Do solar cells lower ambient temperature b/c they are absorbing light rays or raise it b/c of the reaction?
Question:
Answer:
It depends on what the solar cells are replacing.
Let's say the original surface was a pool of water or a mirrored surface, which reflected all the light back into space. Now a big solar cell, even though it converts most of its energy into electricity, is still a very dark object, and will absorb some of the light as heat and reradiate it out that way.
If however, the surface was black tar, asphalt, or very dark roofing tile, then the solar cell would be converting more of the light energy into electricity than just turning it into heat.
This will also depend on the quality of the solar cell you're using, since commercial grades can range from 40%-90% conversion efficiency.
But either way, it isn't that big of a difference.
as solar cells convert thermal energy into electrical energy .ENERGY IS NEITHER CREATED NOR DESTROYED UNLESS IT IS TRANSFORMED FROM ONE FORM TO OTHER. the ambient temperature remains more or less same
It depends on what you mean by "ambient".
Solar cells absorb solar radiation (energy) that might otherwise have been reflected back to space. That extra energy goes into heating the cell itself until its outgoing radiation plus its electrical energy output equals the incoming radiation.
Locally, the ambient temperature depends on the efficiency of the solar cells. A very efficient cell stays cooler than a less efficient one because more incident energy is converted to electricity.
Ultimately, though, the electricity is used somewhere and there the "ambient" environment is warmed.
On a global scale- the more solar cells are deployed, the more the planetary albedo is decreased. To the extent there is a net decrease in albedo, the planet HAS to warm to stay in radiation equilibrium.
I guess the totally "green" solution is to install reflective panels along with your solar panels such that the net planetary albedo is unchanged.
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