Opportunities and challenges of electrochemical water treatment integrated with renewable energy at the water-energy nexus

Global challenges of reliable energy and clean water presently require concerted approaches in water-energy nexus. Electrochemical methods for water treatment have gathered attraction because of several advantages, such as scalable, modular operations, promising distributed systems, and high energy efficiency. These advantages of electrochemical methods over other water treatment systems make possible to use renewable energy such as photovoltaic solar cells, which might be intermittent in operation but produce enough energy for electrochemical systems. In this communication, we discuss four electrochemical systems (i.e., electrocoagulation, capacitive deionization, electrodialysis, and electrodeionization), powered with photovoltaic systems, for water treatment. We also critically examine the opportunities and challenges in integration of such electrochemical desalination systems with renewable energy for future research in addressing water-energy nexus.