I thik that the main problem here, as in the flying turbines, is the means by which the power is to be transmitted to earth. They say radio frequencies, meaning microwaves, as you can keep a fairly focused beam. However, think about this: are they going to send millions of kwh of energy on a microwave beam to earth? On how many microwave beams? I can already hear the howl of protests all over the planet. Heck, some people consider microwave ovens dangerous!