A3.2 Refrigeration, Air Conditioning, and Heat Pumps
Most current and projected HFC consumption and emissions is in this sector.
HFC consumption in refrigeration and mobile and stationary air conditioning
in 1997 was, on a mass basis, about 30% of projected developed country CFC consumption
in the absence of the Montreal Protocol (McFarland, 1999). Most of the remaining
70% of projected consumption has been eliminated by reducing leaks, reduced
charge per application, and improved service practices; the substitution by
other fluids and new technologies played a lesser role (some substitution
a few per cent by HCFCs also took place). Globally, there is still a
huge potential to further reduce HFC emissions. Estimated consumption and emissions
of HFCs for this sector for 2000 and 2010 are shown in Table
A3.2. Emissions significantly lag consumption because HFC systems are relatively
new so emissions will occur well after 2010.
Table A3.2: Estimated and projected global HFC consumption
and emission for different sub-sectors for 2000 and 2010 |
|
Sub-sector |
2000
|
2010
|
|
|
HFC
consumption
|
HFC
consumption
|
HFC
emission
|
HFC
emission
|
HFC
consumption
|
HFC
consumption
|
HFC
emission
|
HFC
emission
|
|
|
kt/yr
|
MtCeq/yr
|
kt/yr
|
MtCeq/yr
|
kt/yr
|
MtCeq/yr
|
kt/yr
|
MtCeq/yr
|
|
Refrigeration & A/Ca,b
Mobile A/Cc
Domestic refrigerationf
Comm. refrigerationd, e, f
Cold storaged
Industrial refrigerationd
Chiller A/C
Transport refrigerationd, e, f
Unitary air conditioning |
102-112
64-74
7
19
4.5
1.5
2.5
3.3
-
|
47-50
23-26
2.5
15
3
1
1
1
-
|
40-44
31-35
0.9
5
1.2
0.3
0.2
1.3
-
|
18-19
11-12
0.3
4.5
0.8
0.2
0.1
0.7
-
|
195-255
58-79
15-17
46.5-64
9-12
3-4
3.5-4.5
17-23.5
43-51
|
106-139
21-28
5.5-6.4
39-54
6-8
2-2.7
2.3-3
8.5-12
22-25
|
82-124
37-54
3.5-4.5
19.5-31
3-4
0.6-0.8
0.5-0.7
10-14.5
8-14
|
42-64
13-19
1.3-1.7
16-26
2-2.5
0.4-0.5
0.3-0.5
5-7
4-7
|
|
|
|
|
|
|
|
|
|
Insulating foamsg
Solvents/ cleaningh
Med. aerosolh
Other aerosolh
Fire protectiona,b,i |
4+
<2
1
<15
1.0 - 1.6
0.6 - 0.9
|
1.5+
<9
<1
<4
0.8 - 1.3
0.5 - 0.8
|
<1
<2
1
<15
0.2-0.4
|
<0.5
<9
<1
<4
0.2 - 0.3
|
115
>2
<9
<20
1.6 - 2.0
|
29.5
<9
<4
<5
1.3 - 1.7
|
20-40
>2
<9
<20
|
5-10
<9
<4
<5
|
|
|
|
|
|
|
|
|
|
TOTAL |
125-136
|
63-66
|
59-62
|
32-33
|
343-403
|
155-189
|
134-196
|
66-93
|
|
The primary options for limiting HFC emissions are the use of alternative refrigerants
and technologies, reduced refrigerant charge, improved containment, recovery
with recycling, and/or destruction. There are no globally representative estimates
of the cost effectiveness of improved containment and recovery. In developed
countries, recovery during servicing of small domestic refrigerators captures
a relatively insignificant proportion of HFCs, while end-of-life recovery is
significant. For medium-sized devices such as commercial units with substantial
leakage rates, recovery during both multiple servicing and at the end of useful
life is both significant. For very large units recovery both during servicing
and at end of life is frequently done already because of the high economic value
associated with the large quantities of recovered fluids.
In developing countries, where low cost is important, the quality of equipment
is often poor, resulting in high failure rates. Since the service sector in
developing countries is normally not equipped with the tools for recycling,
the emissions of refrigerants during servicing and product disposal form a significant
portion of the overall emissions.
Recovery at theend of equipment life is likely to exhibit a poor cost-effectiveness
for smaller units. For these units, the introduction of economic incentives
will be necessary, probably together with voluntary agreements and/or government
regulations (as already exist in some countries) to achieve significant reductions
in this sector.
Carbon dioxide emissions associated with energy consumption by refrigeration,
air conditioning, and heat pump equipment are usually the largest contributions
to global warming associated with cooling equipment (AFEAS, 1991; Papasavva
and Moomaw, 1998). Japanese manufacturers estimate that energy-related CO2
emissions represent an even larger fraction of lifetime emissions for their
low leakage rate, small charge appliances. Thus, improvements in equipment energy
efficiency are often a cost-effective way to reduce greenhouse gas emissions
and to lower costs to consumers (March, 1998). Proper equipment design, component
performance, and the selection of the most appropriate refrigerant fluid are
the most important factors contributing to energy efficiency. Examination of
the LCCP of the system will determine which combination of operating efficiency
and fluid choice yields the lowest overall contribution to global warming.
Hydrocarbons, carbon dioxide, and to a lesser extent, ammonia are the most
likely alternatives to HFC refrigerants. No ammonia vapour compression units
have capacity less than 50kW. Since both hydrocarbons and ammonia are flammable
and ammonia is toxic, their acceptance will depend on cultural norms and specific
regulations in each country. Hydrocarbons are currently being used in about
50% of the refrigerators manufactured in Europe and in some manufactured in
Asia and Latin America; their use in these products as well as in other refrigeration
and air conditioning systems could increase. Large charges can present a safety
concern, and globally standardized mechanical and electrical safety standards
are being established.
If safety is a concern, secondary loops containing a heat transfer fluid can
be used. For modest cooling, such as water chilling for residential air conditioning
or industrial process chilling, there is no energy penalty from using a secondary
loop. For medium temperature applications in food processing and commercial
refrigeration, secondary loops permit the safe use of ammonia and hydrocarbons,
or enable minimization of an HFC refrigerant charge, generally with a modest
energy penalty. If safety concerns require a secondary loop for low temperature
applications in food processing and cold storage, in which normally the refrigerant
is used as the direct heat transfer fluid, a substantial energy penalty may
ensue.
Where they are required, the estimated cost of utilizing secondary loops with
ammonia and hydrocarbons to replace HFCs is estimated to exceed US$100/tCeq
(Harnisch and Hendriks, 2000). Secondary loop systems designed to achieve comparable
efficiency and demonstrated in Europe have up to a 15% higher cost.
An optimal transition strategy from ODSs to alternatives can substantially
lower costs and better meet development goals for developing countries, especially
in the refrigeration and air conditioning sectors (Papasavva and Moomaw, 1997).
The Montreal Protocol Multilateral Fund (MLF) and the Global Environment Facility
(GEF) have just begun to coordinate financing of ozone and climate protection
(IPCC/TEAP, 1999). To date, one project has been jointly funded by the MLF and
the GEF, which addresses energy efficiency in the replacement of CFCs. Energy
use forms a major problem for the stressed energy supply system of capital-strapped
developing countries. Since the greatest growth in refrigeration and air conditioning
is projected to occur in developing countries, it is important that they select
the most effective (in terms of costs and energy efficiency) non-ODS technology.
Currently, customers in developing countries make purchase decisions based on
initial cost with little consideration of energy consumption.
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