Philipp Furler, ETH Zurich, Switzerland
Nature of the work & Objectives
Task II addresses the demonstration, scale-up, and market penetration of solar-driven thermochemical processes for the production of fuels (e.g. hydrogen, syngas, methanol, kerosene, diesel) and materials (e.g. metals – Zn, Al, Fe) or high-temperature energy storage.
Status of the Technology
Solar thermochemical processes offer efficient pathways for the conversion of carbonaceous feedstocks, minerals or pure water and carbon-dioxide into fuels and valuable materials with significantly lower greenhouse gas emissions compared to conventional processes. Concentrated solar radiation serves thereby as clean high-temperature process heat to drive the chemical reactions.
At present, solar thermochemical processes are at R&D state and not commercially implemented yet. Solar hybrid technologies, which combine solar energy with a carbonaceous feedstock to form a partially renewable fuel, are closest to maturity. First pilot-scale plants (up to 500 kWth) have been built and successfully tested. Whilst these solar-fossil hybrid technologies still cause significant greenhouse gas emissions, they should be regarded as transitional for the near-to medium-term future and will provide a valuable learning for the long-term carbon-neutral H2O/CO2 splitting technologies. Those technologies will need more time to become economical as the technical complexity is higher. Nevertheless, substantial progress was achieved for the clean processes over the last years, for example in the framework of the EU-funded research project SolarJET, the entire production chain to clean jet fuel (kerosene) via thermochemical splitting of water and carbon-dioxide was demonstrated and world record energy conversion efficiencies above 5% (solar-to-H2/CO) have been achieved. Besides fundamental research at small scale, some projects are far beyond laboratory-scale. For instance, within the EU-funded project Hydrosol, a 100 kWth solar-chemical hydrogen pilot-facility is under construction at the Plataforma Solar de Almeria in Spain or in the Sun-to-Liquid project (http://www.sun-to-liquid.eu), kerosene and diesel production from water and carbon-dioxide will be demonstrated at the 50 kWth scale on a small tower system at IMDEA Energia near Madrid.
Published Task Reports
Organization and Structure
The operating agent is responsible for organization and reporting of Task II activities. National Coordinators are reporting the individual country activities to the operating agent and enable local contacts for international collaborations between R&D institutions and Industry. Appointed Topic Experts are in charge of reporting the status of the core technology routes and are coordinating sub-task activities.