If all of mankind’s energy was supplied through solar panels would the effect be big enough to decrease the temperature (since light is converted in part to electricity)?
If all of mankind’s energy was supplied through solar panels would the effect be big enough to decrease the temperature (since light is converted in part to electricity)?
No. If a watt worth of sunlight hits the earth, it’s transformed into a watt of heat. If it hits a solar panel, it’s transformed into some heat and some electricity, which is then used to power something that then transformed it into heat. The only solar energy that doesn’t heat up the planet is the one that is reflected back into space, which, however, isn’t much for solar panels.
However, if you use a watt of sunlight to power your phone instead of a watt of energy you got from burning coal, this watt of energy instead stays below earth and therefore doesn’t heat up the planet. It also doesn’t release co2, which would otherwise reduce the atmosphere’s reflectivity, trapping even more sun heat on the planet.
So solar panels don’t reduce the temperature by not allowing sunlight to heat up the planet, they decrease the temperature by replacing other stuff that would otherwise heat up the planet.
Solar panels aren’t 100% efficient though, so isn’t a bunch of it is reflected back in to space?
Isnt the energy also stored in batteries until ready to be used?
Yeah, so what? Eventually, it’ll be heat.
Just to be pedantic CO2 absorbs bands in the infrared and reemits it, energy that otherwise could be lost to space. This is part of the reason you can’t do infrared telescopes from earth.
https://news.climate.columbia.edu/2021/02/25/carbon-dioxide-cause-global-warming/
Water is an even more powerful greenhouse gas but fortunately the earth is cool enough for it to condense back out of the atmosphere. If temps got high enough that more evaporated than condensed then you’d get a runaway greenhouse effect and we’d be truly fucked.
Your comment in pictures:
Just note that the released energy of burning fossils (or nuclear) is orders of magnitude below what the sun does. It really is only the CO2 from coal (or CO2 and CH4 from natural gas, …) that does the heating, since it acts like insulation.
Yeah, that explanation sounded off to me. CO2 and other greenhouse gases are the issue, not heat directly released from combustion. The sun is doing the overwhelming majority of heating. Carbon staying underground matters far more than watts staying underground.
Plants fixing carbon also converts energy to a form that isn’t heat, so I think we should count that along with reflection as a way that solar energy doesn’t become terrestrial heat.
Correct, but not only is it extremely little, this stored energy is also quickly released again after the organism dies.
Quick in geologic time. But this is what fossil fuels are, so it’s an order of magnitude or two different than the time in which generated electricity will be used.
And you’re right, it’s very small. Everything we know is pretty small, even combined. The amount of energy the sun imparts to the Earth every day equals what humanity would use over about 12 years at current levels.
No, quickly as in years. There is no more coal or oil formed today, there are now organisms that can digest every part of organic stuff. There were none back then for example for lignin from wood, which is where we got coal from.
What?
Fossil fuels are carbon.
That carbon was sequestered from the atmosphere millions of years ago.
Burning fossil fuels releases that carbon into the atmosphere, which then makes the earth hotter
Think of oil as dead dinosaurs and coal as dead trees, that’s basically what it is.
All that stuff was taken out of circulation over an insanely long timeline, and now on a very short timeline we’re digging it up and putting it back into circulation. So fast that species can’t adapt to the change and die out before they can evolve.
My highlights had nothing to do with fossil fuels.
This?
The “watt of energy” is a watt from the coal… And they’re saying to leave the coal buried and sequestered.
I assumed that was understood, so I explained how burning coal heats up the planet…
You may have not realized what you highlighted had to do with fossil fuels, but that’s just because you didn’t understand.
Which is fine, you did the right thing and asked questions.
Burning coal doesn’t significantly heat the planet directly. The CO2 released by this causes solar heating to be more effective by trapping the escaping infrared radiation. It’s the greenhouse gases that are the issue, not the energy released by combustion. “Watts staying underground” is a poor explanation. Burning coal makes watts from the sun more effective at heating the earth.
Participate pollution melts glaciers which increases the temperature long after it fucks shit up by trapping heat in the atmosphere and blocking photosynthesis.
Just saying “watts staying underground” is a poor explanation. That’s an insignificant amount of energy compared to what the sun is delivering and what’s being trapped by CO2. “Carbon staying underground” is much more the priority.
Which is why I clarified for someone what someone else likely meant…
I’m not sure what you’re doing here, do you want me to go complain to the person who first used that phrasing on your behalf?
That’s not really relevant. Fine particulate emissions from coal power plants, which are already mostly gone in the US but are still used around the world, don’t travel a really long distance.
No, they do.
Precipitate pollution from coal use in India and China is making it to the northern glaciars.
It doesn’t need to be a lot, a small speck on a glacier can “snowball” into a substantial melt because black soot gets hotter than white snow.
https://www.nbcnews.com/sciencemain/coal-soot-darkened-melted-glaciers-during-industrial-revolution-8C11069699
It’s not like the soot has to blanket it, especially when they’re already melting.
Grammatically, coal was not the subject of that sentence. But that’s fine, I see what OP was going for.
Weird choice to downvote the person who helped you understand, but you do you I guess.
It’s definitely convinced me not to spend anytime helping you in the future though. So maybe don’t be like this to the next person, Lemmy is small and there’s only so many people to help you, eventually you’ll run out.
I downvote those who downvote me. No worries, I didn’t really need your “help”.