i know. i'm supposed to be working.

but this needs to get figured out...

the math with one of these charging ports just doesn't work, so i cancelled the order. the panels are just too small. if you're pulling in a watt, max, and you're pulling out 2-3, it's just not enough.

https://www.solarpanel.wiki/solar-power-bank/

so, what do i need? i should have done this from the start, i wasn't thinking clearly...

if i'm pulling 3 W constant all of the time, i need 24X3 = 72 W. i don't know how much wattage i can get from the leds, but i know it won't be much.

let's assume the worst case - that i can't get anything from the lights at all. then, i'll need the battery to run 20 hours a day in the worst days, and get all the sun from those 4 hours. 72/4 = 18. i need a 20 W panel...and a 20,000 mAh battery minimum.

on the other hand, if i can get the fan to run solely on the lights, then a 5 W charger should do it - and i won't need a battery at all. the signal from the leds should be constant, and it should just spin the thing.

i want to keep the cost down. and, i suspect i could turn a 5W charger into a component in a battery charger if it doesn't work. that will be one of the next things off the grid, and i can take my time with it.

so, i'm going to order a 5W solar cell that works in low light, without a battery. it should be a few dollars. it might not actually work, but if it doesn't i can use it for something else.