TRANSITIONING TO LOW-GWP ALTERNATIVES 

IN COMMERCIAL REFRIGERATION

Background

This fact sheet1 provides current information on low-Global Warming Potential (GWP) alternatives in newly manufactured commercial 

refrigeration equipment relevant to the Montreal Protocol on Substances that Deplete the Ozone Layer.Commercial refrigeration includes 

refrigerated equipment found in supermarkets, convenience stores, restaurants, and other food service establishments. In 2006, there were 

an estimated 530,000 supermarkets worldwide, containing roughly 546,000 metric tons of refrigerant.

Due to their large charge sizes, the multiplex rack systems typically used in these supermarkets account for the greatest percentage (60%) 

of refrigerant installed in the commercial refrigeration sector. HCFCs account for the majority of refrigerant (55%). The figures below 

graphically present the distribution of the global commercial refrigerant stock by system and refrigerant type in 2006. Equipment in this 

end-use typically lasts approximately 15–20 years. Equipment can be broadly categorized as either self-contained or remote refrigeration 

systems, as explained further below.

Stand-Alone or Self-Contained Refrigeration Systems 

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 Integrate all refrigerating components within their structures 

 Low charge sizes (~0.15 kg)

 Most often contain HCFC-22, HFC-134a, or R-404A (a blend of HFCs)

 Estimated 32 million stand-alone units in use worldwide with an additional 

20.5 million vending machines

Remote Refrigeration Systems

Condensing Unit Systems

 • Consist of one or two compressors, one condenser, and one receiver 

assembled into the condensing unit system; linked to one or more display 

case(s) in the sales area through a piping network

Most often contain R-134a, R-22, or R-404A 

R-407C, R-507, other HFC blends, and HCFC blends are also used

Refrigerant charges vary in size from 0.5–20 kg

Approximately 34 million systems are in use worldwide

Multiplex Rack Systems

 • Remote refrigeration systems 

consisting of racks of multiple 

compressors contained typically in a 

machinery room; linked to multiple 

display cases in the sales area through 

extensive piping. Condensers are 

usually remotely located, such as on 

the roof above the machinery room.

Distribution of Global Commercial Refrigerant 

Stock by System and Refrigerant Type (2006)

Condensing

Unit Systems

33%

Multiplex Rack 

Systems

60%

Stand-Alone

Systems

7%

HCFCs

55%

CFCs

30%

HFCs

15%

2010 HFC Consumption

(Estimates Presented in MMTCO2eq.)

Refrigeration/

AC (79%)

Foams 

(11%)

Aerosols

(5%)

Fire Extinguishing

(4%)

Solvents

(1%)

Other 

Refrigeration/AC

(60%)

Commercial

Refrigeration

Developed

Countries

(25%)

Commercial

Refrigeration

Developing

Countries (15%)

Global HFC Consumption Total: 1,087 MMTCO2eq.

Global Refrigeration/AC Total: 858 MMTCO2eq.

Global HFC Consumption Commercial Refrigeration: 346 MMTCO2eq.
 • Various designs exist: direct (also called direct expansion) is most 

common and circulates refrigerant from a central machinery 

room to the sales area; indirect (also called secondary loop) 

systems chill an intermediate fluid, which is circulated from the 

refrigerant-containing equipment to the display cases.

R-22 is the most widely used refrigerant in multiplex rack systems

CFC-12, R-502, R-404A, R-507A, R-407A, and several HCFCand HFC-based blends designed for retrofit of existing CFC or 

HCFC installations are also used

Charge size ranges from 300–3,000 kg, depending on the size of 

the supermarket and on design (e.g., pipe layout and operating 

characteristics)

Currently, the commercial refrigeration sector accounts for 

approximately 32% of global HFC consumption, or 40% of HFC 

consumption in the refrigeration/AC sector. Developing countries 

account for an estimated 131 million metric tons of carbon dioxide 

equivalent (MMTCO2eq.) or 38% of the global HFC consumption in 

this end-use today.

Alternatives and Market Trends

Many design strategies exist today to reduce the amount of 

refrigerant needed while at the same time reducing the likelihood of 

leaks and mitigating risks if using a flammable or toxic refrigerant. 

Although most of these advanced refrigeration systems still rely on 

HFC refrigerants, they have great potential for drastically reducing 

HFC consumption in multiplex rack commercial refrigeration systems. 

In addition, a number of climate-friendly alternatives to CFC/HCFC/

HFC refrigerants are, or will become, available for use in commercial 

refrigeration applications. Alternatives available today include 

hydrocarbons—isobutane (R-600a), propane (R-290), and propylene 

(R-1270)—ammonia (R-717), and carbon dioxide (R-744). Other 

alternatives, such as new HFCs/HFOs, are also likely to enter the 

market in the coming years.

