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I'm pretty sure someone will figure out how to make a working solar sail that captures energy and beams it to earth via microwaves.

Please enough of them far away from Earth and you get pretty much unlimited energy all year round.




You get the same if you place solar panels in places around the equator, without all the messiness of orbital repairs and GW death rays. I can't see this being cheaper than just some panels on the ground.


The funny thing about solar panels is that they are the most efficient at very low temperatures. They'd be more efficient at the poles or high up in the mountains where they can be kept cool.

A solar panel in space would be highly efficient.


The death ray might be the feature that sells the whole thing.


I like the way you think.


Why would you want to do orbital repairs? For the amount of effort required, you'd just send up a replacement.


And we're saying that deploying new solar sails (with integrated power transmitters) to orbit is cheaper than replacing a solar panel on earth?


Not at the moment, but at some point it might be. Real estate on earth has lots of competing uses, so it has a lot of opportunity costs.


Eventually, the limiting factor will be how to get rid of the waste heat.

Even if you can turn 100% of the energy you received from space into electricity, in the end it'll all turn to heat.


Ok, so we get a really big heat pump that sends all the heat to space.


If only thermodynamics was this easy. Heat pumps ain't magic, alas, they are still subject to physical limitations, including the laws of thermodynamics.

Also keep in mind that cooling the hot part of your space heat pump is very limited: there's no convection nor conduction in space. You can only lose heat energy via radiation or ablation (= shooting away hot pieces).


Waste heat from microwave energy? Am I missing something?


I'm talking about waste heat from when you use the electricity.

Almost no matter what machine you are powering, be it a a toaster or a computer or an electric car or a washing machine, eventually turns all of the electric energy into heat.

(You can contrive some counter-examples. Eg if you point a sufficiently strong laser pointer at the sky, some of the energy will escape earth before turning into heat here.)


Inventing the Dyson Sphere one step at a time




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