Evaporation cooling using a bionic micro porous evaporation system

Abstract

The temperature increase due to incident solar radiation has an adverse impact on the electrical output of photovoltaic (PV) modules. A theoretical model of the fabricated and tested bionic evaporation backside cooling was established and verified by experimental investigation. A micro fluidic structure featuring micro pores consists of two polymer layers attached on the backside of a PV cell model. The thermal performance of roof mounted PV modules with rear panel air ventilation was mathematically described and extended by the cooling capabilities of the developed bionic evaporation foil. The experimental investigations performed in a roof equivalent test environment consisting of a wind tunnel within a climate chamber were in good accordance to the established model. Experimentally temperature reductions at low incident solar power of less than 575W causing an efficiency gain for up to 4:8% have been demonstrated while the model implicates an efficiency increase of 10% for real roof systems at an incident solar radiation of 1000W.