“EVALUATING OPPORTUNITIES AND BARRIERS TO IMPROVING THE ENERGY EFFICIENCY OF SMALL NEBRASKA WASTEWATER TREATMENT PLANTS”

Advisor: Dr. Bruce Dvorak

Wastewater treatment plants (WWTP)s account for about 30.2 terawatt hours or 0.8% of U.S. electricity use. Small community wastewater treatment plants (WWTP)s serving communities with populations less than 10,000 make up over 95% of the treatment plants in Nebraska. These WWTPs can account for a significant portion of a municipality’s energy usage and are significantly less efficient compared to large systems, thus improving energy efficiency (E2) of these systems has been a growing focus of technical assistance providers in efforts to reduce greenhouse gas emissions associated with their operation.

Energy use of plant unit operations was evaluated for several plants and included analysis of energy used for space heating at plants. The potential for improving E2 of these plants was evaluated by quantifying the annual billed energy use reduction of plants making specific infrastructure and/or operational changes reported by operators following a previous E2 benchmarking project conducted across the state. Barriers to implementation of E2 improvements at WWTPs had been investigated through a two-page survey of operators and the results were supplemented with discussions had with operators and observations from plant assessments occurring throughout the benchmarking project and fifteen subsequent energy assessments.