11.5PHs will give you a daily 1 in 3 chance of finding a block. That's probably a good place to start, but will need to increase it about 5-10% every two weeks to keep up with difficulty increases.
well...
on eS9 is doing 13THs
to get 13,5PHs you need 1000 S9
and you will consume 1,3MWatts
I think it's a bit too much