One cannot power the entire earth electrically from a single source. The iron core will dissipate the current flow. There was a lot about earth geology that Tesla did not know. And his scheme to transmit electric power wirelessly is extremely inefficient. Electrical energy, however, can be beamed by transforming into microwave emission transmitted as a tight beam. Broadcasting electric power is simply too inefficient to work.
Even so, Tesla was a genius, the father of A.C. power and the true inventor of practical radio transmission of data. The courts ruled that Tesla, rather than Marconi had precedence in 1942.
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