On the other hand, they can be built in an existing agricultural field and the field can still be farmed.

Here is the problem: They are cited very carefully to give maximum returns for the investment. Sometimes that means taking out a wetland, or impacting on some rare bird, or whatever. If they could be cited less optimally and still be “viable” this could be avoided.

Similarly, the design may not be ideal for birds passing by as you point out. But there probably are designs that would be more bird-friendly. But since they would not be designed to maximize return on investment, they would not be built. But if they could be, this would be avoided.

The solution? To recognize that the loss of profit is not acceptable in a pure free market model, but is acceptable in a socially and environmentally responsible manner. If you just regulate against adverse effects you squelch development. But if you PAY for it, you get both. Federally and by state there should be a fund to pay for part of the development costs as long as siting and turbine style conforms to certain guidelines.

This way there would be more wind turbines built on existing agricultural land of designs that have less impact.

Thank you for taking time to write about this subject.