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

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

#31

Post by mikeyouse »

ebikelaw wrote: post #26
sandworm101 wrote: post #24

Earlier quoted context omitted.

And how do they keep all those panels clean? Who maintains the transformers when they break? Who swaps out the panels as they reach their life expectancy? It isn't just the night watchman, but the entire community of people involved in any large outdoor installation.

Like any utility, you don't need a guy just hanging around waiting for the transformers to explode. You truck him in every 50 years when that actually happens. It's time domain multiplexing, essentially.

The cleaning is largely a solved problem too.. You don't need 50 $10k/year people with squeegees, you just need one person in a $50k truck.

https://www.alibaba.com/product-detail/China-Road-tunnel-wal...

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

#32

Post by xyzzyz »

krupan wrote: post #23
xyzzyz wrote: post #21

Earlier quoted context omitted.

You can continue reading the article to learn the answers, you know.

Sorry, I think the point I was trying to make was, do we really want to transform this unique geography? I live in Utah and if someone came here and said, "you know all this red rock and sand in the south, we could change that into a lush green landscape," there'd be massive opposition to that idea.

Do you think there would a massive opposition if someone came here and offered changing 2% of Utah into lush green landscape? I believe this change would be welcome, as people like some variety. Now, area of Utah is 2% of Sahara's area, so we could literally transform some patch of Sahara of the size of Utah, and still have 98% of it untouched, and get enough electricity to power most of Europe.

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

#33

Post by satya71 »

weberc2 wrote: post #28
xyzzyz wrote: post #22

Earlier quoted context omitted.

We have less AC, but we have more heating, which is more energy intensive than AC.

I’m doubtful about both of these claims (Europe has more heating than the US and that heating is more energy-intensive than AC). The latter seems particularly hard to believe given how efficient heating is compared to A.C.

I don't have the numbers. But intuitively, AC should be less energy as it's energy transfer. Heating is usually directly adding energy to the living environment. You can get heating using heat pumps (some southern US homes have this type) but it doesn't work very well when it's too cold outside. Europe should have more heating than US, with it's more northern location.

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

#34

Post by wongarsu »

spacenick88 wrote: post #13
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…

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.

For reference for anyone curious: the US has a final energy consumption of 6.0kW per capita, the EU average is about 2.9kW. (2009 data)

At that point, China was at 1.3kW/citizen, Africa at half that, India on the level of Africa and the middle East slightly below the EU with 2.3kW.

Wikipedia [2] uses world bank data instead which seems to measure differntly, but the relations are roughtly the same.

1: https://www.eea.europa.eu/data-and-maps/figures/final-energy...

2: https://en.wikipedia.org/wiki/List_of_countries_by_energy_co...

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

#36

Post by TeMPOraL »

satya71 wrote: post #33
weberc2 wrote: post #28

Earlier quoted context omitted.

I’m doubtful about both of these claims (Europe has more heating than the US and that heating is more energy-intensive than AC). The latter seems particularly hard to believe given how efficient heating is compared to A.C.

I don't have the numbers. But intuitively, AC should be less energy as it's energy transfer. Heating is usually directly adding energy to the living environment. You can get heating using heat pumps (some southern US homes have this type) but it doesn't work very well when it's too cold outside. Europe should have more heating than US, with it's more northern location.

Indeed. Heat pumps routinely have efficiencies[0] around 400%-500%, because they're not really "producing cold", they just move energy from one inside to outside (or the other way around).

--

[0] - of course that's a specific meaning of "efficiency"; they're still less than 100% efficient in terms of energy expended on moving other energy around vs. theoretical minimum.

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

#37

Post by TeMPOraL »

nine_k wrote: post #27
abecedarius wrote: post #20

Earlier quoted context omitted.

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?

I suppose that a lot of such transmission lines should be superconductive, if only to help put enough electricity through physically more narrow channels. Even with modern high-temp superconductors, it's a lot of expensive infrastructure, a lot of protective redundancy, and a lot of maintenance.

> Even with modern high-temp superconductors, it's a lot of expensive infrastructure, a lot of protective redundancy, and a lot of maintenance.

Which means lots of local jobs, which may not turn out so bad in the short term.

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

#38

Post by TeMPOraL »

krupan wrote: post #23
xyzzyz wrote: post #21

Earlier quoted context omitted.

You can continue reading the article to learn the answers, you know.

Sorry, I think the point I was trying to make was, do we really want to transform this unique geography? I live in Utah and if someone came here and said, "you know all this red rock and sand in the south, we could change that into a lush green landscape," there'd be massive opposition to that idea.

Question is, what do you care more about - the unique geography, or people living there?

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

#39

Post by xyzzyz »

weberc2 wrote: post #28
xyzzyz wrote: post #22

Earlier quoted context omitted.

We have less AC, but we have more heating, which is more energy intensive than AC.

I’m doubtful about both of these claims (Europe has more heating than the US and that heating is more energy-intensive than AC). The latter seems particularly hard to believe given how efficient heating is compared to A.C.

Sure thing. Heating (space + water) represents nearly 80% of EU household energy use[1], compared to 60% in the US[2]. I have no clue what you mean by "heating is efficient compared to AC". In fact, opposite is true -- unless you use some kind of heat pump, which are very uncommon in Europe, you only get exactly one unit of heating per unit of energy consumed. On the other hand, with AC (which _is_ a heat pump), you get something on the order of 5 units of heat (energy) removed per unit of energy consumed.

[1] - https://ec.europa.eu/eurostat/statistics-explained/index.php... [2] - https://www.eia.gov/energyexplained/index.php?page=us_energy...

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

#40

Post by krupan »

xyzzyz wrote: post #32
krupan wrote: post #23

Earlier quoted context omitted.

Sorry, I think the point I was trying to make was, do we really want to transform this unique geography? I live in Utah and if someone came here and said, "you know all this red rock and sand in the south, we could change that into a lush green landscape," there'd be massive opposition to that idea.

Do you think there would a massive opposition if someone came here and offered changing 2% of Utah into lush green landscape? I believe this change would be welcome, as people like some variety. Now, area of Utah is 2% of Sahara's area, so we could literally transform some patch of Sahara of the size of Utah, and still have 98% of it untouched, and get enough electricity to power most of Europe.

You haven't followed the recent Bears Ears controversy, have you? :-)
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