Variable speed drives provide such significant energy efficiency benefits that they are required by code in most new building projects. However, many older HVAC and manufacturing systems operate without them. These are ideal candidates for VSD installation.
VSDs reduce energy consumption by operating at speeds that vary over time based on changing loads. Standard pump and fan systems always run at full speed, consuming more electricity than required to do the job. A variable speed drive slows a fan or pump down when the actual load decreases.
The savings from a variable speed drive in these applications increases exponentially as the load decreases. As a result, a small decrease in speed produces a relatively large increase in savings. For example, a 20% reduction in flow can yield a savings of 35% or more.
VSDs are ideally suited for HVAC applications because the demand on heating and cooling systems can vary with outside temperature, building occupancy, and production level. Other effective applications include:
- Boiler draft fans serving boilers with varying loads
- Exhaust fans where the necessary flow rate varies with temperature, such as oven and dryer exhaust fans
- Manufacturing applications where load varies with production
Variable Speed Drives are eligible for the following incentives:
Please download this form for Variable Speed Drives, or this form for Motor and Variable Speed Drives, and contact your NSTAR representative at 1-781-441-8592 for more information.
For eligibility requirements, please refer to this form for Variable Speed Drives, or this form for Motor and Variable Speed Drives.