Thermodynamic and economic analysis of heat pump-assisted solar still using paraffin wax as phase change material.

In this research, the thermodynamic (energy and exergy) and economic assessments of heat pump-assisted solar still with paraffin wax was investigated under the climatic conditions of Coimbatore city in India during the year 2020. The observed experimental results in heat pump solar still (HPSS) was compared with conventional solar still (CSS) in the same climatic conditions. This model works on the principle of latent heat observed during condensation which was regenerated by heat pump to preheat the inlet basin saline water of solar still. The observed maximum productivity of HPSS was about 14.5 kg/m2, which was 83.7% higher than CSS. The energy and exergy efficiency improvement in HPSS were about 65% and 82.3%, respectively, higher than CSS. The observed maximum coefficient of performance (COP) of heat pump was about 2.61. The payback period (PBP) of CSS and HPSS was estimated to be about 4.1 months and 3.2 months, respectively. The results observed in HPSS have significantly improved the daily productivity than CSS.