrict the usage of HFCs and the signing of the Kigali Agreement signal important opportunities for the increased adoption of natural refrigerants. As the phase down of HFCs continues in the United States and abroad, the interest in natural refrigerants including ammonia and CO2 will continue to grow and the development of new technologies for lower charge and package systems will give companies even more options as they transition away from HFCs.