They have only applied, so get your formal objection in straight away. Personally I don't mind seeing the odd one or two for a property although I hate too many wind farms on the horizon. It is extremely upsetting if they are in your main view however.
Could you have a meeting with the owner and the planner involved on site and stipulate that although you understand their need for them, could it be agreed that they be located somewhere specific so it doesn't detract from your own property.
I wouldn't fall out with the owner if possible, best to let them see you extremely upset rather than angry, that way they may feel sorry for you rather than thinking they should be defensive.
Good luck

and try not to lose too much sleep over it or give yourself high blood pressure. I'm sure such things must affect people's health.

All the best FF.