Integrated microscale cooling for concentrator solar cells

The work presents a new solution proposal to the cooling of concentrator photovoltaic cells. In our concept the microscale channels are integrated into the back surface metallization, the microscale channels are formed by electroplating copper around a photoresist channel pattern. This approach has the advantage that it has no restrictions regarding the solar cell material and technology. In this work we give a description on the process technology, perform mechanical simulations for the feasibility of our approach, optimize the channel geometry for a 20 × 20 mm concentrator solar cell and estimate the cooling performance of the microscale channel structure at different operating conditions. We found, that the proposed cooling solution would have a calculated thermal resistance of 0.26 K/W at pressure drop of 100 kPa. This would result in a temperature raise of less than 8 K in case of a concentration level of 100 suns and a solar cell efficiency of 25 %.