Greenhouse gases

Carbon Dioxide isn’t the only greenhouse gas. Going from the least potent to the most potent, they are:

• Methane (CH4) – sources include natural gas and cattle (contrary to popular belief, the methane usually comes from the front end of the animal chewing the cud, not the rear end!)
• Nitrous Oxide (N2O) – natural sources include soils under natural vegetation and atmospheric chemical reactions, but non natural sources include diesel engines and burning biomass
• Chlorofluorocarbons (CFCs) and Hydrofluorocarbons (HCFCs) – There are no natural sources of CFCs or HCFCs, but they were used in aerosols, fridges and air conditioning units. CFCs were banned in 1996, and HCFCs were banned in 2001 due to the damage they did to the ozone layer, as well as being greenhouse gases
• Sulphur Hexaflouride (SF6) – There are no natural sources of Sulphur Hexafluoride but it does have some very specific industrial applications such as being used in high voltage switch gear (SF6 is a very good electrical insulator.)

Please watch the video on which Greenhouse Gas is worst for more information on global warming potentials.

Famously, Nike used SF6 in its bubble for the Nike Air trainer from 1989 to 2006. The table below will hopefully tell you how bad an idea it was to use it!

Note – When comparing greenhouse gases to each other for Carbon Footprint reporting, everything is related back to CO2, and therefore you will see the term “CO2e” (or Carbon Dioxide Equivalent). This is just a way of saying that something has the equivalent global warming potential as releasing (x) amount of CO2.

For example, 1kg of Sulphur Hexafluoride is approximately 22.8 tCO2e (tonnes, Carbon Dioxide equivalent)