Technology takes a lot of power, and can add to your electricity bills pretty drastically if you aren’t keeping your computers under control.
If you are keeping your computers on at night, you should be turning them off. Not only will you keep your power bill down, you’ll actually extend the life of your machine by keeping everything switched off.
While you’re at it, you should also consider turning off your monitors if you aren’t using them for more than two hours at a time. Write up a computer policy and distribute it to employees. The electricity charge you save might not be worth much, but combined with other cost-saving measures and you’ll end up saving some real cash.