I’m only half kidding. I’m a bit of a prepper and I have lots of powerbanks and devices that charge from USB but besides idling my truck I really had no other way to charge any of them in case of a long-term power outage which seemed a bit of an oversight on my part.
Not like this solves the issue. 30 watts (under ideal conditions) isn’t much but it’s a start.


That’s exactly the use case I bought it for. In the picture I’m charging a powerbank. I’m intending to play around with a small-scale solar setup on my shed at some point but for now this is the one cheap investment that enables me to keep critical small electronics running indefinitely.
Check out some auctions, estate sales and such for some deep cycle batteries, solar charge controllers and panels. I have fixed my set up a few times over the years on the super cheap that way. The whole system is not bad other then the batteries for cost.