I researched power inverters, figuring that I can charge my Macbook while camping. It turns out, as far as I can tell from the user reviews, that the affordable inverters (even some less affordable) don’t satisfy a PC’s AC quality requirements. There are happy customers, but the reports of failure for PC use are about 20%. Someone even added a UPS to clean up the power including the frequency — so that’s DC to AC to Battery to clean AC.

My purpose is some evening entertainment for teens at a camp, miles off the grid. They have a generator there, but I hesitate to trust it with my PC.

Some newer PCs charge on 5v, but I can’t afford newer.

My wife has a tablet (Sansung SM-T530NU Nook) that can be charged in my truck. But it rejects every attempt to load from the Macbook via USB cable or BlueTooth — the devices see each other, but can’t quite get a connection.
Only remaining possibility seems to be a micro SD chip.

Maybe the elements are conspiring to focus me on my 12-string guitar, and “the elements” have also watered the forest so we’ll probably get to light a fire. But the kids do get itchy being dragged away from their current tracks.