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Global Warming Potentials of ODS Substitutes
The global warming potential (GWP) represents how much a given mass of a chemical contributes to global warming over a given time period compared to the same mass of carbon dioxide. Carbon dioxide's GWP is defined as 1.0.
- Why are there three values given for the GWP and atmospheric lifetime?
-
All GWP values represent global warming potential over a 100-year time horizon. Dashes indicate that the source did not include a GWP value for the given compound. The first value in each of the second and third columns is from Table 1-6 of the Scientific Assessment of Ozone Depletion, 2002. The second and third values in each of these columns are from the Intergovernmental Panel on Climate Change (IPCC
)
Second Assessment Report: Climate Change
1995 and the
IPCC Third Assessment Report: Climate Change
2001, respectively.
For more specific information on how many of these chemicals are used as substitutes for ozone-depleting substances, please visit the SNAP Program's web site.
The HFCs are numbered according to the ASHRAE Standard 34 scheme. None of the chemicals listed below depletes the ozone layer. GWP values for ozone-depleting substances are available in another table.
HFCs and PFCs
| Chemical | Atmospheric
Lifetime (years) |
GWP | Use |
|---|---|---|---|
| HFC-23
(CHF3) |
270
264 260 |
12,240
11,700 12,000 |
Byproduct of HCFC-22 used in very-low temperature refrigeration blend and component in fire suppression. Also used for plasma etching and cleaning in semiconductor production. |
| HFC-32
(CH2F2) |
4.9
5.6 5.0 |
543
650 550 |
Blend component of numerous
refrigerants.
|
| HFC-41
(CH3F) |
2.4
3.7 2.6 |
90
150 97 |
Not in use today.
|
| HFC-43-10mee
(C5H2F10) |
15.9
17.1 15 |
1,610
1,300 1,500 |
Cleaning solvent
|
| HFC-125
(C2HF5) |
29
32.6 29 |
3,450
2,800 3,400 |
Blend component of numerous
refrigerants and a fire suppressant.
|
| HFC-134
(C2H2F4) |
9.6
10.6 9.6 |
1,090
1,000 1,100 |
Not in use today.
|
| HFC-134a
(CH2FCF3) |
14
14.6 13.8 |
1,320
1,300 1,300 |
One of the most widely used
refrigerant blends, component of other refrigerants,
foam blowing agent, fire suppressant and propellant
in metered-dose inhalers and aerosols.
|
| HFC-143
(C2H3F3) |
3.5
3.8 3.4 |
347
300 330 |
Not in use today.
|
| HFC-143a
(C2H3F3) |
52
48.3 52 |
4,400
3,800 4,300 |
Blend component of several
refrigerant blends. |
| HFC-152a
(C2H4F2) |
1.4
1.5 1.4 |
122
140 120 |
Blend component of several
refrigerant blends and foam blowing agent. Also used
as an aerosol propellant.
|
| HFC-227ea
(C3HF7) |
34.2
36.5 33.0 |
3,660
2,900 3,500 |
Fire suppressant and propellant
for metered-dose inhalers, and refrigerant.
|
| HFC-236fa
(C3H2F6) |
240
209 220 |
9,650
6,300 9,400 |
Refrigerant and fire
suppressant.
|
| HFC-236ea
(C3H2F6) |
10.7
-- 10.0 |
1,350
-- 1,200 |
Not in use today.
|
| HFC-245ca
(C3H3F5) |
6.2
6.6 5.9 |
682
560 640 |
Not in use today; possible
refrigerant in the future.
|
| HFC-245fa
(C3H3F5) |
7.6
-- 7.2 |
1,020
-- 950 |
Foam blowing agent and
possible refrigerant in the future. |
| HFC-365mfc
(C4H5F5) |
8.6
-- 9.9 |
782
-- 950 |
Some use as a foam blowing
agent; possible refrigerant in the future. |
| Perfluoromethane
(CF4) |
50,000
50,000 50,000 |
5,820
6,500 5,700 |
Plasma etching and cleaning in
semiconductor production and low temperature
refrigerant.
|
| Perfluoroethane
(C2F6) |
10,000
10,000 10,000 |
12,010
9,200 11,900 |
Plasma etching and cleaning in
semiconductor production.
|
| Perfluoropropane
(C3F8) |
2,600
2,600 2,600 |
8,690
7,000 8,600 |
Plasma etching and cleaning in
semiconductor production, low temperature refrigerant
and fire suppressant.
|
| Perfluorobutane
(C4F10) |
2,600
2,600 2,600 |
8,710
7,000 8,600 |
Fire suppressant and
refrigerant where no other alternatives are
technically feasible.
|
| Perfluorocyclobutane
(C4F8) |
3,200
3,200 3,200 |
10,090
8,700 10,000 |
Not used much if any.
Refrigerant where no other alternatives are
technically feasible.
|
| Perfluoropentane
(C5F12) |
4,100
4,100 4,100 |
9,010
7,500 8,900 |
Not used much if any. Precision
cleaning solvent-low use refrigerant where no other
alternatives are technically feasible.
|
| Perfluorohexane
(C6F14) |
3,200
3,200 3,200 |
9,140
7,400 9,000 |
Precision cleaning solvent-low
use, refrigerant and fire suppressant where no other
alternatives are technically feasible.
|
NF3
| Chemical |
Atmospheric
Lifetime (years) |
GWP | Use |
|---|---|---|---|
| NF3 | 740
-- -- |
10,970
-- -- |
Plasma etching and cleaning in semiconductor production. |
SF6
| Chemical |
Atmospheric
Lifetime (years) |
GWP | Use |
|---|---|---|---|
| Sulfur hexafluoride
(SF6) |
3,200
3,200 3,200 |
22,450
23,900 22,200 |
Cover gas in magnesium production, casting dielectric gas and insulator in electric power equipment fire suppression. Also used as a discharge agent in military systems and formerly an aerosol propellant. |
HFEs
| Chemical |
Atmospheric
Lifetime (years) |
GWP | Use |
|---|---|---|---|
| HFE-7100
(C4F9OCH3) |
5.0
-- 5.0 |
397
-- 390 |
Cleaning solvent and heat
transfer fluid.
|
| HFE-7200
(C4F9OC2H5) |
0.77
-- 0.77 |
56
-- 55 |
Cleaning solvent and heat
transfer fluid.
|