Green Campus Spotlight: Reducing PSU’s carbon footprint with an energy efficient cooling system
Author: Campus Sustainability Office
Posted: November 4, 2016

Working with the Energy Trust of Oregon and the City of Portland, Portland State University got a significant energy upgrade this year by replacing chillers, machines that produces chilled water to cool and dehumidify air, in the Fourth Avenue Building. Replacing chillers that were more than 40 years old, the new system is estimated to save more than $73,000 in annual energy costs. 

“The chiller project is another example of PSU’s ongoing pursuit of reaching our sustainability goals,” says Quinn Soifer, PSU engineer and lead on the project. “This project not only addresses a deferred maintenance need, but also significantly reduces our energy usage and PSU’s overall carbon footprint.”

The Energy Trust of Oregon is an independent nonprofit organization dedicated to providing clean energy solutions. Through their Existing Buildings Program, PSU and the City of Portland received a $250,000 cash-back incentive for the chiller plant upgrade that included three new high efficiency chillers. 

The Fourth Avenue Building has unique cooling needs—it houses PSU’s largest data center and several academic research labs, and supplies heating and cooling for the adjacent seven-story City of Portland Tower. Two of the new chillers use highly efficient compressors to meet cooling demands, while a third heat recovery chiller captures the heat created by the data center to heat other parts of the building. Reclaiming the heat that the building produces reduces the need to run additional equipment to heat the building, significantly increasing the building’s efficiency and saving energy.

The initial project study estimated that the upgrades would reduce the building’s natural gas consumption by 83 percent, with over $7,000 in annual savings from a reduction in maintenance. The energy savings calculated since the installation was completed in January 2016 are on par with the projected annual energy cost savings, with reductions in natural gas consumption exceeding the initial project studies estimated savings.