In a pilot study conducted by Verizon, the company found that Windows “sleep” features can actually cut energy costs by $65 per computer, annually.
Geez, you’d think Microsoft would have enough $$$ to do their own study.
Anyway, here’s the skinny on how much the communications giant is saving by having their PC monitors go zzzzzzzz… when no one is looking at them.

Hey Monitor, you're getting sleepy... very, very sleepy
Your mileage may vary, but we suggest you check the sleep function is working properly on your own PC or laptop.