Reverse electrodialysis heat engine with multi-effect distillation: Exergy analysis and perspectives

•An exergy analysis of a reverse electrodialysis heat engine is presented for the first time.•Irreversibility sources of the system are identified and quantified.•The effect of the main operating variables on the exergy efficiency is assessed.•High-performing membranes in reverse electrodialysis dramatically improve the overall performance.•A maximum exergy efficiency of 24% has been reached.