Using standard military ordnance has the advantage of a rapid deployment, minimising time between issuing the strike order and its execution.
Wind farm turbines are dispersed structures, so each must be attacked separately.
I would suggest that a flight of 40 aircraft such as the F-16 be used, each carrying 6 AGM-65 Maverick air to ground missiles, each missile costing US$17,000. A maverick missile is easily capable of destroying a wind turbine when targeted upon the upper housing, where its shaped-charge warhead could destroy any number of critical components that would lead to the turbine failing completely.
As an even lower cost solution, the 40 aircraft could open fire on the wind turbines with their GAU-4 20mm cannons. An F-16 carries 511 rounds for its 20mm cannon, and approximately 100 rounds would likely do sufficient damage for an operating wind turbine to tear itself apart. At 27 dollars per round, the cost of destroying one wind turbine with guns would be approximately 2700 dollars.
If both Mavericks and guns were used, 20 aircraft could take out the 200 wind turbines at an approximate ordnance cost of $9850 per target.
The possibility exists to use one GBU-39 glide bomb per tutbine at a minimum cost of 40,000 dollars per unit, or one GBU-32 JDAM per turbine at a cost of $18,000 each. From this, it can be seen that the AGM-65/20mm solution is the cheapest option in terms of ordnance expended and fewest aircraft. The 20mm solution is cheapest if there is no limit to the numbers of aircraft that may be deployed.
Obviously, the cost of operation of the launching platforms are not included in these figures.