Yale’s 2050 zero-emissions goal applies to Yale’s direct emissions and purchased electricity (scope 1 and 2 emissions). Our focus on scope 3 has been on data collection, priority setting, and identifying opportunities for reduction impact.
Scope 3 emissions are indirect emissions resulting from Yale’s operations but from sources not owned or controlled by the university. As established by the GHG Protocol, scope 3 emissions include:
- purchased goods and services
- capital goods
- fuel- and energy-related activities
- transportation and distribution
- waste generated in operations
- business travel
- employee commuting
- leased assets
- processing of sold products
- use of sold products
- end of life treatment of sold products
- franchises
- investments
Because data for scope 3 emissions can be more difficult to obtain than scopes 1 and 2, it typically involves more assumptions. Yale is working to improve data quality so we can effectively address this significant share of our campus footprint.
What Yale Tracks
A goal of the Yale Sustainability Plan 2025 was to account for scope 3 impacts. Yale began a close analysis in 2017 and identified six Scope 3 categories as most relevant to campus operations:
- purchased goods & services
- capital goods
- fuel- and energy-related activities (FERA)
- waste generated in operations
- business travel
- employee commuting
- student travel (a category that we created in order to capture a set of emissions specific to educational institutions)
Tracking for most categories began in 2018; assessing availability of student travel data began in 2021. Yale also explored tracking investment-related emissions but lacked sufficient data.
How Scope 3 Data are Collected and Measured
Yale follows the World Resource Institute’s Scope 3 Calculation Guidance. Emissions factors are reviewed and updated annually.
- Purchased goods and services and capital goods are based on purchasing data and commodity type.
- Fuel- and energy-related activities are based on upstream emissions from extraction and transportation of natural gas to Yale, using data from scope 1 and 2 records.
- Waste generated in operations are calculated using waste tonnage (recycling, waste-to-energy processing, and anaerobic digesting).
- Business travel is based on travel booking data and reimbursement data; reimbursements are removed from purchased goods and services data to avoid double counting.
- Employee commuting is based on the university’s bi-annual transportation survey.
- Student travel data availability is under active review across Yale College and our graduate and professional schools.
By the numbers
Measuring scope 3 emissions helps Yale understand the scale of our impact as we work to refine data and set category-specific goals.
Scope 3 Collaboration
Sustainability and procurement teams from Harvard, MIT, Stanford, and Yale formed an ad hoc working group to identify a focused set of subcategories for Purchased Goods & Services and Capital Goods that are most relevant to higher education.
Together, we:
- compared each institution’s top 100 highest spend categories;
- established actionability criteria and excluded the least actionable categories;
- drew on prior Scope 3 heatmapping and materiality work to identify likely hot spots (high emissions).
The resulting shortlist includes areas most likely to be both actionable and high emissions. We hope this work enables other research universities to leapfrog the initial Purchased Goods & Services discovery stage and serve as a foundation for prioritization. Read the full paper here.