We consider carbon footprint to be the most reliable environmental impact data available. It represents the greenhouse gases emitted from the materials sourcing, manufacturing and transportation of consumer products. Because this is at the center of the climate challenge, carbon footprint data is a significant component of our methodology.
To calculate carbon footprint, first we look at each product’s ‘CO2e footprint’. The ‘e’ is for “equivalent” which incorporates all greenhouse gases including carbon dioxide and methane. It’s measured “cradle-to-gate,” which includes materials extraction and processing, manufacturing, and transportation. This data comes directly from cloud-based lifecycle inventories including ecoinvent, through a tool called the 2030 Calculator.
It’s helpful to know the carbon footprint of a product, but it only tells you so much when you’re shopping. There’s huge variability between products both across and within shopping categories; how does one compare small pans to big ones, or say a blender to a butter knife?
To make it easier for consumers to evaluate a product’s relative carbon footprint, we include an absolute CO2e footprint score, along with a functional score called a ‘carbon efficiency ratio,’ which is calculated as CO2e/kg. The carbon efficiency ratio is a good indicator of which products are using the most carbon efficient materials, processes and transport.
Using this method, we can also spot outliers within a shopping category that drive outsized cost to the environment for the utility that a product offers, either from an absolute or relative CO2e footprint perspective. When we find one of those products, we remove it from our catalog.
As Everlastly rates more and more products within a shopping category, the accuracy of the relative scores improve and the model moves towards a detailed picture of true environmental cost.