Large assemblies of photovoltaic panels concentrate reflected solar light with clusters of mirrors, producing electrical energy that a powerful scanning electron transmitter sends to earth in the form of directional radio waves. At an altitude of almost 36,000 kilometers, there is so much space available that one of NASA’s projects calls for assemblies the size of Manhattan!

On land, a grid-like, large-mesh, circular receiving antenna connected to the power grid reconverts the radio waves into electricity. The antenna could measure up to 10 square kilometers and would therefore not be located in residential areas, although the land could be used for agriculture. The term “rectenna” (a contraction of “rectifying” and “antenna”) is used to describe this type of antenna, which will receive electromagnetic pulses and supply direct current to the high voltage power system using a rectifier. The system yields 5 kilowatts of power per square meter, i.e. about six to eight times more than the best performance from land-based photovoltaic installations located at medium latitude.