Fabrication of parabolic trough hybrid solar PV-T collector using a-Si thin film solar cells in Indian perspective

Abstract

Indian economy is growing rapidly but the population of the country (1.2 billion approx.) are also increasing and facing massive energy and pollution problems. Solar energy is the most desirable renewable energy resource to fight with the energy and pollution problem in the country simultaneously. There are new emerging solar technologies like Concentrated Solar Power (CSP) and hybrid technologies. Hybrid solar Photovoltaic-Thermal (PV-T) collector of parabolic trough using a-Si thin film solar cells is designed for Indian market. The system consists a parabolic trough to concentrate sunlight towards a CPC containing a-Si solar cells. The parabolic concentrator is used to generate electricity as it contains a-Si solar cells but is also used to further concentrate sunlight towards thermal collector. Most of the high-energy photons present in sunlight is absorbed by a-Si solar cells and converted into electricity and remaining energy photons reflected and concentrated towards thermal collector, thus exergy output of the system and utilization factor of the solar radiation is increased. The concentration takes place at two stages which enable us to reach higher temperatures at thermal collector. This design has potential to generate electricity as well as thermal energy at the same time. This thermal energy can be further used in electricity generation or other desirable purposes. Amorphous Si solar cells are easily available in Indian market at affordable prices unlike other thin film solar cells. A-Si Cells are used in PV-T hybrid system because of their availability in India market and their sustainability at higher working temperatures. The electrical efficiency measured from the device is 14.93% and average thermal temperature difference at thermal collector measured is 11.40F.