When plugged to the solar panel, how the fan works depends on the sunlight.
When the sunlight is strong, the fan works fast. When the sunshine is not strong enough, the fan may work low or even does not work.
The fan runs when plugged to the solar panel. And it can be used alone by plugged into computer USB port.
There is no rechargeable battery in the fan. If you need the fan works at night, you can use a power bank.
If our products have any problems, we can provide replacement / Return Service, welcome to contact us anytime!