My propane generator puts out a max of 7.5 kw. Running both A/C's it uses around .4 to .5 gallons per hour. Pretty efficient, but I'm like Forest...I don't care how much it uses as long as I am cool. The only time gallons per hour has become an issue was over the 4th of July when the park power went out for 13 hours. I hadn't filled up with propane since January 31st and was down under 10 gallons, and wasn't even sure if I had that much left, so I went outside and sat in a wading pool all afternoon....