Climate Change / Global Warming Discussion

[JRP3]

More unexpected consequences of climate change:

Mustard Supply Sees Shortages Due to Climate Crisis

Your favorite punchy yellow burger condiment could be in short supply this summer.

www.yahoo.com

 

[mspohr]

There’s a simple way to unite everyone behind climate justice – and it’s within our power | George Monbiot

Developed by campaigners in some of the world’s most exploited countries, it’s a brilliant idea: simple but systemic. Rich nations owe a massive climate debt to poorer nations: for the devastating impacts of the fossil fuels we have burned. Yet they have no intention of paying for the loss and damage they have caused. Poor countries are deemed to owe massive financial debts to the rich nations, yet they cannot pay them without destroying their economies and their ecosystems. The proposal is simultaneously to cancel both the climate and the financial debts, liberating the money poorer nations need to take climate action. Debt for Climate, mobilising labour, social and climate movements in 28 countries, will be launched by campaigners during the G7 summit in Germany, which starts on Sunday.

Campaigners often talk of “odious debts”, which means loans agreed by dictatorships, that provide no benefit to the nation. But all the debts deemed to be owed by poor nations to the rich world and its corporations could be seen this way. The idea that the global south, looted and enslaved for centuries, should owe money to its exploiters is grotesque.

An analysis in the journal Global Environmental Change suggests that $10tn of value is extracted from poorer countries by richer ones every year, in the form of raw materials, energy, land and labour. That’s 70 times as much money as would be needed to end extreme poverty worldwide. This extraction provides rich nations with a quarter of their GDP: much of our apparent wealth depends on exploitation.

 

[DrGriz]

There’s a simple way to unite everyone behind climate justice – and it’s within our power | George Monbiot

Developed by campaigners in some of the world’s most exploited countries, it’s a brilliant idea: simple but systemic. Rich nations owe a massive climate debt to poorer nations: for the devastating impacts of the fossil fuels we have burned. Yet they have no intention of paying for the loss and damage they have caused. Poor countries are deemed to owe massive financial debts to the rich nations, yet they cannot pay them without destroying their economies and their ecosystems. The proposal is simultaneously to cancel both the climate and the financial debts, liberating the money poorer nations need to take climate action. Debt for Climate, mobilising labour, social and climate movements in 28 countries, will be launched by campaigners during the G7 summit in Germany, which starts on Sunday.

Campaigners often talk of “odious debts”, which means loans agreed by dictatorships, that provide no benefit to the nation. But all the debts deemed to be owed by poor nations to the rich world and its corporations could be seen this way. The idea that the global south, looted and enslaved for centuries, should owe money to its exploiters is grotesque.

An analysis in the journal Global Environmental Change suggests that $10tn of value is extracted from poorer countries by richer ones every year, in the form of raw materials, energy, land and labour. That’s 70 times as much money as would be needed to end extreme poverty worldwide. This extraction provides rich nations with a quarter of their GDP: much of our apparent wealth depends on exploitation.

A lot of truth in there. Unfortunately, corporations have more rights than people.

 

[Norbert]

I don't understand why federal support for solar (both rooftop and farms, both implementation of current technology and innovation/research) isn't simply increased by a substantial factor, separately from any other complicating measures, as solar itself is very popular in the US.

To me that seems a simple individual step to take.

 

[eevee-fan]

Another step toward being able to live underground!

Interesting Engineering: A new breakthrough in biology allows scientists to grow food without sunlight.

https://interestingengineering.com/breakthrough-in-biology-grow-food-without-sunlight

 

[Norbert]

That’s a good point. Without doing a thermal analysis I’m not sure how it all balances out.

Perhaps there would be a tiny effect if solar panels reflect light within the visible spectrum back all the way into space. However I don't think that solar panels do that. Even if they did, the area of the planet covered by panels will always remain a tiny percentage. And the argument was that there is a portion converted into electricity instead of heat. Now that simply means that it will do something first, before that electricty will also become heat when it is used. Before that becomes some kind of myth.

