Variable Frequency Drives

VFDs adjust motor speed to match the work being performed. In most systems, reducing a motor’s speed by 50% causes a 75% drop (or more) in energy consumption. But VFDs aren’t right for every application. Residential well pumps, for example, are 100% on or off, so adding a VFD could decrease the pump’s efficiency. Applications where VFDs make sense include HVAC and industrial-process circulating pumps. If you have questions about VFDs and your application, call us.

  • VFDs match the motor speed to the work being performed
  • Well suited for many commercial and industrial applications
  • A VFD acts as a soft start, reducing wear and extending motor life

Watch the VFD Overview Training presented by Efficiency Vermont.

Pumps and Fans

Pumps and fans are used in applications as varied as swimming pools, industrial processes, machine tools, HVAC systems, and wastewater plants. To size a pump or fan, start by determining how much fluid you need to move over time and against what pressure. Then choose a pump or fan with a Best Efficiency Point (BEP) meeting those specifications. Keep in mind, however, that the BEP should be matched to the most frequent (not necessarily the highest) expected load levels. Select for the most frequent load to save the most energy.


Efficient motors save both energy and money. Sizing a motor for its intended use is important, since a partially loaded motor is far less efficient than one running at 75% capacity or higher. Motors rated “Premium Efficiency” deliver the minimum allowed efficiency levels. Call us for guidance on whether a higher-efficiency motor makes sense for you. And if you do purchase a Premium Efficiency motor, look for one tested by the National Electrical Manufacturers Association (NEMA).

  • Size your motor correctly to increase system productivity
  • Reduce or avoid power factor penalties from your electric utility

Learn more about the new, ultra-efficient electric motors that are now available for purchase in Vermont.

When to Repair vs. Replace

For pre-1990s motors and larger industrial motors, replacement is often more cost-effective than repair or rewinding. We can help you do a cost analysis. Before you replace an underperforming pump, look at its impeller diameter—it can sometimes be adjusted to boost efficiency. Regular cleaning of motor housings and other basic maintenance will also help keep your equipment cool and running efficiently.