Quote:
Originally Posted by Christ
Question about PV cells... can a PV be made that any light will actually get through?
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No.
Sorry.
PV works. . .because the photons that make up light "happen" to strike the electrons in the waifer as they pass through. The semi-conductor has an electron sharing quality that allows them to be popped out of orbit easily enough that a passing photon that happens to occupy the same space at the same time can bounce them out of orbit. The photon then passes the rest of teh way through the first membrane and strike the second and is absorbed as heat, or in the case it did not strike an electron in layer 1 it may still have enough energy to pop an electron loose in layer 2. PV is difficult because you are relying on the probability that a photon will strike an electron.
Of course we can improve our odds(originally PV produced far less like only 1% of the time did a photon bounce an electron out of orbit opposed to the 20% we see now) by using things that are better semi-conductors and allow for a more. . .evenly(?) distributed electron field to improve our chances of a collision. Thats what the big race in PV is. Find a semi-conductor compound that distributes electrons in a fashion that they are out there and get a "hit" 50% of the time. . .or actually just 25% of the time per layer for a total of 50%. . .different materials for different wavelengths of light otherwise it just sails right past.(Blue and Green are the most common forms of light in our solar system thats why they are blue and green(also why plants are green)).