At our rates here, that would be over $600 bill!
Computers add up, especially if you are running some servers. The heat of those also adds to your A/C bill. Refrig./freezer if they are more than 10 years old eat up a lot. Little things like power cubes for stuff add up, when you multiply by 24/7
You can buy a device like Kill-a-Watt to measure power consumed by anything you can plug into it. An electrician could install power monitors on the big A/C loads.