See: https://en.wikipedia.org/wiki/Shockley%E2%80%93Queisser_limit

Conventional solar panels that are made of silicon wafers have low conversion efficiency (solar radiation to electricity) due to the diminishing reliability of the wafer technology over time. Also, these silicon wafers have limited absorptivity of the incident solar radiation.

The newer technology called thin-film solar PV, have higher conversion efficiency closed to 40% but they are more expensive and less mature technology compared to the conventional solar PV (wafer-based) technology.

Hope this helps answer your question.

I teach this topic in my summer course at Yale University.

Khalil, Y.F. (Summer 2016). Green energy systems. Lecture notes, S105E, Yale College, New Haven, CT 06520, USA

Professor Yehia Khalil

Yale University

USA

Dear Maharaja,

The most important parameter that can influence the electrical efficiency of a PV module is the temperature of the PV cells. when the temperature of the PV module increases the conversion efficiency will decrease.

 I hope that the following paper will help you understand how the Temperature of a PV module may affect the conversion efficiency.

Article Study and modeling of energy performance of a hybrid photovo...