I have been looking into Solar Based Solar Power (SBSP) satellites to utilize the radiated energy of the Sun and utilize for use back here at Earth. The idea is that these satellites contain solar cells that would convert the EM radiation to electrical energy on the satellite and use this energy to produce Microwave radiation. These microwaves are then directed to Earth which is received by an Rectenna which converts the energy from the microwave radiation to electrical energy. This process is a form of Wireless energy transfer (WET).
What I want to know is the physics behind the energy transfer by the microwave radiation and roughly how much energy would be transferred?