Where did I say it's running 24x7?
At 24x7 the box used $12 electricity per month 2 years ago when I hooked it up to a Kill-a-Watt. For the 8-9 hours per week of recording and watching I do I'd have to be crazy to run it 24/7.
I save $8-$10 per month in electricity, more than the subscription costs me.