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Maybe this is a stupid question but I wonder if there are any ecological concerns about redirecting terawatts of power from the photons hitting Earth into elect

Maybe this is a stupid question but I wonder if there are any ecological concerns about redirecting terawatts of power from the photons hitting Earth into electricity. Of course, it's bound to be a big net win over burning hydrocarbons. But is there any drawback?

skybrian 4y ago
Yes, whatever is under the solar panels gets less sunlight. There are even some companies starting to lay solar panels directly on the ground, which means it gets none at all. I don't think it's all that hard to take that into account, though; it's a land use concern. What was the land being used for before? Also, the terawatts of power generated will get converted to heat in developed areas where it's used, but that's true of any electricity use.
- ScottBurson 4y ago
  But if the sunlight that produced that power had hit something else instead, it also would have been turned into heat. There's no net heating of the planet from solar power. (Of course, the distribution of heating can change.)
  - dhc02 4y ago
    Yes, and when electricity is used to do work, the vast, overwhelming majority of the energy used is turned into heat. So solar panels are moving heat, not sending it into a black hole somewhere.
    - ScottBurson 4y ago
      That was my point.
  - rootusrootus 4y ago
    Recall that PV panels are black. They get quite hot, almost certainly hotter than plain dirt would if uncovered. Plenty hot enough that you can't touch them for more than a moment.
    - 8note 4y ago
      For reference, that's somewhere just above 50°C
  - 41b696ef1113 4y ago
    I am not sure that is correct. It is possible that solar panels absorb more total energy and keep it locally than would otherwise be reflected back into space via radiative cooling.
    - thereisnospork 4y ago
      Possibly, although it would behoove solar panels to have a high albedo along the non-electrically producing wavelengths. Lower panel temperatures mean higher efficiency, but the effort might not be worth the marginal improvement.
magnio 4y ago
At 100TW, solar power would use a whooping 0.06% of total solar radiation the Earth receives. The Sun is truly immense. The biggest environmental concern is the disposing of the batteries when they die, and that should seen solutions soon as solar gets more and more popular.
- a_wild_dandan 4y ago
  The overwhelming majority of solar energy storage will likely be in batteries with little need for disposal: giant spinning flywheels, pumping water up high, storing energy in millions of smart thermostat homes by overheating/cooling them during peak hours to reduce demand at other hours, etc.
  - WalterBright 4y ago
    Finally, I see mention of the HVAC "battery" idea I've been flogging for years. Progress! I hope this progresses to using the pile-of-rocks "battery" to store heat/cold in cheap hours and draw on it in expensive hours.
    - beefield 4y ago
      You might be interested to read about a seasonal thermal storage project in Vojens, Denmark: https://deepresource.wordpress.com/2020/12/16/district-heating-with-seasonal-storage-in-vojens-denmark/ https://deepresource.wordpress.com/2020/12/16/district-heati...
      - WalterBright 4y ago
        Looks like the Danes are very smart!
    - wumpus 4y ago
      It was popular in the 1950s. Deployed near where you live, even.
      - 4y ago
jacobparker 4y ago
Consider that 40% of American corn crop (created, as you say, by redirecting the suns energy) is turned into Ethanol, to be burned for energy. Solar panels are "roughly 200 times more energy per acre than corn" according to https://pv-magazine-usa.com/2022/03/10/solarfood-in-ethanol-fields-could-fully-power-the-united-states/ https://pv-magazine-usa.com/2022/03/10/solarfood-in-ethanol-... There are ecological concerns but the alternatives have them too.
8note 4y ago
There's an albedo change where previously the light would have reflected back out. The melting ice is likely a bigger change, considering some of the solar is going on dark rooftops that already bake in the sun

skybrian 4y ago

Yes, whatever is under the solar panels gets less sunlight. There are even some companies starting to lay solar panels directly on the ground, which means it gets none at all. I don't think it's all that hard to take that into account, though; it's a land use concern. What was the land being used for before? Also, the terawatts of power generated will get converted to heat in developed areas where it's used, but that's true of any electricity use.

ScottBurson 4y ago
But if the sunlight that produced that power had hit something else instead, it also would have been turned into heat. There's no net heating of the planet from solar power. (Of course, the distribution of heating can change.)
- dhc02 4y ago
  Yes, and when electricity is used to do work, the vast, overwhelming majority of the energy used is turned into heat. So solar panels are moving heat, not sending it into a black hole somewhere.
  - ScottBurson 4y ago
    That was my point.
- rootusrootus 4y ago
  Recall that PV panels are black. They get quite hot, almost certainly hotter than plain dirt would if uncovered. Plenty hot enough that you can't touch them for more than a moment.
  - 8note 4y ago
    For reference, that's somewhere just above 50°C
- 41b696ef1113 4y ago
  I am not sure that is correct. It is possible that solar panels absorb more total energy and keep it locally than would otherwise be reflected back into space via radiative cooling.
  - thereisnospork 4y ago
    Possibly, although it would behoove solar panels to have a high albedo along the non-electrically producing wavelengths. Lower panel temperatures mean higher efficiency, but the effort might not be worth the marginal improvement.

magnio 4y ago

At 100TW, solar power would use a whooping 0.06% of total solar radiation the Earth receives. The Sun is truly immense. The biggest environmental concern is the disposing of the batteries when they die, and that should seen solutions soon as solar gets more and more popular.

a_wild_dandan 4y ago
The overwhelming majority of solar energy storage will likely be in batteries with little need for disposal: giant spinning flywheels, pumping water up high, storing energy in millions of smart thermostat homes by overheating/cooling them during peak hours to reduce demand at other hours, etc.
- WalterBright 4y ago
  Finally, I see mention of the HVAC "battery" idea I've been flogging for years. Progress! I hope this progresses to using the pile-of-rocks "battery" to store heat/cold in cheap hours and draw on it in expensive hours.
  - beefield 4y ago
    You might be interested to read about a seasonal thermal storage project in Vojens, Denmark: https://deepresource.wordpress.com/2020/12/16/district-heating-with-seasonal-storage-in-vojens-denmark/ https://deepresource.wordpress.com/2020/12/16/district-heati...
    - WalterBright 4y ago
      Looks like the Danes are very smart!
  - wumpus 4y ago
    It was popular in the 1950s. Deployed near where you live, even.
    - 4y ago

jacobparker 4y ago

Consider that 40% of American corn crop (created, as you say, by redirecting the suns energy) is turned into Ethanol, to be burned for energy. Solar panels are "roughly 200 times more energy per acre than corn" according to https://pv-magazine-usa.com/2022/03/10/solarfood-in-ethanol-fields-could-fully-power-the-united-states/ https://pv-magazine-usa.com/2022/03/10/solarfood-in-ethanol-... There are ecological concerns but the alternatives have them too.

8note 4y ago

There's an albedo change where previously the light would have reflected back out. The melting ice is likely a bigger change, considering some of the solar is going on dark rooftops that already bake in the sun