MERGED QUESTION Question from napoleon44418 : "control tv away from home"
I need to be able to shut off my son's tv from 30 miles away.
Not exactly what u asked but some TV have sleep/power saving mode. After a time-out of not having hit any remote's buttons, it goes to sleep.
The only way I can think of doing this is to use something like a Raspberry Pi connected to the net controlling a mains relay to switch off the power. Not an easy thing to do unless you know some programming and electronics. Other than that there are now connected devices (like heating and lights) from Amazon and hive that may serve your purpose.