Comment by kryogen1c
3 days ago
I have always had this concern about wind and solar. Removing energy from one part of the earth always sounded very haphazard and untestable.
It's very unclear to me that removing heat from the ground, reducing wind speed/pressure, and lowering tidal forces is guaranteed to never have catastrophic impact.
Do you have this same concern about literally every structure man has ever constructed?
They do the same exact thing in terms of 'slowing wind down' and 'preventing the sun's energy from reaching the ground'.
This idea is understandable, but it falls apart for the same reason the wind turbine bird death concern does (the number of birds that have died due to humans liking windows is 1,000,000x the number that have died in turbines).
> Do you have this same concern about literally every structure man has ever constructed?
To a lesser extent, yes. However, power generating facilities are different in that they are intended to remove as much energy as possible, whereas sky scrapers etc are not.
This is exactly why science education is so important.
But if it makes you feel better, all man made structures combined cover a small fraction of the earths surface people tend to be in areas with other people and thus it looks like we’re doing more than we are. NYC for example has 291x the average population density of the rest of the US and that’s including over a square mile devoted to Central Park.
Agriculture has a bigger impact because it cover so much land, but that’s offset by it being relatively close to nature.
Cities probably have a significantly larger effect on the way that energy flows around the earth than renewable power generation does. It's relatively easy to change how much a very large amount of heat moves in comparison to how easy it is to harness energy into usable work. (See also why the greenhouse effect from CO2 emissions is such a big deal in comparison to basically any other thing that humans have done, as far as the energy balance of the earth is concerned. CO2 is responsible for about 20 times more energy being absorbed by the earth than humanity uses in total, from any source)
Sure, but again, wind turbines are on the scale of millions whereas there are tens of billions of structures swaying in the breeze.
I get your point, but a 1,000x+ difference in quantity cannot be ignored.
Wind turbines can have local effects, meaning less wind in areas behind the turbines, which can mean smog stays longer in a city.
But like the other comment said, with solar you are not taking anything.
But solar panels do heat up the air around them more than vegetation would do.
They do. But they also keep that heat from reaching the ground, which is a good thing for many agricultural applications.
See also, "Agrivoltaics."
With solar humanity's total power consumption is just a fraction of a percent of the Sun's luminance. With wind in some areas you get towards a larger percentage. But either one pales in comparison to the impact of hydropower which has dammed some of the largest rivers and waterfalls in the world to offer only a small fraction of our existing electricity supply.
Its all a question of scale. All these systems can afford some extra energy loss just like the planet could cope with a certain amount of CO2 production because the plants and oceans would grab it and store it. Once we exceed those (currently unknown) limits however it can become a problem and the biggest solar farms are impacting the area around them as they change that energy balance.
At this point i think removing any heat from ground is a net win.
Solar is just transforming light into electricity, i don’t think it’s removing any heat from the system unfortunately, unlike radiative cooling paint.
Now that we should be painting any tropical building we can with.
I would expect large solar farms increase heat, as the panels are dark and absorb a lot of energy (by design). Normal groundcover is not so dark and reflects a higher percentage of sunlight.
Considering how little of the landmass needs to be covered, any effects are absolutely trivial compared to CO2 gains.
>removing heat from the ground
You're not removing anything, you're just transforming kinetic energy into electrical energy. Energy transforms, everything transforms on earth, as per the laws of physics. When you die, your body doesn't get "removed", it gets transformed into worm food. It's the cycle of matter and energy. "Yeah science Mr. White!"
I doubt human devices that capture wind and water wave energy are enough to negatively impact the climate in a meaningful way, considering how powerful nature is.
"In a closed system entropy always goes up
That's the second law, now you know what's up
You can't win, you can't break even, you can't leave the game
Cause entropy will take it all 'though it seems a shame"
-MC Hawking
> I doubt human devices that capture wind and water wave energy are enough to negatively impact the climate in a meaningful way
Exactly what we used to say about industrial gas emissions.
And to take this to its ultimate conclusion, that electrical energy eventually gets turned back into heat one way or another.
If you drive an Nvidia 5090 and an Intel i9-14900KS then yes, it gets converted back to heat but that can also be reused like in some dorm rooms in Finland that are heated by the waste heat of the Nokia networking equipment.
During transfer, the source experiences removal.
Covering the ground in non transparent panels removes heat from the ground.
Yes.
The side effects of solar panels is indeed a cooler ground underneath. Plants have difficulty growing in the shade.
Panels have a darker shade than most ground they are covering, so they might actually absorb more heat than the typical ground they are covering. They are distorting the local albedo.
I think for geocooling by solar panels shade, the effect is completely local and only surface deep. After all stone/ground is an insulator, and geothermal energy is considered renewable.
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It prevents some heat from reaching the ground there (solar panels are ~20% efficient: most of the energy still reaches the ground). The energy (energy + heat is generally more than would normally be absorbed by heat in the ground) gets used and then turns into... heat. Which either makes it into the air or the ground, which is where it was going to wind up anyway.
That's why you install solar panels where covering the ground has little to no impact, like on top of urban buildings or deserts where nothing lives or grows.
Strictly speaking nothing, including posting HN comments, is guaranteed to never have catastrophic impact.
We all need to live with some calculated risks.
> Removing energy from one part of the earth always sounded very haphazard and untestable.
.. compared to taking energy and carbon from the ground, and changing the atmospheric composition enough to significantly change the temperature? Because that's the alternative to not-renewables.
Yeah everything has an effect. I have been quietly strangling infants in their cots to prevent CO2 increase from their breathing resulting in runaway climate change. We need to take action and stop disrupting a system in homeostasis. We need to go back to the era of 10,000 humans and I volunteer everyone else to sacrifice themselves for my future.