A review of high temperature solar driven reactor technology: 25 years of experience in research and development at the Paul Scherrer Institute

Abstract

High temperature fuel production and thermal material processing driven by concentrated solar energy has the potential to significantly reduce the fossil fuel dependence of our current energy economy. Critically important to the utilization of solar power to drive a high temperature thermal or thermochemical process is the solar receiver and reactor. In this review article, the full scope of the development process for a solar receiver and reactor is considered, beginning with fundamental materials science and ending with large scale demonstration projects. As representative examples, and spanning over 25years of solar reactor research and development by the Solar Technology Laboratory at the Paul Scherrer Institute, five projects have been selected and are presented in detail: H2O and CO2 splitting via the Zn/ZnO thermochemical cycle brought to the 100kW level, carbothermal reduction of ZnO demonstrated at the 300kW level, gasification of carbonaceous waste materials proven at the 150kW level, H2O and CO2 splitting utilizing non-stoichiometric ceria, and the production of industrial grade lime. These projects represent significant efforts which bridged the gaps between science, technology, engineering, and demonstration for solar-driven high-temperature receivers and reactors. Additional relevant solar reactor development projects from around the world are summarized and compared. Given the simultaneous demand for carbon-neutral energy vectors and liquid hydrocarbon fuels, combined with the significant technological progress achieved with solar reactors, industrial-scale implementation of solar-driven fuel production and high temperature materials processing is likely to expand significantly within the next decade.