Energy Usage and Management at a Large Wastewater Treatment Facility in Boulder, Colorado

Abstract

Wastewater treatment plants require substantial amounts of energy for pumping and treating water as well as for other plant operations. National and regional policy changes resulting in stricter water quality standards could result in an increase in energy requirements for treatment, as further treatment or more energy intensive technologies would be required. Given rises in energy costs, effective energy management plans are necessary for municipal wastewater treatment plants. Energy usage in wastewater treatment plants can be reduced through a number of different technology options without compromising water quality output. These different technology options vary in effectiveness, energy intensity, and upfront and operational costs, and the choice of technologies is often dependent upon local conditions and plant specific characteristics. Energy management can be improved also through electricity production on-site from the capture of methane gases released during treatment or from the inclusion of renewable electricity generating technologies. These technology options augment the creation of energy on-site while not necessarily reducing total energy demands. The objective of this paper is to, through use of a case study of a wastewater treatment facility in Boulder, Colorado, describe the most energy intensive processes of wastewater treatment, review various technology options for these processes, and discuss the opportunities and barriers to improving energy management at wastewater treatment plants. This paper is part of a topical session entitled “An Energy Appetite of U.S. Water Systems — what does it take to supply our water?”