Experimental investigation of pistachio shell powder (bio-waste) to augment the performance of tubular solar still: Energy, exergy, and environmental analysis

Abstract

In this current investigation, we examined the impact of incorporating water, kept in the basin, with pistachio shell powder as a thermal repository material, to enhance water harvesting. The study involved a comprehensive analysis of energy, exergy, and environmental factors for both systems. Two types of tubular solar stills were constructed—one integrating pistachio shells powder, which has been reduced to 1.5 mm average size of the particle using a grinding machine, as sensible energy storage materials, and the other following a conventional tubular design. The findings revealed that the use of pistachio shell powder as an energy storage material significantly improved water production by 46.26 % compared to the conventional tubular solar still (CTSS). The water productivity for the modified tubular solar still (MTSS) reached 2.7 kg, while for CTSS, it was 1.9 kg. The thermal and exergy efficiencies were also calculated, with values of 22.36 % and 1.98 % for the pistachio solar still, and 16.86 % and 1.35 % for the conventional system, respectively. Additionally, the net payback period for both systems was assessed, resulting in 0.479 years for the MTSS and 0.636 years for the CTSS.