Swarthmore College
IN-27: Innovation D

The Energy Strategy for Sustainability and Resiliency (ESSR) assessed Swarthmore's aging campus utility infrastructure in order to develop a cost-effective and forward-thinking plan to prioritize replacing or upgrading existing heating and cooling systems, in order to improve reliability, increase efficiency, and ensure proper capacity while our campus continued to expand. The ESSR integrates a campus master utility plan, a facilities condition assessment, and renewables strategy, and an energy capital investment plan.

As part of a renewed effort to understand potential energy strategies the College engaged the services of two consulting firms to help develop the ESSR. The first was Carbon Lighthouse who were charged with examining our Science Center and Chiller Plant for potential energy savings. The second was The Stonehouse Group who were initially hired to examine an emergency power plan but their role was expanded to take a holistic view of energy planning in the context of existing infrastructure and new construction.

Carbon Lighthouse installed a series of sensors to track actual performance of air handlers and other equipment, comparing it to ideal operating conditions for maximum savings. What their report demonstrated was how far the equipment had drifted from design operation and the fact that some sensors that were supposed to be controlling that operation were either not functioning or out of calibration. While we have not initiated all of the recommendations, initial experiments with supply air temperature reset and duct static pressure reset demonstrates that there is potential to reduce electric consumption by at least 380,000 kWh per year in air handler operation alone.

The Stonehouse Group was asked to take a look at the College’s overall energy strategy and a major new building, BEP, being planned that featured ground source heat pumps as the means to heat and cool the structure. What struck them was the amount of disruption to the campus as the wells were more than a thousand feet from the structure, and the fact that the Campus steam heating infrastructure was aging and provided poor energy efficiency in the shoulder seasons that were getting longer every year. They saw the new construction as an opportunity to think of a showcase energy efficient campus rather than a showcase energy efficient building. They made the recommendation to the College and the design engineers that we consider a hot water distribution system with hot water condensing boilers to serve all of the buildings currently served by steam. These would be in place of the ground source heat pumps. Heating with hot water is inherently more efficient estimated at 75% end use efficiency vs. steam at 48% end use efficiency. When fully implemented the campus would be able to take advantage of Combined Heat and Power for supplying some of our power needs as well as the potential to utilize Bio fuels in a central plant. That would greatly reduce our carbon contribution.