Energy transfer in solar panels

AI Thread Summary
Compound A, with a higher albedo and lower emissivity, is suggested to be more effective at transferring energy to water behind solar panels despite Compound B reaching a higher temperature and emitting more energy at thermal equilibrium. While B absorbs more energy and emits 960W compared to A's 920W, the discussion emphasizes the role of albedo in energy absorption and transfer efficiency. The lower reflectivity of A allows it to absorb more sunlight, which may enhance its overall energy transfer capability to the water. The conversation highlights the complexity of energy transfer dynamics, suggesting that factors beyond simple emissivity and temperature must be considered. Ultimately, the effectiveness of energy transfer in solar panels involves a balance of albedo, emissivity, and thermal dynamics.
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Compound A has an albedo value (visible spectrum) of 0.08, and an emissivity (infrared) of 0.08.
Compound B has an albedo value of 0.04 and an emissivity of 0.88, in the same spectrums.

We need to explain why A is more effective at transferring energy to the water flowing behind it, when used as a coating on a solar panel.

So far, I've determined that (imagining the incident sunlight is, say, 1000W)...

- B reaches a higher temperature when at thermal equilibirum
- B reflects 40W, absorbs 960W, and thus emits 960W at thermal equilibirum
- A reflects 80W, absorbs 920W, and thus emits 920W at thermal equilbirum

So B is both at a higher temp (and thus has a higher transfer of energy by Newton's law of cooling) and it's also emitting 960W, as opposed to 920W for A.
So everything seems to be pointing to B as a more effective energy transferrer.
Where am I going wrong?

Thanks :)
 
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This is falling quickly off the front page so I'm going to be petulent and bump it.
Didn't post any formulas because alfredo/reflectivity and emissivity are pretty much just ratios.
 
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