Experimental results for a MW-scale fluidized particle-in-tube solar receiver in its first test campaign

•A 40-tube fluidized particle-in-tube solar receiver is tested.•Aperture solar power reaches 800 kW.•Particle mass flow rate ranges from 2.15 to 12.5 tons/h.•Thermal efficiency of the solar receiver ranges from 35 to 63%.•Particle flow in the tubes is very sensible to the solar flux distribution. To advance the development of particle-driven technologies, this study presents experimental results of a megawatt-scale solar receiver installed atop the Themis Solar Tower (France). The whole experimental loop and the solar flux distribution at the receiver aperture are described with the associated instrumentation. The solar receiver is composed of forty 4-meter long metallic tubes, and the irradiated part size is 3 m high and 2.6 m wide. The facility was operated at partial load with a maximum solar power of approximately 800 kW with a particle mass flow rate ranging from 2148 kg/h to 12456 kg/h. The tube wall temperature distribution is presented along with a particle temperature increase that reached 400 °C. The dynamic behavior of the solar loop is detailed, in particular the starting phase. The thermal efficiency of the solar receiver ranges from 35 to 63%. An assessment of the lessons learned during this experimental campaign is offered.