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Has anyone ever considered the effects of wind and solar power on the climate? If wind drives turbines, the energy is not available anymore to circulate air in

by tcmb 5y ago

Has anyone ever considered the effects of wind and solar power on the climate? If wind drives turbines, the energy is not available anymore to circulate air in the atmosphere. And if solar energy is absorbed to a high degree by solar panels, it won't heat up the earth as it used to do before. So, it seems like a fallacy to think that increasing wind and solar power will have not influence the climate. Is this line of thinking present in the current discussion, or is it not valid?

detritus 5y ago
Given that both of these situations draw energy from the atmosphere, they should be complementary to the goals of climate change mitigation. I suppose 'covering the Sahara in solar panels' might need a little thought in regards to how it affects weather patterns across North Africa and Europe, but we're a wee way off from there yet.
- tcmb 5y ago
  Agreed for solar, but I don't see how a reduction of wind energy would contribute to the goal of keeping the temperature increase below a certain level. Kinetic energy is not driving temperature increase, is it?
  - detritus 5y ago
    I suppose not, but reducing wind energy at near sea level would reduce the energy of weather systems, including hurricanes, that whilst products of climate change are the pointy ends of the stick that cause irritation and woe in humans and other creatures. Again, probably not much, mind!
  - PaulDavisThe1st 5y ago
    Other way around. Temperature increase drives kinetic energy in the atmosphere.
mepiethree 5y ago
The total amount of wind and solar in the world is several orders of magnitude higher than the amount that we would harness so this isn’t really a relevant consideration. It’s like asking if a piece of dust on an Olympic sprinter would slow them down due to air resistance.
- tcmb 5y ago
  I hope you're right. Is this true also if we were to replace all current nuclear and fossil energy? There is also the effect (the name of which I currently can't remember) that consumption increases when people think it does no harm. Like when LED lights were introduced, energy usage allegedly actually increased. Because people were using LED lights for all kinds of things that were NOT using incandescent lights before, as the energy used was thought to be negligible.
  - dahart 5y ago
    > Like when LED lights were introduced, energy usage allegedly actually increased. This is not true. More lights might be on, but the total energy usage for lights is currently falling with increased LED production. You can find lots of stated fears and speculation on the internet that it could happen - FUD - but not evidence. There is some indirect evidence not specific to LEDs that people sometimes do use more energy when the cost goes down. But LEDs are an order of magnitude more efficient than incandescents, and there has been no such 10x increase in lighting use. Per-capita electricity use in the US is currently falling slowly.
  - mepiethree 5y ago
    The effect is called Jevons Paradox. That is not a relevant consideration in this particular case, but it is a major concern for things like air conditioning efficiency. https://en.m.wikipedia.org/wiki/Jevons_paradox https://en.m.wikipedia.org/wiki/Jevons_paradox
- detritus 5y ago
  Laterally, the amount of CO2 my existence releases each year is of absolutely no consequence to the global environment. The amount of CO2 that 1Bn others like me - or 8.5Bn if overall living standards increase, however?
vhgyu75e6u 5y ago
I think I lost a neuron reading your comment. You think that the state of New York lost all its wind when they built all the skyscrapers in a comparable small portion of the state?
- detritus 5y ago
  On a very local scale, the creation of all those skyscrapers has a significant effect on wind speeds at street level. As for the energy required to make the concrete, steel and glass that made those same buildings, that has increased the amount of wind that New York has to deal with so indirectly - 'yes', in answer to your question. I think OP means more 'at the hugely massive scale we appear to need' which I don't think is as neuron-murdering a thought experiment as you so unkindly suggest.
gilbetron 5y ago
In spite of the harsh response of some people to your question, it is a perfectly valid question that has some studies addressing it: https://news.harvard.edu/gazette/story/2018/10/large-scale-wind-power-has-its-down-side/ https://news.harvard.edu/gazette/story/2018/10/large-scale-w... Basically, yes, wind power can have effects on the climate, and we should be aware of them and use them to weigh tradeoffs with other power generation options. This is a reasonable question to ask!
- dahart 5y ago
  That article is a pretty misleading summary of the situation, IMO. Keith’s paper does demonstrate very localized effects that people living near wind farms might care about, but does not show any significant or even measurable global effects, nor does it actually represent serious negative concerns about wind power in general, especially in relation to coal. https://www.sciencemediacentre.org/expert-reaction-to-research-on-climatic-impact-of-wind-power/ https://www.sciencemediacentre.org/expert-reaction-to-resear...