 

[Norbert]

Most Americans support expanding solar and wind energy, but Republican support has dropped

Among Republicans, support for increasing reliance on solar power is down from 84% last year to 73% today.

www.pewresearch.org

Support for more solar farms (as of June 2021)

Democrats: 93%
Republicans: 73%

So maybe a first step for substanial increase of renewables could focus on solar specifically, and avoid getting hung up on other issues.

 

[eevee-fan]

Perhaps there would be a tiny effect if solar panels reflect light within the visible spectrum back all the way into space. However I don't think that solar panels do that. Even if they did, the area of the planet covered by panels will always remain a tiny percentage. And the argument was that there is a portion converted into electricity instead of heat. Now that simply means that it will do something first, before that electricty will also become heat when it is used. Before that becomes some kind of myth.

Right, so no difference between a 30% efficient fossil fuel plant generating new heat vs solar panel that converts solar to electricity then releases heat?!?

I am talking about stored heat from the sun beating down on a surface that later gets released at night. It's called the heat island effect of cities, read about it.

 

[Norbert]

Right, so no difference between a 30% efficient fossil fuel plant generating new heat vs solar panel that converts solar to electricity then releases heat?!?

Of course that is a difference, but not what the original post (or even yours) was talking about. The original post was about that solar panels convert photons into electricity instead of heat, to some degree, and therefore these photons produce less heat than otherwise. Which is true but yet has no effect for the reasons mentioned.

I am talking about stored heat from the sun beating down on a surface that later gets released at night. It's called the heat island effect of cities, read about it.

So if I understand your point correctly, that mean less heat at night and more heat during the day, so the weather report would show even higher temps?

The heat island effect refers to 2 things as far as I understand: cities reflecting less light than greenery/landscape, and moisture vaporizing having a cooling effect. The first I did mention above, and the second surely doesn't apply to solar panels.

 

[ZsoZso]

Now that simply means that it will do something first, before that electricty will also become heat when it is used. Before that becomes some kind of myth.

Not all use of electricity turns into heat. What about the 90+% efficient electric motors in EVs ? They turn most of the electricity into motion of the car instead of heat. What about LED lights used in more and more for lights in homes that are also highly efficient so very little of the energy is wasted as heat ? Or vacuum cleaners and various household appliances (washing machine etc). Each turns some portion of the energy into heat as waste product but not the majority. There are also industrial processes that use electricity other than heat generation, e.g. Aluminum production.

 

[Norbert]

Not all use of electricity turns into heat. What about the 90+% efficient electric motors in EVs ? They turn most of the electricity into motion of the car instead of heat. What about LED lights used in more and more for lights in homes that are also highly efficient so very little of the energy is wasted as heat ? Or vacuum cleaners and various household appliances (washing machine etc). Each turns some portion of the energy into heat as waste product but not the majority. There are also industrial processes that use electricity other than heat generation, e.g. Aluminum production.

Those are all important benefits, but not in regard to heat except for the better efficiency of EVs and LEDs. The motion of an EV also results in heat (by friction), and indoors LED lights do heat the wall the light falls on. There is nowhere else for the energy to go.

The only question is if the solar panel reflects more non-infrared light upwards than the surface that the sunlight would fall on if the soar panel wasn't there. That's theoretically possible, I don't know, but I wouldn't expect it since on photos, solar panels seem to be darker than the other surfaces.

The real benefit of solar panels is that over their lifetime their construction produces less greenshouse gases than the fossil fuel that would be burned otherwise, and the energy and resources needed to provide that fuel. These greenhouse gases reflect the (infrared) heat back to the surface, so it gets trapped on the planet.

 

[eevee-fan]

So if I understand your point correctly, that mean less heat at night and more heat during the day, so the weather report would show even higher temps?

The heat island effect refers to 2 things as far as I understand: cities reflecting less light than greenery/landscape, and moisture vaporizing having a cooling effect. The first I did mention above, and the second surely doesn't apply to solar panels.

Looks like you need to review the definition:

And how does having a fossil fuel plant generate electricity and dump 70% of the energy as heat (vs solar which is neutral) into the environment help with temperatures?

 

[Norbert]

Looks like you need to review the definition:

Unless I'm missing something, 3 categories are mentioned in the video:

Heat from absorbing sunlight (and storing the resulting heat) as opposed to reflecting the light:
I have talked about that already, there is a possible difference, but I would expect solar panels to absorb more sunlight since they appear darker. (However I don't have numbers ready for that either.)

