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0 pointsjim-greer9y ago0 comments

How could you store enough power in orbit to fire it?

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Well, you could use your handy 200 GW solar array. With perfect conversion, and ~1300 W/m^2, you'd need to get your 12km x 12km panel array pointed consistently at the Sun.

imaginenore9y ago

You actually don't need anything crazy like that, as you don't need continuous 200GW forever, only for 2 minutes. You just need enough energy storage so you "only" need to store 6.6 gigawatthours.

Lithium ion battery energy density is 265 watthours per kg. So you will need 24.9 million kg of batteries. Or 24.9 thousand tons. It's a lot, Tesla factory makes more per year.

j / k navigate · click thread line to collapse

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mturmon9y ago

Well, you could use your handy 200 GW solar array. With perfect conversion, and ~1300 W/m^2, you'd need to get your 12km x 12km panel array pointed consistently at the Sun.

imaginenore9y ago

You actually don't need anything crazy like that, as you don't need continuous 200GW forever, only for 2 minutes. You just need enough energy storage so you "only" need to store 6.6 gigawatthours.

Lithium ion battery energy density is 265 watthours per kg. So you will need 24.9 million kg of batteries. Or 24.9 thousand tons. It's a lot, Tesla factory makes more per year.

j / k navigate · click thread line to collapse