Water Resource Recovery Facilities Empower the Electrolytic Hydrogen Economy

Environ Sci Technol. 2024 Nov 11. doi: 10.1021/acs.est.4c08054. Online ahead of print.

Abstract

The global transition to net-zero emissions necessitates the integration of clean hydrogen as a key solution. To facilitate the required expansion of clean hydrogen production, sustainable water sources are required to support the electrolysis process. Utilizing nontraditional water sources such as water resource recovery facility (WRRF) effluents could potentially alleviate the water constraints and create cobenefits, but the real-world feasibility has not been explored in depth. Here, we investigated the geospatial interplay between WRRFs and H2 users in a clean hydrogen economy. We developed an optimization framework for contiguous U.S. that would identify H2 users-WRRF pairing through techno-economic constraint and multicriteria decision analysis, and we found that utilizing reclaimed water from WRRFs could save 66% (62-99%) of freshwater for clean hydrogen economy while accumulating $758 (275-1162) million annual national cost savings. The added benefits from H2 users to WRRFs such as pure oxygen aeration would provide a compelling new opportunity for infrastructural symbiosis but warrant a future investigation on its technical and economic feasibilities.

Keywords: clean hydrogen; geospatial optimization; reclaimed water; water electrolysis; water reuse.