Exergy performance evaluation of a basin-type double-slope solar still equipped with phase-change material and PV/T collector

• Published in: Renewable energy 2020-01, Vol.145, p.2409-2425
• Main Authors: Hedayati-Mehdiabadi, Erfan, Sarhaddi, Faramarz, Sobhnamayan, Fatemeh
• Format: Article
• Language: English
• Subjects: Basin-type double-slope solar still; Exergy analysis; Phase-change material; PV/T collector
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2019.07.160

This study investigated the exergy performance of a basin-type double-slope solar still equipped with phase-change material (PCM) and PV/T collector. PV/T collectors improve fresh water production during the sunshine hours of the day by pre-heating the saline water, and utilization of PCM makes it possible to produce fresh water at night. The governing equations were obtained by writing energy and exergy balances for solar still components. The numerical results in this study were well fitted into the experimental data. System performance was investigated with respect to fresh water production and exergy efficiency for sample winter and summer days in Zahedan, Iran. Results showed that the fresh water productivity increased by 10.6%, and the exergy efficiency improved by 27% and 2% on 6 July and 23 December, respectively, when mass flow rate increased from 0.001 to 0.01 kg/s. By increasing the saline water mass from 20 to 30 kg, the fresh water production was reduced by about 4.8% during the day, but increased by about 7.43% during the night. Exergy efficiency was 45% lower on the winter day than on the summer day. The highest electric power generation values on 6 July and 23 December were 120 and 50 W, respectively. In this paper, the exergy analysis of a basin-type double-slope solar still equipped with PCM and PV/T collector is investigated, theoretically. The effect of various design and operating parameters on the freshwater productivity, output electric power and irreversibility rates is studied. [Display omitted] •Exergy analysis of a basin-type double-slope solar sill is carried out.•Basin-type double-slope sill is equipped to PV/T collector and PCM.•Daily fresh water production of the solar sill is 6.5 kg/m2.h.•Desirable value of mass flow rate is obtained 0.01 kg/s.