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Question:

Why are solar panels only 0% efficient?

The average solar panel produces 0% of the energy that is put into it. What is happening to the other 90%? Is it being reflected or is it being obsorbed by materials that are not a part of the solar cell? Is it possible to one day have near 00% efficient solar cell technology?

Answer:

Mainly due to reflection (micro-structuring of the surface helps here), incorrect wavelength of the light (the panel is only sensitive to a certain wavelength range) and heating of the panel (due to the incident light/thermal radiation). The remainder is either reflected or absorbed by the cell and re-emitted as heat. Absorption by e.g. the glass panel is slight (a few %), as is absorption/reflection by the necessary surface contacts (again, a few %). Higher efficiency is possible, but brings its own drawbacks (like higher cost). You could now go into two directions: - high efficiency cells/panels with (likely) higher cost and complexity for mounting (like lens or mirror based systems, aka concentrator systems, that increase the light level on the cells in order to increase efficiency) - low cost systems (cheap as dirt) that will allow you to cover every surface of a building, efficiency is less important if you can compensate by a much larger covered area As to the efficiency limit: there is a theoretical limit (from thermodynamics - don't ask me how or why) in the range of 30...40%, depending on which publication you want to believe in.
Sunlight comes in many frequencies, that's why it's white. Solar Photovoltaics require a photon to displace an electron from a semiconductor and that only happens at one frequency depending on what the semiconductor material is, therefore only one exact frequency gets turned into power. They are working on using organic dyes or quantum dots to absorb the energy in different frequencies and re-emit the energy in the desired frequency. They also are working on using multiple semiconductor materials to try and capture more frequencies. The rest of the energy becomes heat which also reduces the efficiency of the solar cells. The lab record for solar photovoltaics is 42.8% efficiency and quantum dots promises to be 65% to 75% efficient. Keep in mind that fossil fuels are based on energy collected by photosynthesis over millions of years. The efficiency of photosynthesis with modern plants is about 0.5% and the theoretical maximum efficiency of photosynthesis is 6.6%. All of our current energy use is based upon a small fraction of 0.5% efficiency over millions of years.
intense frequency waves alongside with x-ray or UV are additionally particularly intense lively while in comparison with the soak up-ale wavelength (which i think is many times infra-pink). so if we are able to make panels that soak up those wavelength rather of the warmth of infra-pink waves, we'd in all danger be getting a lots larger performance than 0%. desire it helped
Unlikely that we gan get to near 00% efficiency, although there is room for improvement. In the meantime, don't pooh-pooh 0% efficiency. That's about the rate of energy transfer up a food pyramid, perhaps a little less at the solar to plant level. As this manages to provide the basis for most of life on earth, it's nothing to sneeze at. As far as the other 90% goes, I would guess that much of it is reflected.

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