These are the sort of things people buy their pensioner parents
in the middle of summer, as a cheap solution to cooling a room
Unfortunately, they suffer from some heat leakage. I have seen
a claim that you can reduce this by insulating the flexible duct
that goes out the window, but that is not the complete answer.
I have looked at some in shops, and if you feel around it,
you can always find a warm corner or two on it.
So I wonder about the ratio of (cooler power)/(electric power in)
how does this typically compare to a (fixed) split-system?
I know there exist some portable split systems - delonghi and one of
the Jap companies make them, but they seem to be pretty rare.