Should we launch a spacecraft to collect energy?

1 points by jlebrech ↗ HN
Should we launch a spacecraft along the same orbit in reverse and collect it in 6 months?

it could have a supercapacitor to collect the sun's energy and then we could use that to power the earth (or a country's) energy needs?

how big would it have to be?

2 comments

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I am not sure that smashing a supercapacitor (whatever that is) into the earth at twice orbital velocity will really do that much to help anything...

You could put a solar collector into earth's orbit so it would always be in the sunshine and <transfer the energy in some way>. However no one has a way of making this seem economic.

https://en.wikipedia.org/wiki/Space-based_solar_power

You need a LOT of fuel to make a spacecraft go in the reverse orbit. A LOT!!! To make hard turns the satellites use the gravity of another planet.

Also, the mass of biggest satellite we can launch now is only about a hundred tonnes (less than a boing 747), if it goes to a low orbit and it is much smaller if it has to go higher. With a back of the envelope calculation, you can store about 6 million batteries there. For comparison, the population of New York is 8 millions, so you can give them less than a battery to each one of them.

And increasing the mass of the satellite or the fuel amount, makes the fuel in the launching rocket much much much bigger. https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

Perhaps you can try to gain some intuitive idea about satellites playing the Kerbal Space Program game: https://kerbalspaceprogram.com/ The simulation is not totally accurate, but it's good enough and there are some mods to increase realism later.

(It's also not easy to store the energy for 6 months. Try storing a charged rechargeable battery for 6 month and using it.)

Note: This look like a nice question for https://what-if.xkcd.com/ You can try submitting it there.