Tvheadend

Hi all,
Not sure if this at all possible but just thought I would ask you helpful bunch :).
Here is where I have got and what I'm trying to do so far.
I have now got the server into the front room after hours of setting it up I decided to go with kodi buntu install with tvheadend for my main source of tv.
This will be in my tv unit plugged In to the tv for me and the family to use downstairs.
I have 3 fire sticks one in mine and the Mrs bedroom and 1 each for the kids so we can connect to live channels from the main unit in the front room.

What I would like to do is try and make the computer go to sleep when no body is watching anything or nothing is recording. Then when anyone of us call for a live channel it switches back on by it's self.
Is this at all possible
Thanks