why don't solar panels contribute to global warming?
I've been wondering this for a while but I have not yet encountered an explanation.
This is from my understanding of physics, which is by no means expert, so sorry for my crude explanation:
Energy within earth can be considered a closed system; it transforms but cannot be created or destroyed -- and from what I understand, heat seems to be its most natural form, so it will always end up like that in some way.
Two things affect the total sum of energy on earth: radiation into space will drain energy (and is limited because of the presence of atmosphere). Radiation from the sun adds energy to the system.
Basically the sun is our only real source of energy (and we can consider it limitless, since when the sun is exhausted, we're over anyway).
The way I understand it, solar panels increase the efficiency of how we 'harvest' this solar energy, reflecting less of it back into space, and turning more of it into en energy (in this case, electrical). So we take more energy from the sun by putting solar panels in place. But the amount of energy that is removed from the system stays the same.
Hence the total sum of energy on earth increases (more) when we use solar panels. 912
So how come we consider them to be a way to counter global warming, instead of a contributing factor?
edit: since all answers are about comparing solar cells to fossil fuels, let me clarify a bit more.
I understand that fossil fuels will contribute more to climate change than solar cells -- but I just wanted to clarify that is seems to me that both are a net negative (not if you replace one by the other). In other words, that the idea that solar cells are 100% clean (apart from production cost), is not really true, then. Wind of hydro however, would be, since they use energy that is already present in the earth system. (and of course what we really need to do is require less energy) 591