Bipolar membrane Electrodialysis enables extracting economically valuable products from clean brine, thus forming a crucial component of the circular economy. We have performed a detailed techno-economic assessment (TEA) on generating sodium hydroxide from brine using the WaterTAP framework. The cost optimal results are reported over a large parameter space. Under power constraints on the stack, we find high inlet salt concentration does not necessarily reduce costs or raise NaOH concentration. Our detail analysis resolves the important roles of water disassociation, limiting currents, and sodium diffusion in sculpting the levelized cost landscape. We show water splitting dominates the TEA for most cases. Our sensitivity analysis reveals cost associated with bipolar membrane properties controlling hydrolysis being comparable to unit cost. Our results suggest targeting water disassociation should be prioritised for reducing levelized cost of producing sodium hydroxide.
