You can make a homemade solar fan by using a low voltage DC motor, propeller or fan blade and a small solar panel and a mounting surface.
Attach the solar panel to a mounting surface, attach the DC motor and connect the motor to a small battery and the solar panel to the battery.
Then attach a fan blade to the motor shaft and ensure the solar panel faces the sun to generate power to run the fan.
You can also just buy a 12 volt DC fan and use a solar panel to power it with a battery.
You can also buy solar powered fans already made and ready to use for not all that much money.
Another way to make a solar fan at home is to take a battery holder (2 AA batteries) and wire it into a 1.5V to 12V step up circuit.
After you have it outputting 12V you can hook it into the fan.
Finally you can hook it into a PV cell into the circuit so that it will charge the batteries.
The fan that is best for solar system is a 12 volt fan that runs directly off of the DC voltage and so you don't have to convert the DC to AC.
When you convert the DC to AC to power an AC fan the battery power is drained faster than it would if you just used a 12 volt DC fan.
The DC to AC converter also uses power from the battery so you will require more battery power to power the AC fan off the DC to AC converter.
Although you can still power an AC fan off the DC solar system with a converter if you need too but the batteries will drain faster.
You can also buy solar rechargeable fans that have a built in battery and power it with a solar panel.
A good solar powered fan is the 14" solar rechargeable floor fan for outdoors with a 15600mAh battery and has a 20w solar panel that powers the fan.
You can buy the solar powered fan on Amazon.
You can also buy other indoor floor fans on eBay that can be kept charged and powered by solar panels that it comes with.