Solar Panels On The Moon?

I caught the end of an episode of "Naked Science" last night about the moon. What I found interesting is that they were talking about using machines to create solar panels right there on its surface. I forget how many miles it would take but they said they could power the entire worlds energy source we use everyday by doing this. Another interesting thing was that they could use radio or some sort of radar to send the energy to the earths surface and receive 80% of the solar power energy. They are hoping to have this in effect by 2020, that would be a great way to use the moon since it appears unoccupied. I tried to find the video on you tube so I could watch it for more facts but was unable to find it, if you come across this video "Inhabiting the moon" (I Think its called), I would say its a must watch.