Running the Eco-Numbers

A Praxis course, Donnay’s class found students working in teams to assist a community partner in examining a sustainability problem.

Team Comcast 

The Partner: Comcast’s Sustainability Division, headed by BMC Trustee Susan Jin Davis ’86, is constantly looking for ways to reduce the company’s impact on the environment while improving the communities it serves. 

Team Members: Ingrid Bethuel ’18, Madeline Cherniack ’19, Adele Hu ’18, and Sohini Maniar ’18 with Allie Wiegel ’16 from Comcast’s Sustainability Division. 

The Challenge: The Comcast fleet—one of the country’s largest—produces large quantities of greenhouse gas. What will happen if the company moves to a fully electric fleet?

The Project: The team analyzed whether making the switch to electric would produce fewer harmful emissions and make financial sense. They also asked whether the electric vehicles should be garaged at technicians’ homes or at a central garage. 

The Findings: A key finding was that operating an electric vehicle is much less expensive ($672 per year) than a gas-powered vehicle ($3,247 per year).

Team EQUAT 

The Partner: Earth Quaker Action Team (EQUAT) is a grassroots social justice organization fighting for a just and sustainable economy.

Team Members: Hee-Eun Kim ’19, Charlotte Lin ’19, Maia Rabinowitz ’20, and Nithya Sivakumar ’19 working with EQUAT members (and Bi-Co alums) Ryan Leitner ’16 and Ben Safran (HC ’13).

The Challenge: How can EQUAT persuade PECO, an energy company, to increase the amount of energy it generates from renewable sources from its current rate of 4 percent to 20 percent by 2025? 

The Project: Students calculated the “social cost” of PECO’s energy portfolio, where social cost is a measure of the negative impact that CO2 emissions have on society (estimated by the EPA to be roughly $40 per metric ton of CO2 emissions). 

The Findings: If PECO does not change its energy mix (currently 31 percent coal, 31 percent natural gas, 4 percent renewables plus nuclear), the social cost in the decade 2025–35 would reach $6.5 billion. If PECO increases renewables to 20 percent and decreases its coal use by a corresponding amount, the social cost to society over that decade drops to $2.9 billion. 

Team Freight Farm 

The Partner: Mary Cuigini ’20.

The Team Members: Leah Baker ’19, Jill Li ’18, Natalie Meacham ’19, and Bisma Naqvi ’18. 

The Challenge: What is the cost-benefit to Bryn Mawr of having an on-campus freight farm system (an up-cycled shipping container repurposed to grow produce hydroponically)?

The Project: The team studied the cost and benefits of using the system to grow produce for Bryn Mawr’s dining halls, thereby reducing the College’s purchasing costs as well as reducing its carbon footprint, because produce would not have to be trucked from far away. 

The Findings: Although the initial cost of the freight farm system would be high ($85,000), the team argued that savings over time, combined with the less quantifiable benefits (educational opportunities for students who would use the farm as a living laboratory and raising the College’s sustainability profile), would make the freight farm a positive investment.

Team Solar

The Partner: Philadelphia’s Office of Sustainability. As part of its GreenWorks sustainability master plan, Philadelphia is committed to reducing its carbon footprint and is eager to develop more renewable energy. 

Team Members: Shannon Fischer ’20, Hezel Gadzikwa ’18, Henry Nye (HC ’20), and Kaitlin Reese (HC ’20), working with Mardi Dietze and Paul Clee from Philadelphia’s Office of Sustainability. 

The Challenge: Which City-owned buildings would be most suitable to be equipped with solar panels?

The Project: Students analyzed data about solar intensities on the rooftops of City buildings.

The Findings: The students found that the majority of the buildings in their top 10 list are correctional facilities. Their projection for the #1 building, the Philadelphia Detention Center, showed that solar panels could produce a savings of $170,000 per year in electricity costs.

Team Storm Water

The Partner: Township of Havertown, PA.

Team Members: Namrata Basu ’19, Amelia McCarthy ’19, Maria Minaya ’19, and Emily Shinault ’18, working with local environmental engineer Derron LaBrake.

The Challenge: How can the Township of Havertown mitigate flooding in its Chatham Glen neighborhood? 

The Project: The team examined whether the installation of rain gardens in peoples’ yards, uphill from the flood-prone region, would significantly reduce the flooding. 

The Findings: Rain gardens alone, even if placed in every yard, would not divert enough water to prevent flooding. However, rain gardens combined with mitigation efforts on Township-owned land would significantly reduce the risk of flooding.

Over the summer, Donnay continued building on relationships with Philadelphia’s Office of Sustainability. He worked with math major Meagan Murray-Bruce ’20, who analyzed Streets Department data to carry out a cost-benefit analysis of converting street lights in Philadelphia to LED bulbs.