Sustainability has Chilled the Electric Bills at CowellNew Air Conditioning uses Half the Energy of the Previous Component
Many improvements made at University of the Pacific's Stockton campus to increase energy efficiency and sustainability are evident to the naked eye. Others require closer inspection. Projects that have made the campus less taxing on the environment and are readily evident include the installation of solar panels on the John T. Chamber's Technology Center, the installation of energy-efficient lights in the Quad and other areas of campus, and more robust recycling and composting efforts.
But not all of these changes are apparent. Some have to be felt.
Case in point: the replacement chiller on the air conditioning system in the Cowell Wellness Center uses less than half the energy than that of a conventional cooling unit. In fact, it uses so little energy campus officials estimate it will save as much as $150,000 in cooling costs over the next two decades.
The effort to reduce energy costs for an existing building happened thanks to a unique collaboration between employees at Pacific's Physical Plant and a professor and three students in the School of Engineering and Computer Science.
"The Cowell project took us about two semesters to complete, because it required a lot of modeling and studies of the building," said Jay Brink '13, an electrical engineering major, who worked last school year with Steve Brown '13 and Michael Roberts '13. The trio was supervised by Professor Cherian Mathews.
"We had to create a thermodynamic model of the Cowell building so we could figure out sources of heat and how long those sources produced heat," Brink said. "For example, we calculated how long lights would be on in the building during different times of year. We took into account body heat, looked at the size and location of windows and calculated the intensity of daylight through the windows throughout the years. Using that model, we calculated how much cooling will be needed at any time during the year."
The impetus for the project was the need to replace the "chiller" on the building, a 43-year-old piece of machinery that cools water in the air conditioner. The cooled water flows through metal pipes in the building, causing a chilling effect, and air is blown over those pipes, which produces the air conditioning effect often appreciated during the 100-plus during summer days.
The new chiller uses 52.4 percent less power than the old chiller. That will result in about $8,600 less in electrical costs annually, according to a report completed by Professor Mathews and the students. The replacement project was designed, engineered and completed entirely by Physical Plant personnel.