ok.. this might get long.. i'm about as cheap as a person can be and still be in this hobby.
i have 9 tanks running. heaters in all of them, most are set at 80 -82 degrees, except the growout tank which is set at 86 (but it's only a 60 gallon tank and the heater is kinda small).
i also have 3 15 cu. ft chest freezers and 2 "energy star" refrigerators. plus the washer, dryer, tv, dvd, cable box.. etc.. ALL of the lamps in the house were switched over to CFL about 8 years ago. and all of the appliances in the kitchen, and the tvs and chargers and lamps are on power strips that are turned off when not in use. or unplugged.
in the summer (because i'm too cheap to run A/C) my electricity bill runs between $100 -$150. in the winter, it goes up to the low $300s because of the aquarium heaters.
i am also going to take a clue from someone i respect immensly and put foam insulation around the sides of all of my tanks and plexiglass or glass covers on all of them instead of the egg crate that just lets all the warm out of the tanks.
this summer, i'm setting up the 240, and i'm consolidating tanks, and eliminating others. i'm hoping to bring my electricity bill down to under $100 for the summer and $200 for the winter.