Architecturally Integrated Reverse Electrodialysis (RED)

Global trends in high-density coastal development in urban zones have eliminated the topographical and ecological transition of the intertidal zone, consequently increasing vulnerability to massive disturbance and disruption related to climate change. The increasing intensity and volatility of climatological and hydrological patterns challenges coastal cities to develop a land-sea interface that absorbs and addresses these unpredictable forces. Despite the vulnerability of urban coastlines, it is unlikely that development in these areas will wane in the near future. Additionally, the widespread failure of large-scale energy infrastructure during large storm events exposes a vital need for site-scale energy production at the coastline. Development in the intertidal zone provides the opportunity for a synthetic architectural-infrastructural system that redirects the hydrologic forces at the shoreline to increase flood protection, restore biological robustness, and produce energy.Current proposals for aquatic energy production are largely focused on flow-based systems. New York State projects that 7 percent of the state’s total renewable energy will be produced by wave energy (0.5 percent), tidal energy (1 percent), and hydroelectric energy (5.5 percent) by 2030 (Jacobson 2013). These proposed technologies are limited by a narrow range of flow characteristics (velocity, frequency and regime) that are largely dependent on the morphology of the surfaces over which they flow. Achieving maximum efficiencies in flow-based technologies requires morphological interventions that enhance high velocity, laminar flow. Although these systems work well in certain landscapes, designing for the acceleration of flow at the coastline is in direct contradiction to the goals of decreased wave energy, biological robustness and flood protection. If sites at the land-sea interface were able to utilize the inherent electrochemical potential where freshwater meets salt water, then surface morphology could enhance conditions for biological and flood protection systems rather than flow-based energy collection.In urban conditions, highly directed water flows off of urban surfaces and through plumbing systems to meet the saline ocean waters at the land-sea interface. The ionic differential between the saline and freshwater can be used to create site-scale energy production using Reverse Electrodialysis [RED] technology. This research explores the feasibility of small scale RED systems utilizing the influx of greywater and stormwater and seawater flows at the coastline. Architecturally integrated RED systems can potentially be deployed in myriad urban coastal morphologies globally to generate electrical energy while reducing wave energy, counteracting negative hydrological forces, and sustaining a reliable energy source during high-energy storm events.The present research reviews the theoretical energy production potentials of large-scale Reverse Electrodialysis, and characterizes the various membrane technologies, water flow and volume requirements, power densities, and cell sizes of current technological iterations. This characterization is then compared with site-scale input and output specifications to validate the feasibility of an architecturally-integrated RED system for localized energy production in coastal areas. Assessing the potential for translation of RED technology across scales allows for an understanding of the energy-production potential and encourages further inquiries into the integration of these systems with inter-scalar architectural surface morphology and coastal hydrological patterns.

Volume Editors
Anthony Abbate, Francis Lyn & Rosemary Kennedy

ISBN
978-0-935502-90-9