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Executive Summary
Hydrofluorocarbons (HFCs) and to a lesser extent perfluorocarbons (PFCs) have
been introduced to replace ozone-depleting substances (ODSs) that are being
phased out under the Montreal Protocol on Substances that Deplete the Ozone
Layer. HFCs and PFCs have a significant global warming potential (GWP) and are
listed in the Kyoto Protocol. This Appendix estimates consumption and emissions
and assesses alternative practices and technologies to reduce emissions. Emissions
as by-products of manufacturing are treated in the main part of Chapter
3.
In the absence of the Montreal Protocol the use of chlorine- containing compounds
and especially CFCs would have expanded significantly. However, because of this
treaty, developed countries replaced about 8% of projected chlorofluorocarbon
use with HFCs, 12% with HCFCs, and eliminated the remaining 80% by controlling
emissions, specific use reductions, or by using alternative technologies and
fluids including ammonia, hydrocarbons, carbon dioxide, water, and not-in-kind
options.
In 1997, the production of HFCs was about 125 kilotons (50MtCeq),
and the production of PFCs amounted to 5 kilotons (12MtCeq). The
production of HFCs in 2010 is projected to be about 370 kilotons or 170MtCeq
and less than 12MtCeq for PFCs, assuming current trends in use and
regulations, substantial investment in new HFC production capacity, and success
of voluntary agreements. Since most of the HFCs and some of the PFCs are contained
in equipment or products, annual emissions lag production when use is growing.
Refrigeration, air conditioning, and heat pumps are the largest source of emissions
of HFCs. Improved design, tighter components, and recovery and recycling during
servicing and disposal can reduce lifetime HFC emissions at moderate to low
costs. Non-HFC alternatives include hydrocarbons, ammonia, and carbon dioxide,
or alternative technologies. Lifecycle climate performance (LCCP) analysis of
the entire system, including direct fluid emissions and indirect emissions from
carbon dioxide resulting from energy use by the device, provides a means of
assessing the net contribution of a system to global climate change. The LCCP
calculations are very system specific and can be used to make relative rankings.
However, since the LCCP approach involves regional climate conditions and local
energy sources, the results cannot be generalized in order to make globally
valid comparisons.
Insulating foams are anticipated to become the second largest source of HFC
emissions and HFC use is expected to grow rapidly as CFCs and HCFCs are replaced
with HFC-134a, HFC-245fa, and HFC-365mfc. Alternative blowing agents including
the different pentanes and carbon dioxide have lower direct climate impact from
direct emissions. However, they also have lower insulating values than CFCs
and HCFCs, and hence may have higher indirect emissions from energy use if the
foam thickness is not increased to offset the higher conductivity. Non-foam
insulation alternatives such as mineral fibres are also used, and vacuum panels
may play a role in the future.
Other sources of HFC and PFC emissions are industrial solvent applications,
medical aerosol products, other aerosol products, fire protection, and non-insulating
foams. A variety of options are available to reduce emissions including increased
containment, recovery, destruction, and substitution by non-fluorocarbon fluids
and not-in-kind technologies. There are no zero- or low-GWP alternatives for
some medical and fire protection applications.
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