Don't know if this helps or not but...
I remember seeing a conclusion of an energy balance from this proposed alternative energy source
http://www.gedwardcook.com/wavegenerator.htmlThe claim was (and I cannot confirm or deny it) that if all the world's power was obtained using these, then the Earth's rotation would slow enough to lose 1 day every 2000 years. I dont know if this meets your definition of disturbing the balance or not...
You get a brownie point for recognizing the first law of thermodynamics though.
Go down to the ocean with an eyedropper. Take some water out of the ocean.
There. That's about how much windfarms and all other things would "affect" the planet.
The planet is REALLY FREAKING HUGE. Go out on a boat during the sort of storm where the waves are above you. You'll realize how big it is, and how very very small you are.
While more or less accurate, I would characterize this as taking a dropper of water off of the planet for every person on the earth multiple times a day. Then you ask yourself, "At what point does this make a detrimental impact?" Eventually it will. The question, however, is it far enough away that we really don't have to worry about it?