I've done as much research as i can an every site i hit seems to have a different story on my question: "Will a dehumidifier save energy while running your AC through the summer"?
The ones that say "yes" pretty much reason that you usually can raise your thermostat a few degrees because of the lower humidity it will "feel" more comfortable. While they reason that yes AC do dehumidify also but it will put less of a load on your AC system.
The ones that say "no" say AC units doesn't run optimally when a dehumidifier is running (they don't go into details). Also, by design, dehumidifiers heat the air. How much of a difference that makes, i don't know.
That being said dehumidifiers do pull quite a bit of energy (i'm sure not NEARLY the amount of an AC unit though).
I live in zone 5 (central IL). Hot/humid summers and cold/dry winters. I don't need a dehumidifier for the winter (we actually need a humidifier then).
Also, as a lot of you probably already know, current dehumidifiers are some of the most unreliable appliances you can buy. Its one of the few things i know make sure i get an extended warranty for. I'm on my 3rd unit and, one of the reasons i'm here, is to find out if i need to budget for another one. Sure i'm sure there will be days when i could not run the AC and just run the dehumidifier but i don't think there will be enough of those days to warrant a dehumidifier if i really don't need one.
Best Answer
A dehumidifier is about the same as a window AC unit with both parts in the house, for most purposes. They draw just as much power as an A/C unit of similar size (or more if they happen to be old and inefficient.)
Given that the required energy labeling on A/C units tends to promote a degree of of paying attention to that, and it's much less clear on dehumidifiers, I suspect that in many cases the A/C of similar size will actually use less power - and it doesn't make your house hot.
Sure, comparing a room dehumidifier to a whole house A/C, the whole house uses more energy - but it also removes more water from the air, and cools the house. It would only be ANY savings if the whole house was LESS efficient (power in to water out) than the dehumidifier. If you are running the A/C as well, you are also ADDING the heat from the dehumidifier to the A/C load.
In short, run the A/C, don't bother with a dehumidifier unless you have a job that a dehumidifier (alone) is suited for; Which it sounds like you probably don't.
If you want to get "something like that" without the downsides, when your water heater wears out, consider a heat pump water heater - free hot water with a little A/C, or free A/C with your hot water. Still rather expensive, but sometimes with large rebates available too.