(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

how many photons does the sun generate to knock one electron across the bandgap in a PV panel? I am doing a college level night school course on Photovoltaics and I have to do a short presentation on photons and how they produce useable energy. I thought it would be interesting to work out this question. Assume a panel is %15 efficient and %40 of the photons are blocked by the atmosphere.

2. Relevant equations

3. The attempt at a solution

I assume it takes one photon to knock one electron across the bandgap. So working backwards, the panel is %15 efficient so 1/.15=6.66. Next, we lost %40 to the atmosphere so 6.66/.4=16.66 so 16.66 photons would have to strike the atmosphere to knock one electron across the bandgap. I am stumped by the next step but I know it will be a huge number. Lets assume no photons are lost in the trip from the sun. Does this even make sense?

Thanks

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# Homework Help: How many photons does the sun generate to

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