A metal oxide reduction solar reactor is developed to operate in vacuum. Thermal and structural analyses of the system supported the design. Two calculation packages were used for the thermal analysis and another one was applied for stress analysis of the quartz window. Experiment in an empty, inert system was carried during the initial testing steps and used for the simulations validation. The models predictive capabilities were established, and can be now safely used in further improving and extending the design. (C) 2013 Elsevier Ltd. All rights reserved.