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Comment by a_crc | Hacker News Reader

It's a lot of solar panel. A quick search gives us a figure of 220 watts of power per square meter of space based solar panel. This would mean a 200MW solar collector would need to be almost a million square meters in size. For reference that would be a square the length of 155 NYC city blocks on each side.

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> A quick search gives us a figure of 220 watts of power per square meter of space based solar panel. This would mean a 200MW solar collector would need to be almost a million square meters in size. For reference that would be a square the length of 155 NYC city blocks on each side.

200MW/(220w/m2) gives us an area of 1,000,000m^2, a square 1000m on each side.

(side note: a NYC block isn't a very good length reference - they vary[1] from 250ft to 750ft depending which direction you're measuring. So the square would be 4 to 12 blocks on each side)

[1] https://streeteasy.com/blog/how-many-nyc-blocks-are-in-one-m...

Hmm... or maybe some smaller panels plus a really enormous and very very thin reflective collector for concentrating solar. Keep in mind that things can be very thin in space.

It would still weigh a lot though, and heat would be a major issue. You wouldn't want to melt the solar panels.

This would require someone much more knowledgable to determine if it's feasible.

Edit: I wonder if you'd get some amount of solar sail effect in addition to the plasma rocket? Of course this would help you one way and hurt you the other way.

A million square metres is one square kilometre. It could be built but it would be heavy. A circular sail with a radius of just over 600 metres would do it.

wouldn't a million square metered be a megametre and not kilometre?

no. 1000m * 1000m = 1000000m^2 or 1 km^2

That's if it's illuminated by the sun. Blast it with a 500MW space-based laser and you'll up the tempo.

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