(469b) Solarthermal Chemistry – the Path Forward

Authors: 
Weimer, A. W., University of Colorado Boulder
CSP/PV hybrid farms provide the path forward for large scale solarthermal chemical processing. PV electricity is lower cost compared to CSP as a result of distributed growth that has provided manufacturers and installers valuable experience leading to rapid cost cutting. However, PV canâ??t match CSP in terms of cheap storage. PV can be used to supply parasitic electricity needs on-sun, while CSP can be used for supplying electricity whenever a cloud passes over, as well as into the evening. Directly driving the solarthermal reaction with concentrated sunlight using a hybrid solarthermal/electrical receiver is most efficient since there is no loss in efficiency converting sunlight to electricity. The â??sweet spotâ? for such solarthermal heating is processes operating where fast radiative heating drives the processing and provides for fast chemical reaction kinetics. Hybrid solarthermal/renewable electricity driven reactors are required in order to provide for viable non-intermittent chemical processing. Further, although the overall objective is a totally renewable process to fuels and chemicals, most likely some fossil feedstocks will provide for a path forward. Considerations also need to be made concerning the availability of suitable sunlight and the proximity of required feedstocks. A number of processing challenges need addressed: (1) design of hybrid solarthermal/electric chemical reactors, (2) process control for bumpless transfer between concentrated solar heating and PV/CSP provided electrical resistance heating, (3) improved methods for thermal storage, and (4) process development for appropriate chemical processes, among other challenges. This presentation will attempt to provide for a framework for a path forward using concentrated sunlight and renewable electricity to drive chemical processing. Some example opportunities will be discussed.