If your home needs a simple and inexpensive cooling solution, the best choice is a dual hose self evaporating portable air conditioner when no other option aside from a free standing unit is allowed.
That means you cannot install a window AC or mini-split system due to restrictions often imposed by landlords when you're renting. That can be quite a limitation especially when you have a very hot climate through summer, but it's not all bad news.
To get around many rented home restrictions, a portable AC is usually the best way to keep cool in summer. That is unless you're lucky enough to live in a very dry climate where a swamp cooler is a far cheaper-to-run alternative.
For the majority of people, living in a more humid climate means you won't get much cooling from a swamp cooler and AC is the only realistic solution. There are two variants of portable model that you can buy.
The more common type is the regular, single exhaust hose unit that unfortunately has a drain hose and/or water tray to catch condensed moisture that is produced by the cooling process inside the unit. There are dual exhaust hose models too, but they still need to be drained or have their water tray emptied periodically.
The other type is the self evaporating portable air conditioner. This model generally has a dual hose exhaust system for better economy and efficiency but the most important feature is the lack of condensed water to be drained or caught in a tray!
All air conditioning devices produce condensation internally as a result of taking warm, moist air from the room and chilling it. As the air chills, the moisture condenses on the cold pipes inside the unit.
Instead of allowing that condensed water to drip down into a drainage pipe or tray, self evaporating units re-use that water to increase the efficiency of the cooling process, then it is re-evaporated and expelled out of the unit via the exhaust hose, through the window to the outside. This process helps to reduce the energy usage of the device making it more economical to run.
It also does away with the need to drain the excess water away or empty a tray. If you're thinking that is a great idea and less hassle, you'd be right!
Self evaporating models do cost a little more to buy than their non-evaporating counterparts. But those dollars are soon recouped by enjoying slightly lower energy bills than you would otherwise have gotten.
For that reason alone, these machines make a pretty good investment. They're not as efficient as a window or mini-split AC, but if you can't install either of those types, it's the next best thing.
So when you're looking around the hardware store or browsing online for your new portable air conditioning unit, look out for a dual hose self evaporating AC from one of the major manufacturers and you won't be disappointed!