Guidance on Scope 3 Emissions, pt 1: Commuting
During the first round of greenhouse gas (GHG) reporting for the ACUPCC, we heard from quite a few signatories who were struggling to calculate their emissions from commuting and air travel. These sources are responsible for a significant portion of many institutions' total emissions but they are also among the most difficult emissions sources on which to gather reliable data. The following guidance is intended to help campuses track and ultimately reduce emissions related to commuting and air travel.
It is important to note that what follows are merely suggestions based on what has worked for other schools. ACUPCC signatories should feel free to improve upon these suggestions or try completely different approaches - please just be transparent about your methodologies when reporting. We anticipate that more accurate and widely agreed upon methodologies for evaluating emissions from commuting and air travel will emerge over time. Until then, the methodologies described here should enable you to develop reasonable estimations of your institution's emissions from these sources.
Commuting Emissions
To calculate commuting emissions, you will need to determine the amount of fuel that is being used to get people to and from campus. This requires information about the number of people traveling to and from campus, how they are getting to campus, and how frequently they come to campus.
Many campuses have successfully collected such data with commuter surveys. Here are two example surveys from ACUPCC signatory campuses - Portland State University and Syracuse University. To achieve a high participation rate, most campuses make the surveys available online and easy to fill out. Some campuses also choose to give away prizes as incentives to complete the survey. Institutions can also make the surveys a requirement to participate in other programs (for example, in order to receive a parking permit a survey must be filled out). In addition to aiding with emissions calculations, these surveys also provide useful information about the commuting habits of staff and students that can be used to improve the transportation options available to them.
Your campus may also have some additional resources that will assist in estimating emissions from commuting. For example, Los Angeles Community College District (LACCD) utilizes existing databases to aid in their data collection. They have a database for all students and staff who have bought a discounted or free transportation bus pass and another database of all those who have bought parking permits. To help in estimating the emissions that occur from commuting, LACCD employs GIS software to map (by home address) all the students attending a particular college. By better understanding the distance students and faculty travel, the District can make more informed assumptions related to emissions from commuting. For example, a common assumption that LACCD has made is that any staff or student living within ¼ mile of campus will most likely walk or ride a bike to campus.
To reduce emissions related to commuting, you might consider implementing transportation management strategies such as universal transit access passes, car sharing, and bicycle sharing/rental programs.
Part 2 of this post provides guidance on how to estimate emissions from air travel
