I went to the car and looked up prices for the closest 4 stations, all 0.34 $/kWh. (Crestview, Defuniak, Navarre, Panama City)
Now how much will you use per mile? My Model 3 (highway use, 80,000 miles) 290 Wh/mi. My Model Y (mixed use, 6,000 miles) 280 Wh/mi. The car calculates this. So say 300...