Because many laboratory facilities require 100% makeup air for workstation environments, Neurogen Corp. in Branford, Connecticut, looked for ways to cut its high energy costs at a new facility for chemical research. Tri-Stack systems were used for laboratory workstation fume hood exhaust to eliminate re-entrainment possibilities into the building’s ventilation system; heat recovery coils filled with a solution of glycol and water at the 20,000 sq.ft. building extract heat from workstation fume hood exhaust before it is discharged above the roofline, reducing the need for natural gas to pre-heat (or pre-cool) makeup air. The Tri-Stack/heat recovery system increases intake air temperature by 10° F, resulting in a 30% reduction in heating energy costs.