04-10-2014, 03:40 PM
Refrigeration and Air Conditioning with Reduced
Environmental Impact
Refrigeration.pdf (Size: 594.24 KB / Downloads: 69)
ABSTRACT
Manufacturers of refrigerants and refrigeration and air conditioning equipment, governmental
agencies, and environmental groups continue working together toward the goal of reduced environmental
impact via reduced emissions and improved energy efficiency. Examples of progress are presented for
several sectors of refrigeration and air conditioning, followed by projections for further significant
reductions.
Working fluid selection for the myriad of refrigeration and air conditioning applications is based
on three factors: safety (toxicity and flammability), environmental impact (stratospheric ozone and
climate change), and performance (cooling and heating with required capacity, energy efficiency,
reliability, and cost effectiveness). Although this paper will emphasize environmental impact for fluid
selection, all of the factors must be evaluated to determine the most appropriate fluid for each application.
ENERGY EFFICIENCY AND EMISSIONS
Unlike the situation with stratospheric ozone depletion in which chlorine containing compounds
are being phased out to protect the ozone layer, climate change discussions are appropriately focused on
emissions. The Kyoto Protocol is based on a "basket of gases" so no single class of gases must be
targeted for phase out. HFC compounds have a range of global warming potential values and are included
in the basket. For the high societal value refrigeration and air conditioning applications, 1-IFCs are prime
candidates for reducing net emissions within the basket of gases. Very specifically, at equivalent costs of
other options, climate change impact from minimal refrigerant emissions can be more than offset by
improved energy efficiency (thereby reducing C02 emissions), while meeting reliability and safety
requirements. As one example, with a typical North American split system heat pump having a 5%
annualized refrigerant loss, the refrigerant climate change impact can be offset by a 5% increase in energy
efficiency. This well-known approach has been described in many publications (examples being 1,2).
The following sections describe a progression of energy efficiency improvements and refrigerant
emission reductions, demonstrating industry capability and commitment to produce and operate
refrigeration and air conditioning systems with a continuing reduction in environmental impact.
REDUCED REFRIGERANT EMISSIONS
Emphasis in this section will be directed to refrigerant emissions from auto air conditioning and
supermarket refrigeration systems, as they have had the highest amounts of leakage; however, low
emission rates from other systems are briefly described. The projected long term reductions in emission
rates for all the applications are based on industry commitment to low emission goals through equipment
design, operating and maintenance procedures, refrigerant recovery, and appropriate governmental
regulations.
CONCLUSIONS
1. Industry, environmental groups, and governmental agencies have cooperated over the last two
decades to bring about dramatic reductions in refrigeration and air conditioning systems energy
consumption and refrigerant emissions. The reductions have been possible through a combination of
factors: increased environmental impact awareness, commitment of industry personnel, improved
systems technology and operating/service procedures, and governmental regulations.
2. These successes give us great confidence in continuing efforts for reduction of climate change impact
of refrigeration and air conditioning system.
3. HFC refrigerants have high societal value in providing safe and reliable refrigeration and air
conditioning. At equivalent costs of other options, climate change impact from minimal refrigerant
emissions can be more than offset by improved energy efficiency