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Modeled impact of large-scale wind and solar farms in the Sahara

phys.org

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Re: Modeled impact of large-scale wind and solar farms in the Sahara

#11

Post by logfromblammo »

Analemma_ wrote: post #9
wongarsu wrote: post #6

Earlier quoted context omitted.

That seems a bit excessive, considering that the world energy consumption is only about 18 terawatts (and only about 3 terawatts of that are electrical right now).

If countries like China, India, Malaysia, Nigeria etc. start to have per-capita energy use close to that of the United States, global energy consumption could easily double or triple even without any increase in population. I said "if", but I really should say "when", because this is what's expected to happen as these countries modernize and start getting things like air conditioning on the same scale as US household…

Also, if that much excess would otherwise be wasted, we could always use it to smelt aluminum, form it into big tanks, attach standard docking rings, fill them up with water, and launch them into a designated band of refueling orbits. Those would almost certainly be useful later in space technology development.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#12

Post by reaperducer »

wongarsu wrote: post #10

>"The greater nighttime warming takes place because wind turbines can enhance the vertical mixing and bring down warmer air from above," the authors wrote. That's actually a very interesting effect. I guess the votices generated by wind farms quite beneficial in a desert region. It would be interesting to see what effect wind farms have on desertification. Given that two large factors are fertile ground blowing away…

I guess the votices generated by wind farms quite beneficial in a desert region.

Unless you're an ectothermic creature (like a lizard, tortoise, snake, etc...) which relies on the cool of night to hunt food and find water.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#13

Post by spacenick88 »

Analemma_ wrote: post #9
wongarsu wrote: post #6

Earlier quoted context omitted.

That seems a bit excessive, considering that the world energy consumption is only about 18 terawatts (and only about 3 terawatts of that are electrical right now).

If countries like China, India, Malaysia, Nigeria etc. start to have per-capita energy use close to that of the United States, global energy consumption could easily double or triple even without any increase in population. I said "if", but I really should say "when", because this is what's expected to happen as these countries modernize and start getting things like air conditioning on the same scale as US household…

Almost no one in Europe has per-capita energy use anywhere close to the US, so why would China? And I don't think it's just that we have less AC, though that's surely the strongest contributor.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#14

Post by wizardforhire »

logfromblammo wrote: post #11
Analemma_ wrote: post #9

Earlier quoted context omitted.

If countries like China, India, Malaysia, Nigeria etc. start to have per-capita energy use close to that of the United States, global energy consumption could easily double or triple even without any increase in population. I said "if", but I really should say "when", because this is what's expected to happen as these countries modernize and start getting things like air conditioning on the same scale as US household…

Also, if that much excess would otherwise be wasted, we could always use it to smelt aluminum, form it into big tanks, attach standard docking rings, fill them up with water, and launch them into a designated band of refueling orbits. Those would almost certainly be useful later in space technology development.

Or condense air and harvest co2 for sequestering.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#15

Post by sandworm101 »

What they do not model is the local effect of the cities that will need to be built to service all these panels. 9,000,000 square KM is a gigantic area. Millions of people will be needed to maintain these farms. Those people will need to either live locally or be transported regularly. The study should model how the presence of those people in such a relatively underpopulated area will impact local climate.

1 person per km2 = 9million people. But I'd bet you would need a couple dozen people for every km2 of solar farm, and associate infrastructure, meaning perhaps 100 millions people. And then all the people to provide services to those people ... this is like building a few new countries from scratch.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#16

Post by nine_k »

jameskilton wrote: post #3

> The wind and solar farms simulated in the study would cover more than 9 million square kilometers and generate, on average, about 3 terawatts and 79 terawatts of electrical power, respectively. This study is looking at a combined farm size that's almost as large as all the land mass in the US. https://en.wikipedia.org/wiki/List_of_U.S._states_and_territ...

Generating terawatts is not unreasonable. But transportation of it out of North Africa would be almost as big an effort as building the solar farms in question.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#17

Post by e40 »

reaperducer wrote: post #12
wongarsu wrote: post #10

>"The greater nighttime warming takes place because wind turbines can enhance the vertical mixing and bring down warmer air from above," the authors wrote. That's actually a very interesting effect. I guess the votices generated by wind farms quite beneficial in a desert region. It would be interesting to see what effect wind farms have on desertification. Given that two large factors are fertile ground blowing away…

I guess the votices generated by wind farms quite beneficial in a desert region. Unless you're an ectothermic creature (like a lizard, tortoise, snake, etc...) which relies on the cool of night to hunt food and find water.

Yeah, I was thinking that the cool temps at night are necessary for condensation. Without it, the plant and animal life in the region could be devastated.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#18

Post by krupan »

"A new climate-modeling study finds that a massive wind and solar installation in the Sahara Desert and neighboring Sahel would increase local temperature, precipitation and vegetation. Overall, the researchers report, the effects would likely benefit the region."

Beneficial to who or what? Beneficial in what ways?

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#19

Post by ebikelaw »

sandworm101 wrote: post #15

What they do not model is the local effect of the cities that will need to be built to service all these panels. 9,000,000 square KM is a gigantic area. Millions of people will be needed to maintain these farms. Those people will need to either live locally or be transported regularly. The study should model how the presence of those people in such a relatively underpopulated area will impact local climate. 1 person…

Solar utility installations in California that I’m familiar with employ fewer than 1 person per square km.

Re: Modeled impact of large-scale wind and solar farms in the Sahara

#20

Post by abecedarius »

nine_k wrote: post #16
jameskilton wrote: post #3

> The wind and solar farms simulated in the study would cover more than 9 million square kilometers and generate, on average, about 3 terawatts and 79 terawatts of electrical power, respectively. This study is looking at a combined farm size that's almost as large as all the land mass in the US. https://en.wikipedia.org/wiki/List_of_U.S._states_and_territ...

Generating terawatts is not unreasonable. But transportation of it out of North Africa would be almost as big an effort as building the solar farms in question.

How would you go about it? Lots of high-voltage lines, or is there something else that'd make more sense for this unusual setup?
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