The Tesla stuff is fool-bait, of course, but it is clearly possible to
transmit energy with electromagnetic beams. A flashlight and a
photocell is an inefficient example. An efficient example is a high
efficiency microwave transmitter and a rectifying antenna (this kind
of system has been proposed for transmitting power from orbiting
solar arrays to the ground, with a transmission efficiency in excess
of 80 to 90%.)
Paul