Invisible damage from walking on a solar panel

This video shows that silicon solar cells crack when you walk or kneel on them. Solar cells are easy to break. But when they're packaged in the module, it can be impossible to see this damage. After a cell is cracked, the effect on the solar panel’s power output becomes worse and worse over the years. Temperature changes associated with day and night cause thermal expansions and contractions that help pull apart the materials around the crack. The video is made by running current backwards through the sol