Air curtains in bus garage save energy
The Central Ohio Transit Authority’s (COTA) ongoing $75 million conversion to compressed natural gas (CNG)-fueled buses includes the HVAC retrofit of its Columbus, Ohio 400,000-square-foot CNG bus maintenance and garage areas. The retrofit is an energy-saving showcase that’s capable of Leadership in Energy and Environmental Design (LEED) silver certification someday. Eventually, COTA management wants the facility to achieve LEED certification.
Air curtains from New Castle, Pa.-based Berner International complement the project’s energy-savings specifications. The air curtains were specified on seven large 14 (h) by 16-foot (l) doorways. They retain up to 80 percent of the building’s heat during perpetual door cycles as buses enter and exit. Three additional air curtains separate environments at one large interior common doorway shared by the maintenance and garage areas.
“Using air curtains on those large doorways has proven to be a huge benefit in energy savings and indoor air comfort,” says Jon Hancock, a former COTA transportation facility manager, who oversaw much of the design.
Because of a potential natural gas leak from a bus, the air curtains, as well as the facility’s other mechanical equipment, include life/safety measures. The safety precautions include spark-proof fans, aluminum blower wheels and other components that comply with National Fire Protection Association (NFPA) governing standards for compressed natural gases and vehicle fuels.
A high-speed roll-up door activates the unit. The 16-foot-long air curtains are the longest single construction units available. They have permanent washable aluminum mesh filters that help remove airborne particulate emission contaminants from the remaining diesel fleet. The air curtains also include 708,000 Btu/hour hot water coils to provide air comfort to employees working near open doors.