By 1985, the Solar Power Satellite was essentially dead, killed off by the plumetting price of oil. But the technology developed for it was still valid, and Rockwell thought there might be a use for microwave power transmission systems. Their idea here was to use a space-based nuclear reactor – apparently something along the lines of the SP-100 – to generate electricity and then use SPS-derived microwave beaming tech to send that power to distant “customers” such as space stations and satellites. This would permit the customers to basically have nuclear power, but without the risks of having a nearby radiation source. The receiver would be much lighter than a PV array in terms of construction, and vastly more efficient, since all the energy coming in is of a single fixed frequency. A space station could presumably have a power receiver in the form of a mesh “net,” perhaps a single sphere a few meters in diameter at the end of a modest mast, capable of capturing dozens to hundreds of kilowatts of clean electrical power. This would lower the cost and mass of power systems compared to PV arrays… and it would greatly reduce the drag produced by those giant sails.
