Possible Duplicate:
Can you create energy out of nowhere ?
I recall reading that Nikola Tesla suggested that electricity could be created from the air. This claim is stated in the following quote from a humourous comic on the Oatmeal:
You know when you need electricity for your home it simply rains down from the earth's ionosphere and charges everything wirelessly? ... Oh right, that was something Tesla invented but didn't share with the world ...
and also, similarly:
One of Tesla's final gifts to the world was a tower near New York City that would have provided free wireless energy to the entire planet. The man who financed the construction of the tower shut it down when he learned that there would be no way to regulate the energy and therefore it wouldn't make money.
Have these inventions since been proven as a viable and useful technology? Do we now understand how these inventions worked, and could either of them have provided energy enough for millions of people around the world to power heat, A/C, lights, computers, stoves, refrigerators, and other appliances?
EDIT I have edited this question so it is narrower than creating energy out of nowhere, specifically limited to those claims about inventions made by Tesla that I found referenced in the Oatmeal comic. (I leave it to a moderator to remove the Possible Duplicate note above and re-open, at their discretion)