Under Section 40A of the Environmental Protection and Management Act (“EPMA”), “global warming potential”, in relation to a greenhouse gas or a blend or mixture of greenhouse gases, means the climatic warming potential of the greenhouse gas or the blend or mixture (as the case may be) relative to the climatic warming potential of carbon dioxide (calculated in terms of the 100-year warming potential of one kilogram of the greenhouse gas or the blend or mixture of greenhouse gases (as the case may be) relative to one kilogram of carbon dioxide), as published and updated from time to time on the Agency’s official website.
For the purposes of Section 40A of the EPMA, the Global Warming Potential (“GWP”) of a greenhouse gas (“GHG”) shall refer to any value specified under the third column of the table below corresponding to the specified substance or chemical formula in the first and second column of that table opposite the value respectively.
| First Column | Second Column | Third Column |
S/N | Greenhouse Gas | Chemical formula of greenhouse gas | Global Warming Potential (100-year)1 |
1 | Carbon dioxide | CO2 | 1 |
2 | Nitrous oxide | N2O | 265 |
3 | Methane | CH4 | 28 |
4 | Sulphur hexafluoride | SF6 | 23,500 |
Hydrofluorocarbons (HFCs): |
5 | HFC-23 | CHF3 | 12,400 |
6 | HFC-32 | CH2F2 | 677 |
7 | HFC-41 | CH3F | 116 |
8 | HFC-125 | CHF2CF3 | 3,170 |
9 | HFC-134 | CHF2CHF2 | 1,120 |
10 | HFC-134a | CH2FCF3 | 1,300 |
11 | HFC-143 | CH2FCHF2 | 328 |
12 | HFC-143a | CH3CF3 | 4,800 |
13 | HFC-152 | CH2FCH2F | 16 |
14 | HFC-152a | CH3CHF2 | 138 |
15 | HFC-161 | CH3CH2F | 4 |
16 | HFC-227ca | CF3CF2CHF2 | 2640 |
17 | HFC-227ea | CF3CHFCF3 | 3,350 |
18 | HFC-236cb | CH2FCF2CF3 | 1,210 |
19 | HFC-236ea | CHF2CHFCF3 | 1,330 |
20 | HFC-236fa | CF3CH2CF3 | 8,060 |
21 | HFC-245ca | CH2FCF2CHF2 | 716 |
22 | HFC-245cb | CF3CF2CH3 | 4,620 |
23 | HFC-245ea | CHF2CHFCHF2 | 235 |
24 | HFC-245eb | CH2FCHFCF3 | 290 |
25 | HFC-245fa | CHF2CH2CF3 | 858 |
26 | HFC-263fb | CH3CH2CF3 | 76 |
27 | HFC-272ca | CH3CF2CH3 | 144 |
28 | HFC-329p | CHF2CF2CF2CF3 | 2,360 |
29 | HFC-365mfc | CH3CF2CH2CF3 | 804 |
30 | HFC-43-10mee | CF3CHFCHFCF2CF3 | 1,650 |
31 | HFC-1132a | CH2=CF2 | 1 |
32 | HFC-1141 | CH2=CHF | 1 |
33 | (Z)-HFC-1225ye | CF3CF=CHF(Z) | 1 |
34 | (E)-HFC-1225ye | CF3CF=CHF(E) | 1 |
35 | (Z)-HFC-1234ze | CF3CH=CHF(Z) | 1 |
36 | HFC-1234yf | CF3CF=CH2 | 1 |
37 | (E)-HFC-1234ze | trans-CF3CH=CHF | 1 |
38 | (Z)-HFC-1336 | CF3CH=CHCF3(Z) | 2 |
39 | HFC-1243zf | CF3CH=CH2 | 1 |
40 | HFC-1345zfc | C2F5CH=CH2 | 1 |
41 | 3,3,4,4,5,5,6,6,6-Nonafluorohex-1-ene | C4F9CH=CH2 | 1 |
42 | 3,3,4,4,5,5,6,6,7,7,8,8,8-Tridecafluorooct-1-ene | C6F13CH=CH2 | 1 |
43 | 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10, 10-Heptadecafluorodec-1-ene | C8F17CH=CH2 | 1 |
Perfluorocarbons (PFCs): |
44 | PFC-14 | CF4 | 6,630 |
45 | PFC-116 | C2F6 | 11,100 |
46 | PFC-c216 | c-C3F6 | 9,200 |
47 | PFC-218 | C3F8 | 8,900 |
48 | PFC-318 | c-C4F8 | 9,540 |
49 | PFC-31-10 | C4F10 | 9,200 |
50 | Perfluorocyclopentene | c-C5F8 | 2 |
51 | PFC-41-12 | n-C5F12 | 8,550 |
52 | PFC-51-14 | n-C6F14 | 7,910 |
53 | PFC-61-16 | n-C7F16 | 7,820 |
54 | PFC-71-18 | C8F18 | 7,620 |
55 | PFC-91-18 | C10F18 | 7,190 |
56 | Perfluorodecalin (cis) | Z-C10F18 | 7,240 |
57 | Perfluorodecalin (trans) | E-C10F18 | 6,290 |
58 | PFC-1114 | CF2=CF2 | 1 |
59 | PFC-1216 | CF3CF=CF2 | 1 |
60 | Perfluorobuta-1,3-diene | CF2=CFCF=CF2 | 1 |
61 | Perfluorobut-1-ene | CF3CF2CF=CF2 | 1 |
62 | Perfluorobut-2-ene | CF3CF=CFCF3 | 2 |
Hydrocarbon (HC): |
63 | Isobutane | HC(CH3)3 | 1 |
Hydrofluoroolefin (HFO): |
64 | (E)-1-Chloro-3,3,3-trifluoroprop-1-ene | trans-CF3CH=CHCl | 1 |
Note 1: GWP values are based on Table 8.A.1 of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, except for Isobutane which is based on Appendix Table A-1 of the Scientific Assessment of Ozone Depletion (2018). GWP Values of less than 1 are approximated to 1.
The GWP of a blend or mixture is calculated as a weighted average, derived from the sum of the mass fractions of the individual components found in the blend or mixture multiplied by their corresponding GWP. For a blend or mixture containing
N components,
GWP of blend or mixture = Mass fraction of Component 1 x GWP of Component 1 + Mass fraction of Component 2 x GWP of Component 2 + … + Mass fraction of Component N x GWP of Component N
Example 1: R-408A
R-408A composition: 46% HFC-143a + 7% HFC-125 + 47% HCFC-22
GWP of Blend (R-408A) = 0.46 x 4,800 + 0.07 x 3,170 = 2,429.9 (rounded to 2,430)
Example 2: R-455A
R-455A composition: 21.5% HFC-32 + 75.5% HFC-1234yf + 3% CO2 (R-744)
GWP of Blend (R-455A) = 0.215 x 677 + 0.755 x 1 + 0.03 x 1 = 146.34 (rounded to 146)