VSD Saves Energy in Chilled Water System
The College of the Desert in Palm Desert is reducing electrical usage, electric demand, and lowering operating costs. With assistance from Southern California Edison, the college installed an energy-efficient variable speed drive (VSD) at the campus chiller plant.
Conventional chilled water plants distribute water at a constant flow rate, regardless of the actual cooling demand. Since most air conditioning systems only reach peak load a few hours a year, energy is wasted by continually running the pumps at a constant speed.
Substantial energy savings can be achieved by matching the flow rate to the system's cooling needs. The College of the Desert is realizing an annual energy savings of 276,500 kWh with a total utility savings of $28,860 and a 2.8-year payback period for the VSD.