According to a recent study, more than 25 percent of the energy consumed in commercial buildings is used for heating and air-conditioning. Of that, a good portion (anywhere from 20 to 60 percent) is consumed by the fans and pumps that transfer heated or cooled air or water from central heating and cooling plants to conditioned spaces. Supply and exhaust fans are the major players, primarily because most fans operate continuously while the building is occupied. There is a wide variation in efficiency between different fan designs (from as low as 40 to as high as 80 percent). In light of their long operating hours and wide-ranging efficiencies, HVAC fans are often good candidates for energy-efficiency retrofits.

In addition to the efficiency of the fan itself, the low cost and wide availability of variable-frequency drives in all horsepower ranges make this technology an important part of most energy-efficiency upgrade strategies.

What are the options?
How to make the best choice
What’s on the horizon?
Who are the manufacturers?