Electrodialytic Energy Storage System: Permselectivity, Stack Measurements and Life-Cycle Analysis

Abstract

Reverse electrodialysis and electrodialysis can be combined into a closed energy storage system, allowing for storing surplus energy through a salinity difference between two solutions. A closed system benefits from simple temperature control, the ability to use higher salt concentrations and mitigation of membrane fouling. In this work, the permselectivity of two membranes from Fumatech, FAS-50 and FKS-50, is found to be ranging from 0.7 to 0.5 and from 0.8 to 0.7 respectively. The maximum unit cell open-circuit voltage was measured to be 115 ± 9 mV and 118 ± 8 mV at 25 • C and 40 • C, respectively, and the power density was found to be 1.5 ± 0.2 W m -2 uc at 25 • C and 2.0 ± 0.3 W m -2 uc at 40 • C. Given a lifetime of 10 years, three hours of operation per day and 3% downtime, the membrane price can be 2.5 ± 0.3 $ m −2 and 1.4 ± 0.2 $ m −2 to match the energy price in the EU and the USA, respectively. A life-cycle analysis was conducted for a storage capacity of 1 GWh and 2 h of discharging. The global warming impact is 4.53·10 5 kg CO 2 equivalents/MWh and the cumulative energy demand is 1.61·10 3 MWh/MWh, which are 30% and 2 times higher than a lithium-ion battery pack with equivalent capacity, respectively. An electrodialytic energy storage system reaches a comparable global warming impact and a lower cumulative energy demand than a lithium-ion battery for an average life span of 20 and 3 years, respectively.

Electrodialytic Processes: Market Overview, Membrane Phenomena, Recent Developments and Sustainable Strategies

“…An alternative configuration consists in implementing “upstream” RED associated with ED or other desalination technologies in order to readily supply power from RED to ED [ 304 ]. Recently, a salinity gradient energy storage system (SGESS) was investigated [ 305 ]. The two-step process combined a RED phase (discharging) producing energy from streams of different salinities, followed by an ED phase (charging) to regenerate the initial streams at higher salinity than natural streams.…”

Electrodialysis Applications in Wastewater Treatment for Environmental Protection and Resources Recovery: A Systematic Review on Progress and Perspectives

“…Please note that studies on similar or hybrid processes have been growing, i.e., EDI with configurations deviating from conventional ED stacks (important role of electrode chambers) [ 42 , 45 , 46 , 47 , 183 ], RED and fuel cell (Fenton)-RED with wastewater treatment at the electrode compartments [ 53 , 57 , 544 , 545 , 546 , 547 ], concentration gradient or pH gradient flow batteries [ 548 , 549 , 550 ], membrane electrolysis and electro-electrodialysis [ 551 , 552 , 553 , 554 , 555 , 556 , 557 , 558 , 559 , 560 ], hybrid liquid membrane-ED [ 561 , 562 , 563 ], decoupled ED [ 564 ], shock ED [ 565 ], (membrane) capacitive deionisation [ 566 , 567 , 568 , 569 , 570 , 571 , 572 , 573 , 574 ], membrane electrode redox transistor ED [ 575 ], bio-electrochemical systems [ 576 , 577 , 578 , 579 ] including microbial desalination cell [ 580 , 581 , 582 , 583 ], microbial desalination and chem...…”

The Influence of Concentration and Temperature on the Membrane Resistance of Ion Exchange Membranes and the Levelised Cost of Hydrogen from Reverse Electrodialysis with Ammonium Bicarbonate

“…The cost of heating is assumed to be 0.005 € kWh [ 26 ]. We assume for the pilot scale, that the material development will lead to cheaper and less resistive membranes, i.e., SPEEK or carbon-based membranes, and that for the commercial scale these membranes will be produced at large scale (60 × 10 m per year) and reduced thickness (25 m and maintaining the mechanical strength) which will in turn reduce the cost and resistance further [ 26 , 31 , 32 ].…”