Maybe they’re serious this time.
Since at least 2009, the international refrigeration community has been discussing a global phasedown of hydrofluorocarbons (HFCs). Today, it’s gaining greater attention, because, even though the transition from chlorofluorocarbons (CFCs) to hydrochlorofluorocarbons (HCFCs) and then to HFCs has resulted in gases with lower climate change impacts, the growing use of air conditioning and refrigeration around the world has resulted in more refrigerant use and the need to use even lower-GWP (global warming potential) refrigerants.
It’s looking more likely that there will be a global agreement to phase down HFCs, and it could come as early as this year or possibly next; either way, it’s coming. A phasedown won’t have an immediate effect on all HVACR products, but proposals from several countries and regions suggest there will be a significant decrease in the use of high-GWP gases for many applications in about 10 years, and another reduction around 15 years from now.
Not waiting for a global agreement, the U.S. is already moving in that direction. The U.S. Environmental Protection Agency (EPA), through its Significant New Alternatives Policy (SNAP) program, has announced the phaseout of some high-GWP refrigerants for supermarkets, stand-alone refrigeration units, and vending machines. The ban on usage of those high-GWP refrigerants will begin as early as July 1, 2016, for refrigerant retrofits into existing equipment, through Jan. 1, 2020, for some new stand-alone equipment. Motor vehicle air conditioning is also affected, as R-134a will no longer be allowed beginning in the 2021 model year.
Europe put into force its F-gas regulation at the beginning of 2015. The regulation contains specific dates for sectorial refrigerant phaseout. There may be some important lessons learned and global implications from Europe’s actions. In a region where there is much more need for refrigeration than air conditioning, Europe is focusing on low-GWP solutions for supermarkets and other refrigeration applications — beginning with phasing out R-134a in autos, domestic refrigerators, and freezers. Today, more than 90 percent of European refrigerators use isobutane as a refrigerant, and their safety records have been excellent. Europe will look to first ban high-GWP refrigerants in new equipment, followed by service bans in future years.
AMERICA’S FUTURE LANDSCAPE
We all know there’s no magic bullet or single replacement refrigerant. The refrigerants of the future will vary by application, and it’s important to take into consideration the life cycle climate performance of each.
Supermarkets are the first target of the HFC phasedown for several reasons. Supermarkets have large charges of the highest-GWP refrigerants, and they have a history of relatively high leakage rates, making them visible targets. We’re likely to see movement to lower-GWP HFCs as well as hydrofluoroolefins (HFOs) and, eventually, a transition to natural refrigerants, including carbon dioxide (CO2) and propane, in very small refrigerant loops. We may see ammonia chillers with a heat-transfer loop to cool display cases.
In particular, transcritical CO2 systems have recently garnered increased interest in an attempt to become the standard natural refrigerant solution for supermarkets in the U.S. While low GWP and high cooling capacity are features that have always made CO2 a preferred refrigerant, the industry’s recent ability to better understand and support the technological requirements associated with this type of system have led to a strong increase in installations over the past few years. This, in turn, has led to overall cost decreases, bringing a transcritical system much more in line with a standard system and also making it more appealing to the market. In addition, new technology improvements will negate previous hurdles that prevented the technology from being applied to all regions of the U.S.
Smaller refrigeration display cases have already begun to be produced in Europe with small charges of propane as a refrigerant, and we expect to see them in North America, as codes allow. Until then, low-GWP HFOs and CO2 are likely to be good candidate refrigerants.
For air conditioning and heat pump applications, look for the changes to start in smaller equipment and then move up to larger types. In April, the EPA listed R-32 as a suitable alternative for room air conditioners. For larger equipment, such as central unitary air conditioning and heat pumps, testing continues. The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) is coordinating the Low-GWP Alternative Refrigerants Evaluation Program (AREP), in which organizations are testing and reporting on the performance of a variety of blends that have been finely tuned for those applications. The jury is still out on them.
Still, the risks are many. One is meeting energy-efficiency requirements while, at the same time, considering new refrigerants. All the equipment potentially impacted by a phaseout also must meet minimum efficiency standards set forth by the Department of Energy (DOE) or ASHRAE Standard 90.1. Keep in mind we don’t yet know what the efficiency targets will be for some of these applications in the timeframe of these refrigerant phasedowns. Conversely, some of the current efficiency rulemakings do not consider that alternative refrigerants may become mandatory for certain equipment.
A WORD ABOUT CODES
Currently, the major model building codes that the states look to adopt as their own do not allow the use of mildly flammable A2L refrigerants and have severe restrictions on flammable A3 refrigerants. While Danfoss is coordinating an industry taskforce with the goal of facilitating the code process, much work remains to be done.
In fact, while we can reasonably speculate what tomorrow’s refrigerants might be, there remains a lot of designing, performance testing, safety approval, and training required before any of these changes can take place. The EPA will have to consider this in phasing down or phasing out any gases. Finally, the DOE and EPA need to work much more closely than they have in the past if we are to have a comprehensive, workable plan for reducing global warming gas emissions.
Publication date: 8/31/2015