You did not tell us which state where the property is located. This can make a big difference as states have differing rules regarding valuation for eminent domain.
If you don’t come to an agreement and if the company has the power of eminent domain (generally must be a common carrier or utility wind farms usually don’t have that power) then the company will likely file a condemnation proceeding.
In Oklahoma the court appoints commissioners who value the the value of the property taken and also the diminution of value to the property that was not taken. Either party can file “exceptions” (object) to the value and the matter is tried to a jury. Often the condemning party is required to pay the landowner’s attorney’s fees.
Court case where eminent domain improperly attempted. Case – Newspaper Article
The acreage you have in play, the assistance of an experienced eminent domain attorney in your state should be consulted. Be more concerned about the attorney’s qualifications instead of vicinity. The attorney’s experience is more important than his or her proximity to the courthouse in these cases.