Document Type


Publication Date



This project was a collaboration between students taking the environmental studies capstone course and community partners Julie Rosenbach and John Rasmussen with the purpose of supplementing current research on sustainable and cost effective energy sources at Bates College, by examining externalities. In order to compare and contrast the externalities of a fossil fuel against a feasible alternative energy, focus was placed on natural gas and biomass. The overall goal of the project was to elucidate the positive and negative impacts of different energy options on the environment and society, leading to a recommendation of the best energy option for Bates College.

Consideration for sustainable practice on the Bates College campus began in 2007 when the college president at the time, Elaine Tuttle Hansen, signed the American College and University Presidents Climate Commitment (Climate Action Plan 1). This action initiated a campus wide effort to reduce greenhouse gas (GHG) emissions to the extent of achieving climate neutrality. In other words, Bates made mitigation of current emissions and offsetting immitigable emissions a priority in the attempt to have zero GHG emissions. To outline this process, Bates College generated the Climate Action Plan (CAP) in 2010, which identified sources of emissions on campus and provided three different plans to achieve climate neutrality. The document highlights the role of fossil fuels as a significant source of GHG emissions and presents biomass as a possible mitigation strategy (CAP 21). Although the positive and negative implications of these energy sources in regard to GHG emissions is clearly stated and well supported in the CAP, the positive and negative implications of energy sources in other important realms of sustainable thought, such as the environment and society were not considered in depth.

To supplement the research on GHG emissions, this project identified and analyzed externalities of natural gas and biomass relevant to Bates College. These externalities, defined as societal and environmental costs not reflected in the market price of fuel (Koomey et. al. 1), were organized into five different categories and each category was ranked on a scale of 1 to 10, with one representing an energy source that consists of extremely negative externalities and ten representing an energy source that consists of extremely positive externalities. For each ranking an analysis of the externalities and for each category a comparative examination of the energy sources was included.

This project found that biomass was not only the best option to mitigate GHG emissions on campus, but the best energy option for Bates College when considering the externalities of the two energy sources. In all five categories, biomass ranked higher than natural gas. At the time of this project, nearly five years after the publishing of the Climate Action Plan, fossil fuels are still being used on campus. The results of this project show that the initial investment to change the main steam plant’s infrastructure from fossil fuels to biomass is well worth the money, considering the environmental and societal implications in addition to the reduction of GHG emissions.