Grand Challenges in Salinity Gradient Energy Generation

Document Type : Grand Challenges


1 Atılım University, Turkey

2 Ege University


Reverse electrodialysis (RED) generates energy from salinity gradients, such as the one between seawater and river water, by selectively transporting ions through ion-exchange membranes. This paper discusses the challenges facing RED in four areas: ion exchange membranes, stacks, fouling, and processes, although it may not cover all issues as new advancements arise. Although bench-scale RED has impressive power generation, pilot-scale RED operations present challenges for widespread adoption. However, the main advantage of RED lies in its potential for synergetic applications with other processes like energy conversion/storage, wastewater treatment, and desalination. The development of low-cost, innovative membranes and integration processes with high energy efficiency and power generation capabilities for both scaled-up and-down approaches is essential for RED's continued advancement. Dedicated research will contribute to its potential for integration with other processes and viability as a renewable energy source. RED has the potential to be a significant player in the renewable energy market, but new advancements also present new challenges.

Graphical Abstract

Grand Challenges in Salinity Gradient Energy Generation


Ø The main challenges of reverse electrodialysis discussed.

Ø New advancements rise to new challenges.

Ø Membrane fabrication at low cost is crucial.

Ø Hybrid process integration is to continue.



Main Subjects

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