Check online to discover your home’s latitude. This is the angle at which you’ll mount your solar panel.
Cut six pieces of plywood for the box. The lid should be slightly larger than the solar panel. Trim the top edges of the side, front, and back pieces to the appropriate angle. Cut the bottom to fit.
Drill a hole in each side panel for airflow: one in the back panel for the controller and battery cords, and one in the lid for the solar panel’s cord. Then nail the wooden slats to the lid and mount the solar panel to it. Assemble the box with a hinge for the lid.