I dont remeber what my kwh/hour is but tanks are not what is going to run up your bill. My tank is the last of my concern on my electric bill. I do things such as keep my ac at one setting and dont touch it (I keep mine at 77-78sh). You can also turn your AC off for one hour every day when you are not home.(you can set it on a timer). I use energy effienct bulbs (still swapping out now, but my mom did at her house and she said it made a big difference). We dont use lights or turn things on if we are not going to use it, we turn it on when we use it and off when we are done. During the day we hardly have anything other then the tank on unless we are on the computer or cooking. You can tint you windows and that will help also. There is all kinds of things you can do. Try some of those if you think you bill is to high. Most electric places in FL will come out and do a free home energy saving inspection (idk about other states, but you can ask). I had 5 tanks running at one point in time and it really didnt make the difference on the bill.