The e in CO2e stands for equivalent. But let's first clarify what we mean by equivalence: Equivalence is a relationship between two statements that are not identical in content but have something in common, such as being true or false.

In relation to climate change, greenhouse gases all have the ‘true’ commonality of having a negative impact on global warming. However, they do so with varying intensity.

In order to compare the intensity of greenhouse gases and quantify and evaluate emissions from a cocktail of greenhouse gases, they have been converted into CO2 equivalents (CO2e) using the Global Warming Potential (GWP). The GWP standardises the effect of all greenhouse gases to the effect of CO2, which is probably the best known greenhouse gas as it is the one most emitted by humans.

According to the Kyoto Protocol and the Greenhouse Gas Protocol of the IPCC (Intergovernmental Panel on Climate Change), the following greenhouse gases are included: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and fluorinated greenhouse gases. F-gases are hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6). Nitrogen trifluoride (NF3) was added to the list around 10 years ago.

Carbon dioxide (CO2) has a GWP value of 1, while methane is approximately 27 times more potent than CO2 per kilogram and therefore has a GWP of 27 CO2e. If 1 kg of CO2 is released together with 1 kg of methane, this results in total emissions of 28 kg of CO2 equivalents. All GWP values can be found in the link below.

What is the purpose of the conversion? We, as well as companies, are interested in knowing how much emissions are generated in which processes and what can be done to reduce them to net zero wherever possible. This allows us to determine a carbon footprint, a balance sheet that expresses how sustainable a company is. Companies in the EU that meet certain size criteria are now required to publish a CO2 balance sheet in a sustainability report on a regular basis. For environmentally conscious consumers, the CO2 balance sheet then serves as a guide or advisor when choosing products.

Did you know? – Together towards net zero!