joconde 5y ago
I imagine that the effect is so small that it's negligible. Wouldn't an entire forest block more wind than a field of turbines? And forests aren't known to have that kind of effect. Solar panels are also on a tiny fraction of the Earth's surface, the rest receives and treats radiation the same way as always.
- pfdietz 5y ago
  If the efficiency of the solar module is > the albedo of the ground on which it is mounted, it can actually cause net local cooling. And of course a thermal source like nuclear pumps out 3x as much heat pollution (2x at the plant, 1x at the place the power is used). Direct thermal pollution is still very minor globally, compared to heating from increased greenhouse gases.
snowwrestler 5y ago
It’s valid in that everything has an effect, but it’s not really a concern. One reason is that, as other commenters pointed out, the total volume of wind and solar is currently tiny compared to the energy delivered to the Earth’s surface from the sun. So the size of the effect is not large enough to be noticeable, or probably even measurable. The other reason involves the mechanics of how wind and solar work. Solar (photovoltaic) converts electromagnetic energy that would otherwise heat the atmosphere, directly into electricity. But, it converts probably less energy than you think (solar panels still get hot in the sun, i.e. they still radiate in the infrared). And, once the electricity is used by people to do work, the energy is converted back into atmospheric heat. No heat is lost; energy can’t be destroyed. Wind turbines do absorb energy from the wind, but only from the wind they can reach, which is mostly regional. There is a boundary layer close to the Earth’s surface (below a few thousand feet above mean ground level) where air movement is relatively slow and chaotic. That’s what we experience as “wind” and what wind turbines can reach. But most atmospheric heat transport happens via extremely powerful and persistent air currents higher in the atmosphere. You may have heard of the “jet stream” for example. Wind turbines in high enough concentration could conceivably have a regional effect on wind patterns (just like tall buildings do) but it’s basically adding a small amount of local chaos to a part of the atmosphere that is already small and chaotic, like adding a couple new rocks to the bottom of a river. You might create some new little eddies along the bottom, but you’re not meaningfully affecting the main flow.
dahart 5y ago
People have considered it. There are two reasons that you can summarize this as “it doesn’t matter”: 1- wind and solar (and hydro) are so much better than coal when it comes global warming and other negative environmental impact, the main reason to bring up “concerns” is entrenched economic interests, and not real fears of increased warming. The fact is that renewable sources are net cooling - and not by a little - compared to the warming we’re already causing with coal burning and CO2 emissions. 2- The scale of the earth’s atmosphere and surface area are “very large” compared to our solar and wind farms. So large that it might seem funny at first to think turbines or solar cells would have any effect. One way to think about turbines is that they’re somewhat comparable to trees, and we’ve lost many times more trees in the last 50 years than we’ve added turbines. Another way is to compare the height of a turbine (say, 100 meters) to the height of the wind (maybe 400 km, depending how you measure), so the turbines touch maybe 1/4000 of the vertical air, and across the world cover very little of the total land area, meaning the total volume of air impacted by turbines is ‘tiny’. According to my internet searches just now, the earth’s land surface (1.5e14 m^2) gets, on average, 2.4e16 watts of solar power. [1] The total solar power production today is just less than 800GW, or 8e11 watts. [2] So solar might be capturing one thirty-thousandth of the surface energy, or 0.003%. (And that actually seems surprisingly large to me, it’s possible I’m missing more orders of magnitude somewhere. I don’t think solar farms are covering anywhere near as much as 0.003% of the surface of the earth.) Atmospheric energy is about half of the surface energy, and wind is currently capturing roughly the same as solar [3], so maybe we could estimate it about 0.006% of the wind energy. [1] https://earthobservatory.nasa.gov/features/EnergyBalance https://earthobservatory.nasa.gov/features/EnergyBalance [2] https://iea-pvps.org/snapshot-reports/snapshot-2021/ https://iea-pvps.org/snapshot-reports/snapshot-2021/ [3] https://en.wikipedia.org/wiki/Wind_power_by_country https://en.wikipedia.org/wiki/Wind_power_by_country

by tcmb 5y ago

detritus 5y ago

Given that both of these situations draw energy from the atmosphere, they should be complementary to the goals of climate change mitigation. I suppose 'covering the Sahara in solar panels' might need a little thought in regards to how it affects weather patterns across North Africa and Europe, but we're a wee way off from there yet.

