Solar Lab Post

For this eco-friendly author, one technology that has always seemed feasible for greater use has been that of solar powered devices. But when the actual practicality of the technology is examined, does reality meet my expectations? This is the question that initially piqued my curiosity when it was announced that the latest in class experiment would involve solar cells. The scope of the investigation may have been downgraded a bit from that which was conjured up by my illustrious imagination, but the information collected would serve to increase my knowledge about the feasibility of solar technology nonetheless.
Kept within the confines of our “laboratory”/classroom, my partner and I were given the task of determining if the color of light had any discernable impact upon its absorption a solar cell; in other words, as all colors are a result of variance in light wavelengths, how does a solar cell respond to the differing wavelengths. Aiding our inquisition were several tools: a small flashlight, a small solar cell, the chassis-computer of the robots from previous experiments, translucent colored tiles of various hues, and a piece of scientific software called Labview.
The experiment itself was conducted in several stages, in order to provide the greatest possible wealth of data. As a control, our first trial was run with the cell left undisturbed, absorbing only as much light as would be provided by the fluorescent bulbs lining the ceiling. Subsequent tests of the solar cell without a tile were run by holding the flashlight to it at the increasing distances of 5 cm, 15 cm, 22.5 cm and 30 cm. We also ran a test of the cell covered by our hands, to see how it operated in pitch black conditions. Below is a graph of our results from this no-filter experiment; please note how the amount of light absorbed forms an inverse relationship with the distance at which the flashlight was held (the amount of light absorbed was recorded in the number of volts produced by the cell:

However, this hardly satiated our curiosity. Quickly after seeing these results, my partner and I began investigating how the colored tiles affected the voltage-production of the solar cell. With a flashlight held at the fixed distance of 15 cm, we sought to see the differences in light absorption as the color of the tile used alternated. As the following bar graph indicates, while discrepancies did arise in our findings, none were especially significant. Preforming best (defined here as generating the greatest voltage) was the orange filter at 0.389 watts; the ignominy of least voltage generation belonged to was the blue filter at 0.309 watts, though it should be noted that the red filter was not at all far behind at .315 watts.

Bearing in mind these many results, several conclusions may be drawn about solar cell technology. Primarily, our experiment with unfiltered distance proves that proximity to the light source is a critical component in the generation of electricity. The data also points to the necessity of utilizing unfiltered sunlight, as the electrical output of our tests run at 30 cm without a filter surpassed those conducted at 15 cm with any color filter. In sum, the stronger the light to strike the panel, the more electricity that shall be generated.