Solar-Thermochemical Hydrogen

Background

Large scale solar-thermal processing of fuels and materials will become a major avenue to offsetting fossil fuel consumption for industrial processes and transportation. The reduction of metal oxides at extremely high temperatures and the subsequent reaction with water to produce hydrogen is a promising way to store the sun's energy with high efficiency and zero emissions. Our project objective is to effect the first step by reducing ZnO into metallic Zn in a novel, semi-continuous, gravity-driven solar-thermochemical reactor.

Project Summary

The University of Delaware has developed a novel solar-thermochemical reactor for the ultra-high temperature creation of solar fuels. This has been possible through a concerted investigation into reactor design, finite element modeling of solar-reactors, vortex flow visualization and CFD, and reactant-feed engineering and characterization. A novel reactor concept has been developed and implemented to the 10kW demonstration level. Thorough modeling has aided the design process, as well as allowed for scale-up analyses of the reactor concept. To ensure a favorable forward reaction pathway and keep the solar-window clear of product vapors, a vortex flow has been developed and thoroughly studied for the two-chamber geometry. Finally, and tantamount to the success of the project, the reactant feed mechanism has been developed to suit the needs of such a gravity-driven, semi-continuous thermal-decomposition reactor.

Key Areas of Research

  • Reactor design
  • Solar reactor modeling
  • Ultra-high temperature reactor engineering and demonstration
  • Vortex flow control, visualization, and characterization
  • Powder reactant handling, feeding, and characterization
Figure 1: Cross section of the beam-down solar thermochemical reactor.
Figure 2: Fabrication process of reactor shell and interior components.
Figure 3: Reactor and vortex flow model, assessing product removal from the reaction surface.
Koepf E.E., Prasad A.K., Advani S.G., "Beam-Down Solar Thermochemical Reactor for the Ultra-High Temperature Dissociation of Solid-Oxides and Creation of Solar Fuels", provisional application filed November 29, 2010.