Jeff Scanes, Johnson Controls

All-air VAV system versus chilled-beam-system energy consumption at design and part-load conditions

At full design load and at 72% of design load, both systems must deliver the same amount of cooling to the space to maintain room temperature set point. Further reduction of load in the room results in all-air VAV systems delivering the same level of cooling and having to offset overcooling with parasitic reheat. Chilled-beam systems are able to reduce energy consumption by reducing cooling delivered to the space without the use of parasitic reheat.