Solar Cell Basics

labideal February 9, 2020 86

This is how a solar cell works. The silicon wafer has an electron rich (n) layer and an electron poor (p or hole) layer. A photon of light energy is absorbed by the silicon semiconductor and if it has sufficient energy it forms an electron/hole pair or exciton. Under the right conditions the charges are separated and the free electron flows through the circuit creating an potential. Meanwhile another electron flows from the circuit back into the hole layer where it recombines with the original hole that was created.

“Providing clean energy to the inhabitants of our planet is a major challenge to future generations. The University of Washington is to be congratulated for establishing an Institute where faculty and students can work together to tackle the difficult global challenge of energy sustainability.”

– Mildred Dresselhaus, Professor of Physics and Electrical Engineering, Emerita and Institute Professor, Massachusetts Institute of Technology