Abstract
The countries suffer from the freshwater shortage. The solar still is one of the overcoming strategies, however its distillate production is limited. The present work introduces a different arrangement of modifying the pyramid solar still (PSS). This was conducted by changing the flat absorber to a pyramidal absorber to increase the vaporization surface area of distiller. Additionally, several wick materials made of jute cloth and cotton wick were placed over the pyramidal absorber under investigation. Besides, the performance of the modified pyramid solar still (MPSS) was studied when using external condenser and utilizing external mirrors to increase the input solar energy. Finally, a paraffin wax mixed with silver nanoparticles was used as a phase change material (PCM) under the pyramidal absorber of MPSS to be tested. The results revealed that using the modified absorber increased the evaporative surface area of MPSS by around 40%. Also, using the jute cloth material is suggested to be used instead of cotton cloth for the MPSS due to its better operation. Additionally, the best performance of MPSS was obtained with mirrors and condenser, where the productivity improvement and distiller efficiency were 142% and 52.5%.