Government scientists have projected that the cost of electric power generation from such a system could be as low as 8 to 10 cents per kilowatt-hourbut of course no specific citation. The recent DoD report saw initial prices at around $1 per kW-hr, dropping with experience.
One interesting proposal in the brief article is to run a demonstration on the space station:
a practical first step would be to conduct a test using the International Space Station as a construction shack to house the astronauts and equipment. The stations existing solar panels could be used for the demonstration project, and its robotic manipulator arms could assemble the large transmitting antenna. While the stations location in orbit would permit only intermittent transmission of power back to Earth, a successful test would serve as what scientists call proof of concept.Sounds like a good idea! Since it's more than 10 times closer to the surface than geosynchronous orbit, building an antenna at 1/10 scale (100 meters diameter, say) would be an interesting test that could actually deliver (and receive) power.