Energy and water quality management systems for water utility's operations: A review

• EWQMS is an optimization framework solving energy and water quality problems.
• This work provides the state-of-knowledge on EWQMS in drinking water utilities.
• An EWQMS allows the implementation of energy cost reduction strategies.

Holistic management of water and energy resources is critical for water utilities facing increasing energy prices, water supply shortage and stringent regulatory requirements. In the early 1990s, the concept of an integrated Energy and Water Quality Management System (EWQMS) was developed as an operational optimization framework for solving water quality, water supply and energy management problems simultaneously. Approximately twenty water utilities have implemented an EWQMS by interfacing commercial or in–house software optimization programs with existing control systems. For utilities with an installed EWQMS, operating cost savings of 8–15% have been reported due to higher use of cheaper tariff periods and better operating efficiencies, resulting in the reduction in energy consumption of ∼6–9%. This review provides the current state-of-knowledge on EWQMS typical structural features and operational strategies and benefits and drawbacks are analyzed. The review also highlights the challenges encountered during installation and implementation of EWQMS and identifies the knowledge gaps that should motivate new research efforts.