Energy Analysis of Wastewater Infrastructure

Abstract

Urban wastewater systems (WWS) comprising of municipal sewage collection, treatment, and disposal play a vital role in alleviating urban water pollution and maintaining overall public health and sanitation. WWS forms one of the most energy-intensive components of the urban water cycle and requires huge financial investment for its construction, operations, and management. The financial burden of WWS operations can be subsided to a significant extent by implementing strategies for energy reduction, optimization as well as energy production and recovery from wastewater. However, developing an energy-neutral or energy-positive WWS is a challenging task, requiring the application of several interdependent energy pathways. In this chapter, comprehensive energy analysis of WWS is carried out, considering the available routes for reducing, optimizing, producing, and recovering energy from wastewater. Alongside this, available approaches for assessing the total energy consumption and energy efficiency of the WWS have also been evaluated. The use of indicators and indices can be particularly effective to both quantify and compare energy efficiency within different components of a WWS or among different WWS. The diagnostic potential of energy efficiency indices (EEIs) proposed specifically for WWS has been comparatively evaluated in this study. Such an index-based energy evaluation can conveniently characterize the energy efficiency of WWS and facilitating energy benchmarking of systems.KeywordsMunicipal wastewaterEnergy recoveryEnergy efficiency indicesEnergy benchmarkingEnergy self-sufficiency