My guess is that it’d take 20 to 40 hours for a full charge. Solar charges do tend to take a while to charge up batteries. If the solar panel is used in addition to a standard electricity supply, 24 hours would be enough.

I wonder how long it actually takes to charge the batteries. I’m doubting that you can use this thing continually… a full charge will last for 24 hours but after that it probably can’t keep up.