Chlorophyll strikes a photon of light, allowing an electron to be energized. the electron transport chain, the free electron passes, and the electron's energy is used to inject hydrogen ions into the thylakoid space, transferring the energy to the electrochemical gradient.
I think the best explanation to this is that plants will do everything to get sunlight thats why they move in order to get more. I hope you are satisfied with my answer and feel free to ask for more if you have questions and clarifications