I've been building a Peltier with 48v solar in mind. Part of the design constraints were to create it using only commodity CPU cooling tech I could buy online, and plenty of trips to the hardware store.

Initial test run in the window to track cooling ability (which I expect to be fractional of a full compressor AC). This run using 110v mains power for consistency and testing. I've already run 48v, I just didn't want to be swapping batteries all day (and I need to improve my battery discharge safety features).

Runs around 200W (measured using Kill-A-Watt), COP is much lower than compressors, but I think it might actually be enough to take the edge off a warm room. The goal here is to have solar panels outside the window like shutters, and the unit running without any additional inputs... storing any excess power in batteries for night time operation. Low visual footprint as well, so it doesn't block the view.