its not for financial reasons... its my little pipe dream to help me keep my chin up if i end up on the scrap heap
i like the idea of the old travelling knife sharpener :)
this charge controller will take 38v open circuit, i'm sure that's pretty typical for a cheap 250w panel

my cnc draws 130W 150W typically... it would draw a shitload much more if i leathered it but i took measurements on a typical run... my desktop will draw more than that when its rendering HD files
im pretty sure i could run for six hours before i got to 50% then sit in the dark until the sun comes up lol