Micro solar energy harvesting using thin film selective absorber coating and thermoelectric generators

The use of a nanometer-scale solar selective absorber coating to enhance the performance of a thermoelectric generation (TEG) module in solar thermal energy harvesting is presented. The thin film coating is fabricated by electrochemical deposition of a bimetallic layer of tin and nickel on copper substrate. The coating has a dendrite structure with grain size of 100 nm. Testing indicates the ability of these collectors to transform incident radiation into thermal energy. The collectors utilizing the selective coating achieved a final temperature 10 °C higher than the baseline copper device. More importantly, the coating demonstrates the ability to collect and transmit over 90 % of the available heat flux. The harvested thermal energy is applied to drive a TEG module for useful power generation. The device utilized with selective absorber coating shows an output power 4.5 times more than the baseline device. Overall area of the collector plate is 16 cm².