[robomartin]

There's no other way to put it: In some parts of the world you are simply screwed. I am lucky in that I have 50 to 60 degree air available at night during most of the summer. During the day it's 110+, so you learn to manage heat-flow very quickly if you want to save money. If I could get away with paining my roof white I would.

If I lived in an area where it's still hot at night and owned my own home I'd look into ways to store thermal energy at night when A/C units are more efficient. Here's a stupid example not fully thought out: I'd install a swimming pool as large as I could handle and chill that water at night.

A decent size swimming pool can easily have 25,000 gallons of water. Rough calculation: That's about 200,000 lbs of water. 1 BTU raises 1 gallon of water by 1 degree F. So, if you cool 200,000 lbs of water by just one degree you've stored 200,000 BTU's. A typical mid to large home A/C unit is 3 to 5 tons, which means 36,000 to 60,000 BTU's. As you can see, if you can efficiently cool down a large mass of water at night during high-efficiency and low electricity bills period you might just be able to sink heat from the house back into the pool during the day with a suitable heat exchanger. Again, seat of the pants stuff. I haven't thought it through in any detail because until I build my own house (on my bucket list) I have need to do so. So, call it a crazy idea at this point. Probably a bad one at that.