:smack:
I don’t know if it outputs enough voltage, but if you can get your hands on one, Nivea had a print ad that was actually a solar charger that you could charge your phone with.
Since it’s a fan with a usb input you want to power, going directly from solar to USB without going to rechargeable batteries in the middle may not be a big deal since lower voltage just means the fan is slower.
Even if you couldn’t get the Nivea one, you could buy a commercial solar USB charger.
The OP amuses me a little because when I was a kid I took a toy truck that ran on a single AA battery (Stompers, remember them?) and a solar panel from a calculator. Attached the wires to the copper bits in the battery case and away it went. I thought it was pretty cool.
Never thought of it as ‘hacking’ the truck or considered current & voltage requirements. Guess I just got lucky.