Commercial air conditioning is essential for contemporary societal comfort in most of the world. These systems contribute to health and comfort, worker productivity and economic vitality. Commercial air conditioning is used in stores, restaurants, offices, hotels, hospitals, and other public places.

Commercial air conditioning is used in modern airports, hospitals, and other commercial facilities.

Since the mid-1980s, commercial air conditioning systems have undergone a transition from using ozone depleting compounds, including chlorofluorocarbons (CFCs), to low and no-ozone depleting compounds, such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). Ammonia and absorption are also being used, to a lesser extent.

Because of their excellent refrigerant properties and low chemical reactivity, CFCs were initially used in large chillers. HCFCs were used in smaller room and roof-top air conditioners. Today, blends including R-407C and R-410A have been introduced to replace HCFC-22 in small machines, and hydrocarbons are used in some new equipment. Chillers can use HCFC-123, HFC-134a, HFC-410A, HCFC-22 and ammonia. Long term, HCFCs will phase out under the Montreal Protocol. Absorption can also be used, which employs different technology. All new equipment today is essentially sealed; the high containment integrity minimizes refrigerant loss.

Replacement of CFC air conditioning systems worldwide with new, high efficiency chillers is saving billions of kilowatt hours annually, and corresponding millions of tons of electricity derived CO2.¹

Many office facilities use roof mounted air conditioning units.

Life-Cycle Climate Performance is expressed as kilograms of CO2. This includes both the greenhouse gas emissions ("direct effect") and the energy consumed ("indirect effect"). Air conditioning system operation is energy intensive which dominates the LCCP. However, minimizing system leakage and refrigerant loss during installation, commissioning, servicing, decommissioning at the end of life, and ultimate equipment disposal are also important. Other considerations include system cost and user safety including service technicians and the public.

AD Little calculated LCCP Performance for systems and air conditioning fluids (Reference #2). Four major points are highlighted: [1] The indirect effect from energy consumed accounts for over 96% of LCCP; [2] With a constant system Seasonal Energy Efficiency Ratio (SEER), differences between various Fluorocarbon (FC) refrigerants are small; and [3] Propane shows minimally less LCCP at the same SEER but, [4]This slight hydrocarbon refrigerant advantage is lost when a secondary loop is added for flammability safety.

In many hot climates, air conditioning is essential to business.

Commercial chillers represent a similar analysis. LCCPs for HCFC-123, HFC-134a, HCFC-22 centrifugal chillers range from 8.1M to 9.2M kg CO2. LCCPs for HCFC-22, HFC-134a and HFC-410A screw chillers range from 8.3M Kg to 8.7M Kg CO2. Ammonia is less efficient than the fluorochemical chillers (9.1M kg CO2). Absorption technology, which uses heat rather than mechanical energy to produce cooling has no direct effect but has the largest LCCP of 15.3M kg CO2 when powered by primary fuel.

After HCFCs are no longer available, HFCs, widely used in equipment today, will become the refrigerants of choice for air conditioning applications ranging from small room air conditioners to large chillers. Commercially available throughout the world, HFCs are energy efficient, low in toxicity, cost-effective, can be used safely and are reusable.

The air conditioning industry is committed to responsible use and management of all refrigerants including HCFCs and HFCs. The industry actively promotes the following principles:

• Contain refrigerants in tight systems and containers minimizing atmospheric releases;
• Recover, recycle and reclaim refrigerants;
• Train all personnel in proper refrigerant handling;
• Comply with applicable standards (e.g., ASHRAE-15, and ISO 5149) on refrigerant safety;
• Comply with all relevant Ozone Depletion Regulation provisions (Section 608, US Clean Air Act);
• Size equipment to match the specific need, thereby minimizing the refrigerant amount; and
• Design, install and operate to optimize energy efficiency.

The Alliance for Responsible Atmospheric Policy is a leading industry voice which coordinates industry participation in the development of reasonable international and U.S. government policies regarding ozone protection and global climate change.

¹Air-Conditioning & Refrigeration Institute, March 29, 2000 Press Release

²Comparison of HFC and Alternative Technologies for Refrigeration, Air Conditioning, Foam, Solvent, Aerosol Propellant, and Fire Protection Applications; AD Little; August 1999.

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