Photovoltaic technology has emerged as a viable renewable energy source and new solar farms are being constructed all over the world. The underlying cell technology (e.g., single junction Si solar cells), however,  is 50 years old and rapidly approaching its efficiency limit. Further improvement in PV efficiency is possible through multi-junction solar cells, and recent breakthroughs in the performance and reliability of perovskite-Si tandem cells promise a new generation of solar farms based on tandem cell technology.  

 In this talk, I will use thermodynamic arguments, and device/module physics, coupled with farm topologies to explain the opportunities and challenges of renewable energies in countries such as Saudi Arabia.  I will explain how a fundamental rethinking of test and qualification methodologies is needed to experimentally validate the potential of traditional and tandem solar cell technology in field conditions.