Authors: L. Ferre Llin, S. Thoms, A. Mellor, D. Alonso Alvarez, D. Paul, N. Ekins-Daukes
The electrical performance of photovoltaic (PV) solar cells can be degraded by the thermal radiation these devices are exposed to. For example, the efficiency of a crystalline Si PV cell can be reduced by 0.4% per 1oC.
Therefore there is the necessity to engineer these solar cells to maintain their high efficiency while also take advantage of the extra heat generated by the system.
Hybrid photovoltaic-thermal generators normally use standard PV cells, which are only optimized for electrical photovoltaic performance. We propose a developed PV cell with a nanotextured back surface, and with a selective low emissivity coating at the front surface to reduce heat losses. The nanotextured rear reflector has been designed to increase the absorption near the infrared region of the solar spectrum in order to generate more heat. The loss in electrical efficiency of the thermal-PV will also be evaluated to get to a high efficient system, which compromises electrical and thermal power.