we are set up on a plan that takes the average for the year on electricity and then breakes it up for each month that way you pay the same each billing period. but appearently we were at 275 a month and mow the average is 350, so the overage is tacked on to each months bill now totaling 400. i know that it is not just the tanks causing the increase, there is also an above ground pool we put in last year, and also the house is 250 yrs old so there are a lot of places to lose heating an a.c.