Greenhouse Gas Inventories

A greenhouse gas (GHG) inventory measures the emissions that are released into the atmosphere as a result of university operations. This analysis provides the metric to understand and identify sources of greenhouse gas emissions and identify opportunities for reducing emissions. 

Carnegie Mellon conducts an annual GHG inventory. When reviewing annual emissions, they are compared to the baseline year, 2005, which was the first year CMU conducted a GHG inventory. 

Emission sources are defined as direct and indirect. The GHG Protocol defines these and categorizes emissions into three categories:

• Scope 1 includes direct emissions that are physically produced on campus (such as fleet fuel use or on-campus power production). These sources are “owned or directly controlled” by the institution.
• Scope 2 includes indirect emissions associated with purchased utilities required for campus operation such as purchased electricity, heat, or steam.
• Scope 3 includes induced emissions from sources that are not owned or controlled by the campus, but that are central to campus operations or activities (such as student and employee  commuting and university-paid air travel).

Carnegie Mellon has reduced Scope 1 & 2 emissions by more than 70% since 2005. This reduction can be attributed to increased building efficiency as seen in the commitment to build new buildings to meet LEED Gold and by acquiring RECs equal to the university’s electricity use. Scope 3 values fluctuate as we do not have consistent historical data or annual accounting for these details. 

Student Greenhouse Gas Inventory Projects and Reports