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More of it is reflect back into space from many natural surfaces than from solar panels. Not scientific but look how black this solar farm appears compared to t

More of it is reflect back into space from many natural surfaces than from solar panels. Not scientific but look how black this solar farm appears compared to the surrounding land https://eoimages.gsfc.nasa.gov/images/imagerecords/85000/85403/topaz_oli_2015002_lrg.jpg https://eoimages.gsfc.nasa.gov/images/imagerecords/85000/854...

XorNot 4y ago
Right and so to follow this logic through, how do you think we get energy out of fossil fuels? Or nuclear reactors? Or a hypothetical fusion power plant?
- sacrosancty 4y ago
  Steam turbines? What are you trying to say?
  - XorNot 4y ago
    > they are designed to turn the only external source of energy our planet receives (sun light) into heat and other forms of energy that will eventually become heat How does a steam turbine work? By heat: we burn things to get heat, and use steam to turn it into work which..turns it into heat. Your own statement is arguing against using energy in the first place, yet trying to frame it as a "renewable energy" problem as though the 60% of energy in gasoline isn't being thrown off into the environment, and 30-50% of energy in coal isn't the same, or as if literally every last bit of that - all of it because of the laws of thermodynamics - isn't eventually turned into heat. Total estimate energy consumption per year [1] is about 14420 TWh as of 2021. The total solar energy we would've received in that same year [2] is 1,515,480,000 TWh. Or 0.00095%. The amount of thermal emission from human activity on Earth is negligible. The idea that the amount of solar panels to power human civilization would have any non-local effect on the temperature of the planet is absurd. [1] https://en.wikipedia.org/wiki/World_energy_supply_and_consumption/energy/global-energy-consumption https://en.wikipedia.org/wiki/World_energy_supply_and_consum... [2] https://news.mit.edu/2011/energy-scale-part3-1026 https://news.mit.edu/2011/energy-scale-part3-1026
    - sacrosancty 4y ago
      I wasn't arguing against the use of solar panels, just pointing out that they don't reflect light as much as the natural environment that would have been in their place. This whole discussion is purely academic because the proportion of earth covered by solar panels is negligible.
coryrc 4y ago
I doubt that picture is recording most of the wavelengths of light responsible for getting heat back into space.
- sacrosancty 4y ago
  It's mainly the visible wavelengths that can get through the atmosphere. You should see the absorption spectrum for water, it's remarkably transparent in the visible! That's how the greenhouse effect works - longer wavelength thermal radiation is blocked by greenhouse gasses.
  - coryrc 4y ago
    Visible light is also the ones turned into electricity, so it would make sense for panels to not be highly reflective at them.
    - sacrosancty 4y ago
      Yes, that's why they're dark! But it doesn't change the fact that they're dark.
    - petre 4y ago
      It also heats up dark surfaces. One way to remove that heat would be to have some kind of combined PV + solar thermal panel. The other lower tech option is to cover your roof with soil and plants, which release the heat back during the night. Vegetation is esentially a heat buffer.

XorNot 4y ago

Right and so to follow this logic through, how do you think we get energy out of fossil fuels? Or nuclear reactors? Or a hypothetical fusion power plant?

sacrosancty 4y ago
Steam turbines? What are you trying to say?
- XorNot 4y ago
  > they are designed to turn the only external source of energy our planet receives (sun light) into heat and other forms of energy that will eventually become heat How does a steam turbine work? By heat: we burn things to get heat, and use steam to turn it into work which..turns it into heat. Your own statement is arguing against using energy in the first place, yet trying to frame it as a "renewable energy" problem as though the 60% of energy in gasoline isn't being thrown off into the environment, and 30-50% of energy in coal isn't the same, or as if literally every last bit of that - all of it because of the laws of thermodynamics - isn't eventually turned into heat. Total estimate energy consumption per year [1] is about 14420 TWh as of 2021. The total solar energy we would've received in that same year [2] is 1,515,480,000 TWh. Or 0.00095%. The amount of thermal emission from human activity on Earth is negligible. The idea that the amount of solar panels to power human civilization would have any non-local effect on the temperature of the planet is absurd. [1] https://en.wikipedia.org/wiki/World_energy_supply_and_consumption/energy/global-energy-consumption https://en.wikipedia.org/wiki/World_energy_supply_and_consum... [2] https://news.mit.edu/2011/energy-scale-part3-1026 https://news.mit.edu/2011/energy-scale-part3-1026
  - sacrosancty 4y ago
    I wasn't arguing against the use of solar panels, just pointing out that they don't reflect light as much as the natural environment that would have been in their place. This whole discussion is purely academic because the proportion of earth covered by solar panels is negligible.

coryrc 4y ago

I doubt that picture is recording most of the wavelengths of light responsible for getting heat back into space.

sacrosancty 4y ago
It's mainly the visible wavelengths that can get through the atmosphere. You should see the absorption spectrum for water, it's remarkably transparent in the visible! That's how the greenhouse effect works - longer wavelength thermal radiation is blocked by greenhouse gasses.
- coryrc 4y ago
  Visible light is also the ones turned into electricity, so it would make sense for panels to not be highly reflective at them.
  - sacrosancty 4y ago
    Yes, that's why they're dark! But it doesn't change the fact that they're dark.
  - petre 4y ago
    It also heats up dark surfaces. One way to remove that heat would be to have some kind of combined PV + solar thermal panel. The other lower tech option is to cover your roof with soil and plants, which release the heat back during the night. Vegetation is esentially a heat buffer.