What uses the most electricity in your home? Your fridge? Nope. Your A/C? Nope. It's the cable box on top of your TV! 

Experts say that one HD cable box uses about 10-percent more electricity than an energy-efficient refrigerator. That's because the computer drivers run full-tilt, 24 hours a day. In fact, two-thirds of the power is wasted when nobody’s watching! 
So what can you do? Well turning off the box doesn’t do anything but dim the numbers on the clock. So unplug your cable box when you’re not using it or plug it into a surge protector that you can flip on and off. It’s true, the boot-up will take a while; it might take up to half an hour. But you’ll see a definite difference in your electric bill.