| Fuel | CO2 Emissions Factor (kgCO2/kWhth) |
| Coal and lignite | 0.333 |
| Coke oven gas | 0.338 |
| Ethane | 0.191 |
| Fuel oil | 0.267 |
| Gas oil | 0.279 |
| Hydrogen | - |
| Methane | 0.184 |
| Mixed refinery gases | 0.246 |
| Natural gas | 0.184 |
| Unknown process gas | 0.246 |
| Name | Formula | Lifetime (years) |
Radiative Efficiency (Wm-2ppb-1) |
Global Warming Potential * |
| Carbon dioxide | CO2 | variable | 1.4x10-5 | 1 |
| Methane | CH4 | 12 | 3.7x10-4 | 21 (23)** |
| Nitrous Oxide | N2O | 114 | 3.03x10-3 | 310 (296) |
| HFCs | 134a=CH2FCF3 | 14 | 0.16 | 140-12,100 (120-12,000) |
| Sulphur Hexaflouride | SF6 | 3200 | 0.52 | 22,800 (22,200) |
* GWP, or Global Warming Potential allows scientists and policymakers to compare the ability of each greenhouse gas to trap heat in the atmosphere relative to other gases. GWP is the ratio of radiative forcing (both direct and indirect) from 1kg of greenhouse gas to 1kg of CO&sub2 over a period of 100 years (as recommended by the IPCC, the Intergovernmental Panel on Climate Change)
** Main figures are from the Third Assessment Report (TAR), figures in brackets are from the Second Assessment Report (SAR)