According to an article recently printed in The Industrial Physicist in order for everyone in the world to be adequately powered by 2050, an electric output 3-5 times greater than what is available now must be produced (roughly 20 terawatts), and it must be provided at 1/10 the current cost (about $.004.) The author David Criswell states that current means of power are not only too expensive, but also too polluting and unsafe. Nuclear power faces too much political and social opposition, and nobody much likes the idea of nuclear material getting in the wrong hands. Also, it is unlikely fusion power will be around by then. Solar power is too subject to the weather, and tide and geothermal systems will not be in high enough abundance. Wind power would take up too much land area. So what is it we can do to solve this problem? Criswell says solar power from space may be the answer.
Although he mentions the older idea of orbital satellites that receive solar power and transmit it to earth, he argues against such a proposal as inefficient compared to his plan. It would be both too expensive and would require way too much material being shipped into space. Instead he says, we must look to the moon for our source of power.
Strategically placed receiving stations around the world would receive power equaling 200 Watts per sqaure meter of receiving area. The power would be beamed from collection stations on the moon via 12-cm microwaves that would be able to pass through clouds and provide power during the night, things natural light is incapable of. The microwave would be harmless to both people and animals; anyone entering the beam would merely feel slightly warm, although people would not be permitted into the power grid on a regular basis and workers could be easily shielded. The only shortcoming is the microwave frequency would interfere with some wireless communication sources (especially cellular phones) which would have to be relegated to another frequency.
The power itself would be collected on the moon by a system of 10-20 pairs of bases, each of which consinsts of solar cells to collect sunlight, and buried wires to transmit it to the microwave generators. The technology to pull off such an operation already exists and it would be much more cost effective than building such a system in orbit as most of the materials could be built on the moon after an initial investment of machinery and personnel. The moon is also a more friendly enviorment for solar panels-no corrosive air, errosive wind, or rain and hail. Criswell vouches that moonquakes and micrometeors would have a negligable effect on the panels themselves. A limited working system could be produced in as little as ten years, and satellites could deflect microwaves to areas that are in too high or low a latitude, or that are not facing the moon at a given time.
David R. Criswell. "Solar Power via the Moon." The Industrial Physicist April/May 2002.