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Will the stars align for space-based solar power?
- pingswept 17y agoThis does not look promising. Powersat suggests that they will be transmitting energy back to the earth at an areal density of less than 230 W/m^2. The sun, when it's shining, is around 1300 W/m^2. With night, clouds, atmosphere, and the like, the average available energy is in the range of 100-200 W/m^2-- similar, but free. Given that we already have the sun providing us with radiation, why spend the money to build a second one?
- skorgu 17y agoMy non-expert understanding is that the efficiencies come out better in the big picture despite adding a conversion step. You can get maximum sun time in space for the solar component and have a very cheap and very efficient rectenna on the ground that isn't much affected by atmospheric losses.
- graphene 17y agoThe difference is that the satellites' 230 W/m^2 is in a very narrow frequency band, and can thus be harvested and converted efficiently, where solar radiation is mainly at much higher frequencies, and, more importantly, spread out over a wide spectrum of frequencies. Our current best methods for converting these high-frecuency photons (solid state solar cells) only work well around a specific design frequency, and so they can convert only a limited part of the solar spectrum.
- onreact-com 17y agoWhile this is good news I still believe that current projects to get solar energy from sunny areas in deserts like the Sahara are more feasible.