CO2 equivalents (CO2e)

The term “CO2 equivalents” (CO2e) is used to measure and compare greenhouse gas emissions from different sources in a single unit. Greenhouse gases such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and others have different abilities to warm the Earth’s atmosphere. The use of CO2 equivalents makes it possible to express these gases in a common unit based on their Global Warming Potential (GWP) compared to CO2.

Why CO2 equivalents are important:

Comparability: CO2 equivalents make it possible to compare and aggregate greenhouse gas emissions from different sources (e.g. CO2 from fossil fuel combustion and methane from livestock).

Climate change assessment: They are a key element in assessing overall emissions and their contribution to climate change.

Policy and regulation: Many climate change policies and regulations use CO2 equivalents as a benchmark for setting emissions targets and standards.

Global Warming Potential (GWP):

GWP is an important component in the calculation of CO2 equivalents. It assesses the ability of a greenhouse gas to store heat in the atmosphere over a certain period of time, usually 100 years. CO2 has a GWP of 1 and serves as a reference point. Methane, for example, has a much higher GWP than CO2, as it is significantly more heat-relevant in the first few years after release, but is then broken down more quickly.

Example for CO2 equivalents:

Assume a company emits 10,000 tons of methane and 20,000 tons of CO2 per year. To convert these emissions into CO2 equivalents, the GWP would be used. For example, if the GWP of methane over 100 years is 25, you would multiply the methane emissions: 10,000 tons of methane x 25 (GWP of methane) = 250,000 tons of CO2e. The company’s total emissions would then be 20,000 tons of CO2 + 250,000 tons of CO2e methane = 270,000 tons of CO2e.

Significance for climate protection:

The use of CO2 equivalents is critical to understanding the total contribution of various greenhouse gases to climate change. Efforts to reduce greenhouse gas emissions aim to reduce not only CO2, but also other gases that contribute to the greenhouse effect. By using CO2 equivalents, countries, companies and organizations can better track their progress in reducing overall emissions and minimize their impact on the climate