Advanced Refrigeration System Designs 

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Distributed systems2 and indirect systems3 have been available for 

more than 20 years

Distributed systems can lower refrigerant charge by 30–50% 

Indirect systems can lower refrigerant charge by 50–80% 

In the European Union, indirect systems are now the norm; 

in the United States, distributed systems account for 40% of 

new installations, and indirect systems are gaining significant 

market share

Refrigerant GWP ODPa

R-12 10,900 1

R-502 4,657 0.334

R-507A 3,985 0

R-404A 3,922 0

R-407A 2,107 0

R-22 1,810 0.055

R-407C 1,774 0

R-134a 1,430 0

R-32 675 0

R-290 (propane) 3.3 0

R-600a (isobutane) 3 0

R-1270 (propylene) 1.8 0

R-744 (CO2) 1 0

R-717 (ammonia) 0 0

aODP = ozone depletion potential

Australia’s Experience

Australia’s major supermarkets have committed to reducing 

commercial refrigeration emissions through lower GWP 

refrigerants, advanced refrigeration technology, and 

innovative store designs. The supermarket chains determined 

that half of their emissions are from refrigeration systems. 

Losses from HFC refrigerants account for a significant portion 

of these emissions. Supermarkets are incorporating CO2

cascade and transcritical refrigeration systems to meet their 

target reductions in CO2eq. emissions. Shifting from HFCs 

to CO2 can reduce the carbon footprint of supermarkets by 

25%. Since 2008, at least 23 stores have implemented this 

new technology. Australia has evaluated the benefits of new 

technologies and provided assistance to update supermarket 

refrigeration equipment.
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Refrigerant Transition in the Commercial Refrigeration End-Use*

R-12 R-404A R-12

R-22 R-22

R-744 R-404A R-404A

R-744

R-744

R-600a R-507A R-507A

R-717

R-290

R-717

R-290 R-407C R-407A

R-1270

HFO

Blends

R-1270

R-290

R-134a R-502 R-22

Stand-Alone Equipment Condensing Unit Systems Multiplex Rack Systems

*Solid arrows represent alternatives already available in the market for 

these systems; dashed arrows indicate those likely to be available in 

the future.

Distributed secondary loop,4 compact chiller,5 and cascade6 designs were 

introduced recently

Systems often use HFC refrigerants but can also use natural refrigerants 

(e.g., hydrocarbons, ammonia)

Hydrocarbons

Primarily used in many northern European countries including Denmark, 

Germany, Sweden, and the United Kingdom

R-290 and R-1270 are used in condensing unit systems produced in northern Europe, 

as well as in indirect multiplex rack systems as a primary refrigerant

A growing proportion of self-contained (stand-alone) equipment now uses propane (R-290) instead of R-134a

Several large-scale beverage companies have begun producing beverage dispensing fountains with isobutane (R-600a)

R-717

 Introduced as a primary refrigerant in indirect systems in northern European countries and Africa

R-744

Many companies producing larger vending machines use R-744 in lieu of R-134a (e.g., Sanyo)

Used as refrigerant in condensing unit systems and multiplex rack systems, mainly in Europe

Used as the heat transfer (i.e., secondary) fluid in indirect systems in some countries, such as the United States

Used in the low-temperature loop in cascade systems (often with small amounts of R-134a or R-717 in the high-temperature loop) 

HFO Blends

New refrigerant blends (e.g., with HFC-32 and/or HFOs) are being developed and may become available in multiplex rack refrigeration 

systems in the next few years

System Design Transition 

in Multiplex Rack Systems*

Distributed

Secondary Loop

Cascade

Compact

Chiller

Distributed

Secondary

Loop

Direct

Expansion
Challenges to Market Entry and Potential Solutions

Several challenges have limited the transition to climate-friendly alternatives in this end-use. The following table summarizes the challenges 

associated with the various alternatives as well as potential solutions to overcoming them.

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Alternative Challenges to Market Entry Potential Solutions

Advanced Refrigeration 

System Designs

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Technician and Operator Experience

Energy Efficiency Concerns

Training and Education

Standards and Service Procedures

Case Studies and Operational Guidelines

Hydrocarbons Highly Flammable

Safety Code Restrictions

Liability Concerns

Safety Devices

Standards and Service Procedures

Training and Education

R-717 Toxic and Slightly Flammable

Building and Fire Code Restrictions

Engineering Design

Standards and Safety Regulations

Revisions to Existing Codes

R-744 Safety Risks

High Operating Pressure

Engineering Design

Training and Education

HFO Blends Market Availability Research and Development

Future Outlook

Together, the suite of known alternative chemicals, new technologies, and better process and handling practices can significantly reduce 

HFC consumption in both the near and long term, while simultaneously completing the HCFC phaseout. Although there is much work to do 

to fully adopt these chemicals, technologies, and practices, and some unknowns still remain, the industries currently using HCFCs and HFCs 

have proven through the ODS phaseout that they can move quickly to protect the environment.
References

Center for Sustainable Production and Consumption (C-SPAC). 2005. “Ecofridge: Make the Right Choice Now.” Consumer Unity & Trust Society (CUTS).