tcmb 5y ago
Agreed for solar, but I don't see how a reduction of wind energy would contribute to the goal of keeping the temperature increase below a certain level. Kinetic energy is not driving temperature increase, is it?
- detritus 5y ago
  I suppose not, but reducing wind energy at near sea level would reduce the energy of weather systems, including hurricanes, that whilst products of climate change are the pointy ends of the stick that cause irritation and woe in humans and other creatures. Again, probably not much, mind!
- PaulDavisThe1st 5y ago
  Other way around. Temperature increase drives kinetic energy in the atmosphere.

mepiethree 5y ago

The total amount of wind and solar in the world is several orders of magnitude higher than the amount that we would harness so this isn’t really a relevant consideration. It’s like asking if a piece of dust on an Olympic sprinter would slow them down due to air resistance.

tcmb 5y ago
I hope you're right. Is this true also if we were to replace all current nuclear and fossil energy? There is also the effect (the name of which I currently can't remember) that consumption increases when people think it does no harm. Like when LED lights were introduced, energy usage allegedly actually increased. Because people were using LED lights for all kinds of things that were NOT using incandescent lights before, as the energy used was thought to be negligible.
- dahart 5y ago
  > Like when LED lights were introduced, energy usage allegedly actually increased. This is not true. More lights might be on, but the total energy usage for lights is currently falling with increased LED production. You can find lots of stated fears and speculation on the internet that it could happen - FUD - but not evidence. There is some indirect evidence not specific to LEDs that people sometimes do use more energy when the cost goes down. But LEDs are an order of magnitude more efficient than incandescents, and there has been no such 10x increase in lighting use. Per-capita electricity use in the US is currently falling slowly.
- mepiethree 5y ago
  The effect is called Jevons Paradox. That is not a relevant consideration in this particular case, but it is a major concern for things like air conditioning efficiency. https://en.m.wikipedia.org/wiki/Jevons_paradox https://en.m.wikipedia.org/wiki/Jevons_paradox
detritus 5y ago
Laterally, the amount of CO2 my existence releases each year is of absolutely no consequence to the global environment. The amount of CO2 that 1Bn others like me - or 8.5Bn if overall living standards increase, however?

vhgyu75e6u 5y ago

I think I lost a neuron reading your comment. You think that the state of New York lost all its wind when they built all the skyscrapers in a comparable small portion of the state?

detritus 5y ago
On a very local scale, the creation of all those skyscrapers has a significant effect on wind speeds at street level. As for the energy required to make the concrete, steel and glass that made those same buildings, that has increased the amount of wind that New York has to deal with so indirectly - 'yes', in answer to your question. I think OP means more 'at the hugely massive scale we appear to need' which I don't think is as neuron-murdering a thought experiment as you so unkindly suggest.

gilbetron 5y ago

In spite of the harsh response of some people to your question, it is a perfectly valid question that has some studies addressing it: https://news.harvard.edu/gazette/story/2018/10/large-scale-wind-power-has-its-down-side/ https://news.harvard.edu/gazette/story/2018/10/large-scale-w... Basically, yes, wind power can have effects on the climate, and we should be aware of them and use them to weigh tradeoffs with other power generation options. This is a reasonable question to ask!

dahart 5y ago
That article is a pretty misleading summary of the situation, IMO. Keith’s paper does demonstrate very localized effects that people living near wind farms might care about, but does not show any significant or even measurable global effects, nor does it actually represent serious negative concerns about wind power in general, especially in relation to coal. https://www.sciencemediacentre.org/expert-reaction-to-research-on-climatic-impact-of-wind-power/ https://www.sciencemediacentre.org/expert-reaction-to-resear...

