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Harvesting solar power in space and sending it back to Earth

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31–40 of 83 posts

Re: Harvesting solar power in space and sending it back to Earth

#31
It would be nice if the article had some absolute minimal details on how about 10 terrawatts of power[1] is going to be beamed down, and if that's a no brainer, over what area is it going to be beamed down.

[1] Based on energy consumption figures from http://en.wikipedia.org/wiki/World_energy_consumption

Re: Harvesting solar power in space and sending it back to Earth

#32
post #7

"Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so then you say, okay, solar…

> and that double conversion is going to get you back to where you started, basically

That feels overly simplistic. What are the actual losses?

Re: Harvesting solar power in space and sending it back to Earth

#34
Taking aside feasibility of this, having a single source of power delivering 33% of world's energy is a terrible idea. Especially if it would not be quick to fix or replace if it'd had been completely destroyed. Such a single point of failure would become a single point of doom if the world suddenly would be cut off of third of its energy for weeks or months.

Re: Harvesting solar power in space and sending it back to Earth

#35
post #34

Taking aside feasibility of this, having a single source of power delivering 33% of world's energy is a terrible idea. Especially if it would not be quick to fix or replace if it'd had been completely destroyed. Such a single point of failure would become a single point of doom if the world suddenly would be cut off of third of its energy for weeks or months.

Except it's not a single source. It would be dozens of satellites, hundreds ground stations etc. This is like claiming that "coal power" is a single point of failure.

Re: Harvesting solar power in space and sending it back to Earth

#36
post #7

"Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so then you say, okay, solar…

Who cares about the efficiency when solar panels weigh over 50 kg per kW? Even at SpaceX prices, the cost of launching a solar panel into space is hundreds of times the cost of the panel. If your alternatives are "buy 500 panels and put them on the ground" and "buy one panel and put it in space," why the hell is anyone even remotely considering the second option?

Re: Harvesting solar power in space and sending it back to Earth

#37
post #7

"Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so then you say, okay, solar…

I think beaming the energy down is the wrong approach, instead that solar energy needs to be converted to antimatter.

Re: Harvesting solar power in space and sending it back to Earth

#38
post #9
post #7

"Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so then you say, okay, solar…

What if instead of solar panels, you put up big mirrors, and instead of earth you have them orbit far closer to the sun? Btw, great quote.

yes, and shuttling antimatter batteries back to earth.

Re: Harvesting solar power in space and sending it back to Earth

#39
post #35
post #34

Taking aside feasibility of this, having a single source of power delivering 33% of world's energy is a terrible idea. Especially if it would not be quick to fix or replace if it'd had been completely destroyed. Such a single point of failure would become a single point of doom if the world suddenly would be cut off of third of its energy for weeks or months.

Except it's not a single source. It would be dozens of satellites, hundreds ground stations etc. This is like claiming that "coal power" is a single point of failure.

“According to his calculation, one such satellite is able to supply a third of total energy needed by humans.”

I'm just commenting on what they wrote and I see nothing about a farm of satellites in the article. Perhaps the original source is more clear about it. Or maybe this technology doesn't scale down well and that's the reason they're writing about one powerful satellite?

Re: Harvesting solar power in space and sending it back to Earth

#40
post #7

"Let me tell you one of my pet peeves: space solar power. Okay, the stupidest thing ever. If anyone should like space solar power, it should be me. I got a rocket company and a solar company. I should be really on it, ya know. But it's like, super obviously, not going to work because, ya know, if you have solar panels - first of all, it has to be better than having solar panels on Earth, so then you say, okay, solar…

Why would you put solar panels up there? Why couldn't you just focus the energy into a beam and point it towards earth like space based mirrors for one of these solar power stations[0] where sunlight is focused on a 'boiler' which generates steam for a conventional turbine. I've no idea if the physics works out but i'd be interested to hear from someone who does. [0] http://en.m.wikipedia.org/wiki/PS20_solar_power_tower
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