Comparative Study of Single Pass Collector and Double Pass Solar Collector Filled with Porous Media

This research reports a comparative study of the conventional single pass flat plate collector and the double pass solar collector filled with porous media such as gravel and metal chips at the lower channel of absorbing unit. The component materials, design, performance efficiencies, capabilities and the application of the solar collectors are presented to show various disparities that exist between the collectors. Emphasis was laid on the multi-pass approach as a gate way to future development on solar collectors.