According to the DOE in most industries, centrifugal pumps are identified as the largest consumers of electric motor energy. Also, among all rotating assets in the plant, process pumps had the highest overall potential for electrical energy savings. It was also identified in pumping systems; the electric motor is often oversized during the design phase by an average of 20%. When you consider that every watt of power wasted by over-sized or over-throttled pumps becomes a destructive force that lowers overall process reliability; optimizing pump performance is the key to achieving a triple benefit—lower energy consumption, lower maintenance costs and improved process control.
The higher the pump horsepower (greater than 15- to 30-hp), the more cost-effective the ASD application. Centrifugal loads with variable-torque requirements (such as centrifugal pumps or fans) have the greatest potential for energy savings. ASDs can be cost-effective on positive displacement pumps, but the savings will generally not be as great as with centrifugal loads.