This presentation will focus on the use of ultra-high temperature transport tube reactors for producing non-oxide ceramic powders and fuel intermediates. In both cases, reactors operate between about 1000 and 2000 C. The process to produce non-oxide carbides using resistive heating has been commercial for over 10 years. The process using concentrated sunlight to produce reduced metal oxides for water splitting thermochemical cycles and to convert biomass to sygnas will be commercialized sometime in the not too distant future. Discussion will focus on the key attributes of the reactors for both processes, including the challenges overcome to commercialize the ceramic powder process and the challenges that need to be overcome for the solar-thermal reactors to be commercial.