Experimental studies of a laboratory scale inclined collector solar updraft tower plant with thermal energy storage system

Abstract

In this study, a solar updraft tower (SUT) plant was developed with a thermal energy storage system. It has the chimney height, diameter, inlet gap and absorber plate diameter of 6 m, 0.6 m, 0.1 m and 3.5 m, respectively. A novel canopy-shaped (inclined) collector cover with an inclination of 30° and an in-built TES system that is structurally different from existing studies are the innovation of the study. Experiments were carried out and the data is presented in this work. The study focuses on the time-temperature relationship of ambient air, absorber plate and storage system. Hourly solar flux variation, air velocity, power potential and efficiencies of the system were also investigated. The average temperatures of the collector cover and storage were estimated and these were 45.93 and 42.67 °C, respectively. A maximum air velocity of 2.66 m/s was observed at the chimney base at a maximum solar flux of 938 W/m2. A temperature difference of 25.47 °C was noticed between the absorber plate and air. The maximum theoretical and actual power outputs were 3.45 and 2.3 W, respectively. The overall, chimney and collector efficiencies of the system were estimated and these were 0.02682%, 0.0186% and 44.1%, respectively. Uncertainty analysis was also carried out to verify the reliability of the measured and estimated data. The power potential per collector area for the present SUT plant was 0.239 W/m2 which is 305–505% higher than the similar scale SUT plants.