In the drive for efficiency, more businesses are finding savings by rethinking the machines that drive their operations. From the motors along a factory line to air compressors, water pumps and more, using new variable frequency drives (VFDs) offers a range of benefits to businesses – especially in terms of reduced electricity cost and reduced wear on the motors themselves.
These significant advantages over older technology make them a valuable investment for businesses looking to upgrade. But what are VFDs and how do they work?
What is a Variable Frequency Drive?
A variable frequency drive is an electronic device that controls the rotational speed of electric motors by varying the frequency of the electricity supplied. VFDs are commonly used in situations where precise motor control is helpful, such as HVAC systems, pumps, compressed air systems and manufacturing equipment. By adjusting the motor speed to match the specific requirements of the application, VFDs can contribute to energy efficiency savings[1].
Five Ways VFDs Help Businesses Save Energy and Money
- Energy Efficiency: One of the primary benefits of VFDs is improved energy efficiency. Traditional motors often operate at one speed, regardless of demand. They are either on or off. VFDs allow motors to run at variable speeds, matching the load requirements more precisely. By reducing the motor speed during periods of low demand, VFDs can significantly cut down on energy use and deliver better performance.
- Reduced Operating Costs: In addition to the savings realized by lower energy consumption,[2] VFDs can help extend the lifespan of motors and other equipment by preventing the unnecessary wear and tear caused by full-speed operation and frequent stops and starts. This means fewer maintenance and replacement costs over time.
- Improved Process Control: VFDs offer precise control over motor speed and torque, meaning businesses can better optimize their processes. For example, in HVAC systems, VFDs can maintain optimal temperature and airflow, delivering the comfort desired even while reducing energy consumption.
- Enhanced Productivity: By providing better control over motor performance, VFDs can also enhance overall productivity. Businesses can respond faster to changes in demand, easily ramping up or down as needed, which can contribute to smoother operations and improved product quality and availability – all essential to keeping customers happy.
- Access to Rebates: When considering VFD installations, remember that in Minnesota Xcel Energy offers a 25% VFD Bonus Rebate on qualifying equipment to help offset the cost of upgrading. Rebates may be available for HVAC and non-HVAC VFDs, integrated fan energy index and clean water pump VFDs.
Understanding the Implications of VFD Installation
Upgrading to VFDs offers many advantages, but businesses should consider the investment involved. Here are some things to think about:
- Total cost: Retrofitting existing systems with VFDs involves upfront cost. Be sure the savings may offer sufficient return on investment. Additionally, the Xcel Energy rebates mentioned above can partially offset costs, shortening the payback time.
- Finding the right installer: Skilled technicians are required for installation to ensure proper integration and avoid issues such as electrical noise and harmonics, which can affect the performance of other equipment.
- Compatibility issues: Some older HVAC systems might not be designed to handle the variable speeds and could suffer from reduced efficiency or mechanical stress. Be sure to have a professional do a thorough evaluation.
- Downtime costs: Upgrades could potentially disrupt operations, causing inconvenience and lost revenue for a period of time.
Despite these challenges, it’s important to remember that the long-term benefits of energy savings and improved control often outweigh the initial hurdles.