A plan to build half-mile tall solar towers in the Arizona tower took a step closer to reality with the announcement that "Southern California Public Power Authority (SCPPA) has taken a call option to purchase the first of two EnviroMission 200MW (megawatt) Solar Tower power stations planned for development in La Paz County, Arizona."
Phoenix-based EnviroMission announced last fall that it had two land applications with the Arizona State Land Dept., each total 5,500 acres (2225.85 hectares) "suitable in size for development of a 200Mw Solar Tower power station respectively."
The solar tower funnels air heated in a mile-diameter green house up the 2,500 tall tower, turning turbines along the way that generate electricity. [right, that's the Empire State Bldg at left in the figure. Credit, EnviroMission]