I just put in A/C last year and honestly my bills are cheaper than when I had a swamp Cooler and much more comfortable.We had fans going all the time probalby 24/7 with the swamp cooler and were miserable.I am also on a budget plan so that I have the same amount for a monthly bill year round,but still I have a 1700 sq foot house big windows and dogs going in and out several times a day,and I would say it is around 74 degrees in here and I only pay $100.00 a month