Fanning away the heat
Construction of a new campus recreation facility for the University of Nevada, Las Vegas, called for the installation of Big Ass Fans to provide elevated air circulation within the facility.
Las Vegas is hot. With daytime temperatures hovering around 100 F for 3 months of the year, air conditioning systems work at maximum capacity. Not only does this tax the systems themselves, it results in exceedingly high energy consumption. Introducing air movement within indoor environments helps reduce the load on air conditioning systems while helping to keep occupants comfortable despite the exterior elements.
University of Nevada, Las Vegas, is no stranger to this dilemma. With 28,000 students and more than 100 buildings comprising UNLV’s campus, the university consumes a great deal of air conditioning. Construction of a new campus recreation facility called for the installation of Big Ass Fans to provide elevated air circulation within the facility. Soon after, the Tonopah Residence Complex installed one to help reduce the workload on the air handling system.
Built in 1966, the Tonopah Residence Complex is a six-story residence building in the center of the UNLV campus, whose lobby is home to the Office of Housing Services. Debilitating air circulation problems existed within the 900-sq-ft lobby, making it uncomfortable for the employees who work there and for the continuous stream of students who pass through to pay bills, make housing inquiries, or make their way to their apartments. With a temperature differential of at least 15 degrees in the complex’s 16-foot-high, two-story lobby, HVAC specialist Jim Stinar was unable to address the vertical temperature discrepancy. Summers left the space too hot as the air handling system could not keep up, and winters left the lower occupant level too cold while the balcony was stifling.
Up against both financial concerns associated with increasing the tonnage on his air handling system and the increased energy it would consume, Stinar opted instead to install Big Ass Fans’ 8-ft large-diameter, low-speed Isis fan in the space to work with the existing unit.
Despite the 16-ft ceiling, installation of the fan was straightforward. Still benefiting from the air handling unit originally installed in the building 50 years ago, one solution involved the installation of split DX units that would have been cost-prohibitive considering the amount of piping required.
Having observed Big Ass Fans in the UNLV recreation center, Stinar was sold on the concept. “I knew fans would help the situation but I didn’t think typical, small fans would do the trick,” he said. He had looked into adding a 1-1/2 to 2-ton air handling unit to the space, but it would have been costlier and more labor-intensive, considering, as he stated, “the fan was much easier to install than having to run additional piping.”
Large-diameter, low-speed fans can either work in tandem with HVAC systems or on their own to distribute air more efficiently over large spaces where, through destratification, circulating the air in the space can help maintain a constant temperature. Significantly larger than traditional ceiling fans, these 6‐ to 24‐ft diameter fans are meticulously engineered to effectively circulate air in any environment. Though large and powerful, they are also energy-efficient, using very small motors, particularly relative to the volume of air movement generated.
In lieu of increasing the tonnage on his existing air handling system, Stinar is able to raise the setpoint on the thermostat several degrees, saving $200 to $400 annually in conditioning costs. This is in addition to the cost savings accrued by upgrading the cooling system. Winter savings also accrue by circulating heat trapped at the ceiling down to the occupant/thermostat level. Even though the thermostat setpoint remains the same, the heating system does not have to work as hard to maintain the given setpoint. Circulating the air is similar to turning the thermostat down 5 to 7 degrees.
Working with the existing air handling system, the fans provide air movement and regulate temperatures within the two-story lobby, improving comfort and reducing energy costs and consumption.
Information provided by Big Ass Fans.