Shoemaker Green


Penn Offsets Carbon Emissions from Air Travel

November 1, 2022
airplane in flight

The University of Pennsylvania has begun purchasing carbon offsets for Penn’s air travel emissions, as part of its plan to achieve carbon neutrality by 2042.The offsets purchased through the Travel Sustainability Fund - Penn's first offset purchases related to its air travel emissions - will be supported by a Climate Impact Offset charge (CLIO) applied to Penn's schools and centers that make travel-related purchases. This will be the first time Penn has purchased offsets specifically related to its air travel emissions.

Air travel comprises 5-10% of Penn’s main campus carbon emissions. Penn faculty, staff and students who travel on university business are encouraged to choose more sustainable transportation methods when possible, but it is acknowledged that some level of air travel will continue within the Penn Community.

An Air Travel Working Group of faculty and staff designed the CLIO process. Penn Procurement records the number of domestic and international flights from each school or center and charges them a pre-set fee for each. The funds are gathered into a central Air Travel Sustainability Fund, which is used to purchase offsets.

Penn is committed to funding only high-quality offset projects. Projects must meet or exceed Second Nature’s Carbon Markets and Offset guidance, address environmental justice impacts, and, where relevant, follow the UN Declaration on the Rights of Indigenous Peoples. A newly established Air Travel Offset Selection committee is responsible for selecting projects in accordance with these guidelines.

A nitrous oxide (N2O) abatement project is the first investment from Penn’s Travel Sustainability Fund. This is regarded as a compensating action to destroy or eliminate an appropriate amount of nitrous oxide to compensate for the jet fuel burned when Penn faculty and staff fly on planes.

"The University selected this project because we could easily verify the destruction of the nitrous oxide, a powerful greenhouse gas," explained Dr. Benjamin Pierce, Professor of Computer and Information Science and a member of the Air Travel Offset Selection committee.

“The Penn Sustainability Office, Penn Procurement, and expert faculty all came together in the Air Travel Working Group to develop and implement this innovative program that can only be found at a few other higher education institutions. As we learned from other schools, we hope to help other institutions develop similar programs.” said Nina Morris, Director of Sustainability with the Penn Sustainability Office

 “I was delighted to see the CLIO charge when I purchased an airline ticket through World Travel for upcoming travel to South Africa,” noted Dr. Alison Buttenheim, Professor of Nursing and Health Policy and a member of Penn’s Committee for the Institutional Response to the Climate Emergency (CIRCE). “It’s critical that we recognize the climate impact of research-related travel. The CLIO charge is a straightforward and transparent way to do that.”

Penn considers purchasing offsets only in situations where other options are not viable, as supplements to its ongoing and accelerating efforts to reduce emissions, such as through regular, cyclical recommissioning of its campus buildings, and the creation of energy from renewable sources, such as will be generated through Penn’s recent solar power purchase agreement (PPA).

This is Penn’s first carbon offset purchase for air travel, but Penn has previously purchased offsets to address carbon emissions from steam purchased by Penn to heat and cool its buildings.

Find more information on this offset purchase on the attached FAQ document.


Penn Sustainability is a University-wide initiative to advance social, environmental, and economic sustainability at the University of Pennsylvania, and coordinate programs to develop a more sustainable campus. Visit Questions? Contact

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