Cooling from water evaporation:
Solar panels wouldn't increase water evaporation in the usual situations.

Heat from energy consumption (traffic, air conditioning):
That is independent of solar panels, and also it is usually considered a secondary component, AFAIK.

And how does having a fossil fuel plant generate electricity and dump 70% of the energy as heat (vs solar which is neutral) into the environment help with temperatures?

Obviously it doesn't, but nobody was talking about a fossil fuel plant. You buy a solar panel because you want to use the electricity for something useful, not because the electricity it produces would reduce the heat.

If you want to look at the heat of the whole system, including power plant (be it fossil fuel or wind energy or a solar farm), then you have to compare the heat produced by the power plant to the heat produced by the sunlight absorbtion of the solar panel, which depends on how much visible or invisible light it reflects (or how 'dark' it is).

 

[Norbert]

...or to put it like this: if you quickly install a solar panel to run your washing machine during the day, as opposed to running it at night, that will not have a cooling effect within your house during the day.

 

[eevee-fan]

Unless I'm missing something, 3 categories are mentioned in the video:

Heat from absorbing sunlight (and storing the resulting heat) as opposed to reflecting the light:
I have talked about that already, there is a possible difference, but I would expect solar panels to absorb more sunlight since they appear darker. (However I don't have numbers ready for that either.)

Cooling from water evaporation:
Solar panels wouldn't increase water evaporation in the usual situations.

Heat from energy consumption (traffic, air conditioning):
That is independent of solar panels, and also it is usually considered a secondary component, AFAIK.

Obviously it doesn't, but nobody was talking about a fossil fuel plant. You buy a solar panel because you want to use the electricity for something useful, not because the electricity it produces would reduce the heat.

If you want to look at the heat of the whole system, including power plant (be it fossil fuel or wind energy or a solar farm), then you have to compare the heat produced by the power plant to the heat produced by the sunlight absorbtion of the solar panel, which depends on how much visible or invisible light it reflects (or how 'dark' it is).

Yes, you are missing the heat retention effect of concrete and rocks compared to the same area shaded by solar panels. Big difference. Plus, solar panels shed heat into the night sky at night, helping to cool the surrounding area.

I'm pretty sure everyone is talking about a fossil fuel plant. From what advanced tech does energy magically appear from a fossil fuel plant without waste heat? That's like saying solar powered EV and gas cars emit the same amount of heat, an obvious falsity.

You might want to be posting your disinformation on the Climate Change Denialism thread. LOL

 

[Norbert]

Yes, you are missing the heat retention effect of concrete and rocks compared to the same area shaded by solar panels. Big difference. Plus, solar panels shed heat into the night sky at night, helping to cool the surrounding area.

Well, I was asking about that when I wrote:
"So if I understand your point correctly, that mean less heat at night and more heat during the day, so the weather report would show even higher temps?"

And I would ask the same question again:
If the area shaded by solar panels would store/retain heat otherwise, then doesn't that mean that now, with solar panels, there is less heat stored and therefore more heat during the day?

Or are you saying the solar panels store more heat than the shaded area would? I would doubt that solar panels store a lot of heat, although certainly more than zero.

I'm pretty sure everyone is talking about a fossil fuel plant. From what advanced tech does energy magically appear from a fossil fuel plant without waste heat? That's like saying solar powered EV and gas cars emit the same amount of heat, an obvious falsity.

You might want to be posting your disinformation on the Climate Change Denialism thread. LOL

That's misplaced sarcasm. Of course that is a more important fact, but not what the original post was about, which said explicitely:
..."so in a way photovoltaic solar panels help in more than one way (not just replacing energy generated by fossil fuel burning)".

That is what this was about: an effect *aside* from "replacing energy generated by fossil fuel burning". And it even ackowledged that it was an effect that is "probably negligible". So that is just what we were saying: It is *really* negligible, if not zero.

So probably zero, without denying anything. At which point I'll end this discuussion, unless you have a surprising answer to the question above.

 

[mspohr]

And I would ask the same question again:
If the area shaded by solar panels would store/retain heat otherwise, then doesn't that mean that now, with solar panels, there is less heat stored and therefore more heat during the day?

