Submitted by: Laboratory Paul Scherrer Institute
Implemented country: Switzerland
Title: Storing Solar Energy in Zinc
In the framework of the EU research project SolZinc, an innovative pilot plant was realized for marketing the use of concentrated solar energy: about 300 kW of concentrated solar power is utilized to produce zinc from ZnO with the aid of a small amount of charcoal at temperatures of 1100-1200 °C, yielding 50 kg/h Zn dust of 95% purity. Based on the pilot experience, a conceptual design of a solar Zn demonstration plant at a power level of 5 MW and an economic assessment of the solar carbo-thermal ZnO/Zn process are being performed to pave the way for the further development of the SolZinc technology. Options for processing the solar zinc with steam to produce high-purity hydrogen and the use of the solar zinc as a fuel for zinc-air batteries and fuel cells are being evaluated as well. In either case, the chemical product is ZnO, which in turn is solar-recycled back to Zn, closing the thermo-chemical ZnO/Zn cycle.