you might have to take some items off of your wishlist.
Well - the problem is when they (previous owners) put the addition on my house, of which the shop is a part of, they used a single 15 amp circuit for the shop, a few plugs in the house, and various ceiling fans in the bedrooms (weird, I know - but it apparently passed inspection). In my shop I have my "server closet", which I current run two small servers off a large UPS plugged into one of the outlets in the shop (which is inside the closet).
I haven't had any issues with the power, but I think with the addition of an A/C unit, plus later I plan on hooking up another small PC for my workbench, plus my soldering iron, oscilloscope, and maybe later my mini-mill - I think I am getting close to the "trip point" of the breaker (I haven't actually measured, so I don't know for certain).
Which is why I wanted more circuits to spread the load; I realize this may not be possible if I am at my limit on the breaker box and/or the service level from the power company. When I do have this done, I plan on having a real contractor do it - this isn't going to be a DIY job; I want it done right so the house doesn't burn down!
they make mini-splits that take 120VAC and draw less than 15 Amps, it will only provide about a ton of cooling or so but it is probably more than your portable puts out
My shop is small - maybe 8' by 15' max; in theory, from what I have read, my current A/C unit should be able to cool it, but because of the hose and the fact that I don't have an easy way to lead it outside without a big gap in the door, etc - it just isn't working for me. I am planning on trying some other possibilities with it - maybe I can get it to work.
Since the split a/c unit is something for the future, I am trying to come up with a solution for "now" (short of just waiting out the summer); if I can't get the portable working the way it should, and I have no luck with the swampie (because of monsoon season), I am thinking about a way I can mount up a window a/c unit thru some kind of temporary "baffle" in the place of the door, made out of either 1/2-3/4 inch plywood, or maybe some kind of styrofoam board (and mount the a/c unit on a stand in front of the cutout hole). I am not sure how well this would work, but it might be worth the effort.
This summer has seemed to be hotter than last summer (maybe due to the monsoon?), certainly; not sure if that is truth or just faulty perception. If I want to do something in my shop, though, I need to figure something out, or just forget it until the cool season comes back.