New Orleans is known for its old world charm which often means antiquated heating and cooling systems that are no match for the sweltering heat and humidity. With the newly remodelled Lavin-Bernick Center (LBC) on the uptown campus of Tulane University, student’s lives have become a bit breezier thanks to the installation of several Big Ass Fans.

The initial groundbreaking for the expansion of the student centre started in 2003. After a brief delay from the devastating effects of Hurricane Katrina in 2005, the 33 percent expansion of the existing 100,000 sq. ft. student centre continued.  Construction forged on and the 151,000 sq. ft. structure was completed in 2007.

The environmentally-friendly design uses various shading and ventilation techniques utilizing natural air and lighting to help ventilate and cool the area. Foregoing the installation of a traditional HVAC system, LBC incorporates these passive cooling techniques, and three 10-foot diameter Big Ass Fans® in order to keep the space comfortable for its 10,000 daily visitors. In 2008, the project was chosen as an AIA Committee on the Environment Top Ten Green Project, which awards projects incorporating sustainable, efficient, community and environmental attributes. According to Leland Bennet, director of LBC, Big Ass Fans certainly contribute to the environment. “Big Ass Fans are a unique addition that adds to the ambience and comfort of the building,” affirms Bennet.

So how do Big Ass Fans work? From a technical perspective, Big Ass Fans function on a simple physical principal: unlike small, high velocity fans that create small turbulent air streams which dissipate quickly, a large, slow moving fan entrains a significant amount of air. The air current from a Big Ass Fan approaches floor level in a conical column that radiates out in all directions. The horizontal air jet continues until it reaches walls or airflow from another fan, at which the airflow is turned upward and back in toward the fan. This creates convection-like air currents that gather inertia as the fan continues to spin. The increased air circulation improves heat loss by removing hot, humid air from contact with the skin and replacing it with relatively drier air. The end result is a silent, non-disruptive distribution of 3-5 mph breezes over large spaces.

Because of its size, the high volume/low speed fan is both effective and efficient. Using ¾-2 hp motors, they consume power at a mere fraction of the cost that small ceiling fans require. Relying on their immense size, not speed, the fans effectively circulate air throughout the mezzanine area of LBC, replacing 16 inefficient ceiling fans. During the winter, the temperature between the floor and the ceiling may vary by 15°F. Big Ass Fans are slowed to redistribute warm air collecting at the ceiling level down to the occupancy level. The rule of thumb is that for every degree dialled down on the thermostat, you can enjoy a 3% reduction in energy costs. As a result, many customers accrue savings of 25% or more during a heating season.

Over 100 universities nationwide have installed Big Ass Fans, with a variety of purposes cited ranging from energy reduction to heat recirculation. Sustainability-focused construction can even apply Big Ass Fans for LEED (Leadership in Energy and Environmental Design) credits in seven different categories, making them a useful addition to any green building project.

Tulane University decided to forego the old-fashioned alternative provided by a traditional HVAC system. Big Ass Fans, incorporated to increase thermal comfort and reduce energy costs, are an efficient solution to rising fuel costs and an emergent alternative for the academic world.

Source: Big Ass Fans

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