How does a solar cell work? Experiment

The experiment this week focused on solar cells. How it works is by generating a voltage on the two wires by shining light onto them. Sunlight hits the material and the lights energy is absorberd by the material. Then the material extracts the electron flow out, creating a voltage. Solar cells are 21% efficient. They are more efficient than a light bulb, but not by much. A light bulb is only 10% efficient. I was very surprised by this. Light bulbs is everyone's main source of light in their homes, I figured there would be a higher efficiency. The point of the experiment was to measure the voltage produced by the light, that would shine on the solar cell. We would study light intensity as well. The higher the energy the higher the voltage. The ultimate goal of the experiment was to look at the amount of voltage that would generate by the provolatic effect in a silicon solar cell. How? By looking at light vs. Distance. The farther away the light will be the lower the intensity. We used a small cell, flashlight, and colored filters. The colors were to block certain wavelengths. So we took the solar cell and first calculated the voltage at 0cm without light; directly against the flashlight. Next it was 0cm with light. Then 4cm, 8cm, 12cm, and 16cm. As predicted, the farther away the flashlight was, the lower the number was. Next was the color filters. We had yellow, blue, green, and red. Blue, green, and red all had a similar number but yellow's was higher. This is because more light was able to get through yellow. Yellow is a close color to what the sun is. Therefore, the amount of light that will get through is greater than other colors. Here are the two graphs created for the experiment: