Someone once told me that window cooling system units are better and more energy saving if you have an outdated home, however running a central cooling system in an outdated loft can end up costing you more to use the thing, and also, it is possible that the loft may not even have ductwork, so that alone would cost a fortune! I never had entirely thought about this, because I have been using central cooling system for decades now.
Because I live in the south, having window cooling systems are not honestly an option, but everyone has central heating and cooling system.
If you were to try to have a window cooling system in the south, you have a lot of potential problems to deal with, then not to mention, there are no windows in the way these homes are built that would accept a window cooling system! However, if you have an older loft and live in the south, you can get yourself a portable cooling system unit, or maybe even a swamp cooler mixed with a portable cooling system unit. However, back to the point on hand, I did find out that having a window cooling system unit does save tons on energy use in an older home, instead of a central cooling system, and so, if you have an outdated home, go with the window cooling system unit if you do not live in the south area of the USA of america! That is what I did for my older loft that I have as a Summer getaway in the north.