50 acres per turbine seems bizarrely huge. Where does he get that?
Seems to be an average:
Snowflake, Ariz. 99 MW/7,000 acres 71
Altamont Wind Resource Area, Calif. 580 MW/50,000 acres 86
Fountain Wind, Shasta Co., Calif. 347 MW/37,436 acres 108
Montezuma Hills, Calif. 180 MW/6,800 acres 38
Pine Tree Wind Farm, Tehachapi Hills, Calif. 135 MW/8,000 acres 59
Tule Wind Project, East County, Calif. 131.5 MW/12,000 acres 91
Cheyenne Ridge Wind Project, Colo. 500 MW/100,000 acres 200
Colorado Green, Lamar 162 MW/11,840 acres 73
Prairie Wind, Colo. 69 MW/7,000 acres 101
Twin Buttes, Colo. 75 MW/9,000 acres 120
Winergy offshore, Del. 1,101 MW/67 mi2 40
Cassia County, Idaho 200 MW/4,500 acres 23
Boone County, Ill. 27 MW/800 acres 30
Baileyville Wind Farm, Ogle County, Ill. 80 MW/5,000 acres 62
Big Sky, Ill. 75 MW/10,000 acres 133
Bishop Hill, Ill. 400 MW/25-30,000 acres 62-75
Crescent Ridge, Ill. 54.5 MW/2,200 acres 40
LaSalle Country, Ill. 384.5 MW/25,000 acres 65
Mendota Hills, Ill. 50.4 MW/3,500 acres 69
Rail Splitter, Ill. 100.5 MW/11,000 acres 109
Twin Groves Wind Farm, McLean County, Ill. 396 MW/21,000 acres 53
Walnut Ridge, Bureau County, Ill. 225 MW/14,000 acres 62
Jordan Creek Wind Farm, Warren County, Ind. 300 MW/27,000 acres 90
Cerro Gordo, Iowa 42 MW/2,110 acres 50
Franklin County, Iowa 200-300 MW/40,000 acres 133-200
Pomeroy Wind Farm, Pocahontas County, Iowa 198 MW/8,200 acres 41
Elk River, Kan. 150 MW/8,000 acres 53
Ford County, Kan. 100.5 MW/5,000 acres 50
Smoky Hills, Kan. 100.8 MW/20,000 acres 198
Spearville, Kan. 100 MW/10 mi2 64
From here: http://www.aweo.org/windarea.html