Field Review: Chilled Beams Net Cool Savings at Clemson University
Sometimes it pays to wait.
That is the case with a new 100,000-sq.-ft. life sciences building currently under construction at Clemson University in Clemson, SC, a project that DPR restarted in 2010 after it was put on hold for two years due to state funding. The delay allowed the university to incorporate the latest iteration of a chilled-beam technology for the building’s mechanical cooling system—a progressive, sustainable building component that will net long-term cost savings and help achieve an overall goal of 10.5 percent energy reduction compared to a traditional structure.
A still-emerging technology that is also being used in a San Francisco Bay Area office building project for the David and Lucile Packard Foundation, the chilled-beam system offers the ability to significantly reduce primary air-flow requirements for space conditions in a building. The Trox® active chilled-beam system installed in the Clemson facility uses preconditioned primary air, supplied at 55 degrees Fahrenheit, which is delivered from the air handler via duct into the beam’s nozzle chamber. Forcing the primary air through rows of induction nozzles creates a negative pressure, which draws room air through the beam’s face and its chilled water coil. The room air is cooled and then mixed with the primary air jets before the mixture is discharged to the space, creating a convection cooling cycle. The use of this particular type of active chilled-beam system reduces the amount of air needed to serve conditioned spaces by approximately 35 percent, resulting in reductions in the overall size of air-handling unit (AHU) requirements by up to 82 percent when compared to a traditional variable air-volume system.
The Clemson University life sciences building, targeting LEED® Gold certification, represents just the second installation of the high-efficiency Trox chilled beams in the region. The first installation was on a project at nearby Furman University in Greenville, SC. DPR Project Engineer Kali Cadle points out that the Clemson project’s original design called for a traditional chilled-beam system as one of its primary green features, but during the two-year hiatus, Trox rolled out the new high-efficiency version of the chilled beams that was incorporated into the current project. While yielding the same output, the newer system uses fewer and much smaller chilled beams than the previous system—just 242 compared to 318 beams—delivering additional savings of $40,000.