Moving Towards Full Renewability: The Potential Impacts of a Renewable Hydrogen Economy on California’s Water Resource

California would be exposing its energy sector to drought risk and locked-in energy losses were it to make major investments in electrolysis-based hydrogen systems. Though a renewable electrolysis-based hydrogen economy could assure dispatchability and energy storage capacity while limiting harmful emissions, many of its benefits are associated with the challenge of patching renewable energy supply into the aging legacy of the current grid system. Faced with the opportunity to redesign energy delivery systems as the grid infrastructure comes to the end of its lifetime, California must recognize that an energy system fundamentally designed around hydrogen rather than electricity as the main energy carrier does not make sense. Not only are significant conversion losses associated with converting electricity into hydrogen and back, but electrolysis demands a substantial amount of very high quality water that is not realistically
available in California. Given California's high growth rate, threatened water supply. ecosystems, and delivery infrastructure, and demonstrated need to use scarce energy as efficiently as possible, the combined problems of high losses and water dependence that a hydrogen economy presents assure that long-term hydrogen-dependent infrastructural investments would be, at best, an inefficient use of resources.