CO2e Explained
Emissions? CO2? Carbon? GHGs? CO2e?
There is a lot of terminology to describe the global warming effects of human activities, and terms are often used interchangeably. This article will break down the different terms, including the most important one: CO2e.
What are GHGs?
Greenhouse gases (GHGs) are gases which absorb heat, trapping it in the earth’s atmosphere. In low levels, GHGs are vital for keeping the planet at a habitable temperature. However, human industrial activities in the past 150 years have increased the rate at which they are released exponentially. This has led to global warming, as too much heat is contained within the atmosphere.
There are seven GHGs, as defined by the GHG Protocol:
These gases are released in different quantities by different human activities. Some are far more efficient at absorbing heat than others, and some are released in greater quantities. As well as ‘GHGs’ or ‘greenhouse gases’, these gases are often referred to simply as ‘emissions’.
Why is carbon so important?
Carbon dioxide (CO2) is a greenhouse gas produced when organic material, such as gas, oil, coal, and biomass, is burned. It is by far the most common, making up 75% of the greenhouse gases in the atmosphere (Our World in Data, 2024). This is because of the world’s reliance upon fossil fuel generated electricity.
As a result, GHG reduction methods are usually focused on bringing down CO2 emissions. ‘Carbon’ or ‘CO2’ is therefore often used as shorthand for all GHG emissions.
What is CO2e?
Because of the prevalence of CO2 in the atmosphere, all seven greenhouse gases are usually measured in units of CO2e, or ‘carbon dioxide equivalent’. This is a way of describing the impact of each different greenhouse gas in a single unit.
Each GHG has a different global warming potential (GWP). GWP represents the amount of warming a gas can cause over a 100-year period. For example, 1 kg of nitrous oxide traps 273 times more heat than 1kg of carbon dioxide, so nitrous oxide has a GWP of 273. CO2e is therefore calculated by multiplying the amount of one greenhouse gas produced by its GWP. For example, if an activity produces 100 kg of nitrous oxide, this is expressed as 27,300 kgCO2e.
Does cloud computing release greenhouse gases?
Cloud computing primarily produces GHGs through the consumption of fossil fuel generated electricity. However, all seven GHGs are present across the cloud service supply chain.
What does this mean for my organization?
If your organization uses cloud computing services, it will be adding to the emissions of these gases into the earth’s atmosphere. In 2025, organizations of all scales, all around the world, will have to start reporting the amount of CO2e they emit through their use of cloud computing. See Tailpipe’s article, Reporting Cloud Carbon Emissions is Becoming a Legal Requirement, to find out more about how the regulations might affect your organization.
Tailpipe can measure the kilograms of CO2e emitted through your organization’s use of cloud computing, accounting for each greenhouse gas across the entire supply chain. To find out how much CO2e your organization is emitting, and to get tailored recommendations on how to reduce these emissions, get in touch with us here.
