It's no secret that running the air conditioner eats up a lot of juice during the summer. It's also quite evident that room-based ACs use less power than central AC. The only surprise is by how much!
It seems that using room-based ACs rather than a central AC will cut your energy costs down by almost 50%! Why? Well, there's a lot less to cool down. It seems logical that you should only cool the place where you spend most of your time, instead of cooling down everything. For example, hallways, storage places, and other places don't need to be cooled.
This was initially reported about office buildings and how costs could be slashed if cubicles were cooled down with AC instead of the whole building. This makes a lot of sense. We see no issues using the same logic when it comes to homes. You don't need to cool down every single spot in your home, just the places where people tend to hang out most.
A good way to go about this in a home is to use a portable air conditioner, like the one we reviewed here. You can just move it around so that it cools down the place where you actually are, instead of your whole place. Naturally, this also applies to heating, however most heating systems are now room-based. Even so, you can cut down on heating costs by using space heaters. Check out this post for cheap ways to winterize your home.