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Building solar farms above the clouds

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Re: Building solar farms above the clouds

#3
post #2

Isn't it easier to modify the weather in an area populated with PV?

Modify it how? We have some fairly blunt instruments like seeding clouds to modify weather, but those wouldn't be of much use here. Of course, it seems a lot more straightforward to build solar farms in Arizona or Algeria, though transmission is still a problem. Possibly they could be used to generate hydrogen for synthesizing fuels...

Re: Building solar farms above the clouds

#4
post #2

Isn't it easier to modify the weather in an area populated with PV?

Modify it how? We have some fairly blunt instruments like seeding clouds to modify weather, but those wouldn't be of much use here. Of course, it seems a lot more straightforward to build solar farms in Arizona or Algeria, though transmission is still a problem. Possibly they could be used to generate hydrogen for synthesizing fuels...

True, seem to be harder to go the opposite way.

Something noteworthy: China plans to halt rain for Olympics - http://www.latimes.com/world/la-fg-rain31jan31-story.html

Re: Building solar farms above the clouds

#5
Solar in space is only about 2x more effective per unit area of solar panel than solar on the ground, after you deduct transmission losses. The costs, of course, are much higher. The enthusiasm for hydrogen as energy storage is misplaced. Electricity to hydrogen to electricity is maybe 40% efficient. Lithium batteries are 80% - 90% round trip.

In any place that needs air conditioning, solar power is very effective. Peak load and peak solar panel output line up nicely, and little storage is needed. Keep it simple.

Re: Building solar farms above the clouds

#7
post #5

Solar in space is only about 2x more effective per unit area of solar panel than solar on the ground, after you deduct transmission losses. The costs, of course, are much higher. The enthusiasm for hydrogen as energy storage is misplaced. Electricity to hydrogen to electricity is maybe 40% efficient. Lithium batteries are 80% - 90% round trip. In any place that needs air conditioning, solar power is very effective. P…

Lithium batteries are not portable, hydrogen can be. With sufficient solar power generation that forty odd percent efficiency would become a non issue.

Re: Building solar farms above the clouds

#8
post #5

Solar in space is only about 2x more effective per unit area of solar panel than solar on the ground, after you deduct transmission losses. The costs, of course, are much higher. The enthusiasm for hydrogen as energy storage is misplaced. Electricity to hydrogen to electricity is maybe 40% efficient. Lithium batteries are 80% - 90% round trip. In any place that needs air conditioning, solar power is very effective. P…

Some countries don't get much sunshine though, e.g. the UK only gets sun around 30% of the daytime according to https://en.wikipedia.org/wiki/Climate_of_the_United_Kingdom .

Re: Building solar farms above the clouds

#9
post #7
post #5

Solar in space is only about 2x more effective per unit area of solar panel than solar on the ground, after you deduct transmission losses. The costs, of course, are much higher. The enthusiasm for hydrogen as energy storage is misplaced. Electricity to hydrogen to electricity is maybe 40% efficient. Lithium batteries are 80% - 90% round trip. In any place that needs air conditioning, solar power is very effective. P…

Lithium batteries are not portable, hydrogen can be. With sufficient solar power generation that forty odd percent efficiency would become a non issue.

[deleted]

Re: Building solar farms above the clouds

#10
How are these things supposed to stay aloft? They need to lift:

1) Themselves

2) The solar panels

3) Fuel cells

4) 20km of tether and cable

The idea seems really neat, but I'm an engineer and I want to see the math.

Edit: And how about that tether? What's the wind load going to be like? How is it moored? What is it made of?

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