Available online at: http://www.cuts-international.org/sc98-1.htm. Accessed August 19, 2010.

Frigrite. “Woolworths Control Temperature Case Supply Agreement Executed.” July 20, 2009. Available online at: 

http://media.wotnews.com.au/asxann/00969994.pdf. Accessed September 30, 2010.

GTZ-Proklima International. 2010. “Conversion of Supermarket Refrigeration Systems from F-Gases to Natural Refrigerants.” Funded by Federal 

Ministry for Environment, Natural Conservation, and Nuclear Energy.

International Panel on Climate Change (IPCC). 2007. “Climate Change 2007: The Physical Science Basis.” Contribution of Working Group I to the 

Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. 

Tignor, and H.L. Miller (Eds.). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. September 2007. Available online at: 

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/contents.html. Accessed September 30, 2010.

Kauffeld, Michael. 2008. “Trends and Perspectives in Supermarket Refrigeration.” Available online at: 

http://www.ammonia21.com/files/papers/trends-perspectives-supermarket-refrigeration.pdf. Accessed September 30, 2010.

Mahone, D. and Roberts, J. 2008. “White Paper on Approaches to Reducing Leakage and Improving the Performance of Supermarket Refrigeration 

Systems.” Prepared by Heschong Mahone Group, Inc. and CTG Energetics, Inc. for the California Energy Commission.

Palmer, Daniel. 2008. “Green supermarkets – the way of the future.” Australian Food News. June 5, 2008. Available online at: 

http://www.ausfoodnews.com.au/2008/06/05/green-supermarkets-the-way-of-the-future.html. Accessed September 30, 2010.

Technology and Economic Assessment Panel (TEAP). 2009. “Task Force Decision XX/8 Report, Assessment of 

Alternatives to HCFCs and HFCs and Update of the TEAP 2005 Supplement Report Data.” May 2009. Available online at: 

http://www.unep.ch/ozone/Assessment_Panels/TEAP/Reports/TEAP_Reports/teap-may-2009-decisionXX-8-task-force-report.pdf. Accessed September 

30, 2010.

U.S. Environmental Protection Agency (EPA). 2010. “Overview on Commercial Refrigerants: where are we headed?” Presented by Jeremy Arling, 

U.S. EPA; Dave Godwin, U.S. EPA; Ron Vogl, Honeywell; Stephen Speltzer, Arkema; Nick Strickland, DuPont; Scott Koerper, Mexichem Flour; and David 

Callendar, ICOR International; at the April GreenChill Webinar. April 29, 2010. Available online at: http://www.epa.gov/greenchill/events.html. Accessed 

September 30, 2010.

U.S. Environmental Protection Agency (EPA). 2006. “Global Mitigation of Non-CO2 Greenhouse Gases.” June 2006. Available online at: 

http://www.epa.gov/climatechange/economics/downloads/GlobalMitigationFullReport.pdf. Accessed September 30, 2010.

Woolworths Limited. 2008. “Environmental Sustainability.” Woolworths Limited Corporate Responsibility Report 2008. Available online at: 

http://crreport08.woolworthslimited.com.au/climate_change.php. Accessed September 27, 2010. 

1 The four fact sheets in this series (October 2010) cover domestic refrigeration, commercial refrigeration, motor vehicle air conditioning, and 

unitary air conditioning. These four end-uses represent about 85% of HFC consumption in the refrigeration/AC sector. The remaining HFC 

consumption in the refrigeration/AC sector comes from other end-uses including chillers, cold storage, industrial process refrigeration, and 

refrigerated transport. Any service-related consumption is attributed to the specific end-use.

2 Distributed systems use an array of separate compressor racks located near the refrigerated cases rather than having a central 

compressor system.

3 Indirect systems use a chiller to cool a secondary fluid that is then circulated throughout the store to the cases and coolers.

4 Distributed secondary systems combine secondary loops with the typical distributed design. 

5 Compact chiller versions of an indirect system rely on a lineup of 10–20 units, each using approximately 4–7 kg of refrigerant. 

6 Cascade systems use a compressor to raise the low-temperature coolant (often CO2) from low-temperature conditions up to an 

intermediate temperature while a separate refrigerating system uses a different refrigerant to condense the coolant.

U.S. Environmental Protection Agency

EPA-430-F-10-043 • www.epa.gov • October 2010

Printed on 100% recycled/recyclable paper with a minimum 

50% post-consumer waste using vegetable-based inks