(Invited) An Overview of the U.S. Department of Energy's Consortia Focused on Enabling Low-Cost Hydrogen Production Via Water Splitting Technologies

Abstract

Hydrogen provides a unique opportunity for affordable, reliable, clean, and secure energy across sectors, many of which can be hard to decarbonize. To enable low-cost and sustainable hydrogen production at scale, the U.S. Department of Energy’s Hydrogen and Fuel Cell Technologies Office (HFTO) supports RD&D to address critical challenges and barriers across a broad portfolio of hydrogen production technologies. One very promising pathway for large-scale hydrogen production is water splitting.Water splitting technologies range from commercial technologies such as electrolyzers, which are currently manufactured at the MW scale, to approaches that are at a much earlier stage of development, such as photoelectrochemical (PEC) and solar thermochemical (STCH) processes. All these water splitting pathways offer diverse benefits in energy storage, grid services, and cross-sector emissions reductions while taking advantage of our abundant renewable, nuclear, or fossil energy resources. However, as with most innovative and potentially high-impact clean energy technologies, critical materials-, component- and system-level challenges must be addressed to improve efficiency and durability, as well as reduce cost. As such, HFTO initiated the HydroGEN Advanced Water Splitting Materials (AWSM) Consortium in 2017 and recently launched the H2 from the Next-generation of Electrolyzers of Water (H2NEW) consortium.HydroGEN (https://www.h2awsm.org/), one of DOE’s 7 Energy Materials Network (EMN) consortia is dedicated to accelerating the materials R&D of low TRL advanced water splitting (AWS) technologies, is now in its second phase. The consortium comprises five core national laboratories and focuses on four early stage AWS pathways: alkaline exchange membrane (AEM) electrolysis, proton conducting high temperature electrolysis, photoelectrochemical, and solar thermochemical water splitting. Providing streamlined access to world-class expertise and experimental and computational capabilities, the consortium is currently supporting 23 university, industry and national laboratory R&D projects seeking to discover and design new materials to increase efficiency and durability of water-splitting systems. In addition, HydroGEN has recently initiated consortium-led efforts focused on the most critical barriers to these AWS pathways.With PEM electrolyzers already commercial and significant advancements in oxygen conducting solid oxide electrolysis cells (O-SOECs) realized, the critical R&D needs for these technologies are no longer at the foundational, materials development level. Yet these systems are still too expensive for wide-scale commercialization. To enable high-volume manufacturing of affordable, durable, efficient electrolyzers, H2NEW, another multi-lab consortium, was established in 2020. This comprehensive, concerted effort is focused on overcoming barriers related to components and materials integration, with an initial focus on durability, to achieve <$2/kg H2.