Mitigating Climate Change: Solar Power Satellites.

Short radio interview on the practicality of Solar Power Satellites. I first saw these suggested back in the 1970s. Supposedly the technology is "off the shelf," and, also supposedly, the oft-cited issue of danger of birds or aircraft intercepting the microwave energy and being harmed is also not a problem (that would have to be unequivocally demonstrated). Cost per equivalent power generation (including rectifier array on the ground, which uses quite a bit of land): approximately the same as the cost of a nuclear power plant (which is much more expensive than coal or gas generating plant in construction costs). But the upside of course, is no greenhouse gas emission at all, and no use of energy resources that could be used elsewhere (the only opportunity cost is the use of land resources to receive beams, and the finite amount of space in geosynchronous orbits; you can't build an infinite number of these things).
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