I built a solar dryer to dry fruits and meats. I built out of bug screen, a rectangular wooden frame, a sheet of black garbage bag, and a sheet of clear poly. The black absorbed the heat, the screening allowed the contents to dry evenly, and the clear poly kept the bugs out and the heat in. It did fairly well as long as the cuts were thin and there was plenty of sun. I got temps in the 130-150F range and most things were dry after a day. Some wet items took at couple days but if the process wasn't done I'd put a towel over the gizmo and next morning, continue cooking.
Capt. Douglas Abbott
USCG/MCA IV/M.I./C.I. 500-ton Oceans