Source google image: https://www.picclickimg.com/d/l400/pict/312341703734_/Parasol-Pour-Jardin-3X3-D%C3%A9centralis%C3%A9e-Avec-Le-Panneau.jpg
Panneau solaire equation
Source google image: https://www.picclickimg.com/d/l400/pict/312341703734_/Parasol-Pour-Jardin-3X3-D%C3%A9centralis%C3%A9e-Avec-Le-Panneau.jpg