Experimental Evaluation of a Hybrid Inclined Solar Chimney for Power Generation

Abstract

The intermittent nature of solar energy is a problem for power demand-supply. In particular, power generation by a solar chimney is insufficient due to low efficiency and interrupted power production. In the current research, an experimental model of an inclined solar chimney is integrated with an external heat source to develop a hybrid solar chimney. The developed hybrid solar chimney utilizes the exhaust flue gas from a lab-scale experimental gas turbine. The exhaust gases from the gas turbine were supplied through a passage underneath the absorber plate of the solar chimney. The absorber plate is modified into a heat exchanger by adding extended surfaces in the flue passage. Furthermore, the hybrid system is experimented outdoors to utilize solar irradiation, and a burner produces the hot gases. Experimental measurements have been carried out in three different cases. The investigated system performance to produce power is enhanced by 91.0% by integrating the inclined solar chimney with an external heat source at an average temperature of only 88.0℃. The results show that the mean enhancement in the air temperature rise of the hybrid mode is 33% compared to the solar mode; this considerably improves the solar chimney performance. The proved concept of the hybrid inclined solar chimney could be adopted in existing thermal power plants to recover the heat losses in the flue gases.