The City of Greeley Water Pollution Control Facility (WPCF) in Greeley, Colorado, has reduced its total energy consumption by 23 percent since 2011, achieving annual energy cost savings of $120,000. The energy efficiency improvements were mainly paid for via the facility’s five-year capital budget plan to take advantage of necessary replacements of aging equipment.
Energy efficiency projects included the replacement of the blowers for the aeration system with high-speed turbo-blowers (pictured), which are 27 percent more efficient than the old blowers, and the installation of LED lights, leading to an annual savings of $100,000 and $7,000 respectively.
Additional energy efficiency projects in the past four years include the replacement of 10 old pump variable frequency drives (VFDs) with new and more efficient ones, upgrades to heating ventilating and air conditioning (HVAC) equipment, and the installation of an energy data management system for the facility’s managers to monitor the plant’s electricity consumption on a daily basis. In addition, a 500 kW solar project saves the facility an additional $7,500 per year (with Greeley’s investment of only $10,000). And in 2015 the facility installed a new sludge dewatering system, which will save an additional $69,000 in energy costs annually.
In December of 2011, Greeley WPCF joined the Colorado Industrial Energy Challenge (CIEC) and set a goal of 20 percent energy savings from 2011 to 2016. The CIEC program is managed by the Southwest Energy Efficiency Project (SWEEP). In May of 2015, the facility earned special recognition from the CIEC program for outstanding energy efficiency achievements and for exceeding its goal, two years early.
Photo credit: Frederica Kolwey