This piece was originally published in the March 2018 issue of electroindustry.
Improvements at the wastewater treatment plant reduced energy use by 30 percent and solid waste by 20 percent. Photo courtesy of Johnson Controls
Evansville, the third largest city in Indiana, is part of a thriving community that serves as the commercial, medical, educational, and cultural hub for the Indiana/Kentucky/Illinois tristate region. To support the mayor’s smart city initiative, the city entered into an energy savings performance contract with Johnson Controls, allowing the city to invest $39 million in much-needed infrastructure without raising taxes.
The improvements started at the wastewater treatment plant and included both traditional and unconventional measures—energy-saving upgrades such as lighting, HVAC, controls, and power factor correction along with valve automation and a solid waste centrifuge—to reduce energy use by 30 percent and solid waste by 20 percent.
By generating power from restaurant commercial kitchen fats, oils, and grease, the process now supplies 40 percent of the energy at the plant. Across the city, a new automated metering system was implemented to increase meter-reading accuracy and efficiency by gathering real-time data from 64,000 meters throughout the city and from 10 wireless towers.
The energy-efficient upgrades will generate an estimated $3.1 million in annual savings over the next 20 years for the city, positioning the Indiana city for future growth.