Water Sector Energy Efficiency through an Integrated Energy Management System

California water agencies account for 5.1 percent of the state’s electricity consumption. The systems these agencies use for pumping and treating both fresh and wastewater use equipment of varying ages, from a variety of vendors. This equipment is not controlled as a coherent system to minimize electrical demand. In this project, researchers from University of California, Riverside, built data analysis systems using data acquisition components made by Opto 22, and historian software from OSIsoft. The researchers developed software to display and analyze energy use for three water agencies in Southern California. The goal was to minimize total electric energy and demand cost, based on time-of-use or real-time electric rates. The software provides timely information to operators to guide their operational decisions towards reducing electric demand charges. In the Cucamonga Valley Water District, with an average monthly peak use of 1.18 megawatts, the system guided operators to a demand charge reduction of 41 percent, yielding more than $100,000 of facility-related demand charges and more than $40,000 of time-related demand charges. A proportional reduction across all of California’s water agencies, with a total demand of around 3,000 megawatts, could yield statewide savings of more than $31 million, in addition to reduced air pollution and other environmental and economic benefits.