Or are you saying the solar panels store more heat than the shaded area would? I would doubt that solar panels store a lot of heat, although certainly more than zero.

I have seen numerous studies which show that solar panels reduce water evaporation from underlying land and generally improve growing conditions for crops.
This seems to be because of shading, absorption of photons to generate electricity and radiation of excess heat back to the sky.

Agrivoltaics: Solar and Agriculture Co-Location

Agrivoltaics, or the practice of solar agriculture co-location, is defined as agricultural production underneath or adjacent to solar panels, such as crops, livestock, and pollinators.

www.energy.gov

Introduction to Solar PV on Farms under the SMART Program

The Massachusetts Department of Energy Resources’ (MA DOER) Solar Massachusetts Renewable Target (SMART) program serves as a successor to the state’s Solar Renewable Energy Credit (SREC II) program. SMART regulations took effect on November 26, 2018 and were updated via an Emergency Regulation...

ag.umass.edu

The Benefits of Implementing Solar PV Systems in the Agricultural Industry | Capital Solar Group

capitalsolargroup.com

 

[Norbert]

Adding to the previous post regarding heat retention, I think I can already explain more, preempting your answer:

Heat storage/retention goes together with absorbtion of sunlight. Absorbtion (the absence of reflecting the light) is the part that creates the heat, on the surface.

The storage/rentention just means that this heat is partially released at night instead of immediately during the day.

So the amount of absorbtion determines the amount of heat, and the amount of storage/retention just determines when this heat effect is seen, what percentage of it will become effective at night instead of during the day.

It means that the effect of absorbtion will increase temperatures both during the day and at night.

But the primary factor is still the absorbtion, as opposed to reflection, of sunlight.

Which is just a clarification of the physics. And, of course, yes you are right, fossil fuel power plants create much more heat. Just not what this was about.

 

[Norbert]

I have seen numerous studies which show that solar panels reduce water evaporation from underlying land and generally improve growing conditions for crops.
This seems to be because of shading, absorption of photons to generate electricity and radiation of excess heat back to the sky.

Good point and much more important than the discussion we were having about heat. This applies to solar panels that are not on rooftops. I also think that this can be a real benefit.

Regarding heat, however, reducing water evaporation means less cooling and therefore more heat to a certain degree. But the CO2 of fossil fuel has a *much* larger effect on heat, and again I also see less water evaporation as a good thing, and more important than that bit of heat.

EDIT:
Regarding the physics, I would think that this is because sunlight absorbtion on the surface concentrates heat on the surface where it causes water evaporation. Since solar panels don't have water, placing a solar panel above the ground will not cause water evaporation on the surface anymore. The reduced water evaporation will cause an increase of heat, but this is around the solar panel, in the air, and that will cause less evporation since it is not concentrated on the surface anymore. Just my guess how this works.

 

[eevee-fan]

Good point and much more important than the discussion we were having about heat. This applies to solar panels that are not on rooftops. I also think that this can be a real benefit.

Regarding heat, however, reducing water evaporation means less cooling and therefore more heat to a certain degree. But the CO2 of fossil fuel has a *much* larger effect on heat, and again I also see less water evaporation as a good thing, and more important than that bit of heat.

EDIT:
Regarding the physics, I would think that this is because sunlight absorbtion on the surface concentrates heat on the surface where it causes water evaporation. Since solar panels don't have water, placing a solar panel above the ground will not cause water evaporation on the surface anymore. The reduced water evaporation will cause an increase of heat, but this is around the solar panel, in the air, and that will cause less evporation since it is not concentrated on the surface anymore. Just my guess how this works.

If you want an understandable demonstration in your garage this winter.

Experiment 1:
Put a radiative heater facing down.
Turn on heater on high for 6 hours.
Turn off heater.
Place a thermometer on the garage floor and measure the temp.

Experiment 2:
Put a radiative heater facing down.
Put a folding table between the heater and the floor (so it absorbs and radiates heat while shielding the floor from heating, just like a solar panel).
Turn on heater on high for 6 hours.
Turn off heater.
Place a thermometer on the garage floor and measure the temp.