Environmental Leader

The methodology used for calculating a company’s carbon footprint depends on what they are trying to measure. The Greenhouse Gas Protocol developed by the World Resources Institute and World Business Council on Sustainable Development is the standard for calculating a corporate footprint. Many companies chose to calculate Scope 1 and 2 emissions because these are the only emissions that can be accurately calculated or will be subject to any regulation, and the scope 3 emissions are someone else’s scope 1 or 2 emissions. A company wouldn’t construct an income statement using the income and expenditures of its buyers and suppliers. Why should it do this in carbon accounting?

Estimating the financial and greenhouse gas positions of buyers and suppliers is useful in understanding a firm’s exposure to the market and potential regulations. However, estimates have inherent inaccuracies. Companies which want to account for these scope 3 emissions should request that their buyers and suppliers conduct greenhouse gas inventories. Companies wishing to calculate the GHG generated over a product’s lifecycle should use the Supply Chain protocol at http://www.ghgprotocol.org

I found the Carnegie Mellon press release to be misguided and self-serving.

Juan | August 20th, 2008

I would have to agree with Juan’s comments. This press release from Carnegie is only making a “The Sky is Blue” statement. Not only would a companies buyers and suppliers have to report their Scope 1 and 2 emissions, but carve out the percentage of emissions for each customer. At which point, those emissions would become Scope 3.

David | August 22nd, 2008

This article incorrectly refers to the GHG Protocol’s “Tiers.” What the writer is actually referring to is Scope 1, 2, & 3. The Tiers, on the other hand, indicate the data quality. Higher Tiers mean more exact activity data is being used, lower Tiers mean that less accurate data is available.

Pablo | November 21st, 2008