Review of energy management guidance for water and wastewater utilities

Water and wastewater utilities consume significant energy, and much guidance has emerged especially in the past 25 years to help them manage it. The confluence of literature from independent groups in the same timespan speaks to the enduring relevance, technical nuance, and deep substance of the topic. At an important time in the energy–water nexus, we critically review 29 key publications that provide comprehensive guidance on the subject. We categorize the recommended practices, explore the origins of the guidance, discuss commonalities and differences in the recommendations, reflect on the evolution of the guidance, and suggest directions for future developments. From this novel review, we find that while the documents’ scopes and origins differ, consensus has developed around several core capital, operational, and managerial practices that the water and energy industries have accepted. These include upgrading pumping equipment, installing renewable energy, upgrading treatment equipment, repairing leaky pipes, operating according to power rate schedules, optimizing pump use, optimizing treatment processes, performing regular maintenance, performing energy audits, engaging in outreach, training an energy team, and setting goals. Many of the practices are supported by over 260 case studies in the documents. Some practices are experimental and need more work. Even as the ongoing transition to cleaner energy is necessitating new approaches that water and wastewater utilities must embrace, the diversity of practices testifies to multiple successful paths to energy management. We recommend that water and wastewater utilities choose options that best suit their opportunities, capabilities, and values.