joconde 5y ago

I imagine that the effect is so small that it's negligible. Wouldn't an entire forest block more wind than a field of turbines? And forests aren't known to have that kind of effect. Solar panels are also on a tiny fraction of the Earth's surface, the rest receives and treats radiation the same way as always.

pfdietz 5y ago
If the efficiency of the solar module is > the albedo of the ground on which it is mounted, it can actually cause net local cooling. And of course a thermal source like nuclear pumps out 3x as much heat pollution (2x at the plant, 1x at the place the power is used). Direct thermal pollution is still very minor globally, compared to heating from increased greenhouse gases.

snowwrestler 5y ago

It’s valid in that everything has an effect, but it’s not really a concern. One reason is that, as other commenters pointed out, the total volume of wind and solar is currently tiny compared to the energy delivered to the Earth’s surface from the sun. So the size of the effect is not large enough to be noticeable, or probably even measurable. The other reason involves the mechanics of how wind and solar work. Solar (photovoltaic) converts electromagnetic energy that would otherwise heat the atmosphere, directly into electricity. But, it converts probably less energy than you think (solar panels still get hot in the sun, i.e. they still radiate in the infrared). And, once the electricity is used by people to do work, the energy is converted back into atmospheric heat. No heat is lost; energy can’t be destroyed. Wind turbines do absorb energy from the wind, but only from the wind they can reach, which is mostly regional. There is a boundary layer close to the Earth’s surface (below a few thousand feet above mean ground level) where air movement is relatively slow and chaotic. That’s what we experience as “wind” and what wind turbines can reach. But most atmospheric heat transport happens via extremely powerful and persistent air currents higher in the atmosphere. You may have heard of the “jet stream” for example. Wind turbines in high enough concentration could conceivably have a regional effect on wind patterns (just like tall buildings do) but it’s basically adding a small amount of local chaos to a part of the atmosphere that is already small and chaotic, like adding a couple new rocks to the bottom of a river. You might create some new little eddies along the bottom, but you’re not meaningfully affecting the main flow.

dahart 5y ago

People have considered it. There are two reasons that you can summarize this as “it doesn’t matter”: 1- wind and solar (and hydro) are so much better than coal when it comes global warming and other negative environmental impact, the main reason to bring up “concerns” is entrenched economic interests, and not real fears of increased warming. The fact is that renewable sources are net cooling - and not by a little - compared to the warming we’re already causing with coal burning and CO2 emissions. 2- The scale of the earth’s atmosphere and surface area are “very large” compared to our solar and wind farms. So large that it might seem funny at first to think turbines or solar cells would have any effect. One way to think about turbines is that they’re somewhat comparable to trees, and we’ve lost many times more trees in the last 50 years than we’ve added turbines. Another way is to compare the height of a turbine (say, 100 meters) to the height of the wind (maybe 400 km, depending how you measure), so the turbines touch maybe 1/4000 of the vertical air, and across the world cover very little of the total land area, meaning the total volume of air impacted by turbines is ‘tiny’. According to my internet searches just now, the earth’s land surface (1.5e14 m^2) gets, on average, 2.4e16 watts of solar power. [1] The total solar power production today is just less than 800GW, or 8e11 watts. [2] So solar might be capturing one thirty-thousandth of the surface energy, or 0.003%. (And that actually seems surprisingly large to me, it’s possible I’m missing more orders of magnitude somewhere. I don’t think solar farms are covering anywhere near as much as 0.003% of the surface of the earth.) Atmospheric energy is about half of the surface energy, and wind is currently capturing roughly the same as solar [3], so maybe we could estimate it about 0.006% of the wind energy. [1] https://earthobservatory.nasa.gov/features/EnergyBalance https://earthobservatory.nasa.gov/features/EnergyBalance [2] https://iea-pvps.org/snapshot-reports/snapshot-2021/ https://iea-pvps.org/snapshot-reports/snapshot-2021/ [3] https://en.wikipedia.org/wiki/Wind_power_by_country https://en.wikipedia.org/wiki/Wind_power_by_country