Campus Carbon Emissions Inventory: Commuter Contributions and Campus-Land OffsetsPaul Tanes

ptanes@bridgew.eduDarcy Boellstorff, Ph.D. dboellstorff@bridgew.edu Department of GeographyBridgewater State College, Bridgewater, MA

• Public, primarily undergraduate – 10,000 students,

350 faculty• ACU Presidents

Climate Commitment (ACUPCC)– National initiative – Greenhouse gas

inventory, short term efforts and long term plans

– Service learning opportunities

Bridgewater State College (BSC) and ACUPCC

Clean Air-Cool Planet© (CA-CP) Calculator

• Purchased electricity, steam, and chilled water

• On-campus cogeneration plant

• On-campus stationary energy use

• Transportation: Fleet and air travel

• Student commuter habits • Faculty and staff commuter

habits • Agriculture • Solid Waste • Refrigeration and other

chemicals • Emission offsets

Commuting Profile at BSC

• 7000+ student commuters – 320+ towns in

Massachusetts and Rhode Island

– Average of 4.5 trips per week

• 3000+ summer student commuters

• 1400+ employees

Students

Faculty/Staff

CA-CP© Inputs for Commuter Habits

– Number of students– Average fuel efficiency– Percent commuting by car

– Miles per trip– Trips per day– Days per year

Miles Per Trip• Town hall locations to campus• Path determined by distance and

also by speed

Trips Per Day

1. Assume all students make same number of trips per week (4.5)?

2. Trips per week varies by distance – Using the known average:

– Where: • sc = # students within 25 miles of campus,

• sm = # students 25-50 miles of campus,

• sf = # students > 50 miles of campus

• xc trips for close students

• xm for medium-distance students

• xf for far students

A

fmc

s

xsxsxs )()()(5.4 321

Annual Commuter Contribution - Automobile• 54.2 million miles (113 round trips

to the moon) using 2.5 million gallons of gasoline

• 25,000 metric tons eCO2

– Or, the amount absorbed in a year by about 5500 acres of mature trees (24 campuses)

• Contributions not yet included– Commuter rail– College fleet– College-funded travel

Offsets

– Renewable energy credit

– Composting – Forest

preservation

Forest Preservation

Forest Preservation

Forest Preservation

• 97 acres of forest• 4.5 metric tons eCO2 per acre per

year• the campus forested land offsets

437 metric tons eCO2 per year– 1.7% of automobile commuting– Need about 5400+ acres of additional forest land

Next Steps

• Regarding future estimates: More detailed survey information on commuters

• The big picture will show where we stand• Short-term action and long-term goals• GIS students and service-learning

– Web-mapping applications– Improved campus land use inventories

• Clean Air-Cool Planet©, 2006. Conducting a campus greenhouse gas emissions inventory on your campus, including instructions and documentation for CA-CP Calculator v5.0

• Stavins, R. and K. Richards, 2005. The cost of U.S. forest-based carbon sequestration. Report for the Pew Center on Climate Change.

• Duke University, 2004. Greenhouse Gas Inventory.

• American College and University Presidents Climate Commitment, http://www.presidentsclimatecommitment.org/index.php

Resources