Solar Cell to USB Charger

cults3d

I started building this at the end of the summer (UK). Because my room gets the sun in the afternoon and evening (3PM+). So at night it becomes very hot and wanted to power a couple of fans. I used 7" (1W) USB fans and even at lower light levels they start to spin, although it needs to be a bright day to have any effect. They can also be folded down and put away if you wish. The sizes of the cells/mini panels are: 12V, 1.5W, 115mm x 85mm, 12V, 3W, 145mm x 145mm and 18V, 3.5W, 165mm x 135mm. The 3.5W size i have not built yet as they have not arrived. The USB adapters can supply up to 3A at 5V. So there are sockets to parallel connect additional assemblies via the 2.1mm DC sockets.if needed. The holes for the bolts are 4mm, 3mm for the single USB socket.