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by 44Aman 2677 days ago
How do they plan to beam energy back to Earth?
5 comments

Presumably lasers.

A small part of me wants to see this turn into China deploying a solar powered death laser under the guise of a green energy initiative.

Its in the article

>China's proposal, meanwhile, appears to suggest converting solar energy into electric energy in space, before beaming back to Earth using a microwave or laser and feeding into the grid via a ground receiving system.

Short version: they can fry a target in any country in about a day.
If the country is small enough they can fry that too. I can think of a likely candidate already.
Lasers? Microwaves? I'm just speculating but I don't see another way.
Do they need to? I wonder how feasible it would be to put large computational centers in space and have space solar farms powering these computational centers. So if we want to test complex or long-running programs/models/algos, we can just beam it to the computational centers orbiting earth and wait for the results when it's finished.
How do you cool them in space?
Radiators. Need pretty big ones if the computers want to run cool.

Probably would be better to manufacture most of the stuff on some asteroid or on Mercury and have the computation radiation shielded by a significant mass.

Do you need to? Without enough gas in space, how likely is it for something even as powerful as a data center to overheat?
You have gotten it exactly backwards. Vacuum is a great insulator, getting rid of waste heat is a huge problem in space.
What do you mean? The lack of 'gas' aka material to dump heat into is exactly the issue.
They'll recharge batteries that they'll then return to earth on a cheap BFR-like reusable launcher. /joke

Internet points to anyone who computes:

- how expensive that makes the marginal kWh returned to earth likes this.

- how low launch and return-to-earth costs must go for this to become competitive with current kWh costs.

First you build a space elevator to geosynchronous orbit, then you can use full batteries as counterweight for lifting empty batteries. That way you only have to overcome friction losses.
Even better! Now it's less of a joke idea. You still have a small shuttle transfer from geosync orbit to wherever the solar farm is (heliosync or a lagrange point to avoid earth shadow), but the delta-v for that is tiny.

However space elevators are still soft SF (still missing a material with enough tensile strength), whereas BFR cheap reusable launchers are hard SF, achievable with current known tech.