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0 pointsDennisP7y ago0 comments

The costs I quoted include everything, including manufacturing and maintenance. The book breaks down all these costs. In the 4 cents/kWh scenario, launch isn't the dominant cost anymore, and dropping that further wouldn't make much difference.

You don't put a battery on a solar power satellite. To whatever extent you need battery, you put it on the ground, but you don't need much because a satellite in geosynchronous is in full sunlight almost all the time.

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AstralStorm7y ago

You want to put it in synchronous? How do you keep it lit up all the time?

You do understand you need many more panel fields as opposed to receiving stations that way and half of them is wasted anyway?

I thought the idea is to put them in solar Lagrange or solar synchronous orbit and bend or reflect the maser to stations. 24 hour lit, though a bit trashy if Lsun is used.

The math is suspicious anyway. Wouldn't it mean that the panels would cost 25% of this on ground?

DennisPOP7y ago

Due to axial tilt, for most of the year geosynchronous satellites are in full sunlight 24/7. Twice a year, around each equinox, there's a period of 44 days during which the satellite goes into shadow briefly each day, for a time ranging from 2 minutes, to 72 minutes at the maximum.

https://corpblog.viasat.com/how-satellites-are-affected-by-t...

This compares pretty favorably to capacity factors of other power sources.

Illumination per square meter averages quite a bit higher than ground solar, and except for the brief times in shadow is 30% higher than ground solar at noon.

The book evaluated other locations including Lagrange points. Everything had pros and cons; the main disadvantage of Lagrange points was the greater distance, requiring bigger antennas. I think more delta-v in deployment was a factor too, though I forget by how much.

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