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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, respecively.
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 |
GWP | Use |
|---|---|---|---|
| HFC-23
(CHF 3) |
270
264 260 |
12240
11700 12000 |
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
(CH 2F 2) |
4.9
5.6 5.0 |
543
650 550 |
Blend component of numerous
refrigerants.
|
| HFC-41
(CH 3F) |
2.4
3.7 2.6 |
90
150 97 |
Not in use today.
|
| HFC-43-10mee
(C 5H 2F 10) |
15.9
17.1 15 |
1610
1300 1500 |
Cleaning solvent
|
| HFC-125
(C 2HF 5) |
29
32.6 29 |
3450
2800 3400 |
Blend component of numerous
refrigerants and a fire suppressant.
|
| HFC-134
(C 2H 2F 4) |
9.6
10.6 9.6 |
1090
1000 1100 |
Not in use today.
|
| HFC-134a
(CH 2FCF 3) |
14
14.6 13.8 |
1320
1300 1300 |
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
(C 2H 3F 3) |
3.5
3.8 3.4 |
347
300 330 |
Not in use today.
|
| HFC-143a
(C 2H 3F 3) |
52
48.3 52 |
4400
3800 4300 |
Blend component of several
refrigerant blends. |
| HFC-152a
(C 2H 4F 2) |
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
(C 3HF 7) |
34.2
36.5 33.0 |
3660
2900 3500 |
Fire suppressant and propellant
for metered-dose inhalers, and refrigerant.
|
| HFC-236fa
(C 3H 2F 6) |
240
209 220 |
9650
6300 9400 |
Refrigerant and fire
suppressant.
|
| HFC-236ea
(C 3H 2F 6) |
10.7
-- 10.0 |
1350
-- 1200 |
Not in use today.
|
| HFC-245ca
(C 3H 3F 5) |
6.2
6.6 5.9 |
682
560 640 |
Not in use today; possible
refrigerant in the future.
|
| HFC-245fa
(C 3H 3F 5) |
7.6
-- 7.2 |
1020
-- 950 |
Foam blowing agent and
possible refrigerant in the future. |
| HFC-365mfc
(C 4H 5F 5) |
8.6
-- 9.9 |
782
-- 950 |
Some use as a foam blowing
agent; possible refrigerant in the future. |
| Perfluoromethane
(CF 4) |
50000
50000 50000 |
5820
6500 5700 |
Plasma etching and cleaning in
semiconductor production and low temperature
refrigerant.
|
| Perfluoroethane
(C 2F 6) |
10000
10000 10000 |
12010
9200 11900 |
Plasma etching and cleaning in
semiconductor production.
|
| Perfluoropropane
(C 3F 8) |
2600
2600 2600 |
8690
7000 8600 |
Plasma etching and cleaning in
semiconductor production, low temperature refrigerant
and fire suppressant.
|
| Perfluorobutane
(C 4F 10) |
2600
2600 2600 |
8710
7000 8600 |
Fire suppressant and
refrigerant where no other alternatives are
technically feasible.
|
| Perfluorocyclobutane
(c-C 4F 8) |
3200
3200 3200 |
10090
8700 10000 |
Not used much if any.
Refrigerant where no other alternatives are
technically feasible.
|
| Perfluoropentane
(C 5F 12) |
4100
4100 4100 |
9010
7500 8900 |
Not used much if any. Precision
cleaning solvent-low use refrigerant where no other
alternatives are technially feasible.
|
| Perfluorohexane
(C 6F 14) |
3200
3200 3200 |
9140
7400 9000 |
Precision cleaning solvent-low
use, refrigerant and fire suppressant where no other
alternatives are technially feasible.
|
NF3
| Chemical |
Atmospheric
Lifetime |
GWP | Use |
|---|---|---|---|
| NF 3 | 740
-- -- |
10970
-- -- |
Plasma etching and cleaning in semiconductor production. |
SF6
| Chemical |
Atmospheric
Lifetime |
GWP | Use |
|---|---|---|---|
| Sulfur hexafluoride
(SF 6) |
3200
3200 3200 |
22450
23900 22200 |
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 | Life-time | GWP | Use |
|---|---|---|---|
| HFE-7100
(C 4F 9OCH 3) |
5.0
-- 5.0 |
397
-- 390 |
Cleaning solvent and heat
transfer fluid.
|
| HFE-7200
(C 4F 9OC 2H 5) |
0.77
-- 0.77 |
56
-- 55 |
Cleaning solvent and heat
transfer fluid.
|